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Re: 470 dyno test article
[Re: AndyF]
#2455046
02/21/18 01:05 PM
02/21/18 01:05 PM
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Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
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I think there might be "some" gains to be had by (as Grumpy said in his 1975 SBC book) "fiddling with the cam".
But, the fact that the motor didn't respond at all to a pretty big swing in rocker ratio changes....... I don't think there's any "easy 25hp" to be gleaned from only swapping the cam at this point.
I'd be looking towards the EM builds for inspiration as far as the cam goes.
Btw...... Did you mess with the lash?
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
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Re: 470 dyno test article
[Re: mopar dave]
#2455149
02/21/18 04:27 PM
02/21/18 04:27 PM
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Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
BradH
Taking time off to work on my car
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Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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Thats the test i would like to see results with. LSA. You can probably find a good number of LSA-type tests searching online. No real mystery, other than making sure the LSA, duration & lift actually suit the combination. Well, maybe it's a mystery to a lot of people, still. 
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Re: 470 dyno test article
[Re: AndyF]
#2455582
02/22/18 01:40 PM
02/22/18 01:40 PM
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Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
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TF 270's are fully ported OOTB.
Sure, some may be porting them more, but there are no "unported" TF 270's.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
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Re: 470 dyno test article
[Re: AndyF]
#2455594
02/22/18 01:57 PM
02/22/18 01:57 PM
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Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
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Posts: 14,491
So. Burlington, Vt.
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So, peak to peak, what was the difference between the two cams?
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
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Re: 470 dyno test article
[Re: mopar dave]
#2455598
02/22/18 02:08 PM
02/22/18 02:08 PM
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Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
BradH
Taking time off to work on my car
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Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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... Seems 108 works pretty good on a small block. Not trying to bust your chops, but 108 works where 108 is the right LSA for the combination, regardless of small block, big block, or whatever. Four of my last five BB cams have all been 108, because that's been a good choice for those combinations. If I made significant changes, I'd expect the LSA and/or duration might need to change, too. I've got a nice 109 LSA solid roller that I never tried because I didn't have the right rocker ratios on hand to show its true potential. That cam grinder wanted to put it on 110, but we split the difference on his preference for 110 and mine for 108. ... I would like to see first hand what Andy finds with that BB. I can't ready Andy's mind (nor my wife's, even though she thinks I'm supposed to be able to), but I suspect anyone who wants to send him a $1000 to offset parts / teardown / dyno expenses might "influence" what he's interested or willing to test. I've got enough first-hand experience now from multiple dyno sessions to know that stuff gets spendy fast, especially if it turns into more of an R&D session than a straight test & tune of a single combination.
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Re: 470 dyno test article
[Re: fast68plymouth]
#2455614
02/22/18 02:33 PM
02/22/18 02:33 PM
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Joined: Jan 2003
Posts: 30,989
Oregon
AndyF
OP
I Win
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OP
I Win
Joined: Jan 2003
Posts: 30,989
Oregon
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So, peak to peak, what was the difference between the two cams? Turns out I don't have a clean A to B test with the same exact parts on both engine due to the problems I had with the vacuum pump. I wasn't able to run the QRI cam with a vacuum pump since I had issues with it so all of my current testing is with breathers. The engine is making right around 750 hp with the QRI cam using breathers. I made 775 hp with the HXL cam using a vacuum pump and Wilson Indy. I made 745 hp with the HXL cam using breathers but with the M1 Wilson intake. (std port intake) I never tested the HXL cam with breathers and the Indy Wilson intake so I don't have that as a baseline. My guess is that the HXL cam with breathers and the Indy Wilson intake would hit 755 or 760 hp in an A to B test but I wouldn't be surprised to be wrong. Another thing is the weather. The last few days have had cold air so the correction factor is negative. Even thought the correction factor is only a few percent different than the previous tests, that is enough difference to throw some doubt on the comparison.
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Re: 470 dyno test article
[Re: BradH]
#2455624
02/22/18 02:47 PM
02/22/18 02:47 PM
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Joined: Jan 2003
Posts: 30,989
Oregon
AndyF
OP
I Win
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OP
I Win
Joined: Jan 2003
Posts: 30,989
Oregon
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... Seems 108 works pretty good on a small block. Not trying to bust your chops, but 108 works where 108 is the right LSA for the combination, regardless of small block, big block, or whatever. Four of my last five BB cams have all been 108, because that's been a good choice for those combinations. If I made significant changes, I'd expect the LSA and/or duration might need to change, too. I've got a nice 109 LSA solid roller that I never tried because I didn't have the right rocker ratios on hand to show its true potential. That cam grinder wanted to put it on 110, but we split the difference on his preference for 110 and mine for 108. ... I would like to see first hand what Andy finds with that BB. I can't ready Andy's mind (nor my wife's, even though she thinks I'm supposed to be able to), but I suspect anyone who wants to send him a $1000 to offset parts / teardown / dyno expenses might "influence" what he's interested or willing to test. I've got enough first-hand experience now from multiple dyno sessions to know that stuff gets spendy fast, especially if it turns into more of an R&D session than a straight test & tune of a single combination. Yeah no doubt about that. I'm fortunate to be in a position where I have the resources to do this type of testing but still there are limits. I might have the time to dink around with engine testing but people around me don't have the time so I have to respectful of them. The guy who runs the dyno has to make a living and he can't just play engines with me all day since he needs to get work out the door in order to feed his family. Given that, I can only squeak in some dyno testing "fun" about 4 or 5 times a year. So I have to pick and choose what I'll test.
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Re: 470 dyno test article
[Re: AndyF]
#2455636
02/22/18 02:57 PM
02/22/18 02:57 PM
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Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
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Did you A/B the vacuum pump last time, so you have a pretty good idea on what that was worth?
Sounds like you're thinking 10-15hp.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
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Re: 470 dyno test article
[Re: BradH]
#2455710
02/22/18 05:10 PM
02/22/18 05:10 PM
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Joined: Jan 2007
Posts: 8,031
Mt Morris Michigan
mopar dave
master
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master
Joined: Jan 2007
Posts: 8,031
Mt Morris Michigan
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David Vizard has a graph for selecting lobe sep angles. He says its the best way to do it as he finds more power in big blocks than most anyone else. I have never seen anyone use it. Looking at his graph shows my 511 would need a lob sep of 100*. I have never seen anyone use a cam with those kind of lobe sep angles. Anyone know if Vizards gragh is BS or is there some validity to it. I am assuming his engines are race only.
Last edited by mopar dave; 02/22/18 05:12 PM.
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