[VORTECPRO]

That barometer is awful. Odds are against you, but good luck.
So the car will retain the present torque converter that is uses for the high HP setup?
What rear gearing?

" Odds are against you"


I've heard this from a few others as well. I have a cart full of converters, so this will be optimized, the gear is a different story, 4.56 to answer your question, and I don't really want to change them, this could be a problem.

 

[WHT/73]

You think It may run out of breath with the 4.56's?

 

[artmalibu]

Considering the altitude you are accustomed to running in, my bet is you will get the goal first time out.

 

[VORTECPRO]

Yes. WOTR where are you?

 

[VORTECPRO]

Considering the altitude you are accustomed to running in, my bet is you will get the goal first time out.

Thanks, I hope so.

 

[BrocLuno]

Since there are so many PP heads out there, the idea that there can be an optimized combo for them is a great way to sell a new line of parts and services

Someday I'd like to see an optimized combo for std stern drives in boats. You can't spin those things to fast and they have mediocre exhaust flow through the leg and prop. I think this is another place where PP heads could be used with a combo that yields big TQ at 4,500 or so

 

[Alan F]

Will this use headers or manifolds? I'm interested in any thoughts about the RPM range in which the headers will provide an advantage.

 

[mr 4 speed]

IMHO,this motor will need headers to utilize the headwork effectively.

 

[WHT/73]

Yes. WOTR where are you?

Me? Jersey.

 

[BrocLuno]

So I wonder if there is a way to enhance swirl with these heads. That might allow a bit more timing...

The intriguing thing is Somender Grooves. Usually cut across the quench area and aimed at the spark plug. The theory is that in that last little bit of compression stroke, the gases in the quench are are ejected at high velocity toward the plug adding turbulence... Some guys point them towards the exhaust valves... But whatever direction they are pointed, I'm sure they add either swirl or turbulence.

In all cases I've read about, they are able to bump the timing a bit more w/o detonation

I realize this is all voodoo, but he does have a patent on this and some pretty extensive testing ...

Here's the link to his patent: http://somender-singh.com/patent/patentpage.html

 

[6426yy]

Mark, is this the same engine from 2011 or a copy of a proven combination? In an old thread it was 9.4:1 with a 770 VS carb.

 

[VORTECPRO]

Mark, is this the same engine from 2011 or a copy of a proven combination? In an old thread it was 9.4:1 with a 770 VS carb.

Same engine I've always built, they usually come in at 9.2 comp.

 

[VORTECPRO]

Flow test on the un ported 236 heads with a 2.190 intake valve installed. Its interesting to compare these flow numbers with other heads of the muscle car era.

Bad Port

.200 143
.300 205
.400 228
.500 238
.550 Done

Good Port

.200 144
.300 206
.400 238
.500 245
.550 Done

2.190 intake valve, no back cut, 4.310 bore, tested @ 28 inches.

 

[BrocLuno]

How does that stack up with stock oval port 791's ...

 

[baddbob71]

781's? you can see some stock flow specs here: http://www.users.interport.net/s/r/srweiss/tablehdc.htm

intake with stock 2.06 valve
.100 100
.200 142
.300 190
.400 217
.500 238
.600 270

 

[baddbob71]

Flow test on the un ported 236 heads with a 2.190 intake valve installed. Its interesting to compare these flow numbers with other heads of the muscle car era.

Bad Port

.200 143
.300 205
.400 228
.500 238
.550 Done

Good Port

.200 144
.300 206
.400 238
.500 245
.550 Done

2.190 intake valve, no back cut, 4.310 bore, tested @ 28 inches.

when you open up the port as large as possible I bet they pickup everywhere?

 

[novadude]

Why do the peanut ports get such a bad wrap? Looks to me like those flow numbers are pretty close to what the stock '60s Oval ports flow @ < 0.500" lift. No factory "muscle car" BBC oval port cam lifted the valves more than 0.500".

Did they ever make a small chamber version of the peanut port? Seems like a great head for 396/402 combos if they had small enough chambers.

 

[BrocLuno]

781's? you can see some stock flow specs here: http://www.users.interport.net/s/r/srweiss/tablehdc.htm

intake with stock 2.06 valve
.100 100
.200 142
.300 190
.400 217
.500 238
.600 270

Yeah, my bad - typing too fast Meant 781's ...

 

[USMC_Spike]

Same engine I've always built, they usually come in at 9.2 comp.

Mark,

I'll follow along also. Wondering what your cylinder pressure do you
measure at 9.2 compression?

 

[VORTECPRO]

Mark,

I'll follow along also. Wondering what your cylinder pressure do you
measure at 9.2 compression?

I don't know, never checked it, and at 6400 feet it would be low.