Small block combo suggestions

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Not sure where the 'has to be closed chamber head' is coming from AJ.....??? Cutting the stock heads about .050-.055" will get them down to around 63 cc's and still leave around .035-.040" open chamber depth.

But following along, rather than the KB232's and mess with the pads (since I doubt he will achieve quench anyway), why not just go to the KB362's? Similar thing without the raised pad, and another 1.4cc's larger compressed volume. With the 362's, you're gonna drop 40 grams of piston/pin weight, and with the 232's, you're adding 86 grams, so it's gonna need a re-balance with any piston change. More $$.....You know how it all goes: "Hmmmm, the bearings look a bit worn.... let's replace them." And on and on.

Just IMHO..... Edlebrock heads on sale from Autozone would be less cost in total $$ and effort than re-vamping the pistons, deck, and bottom end. Some of the $$ for AL heads may come back in resale value.

If 'twer me, I'd be very tempted to just thicken the head gasket with Cometics, and add ARP studs. $300 or so and it's done. (Unless the pushrods are not too short.....dang, it's always sumpthin'! LOL)
 
AJ/FormS said:
Ok, I sharpened my pencil too. Your assembly is nearly n exactly like mine with the exceptiom that my combo runs aluminum heads.
I used the Wallace Calculator.
I used these inputs 4.03bore x 3.58 stroke, with the standard 6.123 rods and an ICA of 59 degrees for the 262 cam. The calculator spits out a Dcr of 8.88 and cylinder pressure of 183psi. To get the 183, I had to input a Scr of 10.7, exactly where mine is currently. To get a 10.7 Scr from the above specs requires a total chamber size of 77.14cc
Still working backwards, this requires some combination of parts and clearances to achieve and is all too easy. Mine was set up with a 4.04 bore, .003 pop up(-.6cc), 5cc eyebrows, 63cc heads and the standard .039 fellPro which I think is 8.9cc.
Doing the math, this totals 76.3cc. My swept is 752.03cc. So (752.03 + 76.3)/76.3 =10.856 Scr.
Now if your overbore is .030, the your swept is 748.3cc
So (748.3+ 77.14)/77.14=10.0700Scr.
And to make the 77.14, with an 8.9 gasket and 5cc eyebrows, requires some combination of head and deck height to total, 77.14-(5+8.9) =63.24. If the KB107s are slightly down say .003, that would be .6cc. so that leaves 62.64cc in your heads.
The point of this exercise is that 182psi is easily possible with the parts that you have and that your Dcr is too high for iron heads and pump gas. I run my combo on 87 and full timing so I know it's not too high for aluminum. There are several guys on here that run quite a bit more Dcr on pumpgas.
But that doesn't help you cuz aluminum heads are not cheap, and for your intended useage really aren't justifiable.
So the way I see it, the money has already been spent on the heads so let's try and keep them. That means you are gonna have to manipulate the Dcr with the other parameters, namely ICA,gasket, and pistons. Since you reall want to keep that little 262, that leaves gasket and pistons. Since the .039 FellPro is a tuff sob and it sets a nice tight squish on closed chamber heads, which yours kindof have to be to be down at around 63cc; That just leaves the pistons.
So your pistons either have to be modified or swapped out.
To mod your pistons will require a reverse D-dome, to maintain the squish. I don't know if the 107s have enough material in the crowns to achieve that, or even if it is permissible to cut them,or if it is cost effective to do that.. But I do know that KB makes pistons with pre-cast cups like that.They are the KB232s with 18cc cups. They also have a nice .050 quench pad that you can use, actually;have to use, to adjust your squish. So lets do the math with those installed; Your heads are around 62.64, the gasket 8.9, no eyebrows , and 18 cc in the cups plus about .64cc in the deck. That totals ; 62.64 + 8.9 +18 + .64 =90.18
And.....(748.3 + 90.18)/90.18 =9.298Scr plugging that into the Wallace calculator gets us a Dcr of 7.75/153psi. That is really good for your intended useage. But, firstly the Q-pad will need to be machined down to fit and if you ever want to upsize the cam, you have no place to go; so this engine is kindof written in stone,that is to say no cam-change allowed. But it will burn 87, and it will be a bit of a tractor as to torque.
Now on the off chance that the pistons were down a little more than "just a little", there is room to pre-plan for a future possible cam-swap. There is some room in the Dcr. So since the pistons are coming out, this would be a good time to maximize the Dcr, by a little decking.The above described combo at a Dcr of 7.75, could be bumped up to 8.00 and still run on pumpgas, probably still on 87. That means by re-decking to make the 8.0, you have room for a larger cam of 1 or maybe 2 sizes.
Keep it mind I made up all the number here for your perusal, the big picture being you are not sunk yet. Get the numbers; head CCs, Deck HT, and we can help you dial it in, and so should your builder be able to.
Now if you wanted to put a different cam in , um...new solution.......lol
But I gotta say a 7.75 Dcr in a 360, in your chassis and for your useage, will not be disappointing.153psi is a pretty decent number.
Click to expand...

Wow. First thank you that took a lot of time I'm sure.
I'm still not sure where I went wrong except for not being there when head work was done. I travel for a living and sometimes I'm gone for a while and that seems to be when things go sideways.
AJ I'm not married to the cam at the time that was one that suited my needs.
I really hate to pull this engine out as we drop them from the bottom and I always find something else to do while everything's apart. And I just don't have the time to do that right now. As I have two planes to finish by spring and an ill 1957 chevy truck that need attention. Wt that said I'm short on time.
A cam swap would be less time consuming and the vacuum is what I need so if that's doable I might entertain that.
Years ago I did a lot of work wt Ultradyne Cams Harold Brookshire but as happens he has past. So I have no one to work wt on a custom grind.

I may just build another short block over the summer but was planning on the next build being a stroker but this car doesn't need that type of engine.

So wt all that said the head change makes the most sense. Unless I can come up wt a cam that might work.
But I tell ya wt this combo right now it's a neck snapper when fuel , temp ,and ignition is working right.
One last thought it doesn't act like a high compression engine It starts easily , doesn't overheat ever , idles great But at 10to 1 It's really not that much
 
jeff1 said:
Wow. First thank you that took a lot of time I'm sure.
I'm still not sure where I went wrong except for not being there when head work was done. I travel for a living and sometimes I'm gone for a while and that seems to be when things go sideways.
AJ I'm not married to the cam at the time that was one that suited my needs.
I really hate to pull this engine out as we drop them from the bottom and I always find something else to do while everything's apart. And I just don't have the time to do that right now. As I have two planes to finish by spring and an ill 1957 chevy truck that need attention. Wt that said I'm short on time.
A cam swap would be less time consuming and the vacuum is what I need so if that's doable I might entertain that.
Years ago I did a lot of work wt Ultradyne Cams Harold Brookshire but as happens he has past. So I have no one to work wt on a custom grind.

I may just build another short block over the summer but was planning on the next build being a stroker but this car doesn't need that type of engine.

So wt all that said the head change makes the most sense. Unless I can come up wt a cam that might work.
But I tell ya wt this combo right now it's a neck snapper when fuel , temp ,and ignition is working right.
One last thought it doesn't act like a high compression engine It starts easily , doesn't overheat ever , idles great But at 10to 1 It's really not that much
Click to expand...


I have posted many times a number of cam grinders who do custom cams. I'll do it one more time to save you looking through a bunch of crap on other threads.

Jim Dowell at Racer Brown
Danny at Cam Motion
Mike at Jones Cams
Bullet has the UD lobes and does custom stuff
Dewayne Porter
Chris Straub
Controlled Induction (I think his name is Rick...I have it written in a notebook)

This is just a few of them. The first three is where I go first to get what I want. All of them can do it. Hope you get what you want. It won't be on the shelf.
 
yellow rose said:
I have posted many times a number of cam grinders who do custom cams. I'll do it one more time to save you looking through a bunch of crap on other threads.

Jim Dowell at Racer Brown
Danny at Cam Motion
Mike at Jones Cams
Bullet has the UD lobes and does custom stuff
Dewayne Porter
Chris Straub
Controlled Induction (I think his name is Rick...I have it written in a notebook)

This is just a few of them. The first three is where I go first to get what I want. All of them can do it. Hope you get what you want. It won't be on the shelf.
Click to expand...
Thank You sir. Now just have to figure out what might work and the trade offs.
 
Ok, Ima gonna rant a bit, and this is not directed specifically at you,Jeff. This is for anybody that may be compromising a combo on a low-vacuum /perceived booster issue.
This is a pet peeve of mine. Low idle vacuum does not mean the brake booster will have issues. It really doesn't affect the booster to any great degree unless either the booster or the check-valve is faulty, or the vacuum is low clear up to the stall-speed.
Sure if your engine idles at sub 10 inches or so, the booster may not come on line the way you might expect, but almost the moment the vacuum goes up, the booster comes on line just like normal. It only needs maybe 12 inches to wake up.With a street type cam this vacuum level is usually achieved long before the stall speed. With an automatic and a TC,any TC,by the time the engine is reved up high enough to move the car, your booster will be all ready to go.The booster should store enough vacuum for a couple of stops at least.
And how often does your automatic car idle down low enough for this to be an issue. The check valve is supposed to lock the vacuum in there. If the booster is working right, once it is evacuated it should hold it's vacuum for a very long time, even if you shut the engine off. When you step on the brake you are actually letting atmospheric air into the booster, and out. Atmospheric air is doing all the work. Atmospheric air is moving into and out of the booster. The little control-valve in there is called an atmospheric valve.
I think there are only two times a low vacuum can be a problem; 1) when you first start it up with a normalized booster,and put it into gear in your garage and the brakes don't hold and you push the nose into the workbench;shame on you for not waiting 5 seconds for the booster to come on line, and 2) while sitting at a redlight with a leaky valve, and the car starts to creep forward. Ok simple solution; turn the idle speed down so it doesn't pull so hard, or put it in neutral.
But say you have a manual tranny. Same as above except rev it up a little before you back out of the garage. That's all there is to it. I've been driving like this for over 15 years. I don't even think about it any more. Look; to back a standard up,you almost always blip the throttle to get a little flywheel inertia going which you then use to get things moving. That lil blip wakes up the booster for me.Then once the car is moving,physics takes over which says a body in motion tends to remain in motion until a new stronger force acts on it.See I did too learn something in hi-school.By the time I am in first gear, again a lil throttle is applied and with that the vacuum rises above the booster threshold and all is good. I have had this same booster on several different combos , up to the 292/508/108 cam,and never have I noticed an issue. In fact, I have this dash-mounted timing control device that lets me crank in up to 7* advance, or dial out 8*, from the driver's seat. When I am moving real slow thru the parking lot, things get a lil jumpy under the hood with the 14* in the dizzy. By cranking the timing back the power pulses weaken and it suddenly gets a lot smoother, 'course the engine loses power, but hey it's a 360, it is fine with just 6* of advance. So with the power loss,the rpm is dropping and so is the vacuum. But you know what? I am riding the brake with one foot and maybe the clutch with the other. And the vacuum is way down deeeeeep in the basement, Yet the brakes are working just fine.
This booster came off a 73Dart 318, or maybe it was a 75, or maybe off the 77 Aspen slanty I striped out. In other words just a regular old A/F body booster.
So, Forget about brake booster issues, on engines with street type cams.
Now as to vacuum operated H-VAC controls I cannot say, except they make vacuum storage balls to help keep your ice cold air blowing to where you pointed it to.lol
Ok, here's the punch-line.
To limit an engines performance,just to ensure the booster is charged up the second you start 'er up, is IMO, um Gee, I can't even think what to compare it too. I tell you what, the go-to cam for a streeter is a 268 cam, pick any cam up to that 268,and the vacuum will be fine once you got the tune in her.Like I said I had no booster issues even with the 292/108/508. That would be an additional 14 degrees of cam, which is about 3 sizes.
Back to you Jeff; pick the cam for your application and operating requirements and don't give the booster any more thought.

To nm9, that was a best guess,based on the other numbers I randomly inserted and because the 232s have a machineable .050 q-pad, I didn't give it any more thought. The machinest can adjust the Q with the more than adequate pad.I estimated the factory heads to be machined down to 63cc, to go along with his statement of the pistons being down in the holes a lil bit. Since we know that they could well be .012 down, or more,I arbitrarily choose .003, which the math then spits out the 63 ish head ccs. Did I not say Pure Speculation?Lemme go check.
Nope I said;
Since the .039 FellPro is a tuff sob and it sets a nice tight squish on closed chamber heads, which yours kindof have to be to be down at around 63cc
And elsewhere;Keep it mind I made up all the number here for your perusal
Click to expand...
 
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You could try the thicker head gaskets to see if that helps and save a couple thousand. It might fix the detonation and might not see any difference on the butt dyno.
 
AJ/FormS said:
Ok, Ima gonna rant a bit, and this is not directed specifically at you,Jeff. This is for anybody that may be compromising a combo on a low-vacuum /perceived booster issue.
This is a pet peeve of mine. Low idle vacuum does not mean the brake booster will have issues. It really doesn't affect the booster to any great degree unless either the booster or the check-valve is faulty, or the vacuum is low clear up to the stall-speed.
Sure if your engine idles at sub 10 inches or so, the booster may not come on line the way you might expect, but almost the moment the vacuum goes up, the booster comes on line just like normal. It only needs maybe 12 inches to wake up.With a street type cam this vacuum level is usually achieved long before the stall speed. With an automatic and a TC,any TC,by the time the engine is reved up high enough to move the car, your booster will be all ready to go.The booster should store enough vacuum for a couple of stops at least.
And how often does your automatic car idle down low enough for this to be an issue. The check valve is supposed to lock the vacuum in there. If the booster is working right, once it is evacuated it should hold it's vacuum for a very long time, even if you shut the engine off. When you step on the brake you are actually letting atmospheric air into the booster, and out. Atmospheric air is doing all the work. Atmospheric air is moving into and out of the booster. The little control-valve in there is called an atmospheric valve.
I think there are only two times a low vacuum can be a problem; 1) when you first start it up with a normalized booster,and put it into gear in your garage and the brakes don't hold and you push the nose into the workbench;shame on you for not waiting 5 seconds for the booster to come on line, and 2) while sitting at a redlight with a leaky valve, and the car starts to creep forward. Ok simple solution; turn the idle speed down so it doesn't pull so hard, or put it in neutral.
But say you have a manual tranny. Same as above except rev it up a little before you back out of the garage. That's all there is to it. I've been driving like this for over 15 years. I don't even think about it any more. Look; to back a standard up,you almost always blip the throttle to get a little flywheel inertia going which you then use to get things moving. That lil blip wakes up the booster for me.Then once the car is moving,physics takes over which says a body in motion tends to remain in motion until a new stronger force acts on it.See I did too learn something in hi-school.By the time I am in first gear, again a lil throttle is applied and with that the vacuum rises above the booster threshold and all is good. I have had this same booster on several different combos , up to the 292/508/108 cam,and never have I noticed an issue. In fact, I have this dash-mounted timing control device that lets me crank in up to 7* advance, or dial out 8*, from the driver's seat. When I am moving real slow thru the parking lot, things get a lil jumpy under the hood with the 14* in the dizzy. By cranking the timing back the power pulses weaken and it suddenly gets a lot smoother, 'course the engine loses power, but hey it's a 360, it is fine with just 6* of advance. So with the power loss,the rpm is dropping and so is the vacuum. But you know what? I am riding the brake with one foot and maybe the clutch with the other. And the vacuum is way down deeeeeep in the basement, Yet the brakes are working just fine.
This booster came off a 73Dart 318, or maybe it was a 75, or maybe off the 77 Aspen slanty I striped out. In other words just a regular old A/F body booster.
So, Forget about brake booster issues, on engines with street type cams.
Now as to vacuum operated H-VAC controls I cannot say, except they make vacuum storage balls to help keep your ice cold air blowing to where you pointed it to.lol
Ok, here's the punch-line.
To limit an engines performance,just to ensure the booster is charged up the second you start 'er up, is IMO, um Gee, I can't even think what to compare it too. I tell you what, the go-to cam for a streeter is a 268 cam, pick any cam up to that 268,and the vacuum will be fine once you got the tune in her.Like I said I had no booster issues even with the 292/108/508. That would be an additional 14 degrees of cam, which is about 3 sizes.
Back to you Jeff; pick the cam for your application and operating requirements and don't give the booster any more thought.

To nm9, that was a best guess,based on the other numbers I randomly inserted and because the 232s have a machineable .050 q-pad, I didn't give it any more thought. The machinest can adjust the Q with the more than adequate pad.I estimated the factory heads to be machined down to 63cc, to go along with his statement of the pistons being down in the holes a lil bit. Since we know that they could well be .012 down, or more,I arbitrarily choose .003, which thye spit out the 63 ish head ccs. Did I not say Pure Speculation?Lemme go check.
Click to expand...


Nice rant AJ.

I would say the other option is the option I use. It keeps me from making a cam choice just based on not driving into my house.

That is, I convert my junk **** over to manual brakes. I have done it, at a minimum, 20 times and every single time the car stopped better. With less effort. I even do it when the engine vacuum is over 14 inches. They just stop better when done correctly. And there is more room to work on them.

Learned this in 1980 from a shop teacher who should have been more than a shop teacher.


Then again, how hard is it to stop a 14.5XX car?
 
I'm against adding gasket for two reasons;1) you lose the tight squish,which by itself helps to reduce or eliminate detonation, you kindof want to keep that. and 2) if you don't bury the pistons with the loss of tight Q, then you may in fact introduce a new source of detonation. The tight Q needs to be in a certain range, and with a lack of it the clearance space needs to be much larger.
EDIT; LeloDart says I screwed up, and he's right.It appears the above is messed up.And he's also right that a fat gasket might save the combo.

A fat-boy gasket is an option for this combo, for a couple of reasons;
#1) nm9 thinks the clearance space is around .035 to .040 on the theoretical 62.xx heads. Adding the .039 gasket, and pistons being down a little say .003, we are now up to say .077.... This would be ok to stay out of detonation due to a too-small clearance space. but now if you add another .038 say, to get the total chamber volume up to what we need, then I suppose that would work too.The total chamber size currently, is theoretically, 77.14cc. Remember this was a fall-out number based on the Wallace calculator results using 182 psi cylinder pressure. To get out of detonation we need around 90cc total chamber volume. So here we go;
90 -(62.xxhead + .6deck + 5eyebrows) = a little under 22cc in the gasket. That's a pretty fat gasket, at around .077 inch.
#2)Now here is the second reason ; These fat-boy gaskets will boot the heads back up to near the stock location, making port matching and intake fitting a bunch easier. So with the .077 gasket and the.035 to .040 head clearance space, we have around .115 total piston to head clearance. And the total chamber volume of around 90cc,brings the Scr down to 9.3, and with the 59*ICA, the Dcr comes in at a nice fuel-friendly 7.75Dcr, and 153psi cylinder pressure. Bottom line is the gasket could be a lil thinner. It will burn 87 no problem with full timing.It will be a lil harder on fuel than the combo with 232 pistons, and it won't be quite as snappy down low, but some like it mellow, like that.
How am I doing?
I like the kb232 solution better cuz it maintains a nice tightQ. The tight Q promotes turbulence, and fuel mixing. This can allow a leaner jet to make the same AFR, and so the fuel useage may be reduced in steady state cruising. It may also allow a lil higher detonation free cylinder pressure. And of course you can't beat the sound coming out the tailpipes.No silly, it's not the tightQ sound, it's the Hi-Compression sound.And you gotta love the little tornados that follow you everywhere your turn-downs go!lol
 
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The manual-brake thing is always an option. For some, not me.I too like my power brakes, especially now as I'm getting older.And softer....
YR, that's twice you've been nice to me.
If you were my wife, I'd be forced to ask you what you want? And I just know she wouldn't be saying what I want to hear. So I'm glad you're not my wife, and I'm glad I don't have to ask,lol........
 
OOps I screwed up, I mixed up my combos; LELO;you are right.
The current combo may have as much or more as .080 squish clearance back there, as stated in post #58.

No the loss of tight Q statement would apply to the previous combo with the KB232s, I screwed up, Lemme go see if i I can edit the junk out and save any kind of dignity.

post 58 edited.Is that any better?
 
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Lelo Dart said:
I thought he had X heads with open chambers and flat top pistons. I don't know how he has any squish.
Click to expand...


I have open chamber heads and squish. It's easy really. And my crevice volume is bitchin'.

Just giving you the day of AJ. Tomorrow is a new day!
 
AJ/FormS said:
Ok, Ima gonna rant a bit, and this is not directed specifically at you,Jeff. This is for anybody that may be compromising a combo on a low-vacuum /perceived booster issue.
This is a pet peeve of mine. Low idle vacuum does not mean the brake booster will have issues. It really doesn't affect the booster to any great degree unless either the booster or the check-valve is faulty, or the vacuum is low clear up to the stall-speed.
Sure if your engine idles at sub 10 inches or so, the booster may not come on line the way you might expect, but almost the moment the vacuum goes up, the booster comes on line just like normal. It only needs maybe 12 inches to wake up.With a street type cam this vacuum level is usually achieved long before the stall speed. With an automatic and a TC,any TC,by the time the engine is reved up high enough to move the car, your booster will be all ready to go.The booster should store enough vacuum for a couple of stops at least.
And how often does your automatic car idle down low enough for this to be an issue. The check valve is supposed to lock the vacuum in there. If the booster is working right, once it is evacuated it should hold it's vacuum for a very long time, even if you shut the engine off. When you step on the brake you are actually letting atmospheric air into the booster, and out. Atmospheric air is doing all the work. Atmospheric air is moving into and out of the booster. The little control-valve in there is called an atmospheric valve.
I think there are only two times a low vacuum can be a problem; 1) when you first start it up with a normalized booster,and put it into gear in your garage and the brakes don't hold and you push the nose into the workbench;shame on you for not waiting 5 seconds for the booster to come on line, and 2) while sitting at a redlight with a leaky valve, and the car starts to creep forward. Ok simple solution; turn the idle speed down so it doesn't pull so hard, or put it in neutral.
But say you have a manual tranny. Same as above except rev it up a little before you back out of the garage. That's all there is to it. I've been driving like this for over 15 years. I don't even think about it any more. Look; to back a standard up,you almost always blip the throttle to get a little flywheel inertia going which you then use to get things moving. That lil blip wakes up the booster for me.Then once the car is moving,physics takes over which says a body in motion tends to remain in motion until a new stronger force acts on it.See I did too learn something in hi-school.By the time I am in first gear, again a lil throttle is applied and with that the vacuum rises above the booster threshold and all is good. I have had this same booster on several different combos , up to the 292/508/108 cam,and never have I noticed an issue. In fact, I have this dash-mounted timing control device that lets me crank in up to 7* advance, or dial out 8*, from the driver's seat. When I am moving real slow thru the parking lot, things get a lil jumpy under the hood with the 14* in the dizzy. By cranking the timing back the power pulses weaken and it suddenly gets a lot smoother, 'course the engine loses power, but hey it's a 360, it is fine with just 6* of advance. So with the power loss,the rpm is dropping and so is the vacuum. But you know what? I am riding the brake with one foot and maybe the clutch with the other. And the vacuum is way down deeeeeep in the basement, Yet the brakes are working just fine.
This booster came off a 73Dart 318, or maybe it was a 75, or maybe off the 77 Aspen slanty I striped out. In other words just a regular old A/F body booster.
So, Forget about brake booster issues, on engines with street type cams.
Now as to vacuum operated H-VAC controls I cannot say, except they make vacuum storage balls to help keep your ice cold air blowing to where you pointed it to.lol
Ok, here's the punch-line.
To limit an engines performance,just to ensure the booster is charged up the second you start 'er up, is IMO, um Gee, I can't even think what to compare it too. I tell you what, the go-to cam for a streeter is a 268 cam, pick any cam up to that 268,and the vacuum will be fine once you got the tune in her.Like I said I had no booster issues even with the 292/108/508. That would be an additional 14 degrees of cam, which is about 3 sizes.
Back to you Jeff; pick the cam for your application and operating requirements and don't give the booster any more thought.

To nm9, that was a best guess,based on the other numbers I randomly inserted and because the 232s have a machineable .050 q-pad, I didn't give it any more thought. The machinest can adjust the Q with the more than adequate pad.I estimated the factory heads to be machined down to 63cc, to go along with his statement of the pistons being down in the holes a lil bit. Since we know that they could well be .012 down, or more,I arbitrarily choose .003, which the math then spits out the 63 ish head ccs. Did I not say Pure Speculation?Lemme go check.
Nope I said;
Click to expand...

AJ I agree wt your brake booster dessertation but I think you may have been misled thinking that was the only area of my concern. My car gets driven by wives ,girlfriends, and non automotive educated individuals. It gets driven in parades , cruises and confined areas.
The vacuum helps in these particular instances
It allows a good clean idle , comfortable brakes to the uneducated, and not having to explain that the engine isn't going to stall out.
So yes low vacuum can work but in some applications it's not the best choice. Much like a5500 stall converter, a 671 blower ,or slicks. on the street it's doable but not fun.
I most definitely appreciate your help I have learned a few things so please keep the info coming. That's one of the biggest reasons I choose to participate in certain forums because you can have open discussions and be exposed to many many different ideas on solving a problem.
 
YR's idea of calling a cam grinder may be a good thing to do. I am not sure I mentioned it in this thread, but Crane had a series of cams in the 70's call HE cams (hydraulic efficiency). These were designed and sold after the 1st Arab oil embargo, so guys with hotter engines could tame it down for better fuel mileage. They had veeery slow ramps between .005" (advertised) and .050"; there was more than 60* difference between advertised and .050" durations, whereas 44 to 50 degrees is normal in typical cams. LSA was a very wide 114 degrees or thereabouts.

The cam card for one has .005" durations at 190/200* and .050" durations at 254/264*, a difference of 64* (!), with a 114 LSA.

This all would make the intake closure late despite a narrow .050" duration (to help mileage) so that you could keep the dynamic CR's down with a higher compression engine and run street gas in a 10 to 11 SCR engine. Idle was smooth, torque was especially good, and idle vacuum was 18-19".

The ramps were faster between .050" and peak lift to help keep decent lift. The down side would be that peak lift with a 1.5 rocker ratio was not as high as you have presently. A 1.6 rocker would help recover some of that. But I suspect you would still be down around .410ish intake lift with this type of cam.

I have looked for something similar in today's cam listing, and the Racer Brown EH series lobes are 'nudging' towards this idea. Maybe he could widen the LSA with one. Comp Dual Energy has a .050" to advertised duration difference above 50* but the LSA's are too narrow. (I tried one for your present combo and it did not help much.) And it would not hurt to call Crane and see if they still have their HE grinds around.
 
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nm9stheham said:
YR's idea of calling a cam grinder may be a good thing to do. I am not sure I mentioned it in this thread, but Crane had a series of cams in the 70's call HE cams (hydraulic efficiency). These were designed and sold after the 1st Arab oil embargo, so guys with hotter engines could tame it down for better fuel mileage. They had veeery slow ramps between .005" (advertised) and .050"; there was more than 60* difference between advertised and .050" durations, whereas 44 to 50 degrees is normal in typical cams. LSA was a very wide 114 degrees or thereabouts.

The cam card for one has .005" durations at 190/200* and .050" durations at 254/264*, a difference of 64* (!), with a 114 LSA.

This all would make the intake closure late despite a narrow .050" duration (to help mileage) so that you could keep the static and dynamic CR's down with a higher compression engine and run street gas in a 10 to 11 SCR engine. Idle was smooth, torque was especially good, and idle vacuum was 18-19".

The ramps were faster between .050" and peak lift to help keep decent lift. The down side would be that peak lift with a 1.5 rocker ratio was not as high as you have presently. A 1.6 rocker would help recover some of that. But I suspect you would still be down around .410ish intake lift with this type of cam.

I have looked for something similar in today's cam listing, and the Racer Brown EH series lobes are 'nudging' towards this idea. Maybe he could widen the LSA with one. Comp Dual Energy has a .050" to advertised duration difference above 50* but the LSA's are too narrow. (I tried one for your present combo and it did not help much.) And it would not hurt to call Crane and see if they still have their HE grinds around.
Click to expand...

I remember those
An excellent idea.
I'm a bit behind trying to test some of the suggestions because of the weather here but will stay on it and keep everyone posted.
 
I hear ya Jeff! I'm not so eager to be laying on my back in a cold garage and grabbing colder metal. (Though the creaper is a back saver on a few fronts)
It's just the hands aren't so happy at these temps.
 
I think it's still just a matter of tuning. I've run 185psi before with no issues on 10% ethanol. Slow down the advance, play with the power valve, and tighten the vacuum advance can two turns in.

Edit- sorry, two turns counterclockwise... or four... out, not in.
 
moper said:
I think it's still just a matter of tuning. I've run 185psi before with no issues on 10% ethanol. Slow down the advance, play with the power valve, and tighten the vacuum advance can two turns in.

Edit- sorry, two turns counterclockwise... or four... out, not in.
Click to expand...
working with vacuum advance... this doesnt work at WOT and if your getting a ping before WOT youve got some work to do
 
rumblefish360 said:
I hear ya Jeff! I'm not so eager to be laying on my back in a cold garage and grabbing colder metal. (Though the creaper is a back saver on a few fronts)
It's just the hands aren't so happy at these temps.
Click to expand...
Rumblefish360
Three words "two post lift"
With it I would have quit years ago.
 
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