Missed on this combo?

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You said it didn't like above 30* i assume that you tested this on the dyno? Is it possible you needed better octane of fuel to get above 30* Also what altitude do you live at, or the dyno was at.
My 408 12.75:1 compression with RHS 2.02 head with a tight Quench, wants 36 total and 22 initial @ 6600 feet with racing fuel.
Is it possible that you were getting into destination and didn't like more timing? aka need a higher octane fuel...........
Even with a super efficient combustion chamber,and i don't think you have one. 30* total seems way low.
Alu head tend to want more timing, than a cast iron head. RHS head are cast iron.
 
Cudafever said:
You said it didn't like above 30* i assume that you tested this on the dyno? Is it possible you needed better octane of fuel to get above 30* Also what altitude do you live at, or the dyno was at.
My 408 12.75:1 compression with RHS 2.02 head with a tight Quench, wants 36 total and 22 initial @ 6600 feet with racing fuel.
Is it possible that you were getting into destination and didn't like more timing? aka need a higher octane fuel...........
Even with a super efficient combustion chamber,and i don't think you have one. 30* total seems way low.
Alu head tend to want more timing, than a cast iron head. RHS head are cast iron.
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We're around 1000 ft above here. And the fuel issue is just another thing I was thinking about. Race gas and 33-35 degrees... right now I'm questioning everything.

Can't believe I forgot to check cranking compression. Of all things....and I can't believe my machinist didn't mention it to me. I think we were both just a bit shocked.

I can get back on the dyno pretty cheap. Might be a good idea before I started tearing things apart. If this thing had made 580 with a little more grunt down low, I wouldn't even have questioned it.

Might throw it back on the stand and check valve events. Another thing I shoulda done. Degreed it and just figured Bullet can't make a mistake so called it done.
 
Ironmike said:
We're around 1000 ft above here. And the fuel issue is just another thing I was thinking about. Race gas and 33-35 degrees... right now I'm questioning everything.

Can't believe I forgot to check cranking compression. Of all things....and I can't believe my machinist didn't mention it to me. I think we were both just a bit shocked.

I can get back on the dyno pretty cheap. Might be a good idea before I started tearing things apart. If this thing had made 580 with a little more grunt down low, I wouldn't even have questioned it.

Might throw it back on the stand and check valve events. Another thing I shoulda done. Degreed it and just figured Bullet can't make a mistake so called it done.
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If you don't get back to the dyno you will always question this in the back of your mind. Construct a game plan and stick to it.
Bring your compression tester, race fuel, headers with a 3" collector, different carb. Your engine isn't that far off and the curve has normal traits but what I don't like is that engine can't "clear its throat" until 4400-4500 for some reason. Cam and headers is where I'd look. Open the lash and see what happens. Record cranking compression before and after adjusting lash. Good luck and thanks for sharing BTW. J.Rob
 
RAMM said:
If you don't get back to the dyno you will always question this in the back of your mind. Construct a game plan and stick to it.
Bring your compression tester, race fuel, headers with a 3" collector, different carb. Your engine isn't that far off and the curve has normal traits but what I don't like is that engine can't "clear its throat" until 4400-4500 for some reason. Cam and headers is where I'd look. Open the lash and see what happens. Record cranking compression before and after adjusting lash. Good luck and thanks for sharing BTW. J.Rob
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^^^^^^^I agree with all this. Plus, unless your headers won't fit the dyno you need to test with the headers you run in the car. I would also like to see what happens when you use a 3 inch collector. I'd also like to see 1.875 with a 3 and a 3.5 and see how it goes.

You will never know until you test. I'd like to see you tighten the lash up some and retard the cam. It's your time and money but what you learn is worth it.
 
Well the panic has left me and now I can think straight.

Sat down with the dyno sheets and compared them to a motor I built for a buddy in 2013. Very similar other than his heads were ported RHS he bought used at Carlisle.

I think mine is 60-75 ft lbs short at 4000. And I really think it should make 585 or 590 HP around 6600.
So my plan is

1. Beg borrow or steal a flywheel and check cranking compression here in my garage. Have an extra starter and the original bellhousing. Flywheel we used on the dyno is now in my buddy's Dart.

2. Check all the timing events. I THINK I can do this with the damper and my indicator on the pushrod.

3. If all looks GOOD, I will open it up and retard the cam. Have a sneaky suspicion I might find the cam is not quite right. I mean even if Hughes advertised numbers are exaggerated by say......25CFM, it should still run better than it did. Just don't think the heads are the problem.

4. After the above 3 things, I have no idea where I'll go. To be honest with ya at this point I'm HOPING the cam is off. At least then I have a direction to go...
 
Did you not degree the cam when you built the engine?

I hope you put it back on the pump after you make some changes.

Also hope to see the cranking numbers but I don't put much faith in them.
 
Looks to be giving up a bit early. I think your on the right track with knocking the cam back a few degrees and maybe a bigger carb. Are you jetting for A/F? That's just a tool, I would jet it until it looses power than back it off. Also carb spacers (can sometimes) do wonders, it may be what that intake needs to straighten out the air flow and turn it on. I know you don't plan on running one but the idea of a Dyno session is to literally try things to see what the motor responds too. How about the Dyno itself? Is it noted for being conservative? those are a rare commodity anymore with some of the numbers I see guys tossing around but, they do exist.
 
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I did degree the cam of course! I did not however check all the timing events. Like I said got it to 104 and called it a day. Didn't feel like I had to check valve opening and closing degrees. Had a lot of faith in Bullet.

The first time I scheduled dyno time about 5 years ago, the owner told me "this ain't no happy dyno". " We work on race cars." He gets it calibrated when you're supposed to and from what I hear, the numbers pretty much match the ET'S.

I will get it back on the pump. I HAVE to find something out of wack. If not, might just try retarding the cam.
But I'm getting way ahead of myself.........
 
IMM Engines built a 414 SBM a (little) while ago IIRC, with a hydraulic roller of very similar specs and ported Edelbrock heads that crested the 600 mark.
 
Ironmike said:
Well the panic has left me and now I can think straight.

Sat down with the dyno sheets and compared them to a motor I built for a buddy in 2013. Very similar other than his heads were ported RHS he bought used at Carlisle.

I think mine is 60-75 ft lbs short at 4000. And I really think it should make 585 or 590 HP around 6600.
So my plan is

1. Beg borrow or steal a flywheel and check cranking compression here in my garage. Have an extra starter and the original bellhousing. Flywheel we used on the dyno is now in my buddy's Dart.

2. Check all the timing events. I THINK I can do this with the damper and my indicator on the pushrod.

3. If all looks GOOD, I will open it up and retard the cam. Have a sneaky suspicion I might find the cam is not quite right. I mean even if Hughes advertised numbers are exaggerated by say......25CFM, it should still run better than it did. Just don't think the heads are the problem.

4. After the above 3 things, I have no idea where I'll go. To be honest with ya at this point I'm HOPING the cam is off. At least then I have a direction to go...
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Good plan, Let me know if we here at Crower can fix it if its wrong or want us to tell you what the cam really is if its wrong.
 
dart19666 said:
Good plan, Let me know if we here at Crower can fix it if its wrong or want us to tell you what the cam really is if its wrong.
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You don't think his cam is too short on duration, at least on the intake side? That's why I said to retard it. With the duration too short and the ICL so early it can't fill the cylinder once it goes past 3000 or so. If he retards is, the piston will be further down the hole, hopefully creating a greater pressure drop.

I'm not a big fan of not enough duration on the intake, adding duration to the exhaust and then opening the the LSA to move the power curve up.

IMO, the OP needs more time to fill the cylinder.
 
yellow rose said:
You don't think his cam is too short on duration, at least on the intake side? That's why I said to retard it. With the duration too short and the ICL so early it can't fill the cylinder once it goes past 3000 or so. If he retards is, the piston will be further down the hole, hopefully creating a greater pressure drop.

I'm not a big fan of not enough duration on the intake, adding duration to the exhaust and then opening the the LSA to move the power curve up.

IMO, the OP needs more time to fill the cylinder.
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I can cam doctor it because most problems like this come form a cam that was made incorrect
.
 
dart19666 said:
Good plan, Let me know if we here at Crower can fix it if its wrong or want us to tell you what the cam really is if its wrong.
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Thanks Shane! Nice to know you're on board here........and a Mopar guy at CROWER! Who'd a thunk it?

Have some time to check things tomorrow. Can't do a darn cranking compression yet but I'm checking lift at every retainer. It's a start.
 
yellow rose said:
You don't think his cam is too short on duration, at least on the intake side? That's why I said to retard it. With the duration too short and the ICL so early it can't fill the cylinder once it goes past 3000 or so. If he retards is, the piston will be further down the hole, hopefully creating a greater pressure drop.

I'm not a big fan of not enough duration on the intake, adding duration to the exhaust and then opening the the LSA to move the power curve up.

IMO, the OP needs more time to fill the cylinder.
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Well if I can't find a glaring problem I am going to retard it back to 108 and head back to the dyno. Dont know if 2 degrees will do much. What are your thoughts on this, YR?
 
Ironmike said:
Well if I can't find a glaring problem I am going to retard it back to 108 and head back to the dyno. Dont know if 2 degrees will do much. What are your thoughts on this, YR?
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Looking at your dyno numbers, the intake valve isn't open long enough. You can help this by closing it later. Also, I think the 108 LSA may be hurting you a bit from 3000 to probably peak. When I think of your combo, I'd like to see more duration on the intake. I don't think there is any advantage to a dual pattern cam in your situation. Like I've said before, are they adding exhaust timing or reducing intake timing? Looks like they had reduced intake timing. You are trying to fill more cylinder volume through port architecture developed in the late 1950's for a low 300 CID engine with a max RPM of maybe, MAYBE 5500 RPM. The only option is to open the valve longer.

The LSA is also not helping at overlap. I'd think for what you have you need an ICL of 108-110. It needs to be that late to help fill the cylinder.

My best guess is 269/269 at .050 and I'd leave the lift alone so you don't have to screw with the geometry. Then I'd say a 104 LSA, in at 102 if you have a timing chain, 103 with a belt and 104 with a quality 3 gear drive.

I *THINK* there is 40-45 HP left in correcting the cam. 25-30 HP in it if you are just going to move the ICL to 108-110.


This is why I was never big on posting a customer dyno sheet unless they asked me to. The cheap screws, like parasites never pay to flow their heads, or dyno their engines. They just suck off what people post. You've already spent a pretty big sum to get where you are, and now you are going to be spending more looking for more HP. It's a viscous circle. And it lives and breathes 100 dollar bills like penny candy.

Like I say, I *THINK* there is more to be had. Just depends on what you want to spend. And don't forget the time element.
 
Your fist post says the cam is in at 104? Is it 104 or 106?

I don't mess with 1 degree unless the customer is paying for it. 1 degree is picking the pepper out of the fly poop.

BTW, it's been my opinion since 1985 that if you have to move the ICL one way or the other much off of the LSA you have the wrong cam.

My buddy, on several napkins at Burger King drew it out for me and it made sense when you look at all the events.

Should have kept those napkins.
 
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Well today I had time to check some things and here's what I come up with.
First thing I did just to make things were even was to adjust all valves to .010 lash. Then....
Measured lift at every retainer with a dial indicator. Stable and nice and straight. Every valve had .614 to .616 lift.

So next I pulled the passenger side rockers off and set up my indicator right on the pushrod. I just did 2 cylinders and it kinda tough to get perfect geometry, but you can see in the picture, I came up with .4090. Supposed to be .4175 according to my card so I think it's probably ok. I think.

What's not ok is my rockers.
If you take the .010 lash and ad it to the .616ish that I measured you get .626. EXACTLY what a 1.5 rocker should give you. Problem is I bought 1.6 rockers and they a marked as such. I think my rockers are off.

I spent a lot of time checking....making sure my indicator was positioned right. Came up .626 every time.

Should be .4175 X 1.6= .668. So If I am right, I wonder how Hughes will respond.

.040 lift short has to be worth something on this motor.

And now I don't think I like the cam. Geezus
 
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response will be that you need to check the lift at the cam lobe, not the Pushrod. The lifter to pushrod is not straight. don't know how much you give up, with the the two angles, but you have to loose some.
 
Cudafever said:
response will be that you need to check the lift at the cam lobe, not the Pushrod. The lifter to pushrod is not straight. don't know how much you give up, with the the two angles, but you have to loose some.
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Agreed but still should have advertised lift at the valve, correct? So I lost some at the pushrod. .409 X 1.6=.654. I got .626
 
the pushrod and the lifter are in a different plane....it is something like the cos11 degrees x the gross lift at the valve..
 
These are the problems in life I want !!

But I think if I stop posting and keep reading I might learn something new...
now everyone hit the agree button
 
pushrod angle is figured in to cam specs. advertised valve lift is just as said. Lift at valve, of which mine is short. I think rockers are NOT right.
 
Ironmike said:
Agreed but still should have advertised lift at the valve, correct? So I lost some at the pushrod. .409 X 1.6=.654. I got .626
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The .010" lash will change the valve lift by the lash x the rocker ratio. So you should be adding .016" to the measured lift in your computations.

Just to check the geometry correction: Look at roller position on the tip of the valve right at exactly mid-lift point. If the geometry is as good as it can be, then the roller will have moved as far out on the valve tip right at mid lift, and will roll back in across the tips about equal amounts at both at full open and full closed. It may not be exactly this but should be close.

I can't see .040" short on valve lift being just from the pushrod angle. The 'cos 11* x .409" tappet lift' works out to .4014" and multiplied times 1.6 is a loss of .012" at the valve. So there is more going on. Know that, even with geometry correction, there will be some loss in lift due to the rocker rotating through a very wide angle; your lifts are getting so high for the rocker length that it is reaching the point where the unusually large rotation angle starts to result in significant loss of vertical motion.
 
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nm9stheham said:
The .010" lash will change the valve lift by the lash x the rocker ratio. So you should be adding .01^ to the measured lift.

Just to check the geometry correction: Look at roller position on the tip of the valve right at exactly mid-lift point. If the geometry is as good as it can be, then the roller will have moved as far out on the valve tip right at mid lift, and will roll back in across the tips about equal amounts at both at full open and full closed. It may not be exactly this but should be close.

I can't .040" short on valve lift being from the pushrod angle. The 'cos 11* x tappet lift' works out to
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Hey ya didn't finish your post..... "works out to" what? Please elaborate.......

I have the B3 geometry correction kit. My rollers don't roll out or in at all. Geometry is perfect.
 
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