318 build problems & new direction

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AJ/FormS said:
Headers! That cam wants headers.Without 'em you will be sacrificing 10 to 20odd horsepower at the peak, and torque through out the rev range.
Your Scr looks to be 8.22@165psi, probably too high even for 91gas, depending on your squish dimension.With a smaller cam, 10/1 may be too much.
>I'm not a fan of the thin headgasket.I also question the use roller rockers and, the use of that cam if you never rev it past 3500; both overkill in a 3500 engine. At that rpm the 268* is just waking up, and you have sacrificed the stout bottom end that comes from installing the proper cam for your intended useage. Also that cam will not be happy without help from a hi-stall TC and 3.23s is the lower limit for it.
That cam does not have a 30* ICA, more like 60* in at 106
Even a 2bbl 240 cam has an ICA of around 50*

>Here's how to figure the ICA:
360 plus (intake duration divided by 2, less the installed centerline) less the intake duration, less 180, change sign on the calculator,equals ICA
Example 1; 360+(240/2,-110),-240,-180,signchange=50*, for a 240*/114
Example 2; 360+(268/2,-106),-268,-180,signchange=60*, for a 268*/110
Example 3; 360+(292/2,-104),-292,-180,signchange=70*, for a 292*/108

>You're confusing me. Why are you building a 6500 rpm engine, to spin it only to 3500 and saddling it with handicaps like a stock convertor and 3.23s and too much compression? This is all messed up.And why the pre-occupation with how much power will it make if you never explore that power?

Here's an idea;Try to evaluate what you really want.
Pick one only, from each line, and highlight it.
Low-rpm cruiser.Tire fryer.
One gear bomber.Zero-to-60 screamer.
Punch it at 32mph and light up the tires.
This is a DD,or weekend bomber, or street/strip,drag-racer,other?
I care about what gas I have to burn;................. not a bit,some,a lot.
Cruising at hiway speed in comfort means to me; not a bit,some,a lot
I care about fuel mileage;................................... not a bit, some ,a lot
Then I,for one, will come out of confusion,hopefully.
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Wow, so much good advice, from you and others. I forgot how much I love this site.

OK, so a bit of clarification on a few things first:

1. Comp cam card states powerband is from 1600-5800. Now, that is a bit higher than I wanted, but I already have the cam ready to go and don’t want another. Also, I have heard that combining a bit too much CR with a bit too much cam dials the extremes back, with respect to too much lope, too little vacuum, etc. Is this true? That is why I was targeting 10:1. And pumping 93 does not scare me, if that is needed.

2. 3.23 gearing is for now, but I might go a bit higher later.
3. Stock TC will be gone, looking to get around 2400 instead (forgot to mention).

As for what I am looking for, it is a weekend DD that I want the wife to safely be able to drive, but bark loud when I put my foot in it and burn rubber as needed. Oh, and most importantly, run what I brung and doing it all for dirt cheap.
 
cudaracer said:
And no I am not changing gears.
I see no reason why that 318 can't get nice torque right from idle and I bet I will be knocking on the door of 400 ftlbs peak.
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Idle to 4000 rpm max low end torque...not with 308 heads, imo, max torque could exceed the 400 number if executed well...but move peak torque outside the rpm you are saying you want it at.

I would use a 318/273 head for what you want, cut down nail head to 1.88/1.50 valves -ported to around 215-220 cfm intake 150-155cfm exh .450-.500 lift w/1.5 and use a solid cam...appropriately matched the motor should top out at 5200-5400 rpm torque maxd by 3800. It has a short stroke...
 
Put some converter in the thing. And not a 2400 either. That's not much more stall than the factory converter. More like a 3400 (or more). Here is your xe268 in a 318. Horsepower peak is at 5900 rpm. Notice the torque peak is at 4100 rpm. At 3000 rpm it is down 50 ft-lbs. Imagine how low it would be a 2500. 318 Small Block Build - How To - Hot Rod Magazine
 
My original goal may have bee torque, but not any more. At least not without stroking and on a tight budget. I now only seek what ever I can get by adding pistons to raise the CR from what is probably in the high 7's now. The combination of nearly 10 CR, zero decking, larger bore (+ 0.040") to add cubes and un-shrouding valves.....and adding that to my existing cam, DP intake and eddie carb should net me well over 300hp. I don't want added cost of machining and porting original 318 heads. My heads are ready to go.

My secondary option for a bit more power and lots of cost would be to add either of the following:

1. Headers to replace the Magnum manifolds, which I spent a lot of time porting. Cost for good E-body headers are nearly $700. IMO, that would add about 15hp at an upper RPM range that I will rarely if ever get to.

2. Roller lifters/cam would cost a little over $700, with torque benefits very early and substantially. Engine masters did a with/without comparison and I was shocked at how much was gained early, and yes, there are higher RPM benefits that I would barely benefit from. I would say roller would offer slightly more TOTAL benefit over headers, including FE and other benefits, and minus the header leaks and noise hassles.

But likely, depending on what my machinist suggests after teardown and how much money is left, I will probably just add pistons/rings/bearings as needed. Oh, and I will need that 2400 converter too.

thanks
 
cudaracer said:
My original goal may have bee torque, but not any more. At least not without stroking and on a tight budget. I now only seek what ever I can get by adding pistons to raise the CR from what is probably in the high 7's now. The combination of nearly 10 CR, zero decking, larger bore (+ 0.040") to add cubes and un-shrouding valves.....and adding that to my existing cam, DP intake and eddie carb should net me well over 300hp. I don't want added cost of machining and porting original 318 heads. My heads are ready to go.

My secondary option for a bit more power and lots of cost would be to add either of the following:

1. Headers to replace the Magnum manifolds, which I spent a lot of time porting. Cost for good E-body headers are nearly $700. IMO, that would add about 15hp at an upper RPM range that I will rarely if ever get to.

2. Roller lifters/cam would cost a little over $700, with torque benefits very early and substantially. Engine masters did a with/without comparison and I was shocked at how much was gained early, and yes, there are higher RPM benefits that I would barely benefit from. I would say roller would offer slightly more TOTAL benefit over headers, including FE and other benefits, and minus the header leaks and noise hassles.

But likely, depending on what my machinist suggests after teardown and how much money is left, I will probably just add pistons/rings/bearings as needed. Oh, and I will need that 2400 converter too.

thanks
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A good set of headers will make power everywhere. There is not an exhaust manifold in existence that would make power anywhere near a good set of headers.
 
forphorty said:
Put some converter in the thing. And not a 2400 either. That's not much more stall than the factory converter. More like a 3400 (or more). Here is your xe268 in a 318. Horsepower peak is at 5900 rpm. Notice the torque peak is at 4100 rpm. At 3000 rpm it is down 50 ft-lbs. Imagine how low it would be a 2500. 318 Small Block Build - How To - Hot Rod Magazine
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OK, I need more converter......but is there a drawback to too much?
 
yellow rose said:
A good set of headers will make power everywhere. There is not an exhaust manifold in existence that would make power anywhere near a good set of headers.
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Agreed.
My point was that the max benefit in power, will rarely if ever be seen. If memory serves, that 15-20hp is happening at 6K. I rarely get above 5K, which means about a 10-15hp gain.....at that 5K.
 
I ran a milder stock lower end 318 in an E body in my teens. Based on my experience then, and what I've gained in the years since, I see a lot of theorizing here and not a lot of reality or logic in the thought process. I'd like to hear from your builder assuming he has an approach to reach your goals.
 
cudaracer said:
Agreed.
My point was that the max benefit in power, will rarely if ever be seen. If memory serves, that 15-20hp is happening at 6K. I rarely get above 5K, which means about a 10-15hp gain.....at that 5K.
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I take this back.
Check out this manifold vs header compare.

 
One thing you keep quoting powerbands but those are based on 360 size engines.
The same cam in a 318 will act 5-10 larger especially running 360 heads and move the powerband up about 500 rpm or so.

And if your running manifolds you'll want a cam design for manifolds. Overlap don't like restrictive exhaust.
 
Thanks for the replies, here is my latest obsession and almost certain path.

MABBCO MOTORS Chrysler Dodge 5.9 360 Short Block 1970-1988 with Moly Rings | eBay

Yes, basically I am taking the advice of many, and just purchasing a 360 block, ready to go.
Anybody have any experience or opinions on MABBCO?

So the concerns I have now is interchangeability with this 360 short, with what I have in my 318.
As far I recall, I will need:
1. New oil pan
2. New driver side mount
3. New flex plate and converter
4. New crank damper

Anything I missed?

I will be finishing it with my machined 308 cast heads, XE268H-10 cam, Weiand DP and Eddie 600. No headers, just my Magnum manifolds.
 
cudaracer said:
Thanks for the replies, here is my latest obsession and almost certain path.

MABBCO MOTORS Chrysler Dodge 5.9 360 Short Block 1970-1988 with Moly Rings | eBay

Yes, basically I am taking the advice of many, and just purchasing a 360 block, ready to go.
Anybody have any experience or opinions on MABBCO?

So the concerns I have now is interchangeability with this 360 short, with what I have in my 318.
As far I recall, I will need:
1. New oil pan
2. New driver side mount
3. New flex plate and converter
4. New crank damper

Anything I missed?

I will be finishing it with my machined 308 cast heads, XE268H-10 cam, Weiand DP and Eddie 600. No headers, just my Magnum manifolds.
Click to expand...
In regards to convertor, you either need correct weighted convertor for external balance....or you can use the current convertor and buy a external balance flex plate....but you don't both unless the transmission changed to a 727 or vise versa.
 
There is a ton more to headers than just making additional power at the rpm of peak power.
As already stated, manifolds will stifle torque production through out the torque band, but specifically beginning shortly before the rpm of peak torque. Headers will let it out. A factory teener torque-peaks somewhere between 2400 and 3000.This is the rpm where all the factory parts are working at their finest. If you never revved any higher than this, you would never miss headers. But you would find it very difficult to drive your car and never go outside this zone.
The big advantage to headers comes with large period cams with lots of overlap. The overlap period can be treated as a 5th cycle, and is kindof like supercharging, in that the headers will make it possible for the engine to ingest more air than it could without them. That is their special ability.
But if you just want to make low-speed torque, there is no reason to spend a lot of money; just stuff a 360 in there with a teener cam, big-valve teener heads and any old log manifolds.A large two barrel and upsize the gears 20% and you are done. Peak torque at or near stall, revs to 4500 , maybe 5000 with springs and hogged out logs, and can tow a 5th wheel trailer all day. That's torque.

But if you are gonna rev it to 5000, then there is no reason to stay with the factory teener stuff which long done by then. Shifting at 5000 requires you pay attention to the tranny ratios. As in; if you want to accelerate very quickly to 5000 rpm, or you don't care.Or where do you need this 5000 rpm to occur at?
For instance; If 5000 is to peak at 60 mph in first gear; then you don't care about the tranny gears, you just use the first gear times the rear gear, and you're done. But if you want to get there in the shortest time possible, you will need to put down more average power during the run. This is most easily accomplished with torque multiplication.
So in the first example 60 =5000, you would use low gear (2.45),and 2.76 gears. 60 would be about 5100rpm. This is the slow way to 60.
In the second example, you would use the second gear in the tranny (1.45), and 4.56s. This would get you about 5175rpm. This is the fastest way with a specific,low rpm teener.
The first combo will want a high stall for any improvement.The second,will not need much stall at all.
If you still need to get to 60 quicker, then the next thing to do would be to increase airflow thru the engine,and the first thing to do is headers and a 4bbl ;Both together.
More quicker would need headwork, and valve lift.
Up to this point the engine has been shifted at 5000.
More quicker would be more duration,more compression, a higher stall TC a new rear gear;all four together.But now you will be shifting at some higher rpm than 5000!

Most guys start at the wrong end.And it's all too often just a cam, and all too often it is a disappointment.

The biggest grin you will ever experience, is the first ride after swapping out the 2.76s for 4.56s in your otherwise stock teener car
 
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AJ/FormS said:
There is a ton more to headers than just making additional power at the rpm of peak power.
As already stated, manifolds will stifle torque production through out the torque band, but specifically beginning shortly before the rpm of peak torque. Headers will let it out. A factory teener torque-peaks somewhere between 2400 and 3000.This is the rpm where all the factory parts are working at their finest. If you never revved any higher than this, you would never miss headers. But you would find it very difficult to drive your car and never go outside this zone.
The big advantage to headers comes with large period cams with lots of overlap. The overlap period can be treated as a 5th cycle, and is kindof like supercharging, in that the headers will make it possible for the engine to ingest more air than it could without them. That is their special ability.
But if you just want to make low-speed torque, there is no reason to spend a lot of money; just stuff a 360 in there with a teener cam, big-valve teener heads and any old log manifolds.A large two barrel and upsize the gears 20% and you are done. Peak torque at or near stall, revs to 4500 , maybe 5000 with springs and hogged out logs, and can tow a 5th wheel trailer all day. That's torque.

But if you are gonna rev it to 5000, then there is no reason to stay with the factory teener stuff which long done by then. Shifting at 5000 requires you pay attention to the tranny ratios. As in; if you want to accelerate very quickly to 5000 rpm, or you don't care.Or where do you need this 5000 rpm to occur at?
For instance; If 5000 is to peak at 60 mph in first gear; then you don't care about the tranny gears, you just use the first gear times the rear gear, and you're done. But if you want to get there in the shortest time possible, you will need to put down more average power during the run. This is most easily accomplished with torque multiplication.
So in the first example 60 =5000, you would use low gear (2.45),and 2.76 gears. 60 would be about 5100rpm. This is the slow way to 60.
In the second example, you would use the second gear in the tranny (1.45), and 4.56s. This would get you about 5175rpm. This is the fastest way with a specific,low rpm teener.
The first combo will want a high stall for any improvement.The second,will not need much stall at all.
If you still need to get to 60 quicker, then the next thing to do would be to increase airflow thru the engine,and the first thing to do is headers and a 4bbl ;Both together.
More quicker would need headwork, and valve lift.
Up to this point the engine has been shifted at 5000.
More quicker would be more duration,more compression, a higher stall TC a new rear gear;all four together.But now you will be shifting at some higher rpm than 5000!

Most guys start at the wrong end.And it's all too often just a cam, and all too often it is a disappointment.

The biggest grin you will ever experience, is the first ride after swapping out the 2.76s for 4.56s in your otherwise stock teener car
Click to expand...

Thanks for the detailed response, and all this would make more sense if someone can explain to me how I can make my automatic shift at any shift points I like? I confess complete ignorance regarding automatics. I did install a mild shift kit in my 904, and if I floor it at the intersection, it is shifting into 2nd real quick every time, like at 2500. I barely get through the intersection, and it upshifts. I would love to be able to shift much later, because that is where my cam will be. And simultaneously, I would love for it to gently shift into 2nd and early when I am at part throttle.
 
There is no sense whatever in putting a HIGHrpm cam in a mid rpm engine. In fact, the car will just be slower than if it had a mid rpm cam.

So if that is why you talk about a 5000rpm shift, then that needs to be addressed first. This is not a big deal. It just requires re-engineering the tranny pressures. As mentioned, you need to install a shift kit, and perhaps some governor work.
I like the TFII kit, installed with the semi-automatic directions. This way when you put it in Drive, it works just like normal except with firmer slightly higher rpm shifts.But when you manually shift it,you can hold it gear until the rods exit the engine,lol.Well that's not likely to ever happen, but it's funny to imagine.
 
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OK, so when people talk of shifting their automatic, they are talking about starting in low 1 and shifting to low 2 and then D. Correct? I never really do that. I rarely do that.
 
cudaracer said:
OK, so when people talk of shifting their automatic, they are talking about starting in low 1 and shifting to low 2 and then D. Correct? I never really do that. I rarely do that.
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You need to change your sig then,lol

Try this remove the linkrod from the carb to the bellcrank,under the hood. Then from under the car, pull the little lever all the way back as far as it goes. The last inch or so, should have some springiness to it. If it does, tie it up back there to something on the tranny that does not move. Now go for a ride, and report back.

BTW
all the valve events can be determined from just the durations and the LSA, and the installed centerline.
In other words, if you have 268/276/110 in at 106 you are all set. You can still figure them without the installed, you just invent your own advance number. The bare minimum to figure the events would be 268/276/110
 
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cudaracer said:
Completely forgot about the kickdown adjustment.
Thanks.

Soooo, anybody have any thoughts on MABBCO Motors?
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Sounds like a production engine rebuilder. I never would say to use one. Go find a local machine shop that actually employs machinists. Do not step over a dollar to pick up a dog turd.
 
lomchivok said:
Mabbco
BBB Business Profile | MABBCO Motors | Reviews and Complaints
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I've been in the PER business. I'm not proud of it. In fact, I'm sure it took years off my life. Almost every morning I threw up in the shower. I lost my hair in the shower. It looked like a cat fight in there. They did **** I would NEVER do. The warranty is designed to absolutely **** the customer. Every loop hole, every nick nack bullshit deal and they would absolutely bend the customer over and lay it to them dry.

I moved to management, which made it worse. most of the people there weren't machinists. They were dudes off the street that were taught to run a machine. They had no idea why they did something, or why they shouldn't. 90% of these production engine rebuilders are ****.

I almost never mention my time in the PER business. I detested it, what they did and what they do. We straight out fucked people.

STAY AWAY FROM PER's.

And that is the last I will mention about that part of my past.
 
Your postings make my day (it's actually morning over here) on a regular basis. LIKE.
 
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