Dyno test predictions
Instructor
Joined: Jan 2013
Posts: 167
Likes: 0
From: Battle Creek MI
The only changes to my 66,000 mile stock L-82 4 speed are:
Holley 4175 650 CFM Qjet replacement-no changes to jetting-softest vacuum secondary spring
Comp cams roller tipped 1.5 rockers-no difference from stock
2.5 dual exhaust and McJack's Shorty headers-Monza turbo mufflers
No pollution control
stock dual intake air cleaner assembly with K&N filter
175 degree operating temperature versus stock 220 temp
I figure about 45-50 RWHP increase over totally stock 1978 L-82!
Racer
Joined: May 2012
Posts: 354
Likes: 0
yeah you might read that from a vendor..............>
down
Racer
Joined: May 2012
Posts: 354
Likes: 0
And don't forget.............>
however real world results are different. I've changed from the stock to the roller tip to the full rollers I've NEVER seen more than a 10-15hp difference there ON the dyno, and more of that gain is in the upper rpm range, and I'd be careful on what roller rockers I would use have seen many "cheap" rollers come apart and the little needle bearings in them causing catostrophic engine damage. And at $300.00 plus dollars for a GOOD set that at much hp, however I am forced to live on a low income so $$$ are an issue for me. down
down
Instructor
Joined: Jan 2013
Posts: 167
Likes: 0
From: Battle Creek MI
I think you read WAY more into my post than what I was actually trying to convey. All I meant was that the ratios of OEM stamped rockers are unreliably reported at best, and there are aftermarket companies who specialize in controlling that ration down to the hundredth (or so they say). a 1.52 is certainly going to perform better than an OEM 1.5 that's really 1.3 due to manufacturing conditions. And that's true whether it's stamper, roller tip, or full-zoot roller "everything" 
Point being, saying installing 1.52 roller tip rockers is the same as stock is misleading.
Point being, saying installing 1.52 roller tip rockers is the same as stock is misleading.
Racer
Joined: May 2012
Posts: 354
Likes: 0
Your right........>
I think you read WAY more into my post than what I was actually trying to convey. All I meant was that the ratios of OEM stamped rockers are unreliably reported at best, and there are aftermarket companies who specialize in controlling that ration down to the hundredth (or so they say). a 1.52 is certainly going to perform better than an OEM 1.5 that's really 1.3 due to manufacturing conditions. And that's true whether it's stamper, roller tip, or full-zoot roller "everything"
Point being, saying installing 1.52 roller tip rockers is the same as stock is misleading.
Point being, saying installing 1.52 roller tip rockers is the same as stock is misleading.
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Racer
Joined: May 2012
Posts: 354
Likes: 0
SuperBuickguy is right............>
waiting for a rollback.
Racer
Joined: May 2012
Posts: 354
Likes: 0
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
How long does a dyno pull last? I can't believe it's longer than a run down a 1/4 mile track. If you can't make more than 3 runs or pulls without scattering parts, should you be there at all?
Racer
Joined: May 2012
Posts: 354
Likes: 0
we will pull em till you say stop........>
and not too many failures on it just ....sometimes? the human factor, parts suspect, etc. the most pulls made I've been were around 11, guy wasn't satisfied? trying to get 500hp out this SBC because SOMEONE or he read SOMEWHERE told him he was supposed to get that? unacheivable amount w/ his engine.
there is a limit w/everything.
