Maniacmechanic1
solid fixture here in the forum
Takes only 230@ .050 To pull 6200 clean Pontiac 455 Top gear full load.Int 243 exh 249@.05 overlap @.05 22
vs the older 236 243 should add the extra 300-500 rpm
Takes only 230@ .050 To pull 6200 clean Pontiac 455 Top gear full load.Int 243 exh 249@.05 overlap @.05 22
vs the older 236 243 should add the extra 300-500 rpm
112°W
What is the LCA on your old cam ?
What headers do you have again ?
496 Is like a Pontiac 455.
4.25 vs 4.21 inch strokes.
More cubed 496 and more to fill and scavange.
Seems like an exhaust issue.
Big Chevies love 5.000 inch collectors.
No exhaust.
5 inch exhaust Dumps or custom 5 inch .
Get the present cam specs for me. Around 5-6 pm I will run DD2000 for You.112°
37"long scavenger series 2" tubes
Ceramic coated with 3 1/2" collector
3" exhaust all the way back
That by my research on here should support 679hp.
Howard's said two options shim the springs which will be hard on lifters
Or more duration on the cam.View attachment 12115
Should behave real close to Ponch 455 and 496.My understanding from comp cams Guy
Said it had something to do with compression being 11.2 to one
Cam with 236 is better matched with 10:1
To 10.5:1 11:1 thing's start changing
And need more overlap really needs more like 83 degrees on 500ci 11.2:1
Efi 72 is max and if not for rings it probably wouldn't work
Got it.Old cam, and same heads
I sent you a Facebook message tooGot it.
Get it done and posted for you in a few hours.
At work yet.
6500 is magic number that alludes me.Driving.
Working with a Flow window of
.200-..550-.600 area. Higher lift cam would be of benefit.
I see 700-720 Hp max without using ultra high revs.
It may be the Mufflers.6500 is magic number that alludes me.
28" tire 4.11 gear 1/4 mile = 6329rpms
I've changed retainers and locks to titanium for better valve control
I've added 200 cfm to throttle body
For more air. Changed push rods exhaust push rods .150 longer intake .100 longer
Pypes 3" mandrel bent race pro mufflers they clam they flow 701 cfm each at 3"
6100 flat 6127 it falls off hard
Nothing left.
1.7 rockers
Let me know if you need anything elseIt may be the Mufflers.
I know the Flowmasters cost me some power in the past.
Race Cam so it still revved high with ease.
Trans Am guys use those Pypes Mufflers.
99 % stuck in 15's & 13's.....Long story...some have 400 CFM ported E heads.
I tried they hate drag racers that group...Pro Tour drive slow what they do.
1 Drag racer left & I taught him....From Detroit & a Real Street Racer.
He messes with them daily. LOL
Get to work soon, at home.