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Re: Anyone ever go faster with less lift?
[Re: Brad_Haak]
#3017350
02/21/22 12:51 PM
02/21/22 12:51 PM
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Joined: Jan 2003
Posts: 19,612
Las Vegas
Al_Alguire
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 19,612
Las Vegas
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Must be cold back east  Winter is silly season afterall
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: Anyone ever go faster with less lift?
[Re: Al_Alguire]
#3017351
02/21/22 12:52 PM
02/21/22 12:52 PM
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Joined: Dec 2021
Posts: 1,404
Loudoun County, VA
Brad_Haak
pro stock
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pro stock
Joined: Dec 2021
Posts: 1,404
Loudoun County, VA
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2021 Challenger 6.4L Scat Pack 1320
100% stock: 1.680, 11.894 at 113.75 (DA 175 ft)
weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)
1973 Challenger 452 ci street/strip [2008]
pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)
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Re: Anyone ever go faster with less lift?
[Re: ZIPPY]
#3017359
02/21/22 01:06 PM
02/21/22 01:06 PM
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Joined: Nov 2009
Posts: 3,082
St. Paul , Mn.
tubtar
master
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master
Joined: Nov 2009
Posts: 3,082
St. Paul , Mn.
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Can't we all just get along? Apparently not today. Tomorrow don't look so good either............ 
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Re: Anyone ever go faster with less lift?
[Re: DoubleD]
#3017372
02/21/22 01:50 PM
02/21/22 01:50 PM
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Joined: Oct 2007
Posts: 4,219
New York
polyspheric
master
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master
Joined: Oct 2007
Posts: 4,219
New York
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It's a natural occurrence.
When enough ill-mannered people find their comic-book knowledge corrected by someone they don't like, their only recourse is personal insults.
Helpful hint: in the most amazing coincidence, pointing out where I'm wrong is almost always: they didn't understand what I wrote.
Find my comments on Barton's hemi rockers. AFAIK not one person saw what I pointed out: Barton's geo is not perfect, the question was "is it enough to be important"?
[carrier wave]
Boffin Emeritus
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Re: Anyone ever go faster with less lift?
[Re: polyspheric]
#3017504
02/21/22 08:27 PM
02/21/22 08:27 PM
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Joined: Jan 2003
Posts: 10,155
Frostbitefalls MN (Rocky&Bullw...
gregsdart
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 10,155
Frostbitefalls MN (Rocky&Bullw...
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Considering this topic has spread like the bottom of a fat lady taking a seat, i will expound on my infinate wisdom, or lack there of.
#1. We don't know what we don't know. It seems we know even less when we challenge others.
#2 No rule is ever perfect.
With these thoughts in mind , i offer the following.
The best we can come up with are trends, because it seems there are always exceptions.
Case in point; i was told by someone from Indy cyl heads to NOT run over .825 intake lift with -385cnc-13 heads. Ok, why? Something about the flow goes negative at about that point? (Can't remember the reason)
So my cam with .868 lift would be wrong, correct? Maybe, i don't know. They base thier comment on 350 motors built with those heads. Maybe they are right,,,,,,BUT, nobody has infinately tested all the possible changes to all the possible combinations, including porting, bore size,add infinitum. And that cam made VERY good power in my 550 inch 440-1 motor. So, i keep looking for trends, from lots of sources.
And finally, to ALL, have a nice day, and thanks for your input 🤕😁
8.582, 160.18 mph best, 2905 lbs 549, indy 572-13, alky
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Re: Anyone ever go faster with less lift?
[Re: gregsdart]
#3017555
02/21/22 10:20 PM
02/21/22 10:20 PM
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Joined: Oct 2007
Posts: 4,219
New York
polyspheric
master
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master
Joined: Oct 2007
Posts: 4,219
New York
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nobody has infinately tested all the possible changes to all the possible combinations
This^^^!
IMHO one of the most important errors in reporting test results, few even mention "We have not the time or resources to explore all possible variants of spark, jetting, spacer height, ICL, etc. which may have provided even better information. What you just read is not really instructions to be followed, but a trend which may prove useful on your project".
Boffin Emeritus
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Re: Anyone ever go faster with less lift?
[Re: gregsdart]
#3017776
02/22/22 03:49 PM
02/22/22 03:49 PM
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Joined: May 2011
Posts: 4,492
northern,Ohio,USA
Clanton
master
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master
Joined: May 2011
Posts: 4,492
northern,Ohio,USA
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Considering this topic has spread like the bottom of a fat lady taking a seat, i will expound on my infinate wisdom, or lack there of.
#1. We don't know what we don't know. It seems we know even less when we challenge others.
#2 No rule is ever perfect.
With these thoughts in mind , i offer the following.
The best we can come up with are trends, because it seems there are always exceptions.
Case in point; i was told by someone from Indy cyl heads to NOT run over .825 intake lift with -385cnc-13 heads. Ok, why? Something about the flow goes negative at about that point? (Can't remember the reason)
So my cam with .868 lift would be wrong, correct? Maybe, i don't know. They base thier comment on 350 motors built with those heads. Maybe they are right,,,,,,BUT, nobody has infinately tested all the possible changes to all the possible combinations, including porting, bore size,add infinitum. And that cam made VERY good power in my 550 inch 440-1 motor. So, i keep looking for trends, from lots of sources.
And finally, to ALL, have a nice day, and thanks for your input 🤕😁
I recently viewed a David Vizard video where he stated the flow in the port will go negative because the lift takes away from the short side flow after the flow gets to much in the other side of the port.
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Re: Anyone ever go faster with less lift?
[Re: mopar dave]
#3017852
02/22/22 08:01 PM
02/22/22 08:01 PM
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Joined: Jan 2003
Posts: 6,187
Melbourne , Australia
LA360
master
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master
Joined: Jan 2003
Posts: 6,187
Melbourne , Australia
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I have worked in research for almost 10 years now. Some of the adademic staff I work with will postulate over theories for an eternity. Others will give it some thought and we will conduct a series of experiments and we will reevalutate from there. Point being, the later gets more meaningful work done.
Test the 1.5:1 rockers and evaluate the results. The reality is it may make little difference to your performance, but you'll learn something along the way.
Alan Jones
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Re: Anyone ever go faster with less lift?
[Re: mopar dave]
#3017888
02/22/22 09:55 PM
02/22/22 09:55 PM
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Joined: Jan 2003
Posts: 10,155
Frostbitefalls MN (Rocky&Bullw...
gregsdart
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 10,155
Frostbitefalls MN (Rocky&Bullw...
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So, less lift might be beneficial? Looks like I will have to go to a 1.5 rocker on the intake side if I want to use this cam. I have been contemplating new ported -1 heads with a matched cam. Some info for your situation; my results;;;; 550 cu in, 15/1 compression, methanol injection using a Terminater tb. 440-1 heads with 2.30 int, 1.78 ex. Fully ported by RJ in Iowa, flow numbers were hi from one source(399 at . 800) less stellar from another(370?) Cam- Jones inverse flank roller , standard size core. .868 gross lift intake, .816 ex, lash ,. 019 int, .020 ex. Duration is 284/296/114 . Intake is a 3X. 2 1/4 dyno headers. Best pull was 926 hp at 7200 rpm. Power still climbing , but not much (1 or 1.5 hp per 200 rpm?) By my tests, looks like these heads like lift. But then, only three cams have ever been tried. Each one bigger, but other mods to the shortblock.
8.582, 160.18 mph best, 2905 lbs 549, indy 572-13, alky
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Re: Anyone ever go faster with less lift?
[Re: mopar dave]
#3017981
02/23/22 10:48 AM
02/23/22 10:48 AM
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Joined: Jan 2003
Posts: 31,273
Oregon
AndyF
I Win
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I Win
Joined: Jan 2003
Posts: 31,273
Oregon
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Yes, and i think most do. The -1 head has always been a great head. The E Victor, not so much. Jesse told me best thing for this head was angle milling. Brad said he gained nothing going from 1.5 to 1.6 and he uses the same heads as me. Would had same result going from 1.6 to 1.5. I have no choice now but to put a 1.5 intake rocker on it as there is not enough v/p clearance for a 1.6, so if im comfortable with .050 on intake and .080 on exhaust i run it, if not a new cam is my next step. The cam can only be degree'd at 106, either way from that there is not enough clearance its that close. In your case the question is moot since you're going to have to use certain parts for the engine to work properly. It will be what it is.
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Re: Anyone ever go faster with less lift?
[Re: mopar dave]
#3017987
02/23/22 11:09 AM
02/23/22 11:09 AM
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Joined: Jan 2003
Posts: 14,545
So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 14,545
So. Burlington, Vt.
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If you had some new -1 heads, and milled them down to the same chamber volume as your current heads..... who’s to say you’d have any more V/P clearance than you have now? Brad said he gained nothing going from 1.5 to 1.6 and he uses the same heads as me Brad has std port Victors........ and no rockers were swapped during the dyno session. It had 1.6’s on it.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
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Re: Anyone ever go faster with less lift?
[Re: fast68plymouth]
#3018007
02/23/22 11:52 AM
02/23/22 11:52 AM
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Joined: Jan 2007
Posts: 8,153
Mt Morris Michigan
mopar dave
OP
master
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OP
master
Joined: Jan 2007
Posts: 8,153
Mt Morris Michigan
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Yes, that is the reasoning on new heads. Only take off enough to get 12:1 and gain a little clearance there. What are the chambers on a -1 head in cc? I think I had .035 taken off my victors to get 12.5:1. I’m not sure of Brads circumstance, but I assumed his testing was at the track.
Last edited by mopar dave; 02/23/22 11:53 AM.
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Re: Anyone ever go faster with less lift?
[Re: Clanton]
#3018014
02/23/22 12:16 PM
02/23/22 12:16 PM
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Joined: Oct 2007
Posts: 4,219
New York
polyspheric
master
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master
Joined: Oct 2007
Posts: 4,219
New York
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Vizard has stated pretty specifically that flow during OL is far more important than suspected previously.
When heads are flowed, is that with a 12.0:1 CR domed piston below the (partially open) valves?
At full lift, there is almost no intake vacuum, while (assuming a good exhaust) at OL vacuum from the return pulse may be 7".
Flow bench: useful
Dyno: more useful
LSR: most useful
Boffin Emeritus
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Re: Anyone ever go faster with less lift?
[Re: mopar dave]
#3018037
02/23/22 01:08 PM
02/23/22 01:08 PM
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Joined: Jan 2003
Posts: 14,545
So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 14,545
So. Burlington, Vt.
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Yes, that is the reasoning on new heads. Only take off enough to get 12:1 and gain a little clearance there. What are the chambers on a -1 head in cc? I think I had .035 taken off my victors to get 12.5:1. I’m not sure of Brads circumstance, but I assumed his testing was at the track. Since Brads Victor combo hasn’t yet run in the car, the track testing he did would have been with the old combo, which used std port stage 6’s. Andy’s rocker test proved you only need what you need, and that there isn’t always going to be any magic with a rocker swap....... since he basically saw no gains by increasing the RR in that test. My friends old 13:1 Pontiac bracket motor lost a solid 15hp by swapping the intake rockers from 1.5 to 1.6(.556 to .593 lift). Played with lash, timing, jetting, spacers...... no improvement. Put the 1.5’s back on...... poof...... 15hp came back. The next year we replaced the SFT cam for a .596” solid roller....... and picked up 50hp.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
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