[racerboy]

Originally Posted by napster

Jhein & Racerboy,

I don’t know if this will help you, but here it goes.

A few years ago, I purchased a 1970 T/A that had a service replacement block. The person I bought from had the engine rebuilt and replaced the #12 heads with RA IV #614 heads. After I bought the car, the engine had to be rebuilt with less than 100 miles on it.

I decided to have the engine rebuilt with a 427 stroker kit and with the .030 overbore now have a 433 CID engine. The engine was dyn’d but I only got uncorrected numbers. 447 HP @ 5000 RPM and 535 TQ @ 3500 RPM. I figure the corrected numbers are 460 HP and 545 TQ. Compression is 9.9 to 1. All of this runs thru the oversized RAIV manifolds. My engine builder thinks long tube headers would add 30 HP.

Hope this helps.

Thanks for sharing!


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[78w72]

Originally Posted by napster

jhein,

I also have a 461 stroker in a '78. Running e-heads and long tube headers and an off the shelve comp cam XR288HR. 583HP @5500 and 623TQ @ 4200. 9.5 to 1 compression.

This might help more than the other example.

nice numbers for sure... what are some other specs if you care to share? heads proted? intake/carb? & why only 9.5:1 with alum heads?

[OCMDGTO]

Napster what rocker ratio are you using? I'm guessing more than 1.5s which would only give you .520/.540 lift. GREAT power numbers from that cam

[bird72]

Originally Posted by napster

Butler custom grind.

I run that cam in my HO. It is cold blooded till warmed up. Makes lots of power. Run with forged pistons 10 to 1, and forged rods. Run RA exhaust. I believe with good headers another 50hp is there.

[napster]

Originally Posted by jhein

Those are very impressive numbers. That's definitely more than I want or need.
How do you use that car and how are it's manners?

I'm still breaking in the engine for the first 500 miles since I got it back late in the year. So I haven't explored what this car can really do. However, what I have explored scares the heck out of me. I am going to buy a box of depends and put them in the seat next to me.

I use the car like all my cars. Mostly to and from car shows or take it out for a drive for exercise purposes. Sometimes for a trip, but that is few and far in between.

Manners? It is a beast when I put my foot into it. Since I'm breaking it in that has only been no more than 1/4 throttle. Throttle response in right away with the EFI on the car. It is very streetable as long as restraint is exercised. When I first got the car back I wasn't ready for the torque hit and almost overrun the car I was passing. The way the transmission is setup it will go right to the sweet spot of torque when the transmission downshifts. The sweet spot is 4000 RPM.

[napster]

Originally Posted by OCMDGTO

Napster what rocker ratio are you using? I'm guessing more than 1.5s which would only give you .520/.540 lift. GREAT power numbers from that cam

Thanks. Running 1.65 ratio roller rockers.

[78w72]

Originally Posted by napster

Thanks. Running 1.65 ratio roller rockers.

can you mention some of the specs of your build? curious how it reached almost 600hp & 620+tq with the parts listed & low compression... & why only 9.5:1 with alum heads?

also, since you stated exact hp & tq numbers, i assume it was dyno'd... if thats the case its pretty much as broken in as it will get, at least for ring seating etc. during dyno pulls, it was subjected to far greater forces than it will ever see on the street, you can definitely go more than 1/4 throttle with no risk of damage.

[Formulabruce]

Originally Posted by Lee

HP is misleading, even more so when dealing with motors that make much more torque than HP. People often throw away a lot of lower RPM TQ to gain a little of upper RPM HP.

What do you want the car to DO?

NO Truer words have been Ignored so many times!
Other auto brands and false " HP mentality" lead to desktop dynos and open wallets, and a happiness that doesn't last.
But yeah, ya got a piece of paper from a dyno which can only calculate HP, not measure it, and from a range starting at 3800 rpms and just skip where Pontiacs Pull, AND where you drive your car, the torque band.
I would ask do you want to drag race a road race car, or
Just play with power?
In the end, Driveability determines if your car gets used, or sits.
Imagine how good 400 ft lbs of torque feels at 2400 rpm...