Eric's cam challenge

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273

273

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I'm starting a thread on it here instead of it side tracking someone else's thread.

Images from TT5.9mag

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273 said:
Funny how varied the specs are been looking for common threads in the best and worst in the list.

The ones at the bottom of the list tend to have less exhaust duration, overlap and have lsa on the wider side. Even though there's a few examples like that in the top.

I find the 2 BTR interesting they did well hp wise but fell way short on tq, but the worst one #2 seems more inline with the top players but the smaller one #1 did better even thought the specs are less like the top ones.
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I watched the dyno days live both days at work.. man they were doing cam changes like 30 mins.. 1 pull.. rip it apart and onto the next one.. Very interesting data from it though
 
Much respect for Weingartner for putting this one together and fulfilling it. Going that hard three days in a row has to be taking a toll on his health. I don't remember the exact spec on the 408 LS, but I thought the compression ratio was high enough (I was thinking near 13:1) to dictate a lot more duration than what any of the entries had. I would have like to have seen what something in the 250 to 260 @ .050 range would do, if nothing more than at the upper rpm with the monstrous head flow.
 
Garrett Ellison said:
Much respect for Weingartner for putting this one together and fulfilling it. Going that hard three days in a row has to be taking a toll on his health. I don't remember the exact spec on the 408 LS, but I thought the compression ratio was high enough (I was thinking near 13:1) to dictate a lot more duration than what any of the entries had. I would have like to have seen what something in the 250 to 260 @ .050 range would do, if nothing more than at the upper rpm with the monstrous head flow.
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Agreed, it's a Dyno challenge...let er rip.
 
MOPARMAGA said:
Agreed, it's a Dyno challenge...let er rip.
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Yeah, and I know of at least one Gen 1 SBC (383 stroker with decent ported iron "turbo 292" heads) street car ('70 Firebird) with near 12:1 that has 257/269 @.050 .493/.512 on a 108 LSA, 3.73 gears, and a T10 and it's got "just the right amount" of camshaft.
 
Garrett Ellison said:
. I would have like to have seen what something in the 250 to 260 @ .050 range would do, if nothing more than at the upper rpm with the monstrous head flow.
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They could've if they wanted to, 7th place, Quinton had a 255/261 cam, a lot of them had 250-260 exhaust but mostly 235-245 intake.

Was there a set rpm range for average hp & tq ?
 
Top peak tq was getting 1.39 tq per cid and lowest wasn't doing too bad at 1.33 tq per cid.

DV didn't too bad on tq, 1.36 per cid, came in 8th in peak tq and 10.5th in average tq, but blew it in peak power 20th out of 23 for an overall 14 th :)
 
The worst ones (bottom half of list) beside having seemly average wider lsa and less exhaust duration and overlap, the IVO seems to generally open later and EVC close sooner. Is what trends I'm seeing, the IVC & EVO variances seems to be somewhat averagely spread out from top to bottom.
 
273,
Thanks for posting.

I could never understand what this test would prove.....& still don't.

From what I could tell, all the parameters such as LSA, duration could be anything. So what actually is being compared?
 
273 said:
Top peak tq was getting 1.39 tq per cid and lowest wasn't doing too bad at 1.33 tq per cid.

DV didn't too bad on tq, 1.36 per cid, came in 8th in peak tq and 10.5th in average tq, but blew it in peak power 20th out of 23 for an overall 14 th :)
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I'm not shocked at dv not doing well.
 
Icetech said:
I watched the dyno days live both days at work.. man they were doing cam changes like 30 mins.. 1 pull.. rip it apart and onto the next one.. Very interesting data from it though
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1 pull on each cam? No jet changes? No timing changes?
 
Seems like all the top hp ones had exhaust duration in the 250-263 ones under 250 didn't seem to do to well hp wise. The ones that had 250+ exhaust but that were in the bottom 13 places but made good hp also had 11+ IVO & EVC but had poor torque they also had IVC in the 49-51 range.
 
Garrett Ellison said:
Yeah, and I know of at least one Gen 1 SBC (383 stroker with decent ported iron "turbo 292" heads) street car ('70 Firebird) with near 12:1 that has 257/269 @.050 .493/.512 on a 108 LSA, 3.73 gears, and a T10 and it's got "just the right amount" of camshaft.
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Yeah I'm going to switch up cams in my 470 soon, it's just under cammed, new will be from bullet 275-288 @.050/ .696 - .674 custom spec by newbomb turk
vs hughes 264-268 @ .050/ .664 -.686
I'm looking to bring up my peak torque to around 5500 from 4800.
 
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Bewy said:
273,
Thanks for posting.

I could never understand what this test would prove.....& still don't.

From what I could tell, all the parameters such as LSA, duration could be anything. So what actually is being compared?
Click to expand...
You look for the trends, there is a somewhat pattern to it's seemingly randomness but in the end of the day its only one test for one engine. But does show there's probably many different ways to get there (similar results).
 
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Bewy said:
273,
Thanks for posting.

I could never understand what this test would prove.....& still don't.

From what I could tell, all the parameters such as LSA, duration could be anything. So what actually is being compared?
Click to expand...
In post #11 is what trends I see the worst ones generally have even though some of the top performers have some of the traits question is why, but generally they don't.

Post #11
273 said:
The worst ones (bottom half of list) beside having seemly average wider lsa and less exhaust duration and overlap, the IVO seems to generally open later and EVC close sooner. Is what trends I'm seeing, the IVC & EVO variances seems to be somewhat averagely spread out from top to bottom.
Click to expand...

One thing I notice ones with good hp but poor torque had similar traits in Post #15

Post #15
273 said:
Seems like all the top hp ones had exhaust duration in the 250-263 ones under 250 didn't seem to do to well hp wise. The ones that had 250+ exhaust but that were in the bottom 13 places but made good hp also had 11+ IVO & EVC but had poor torque they also had IVC in the 49-51 range.
Click to expand...
 
I didn't expect a full 50hp swing, i figured maybe 20.. that's crazy
 
Icetech said:
Nope... the contestants had all the specs, and knew how it would be run and had to design a cam around those specs.. it was interesting..
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So its really a who can guess the best camshaft suited to the parts assembled.
 
Hysteric said:
So its really a who can guess the best camshaft suited to the parts assembled.
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i wouldn't call it guessing, almost everyone in the competition is a professional engine builder using their own formulas for choosing cams. They were given every possible spec of the engine right down to the weight of the valves and retainers...
 
Everyone generally says get a custom cam, but now all a sudden it's guessing and a pointless test, obviously it's a guesstimation based on the grinder/builders experience, and bet if they did a different sets of engines the ranking would change so it's probably a bit of a crap shoot.


These seem to be the players.

1. Summit Racing.
2. Cam Motion.
3. Daniel Powell.
4. Daniel Powell.
5. Joe Carol.
6. Brent Lykins.
7. Brian Taylor.
8. Carsten kafer.
9. Lucas Simeon.
10. Brian Salter.
11. Brandon Gumaer.
12. Chris Straub.
13. Jon Elford.
14. Tim Hilliard.
15. Optimum Performance.
16. John Vitone.
17. Jacob Gibson.
18. Anonymous 1.
19. Anonymous 2.
20. Quinton Performance.
21. B&F Engines.
22. Gwatney Performance.
23. David Vizard.

"The two anonymous cams are from the same company, they just didn't want to deal with all the phone calls, and will be revealed closer to the competition which will start on 22nd October maybe 21st Erik needs to set up.

Also these are the cam grinders.....
Summit
Texas Speed
Comp
Powell
Cam motion
Crower
Btr
Mellings
Callies
Straub...I'm guessing Bullet.

Cam cards will be seen closer to the competition."
 
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