Hi group. I have finally gotten to a point on the wifes 66 where I need to nail down which motor conbination to go with. The only thing I have for the motor as of right now is a set of aluminum rectangular port GM heads with 2.25 intake valves, 116cc combustion chambers and a team g single plane itake. They were mildly ported by Sonny Leonards so they should be a good head for this deal. I was going with a 496 but it is my understanding they do not make the power because of a long stroke-small bore deal. So with that, what would you guys build? The parameters for this is it is a full 66 chevelle with a richmond 4+1 (3.27 low gear), 3.42 rear gears and 1 7/8" shorty headers with 2.5 exhaust. I am running a high volume meachanical fuel pump with a sump on the tank and -8 line to the front with a bypass. The ignition is a HEI with msd box and coil. My goal was to make this car run 11.50's without killing the car and cut the A/C on as we head to outback steakhouse afterwards. Am I asking for too much or is this possible? I currently have a 454 passenger motor to use for the buildup and I want it to run on pump gas. And the use of a solid roller is fine with me. All replys are welcomed as I am debating this combo with a few people.

John Weaver

if its 11.50's you're after, I'd go 468,since you've got the block.

John,
Don't know who told you a 496 won't make power but to put it in polite words,,,, they are full of crap :D
For your goals a 468 is really all you need but the 496 is going to make more torque & power especially with the larger heads.
Even at a very conservative 1HP/Cu In you are looking at 30HP & even more in torque which is what you want for your goals of a fast reliable air conditioned driver. ;)

Originally posted by SLOPAR:
I was going with a 496 but it is my understanding they do not make the power because of a long stroke-small bore deal. John, a solid roller 468 could make your goal, the torque of a 496 makes it easier, and of course a 540 will handily get the job done.

Chevelles are heavier than a lot of other cars - torque is your friend. I have only built one 496, it is in my '65. It made a peak of 602 tq at ~ 4,800 - with 495 tq available starting at 2,500 rpm. Peak power was 640 hp at ~ 6,300 rpm.

The bigger the engine, the "milder" the build can be to meet your goal.

I've only made just a few passes in my El Camino with the 496, I expect with a little bit of tuning and changes that it will end up in the high 6.7x's in the 1/8 mile (~ 10.70 1/4 mile).

Thomas

thanks for the replys. I could have done a better job describing the power abilities of a 496. What I have been trying to figure out is my best bang for the buch and the few that I have talked to that have owned 496's said they would have done a good 468 if they had to do it over again. I spoke with one big engine vendor today (I willl not say who) and we got no further than him telling me to get 2 1/4 headers. I then talked to Ohio Crankshaft and they said to do a 548 with a retro-fit hydralic roller and that will give you the best bang for the buck. He said the Merlin block will run cooler on the street and if I ever wanted to do something bigger with this car I already had the bottom end for it. I am curious Thomas as to your combination and what the weight of your car is.

Thanks,
John Weaver

John, I don't know how many cars you have built - but a lot of the desireability of a certain combo can be very subjective. The way your topic is stated, I figure that you would probably be happiest with a big moderately built engine. My idea for a street car is to build for torque and gear accordingly. I still have a lot of parts and tuning left to do, but my original goal of a pump gas 91 octane (Cali gas sucks!) drive up high 10 second car has been met.

I think Ohio Crankshaft is giving you good advice on the 548.

I figure that my race weight is ~ 3,600 lbs, but I really need to get a current weight. The last time my '65 was scaled it registered 3,440 lbs on an uncertified scale, but that was before the 10 point cage and the deletion of unneeded parts like the heater etc.

Rest of my combo from top down:
K&N stub stack (worth 13 hp on the dyno)
Holley #8896 Dominator 1050 (soon to experiment with a reworked HP950)
Tapered reducer carb spacer adapter from 4500 to 4150
Edelbrock Victor Jr with port matching etc. (soon to experiment with an Air Gap)
* I think I might also like to try an older Edelbrock C427 or C454 intake *
Brodix BB-2's 2.25 x 1.88 valves, ported to ~ 379 average cfm intake
10.72 static compression ratio
Generic Hooker #2455 2" primary headers
Mallory HEI ignition (still need to get the advance curve to my liking)
Current cure is 28 degrees initial, 36 degrees at 3,400 rpm
Comp solid roller, net lift after lash .644/.642, duration 248/254, 110 intake centerline installed at 108
Had Carter 120 #4889 strip pump, just installed a Carter 172
Billet 200 4R trans with ~ 3,400 stall
12 bolt, 4.10 gears
Hotchkiss lower rear arms
Morrison Gazon adjustable uppers with relocation brackets
Stock springs - but seriously shortened
Koni adjustable front shocks
KYB Gas adjusts in back
No front sway bar
Was 1" rear sway bar with pass listed in sig, now has 1-3/8" rear sway bar that I hope will slightly straighten launches
M.T. E.T. Streets, 28 x 11.50 x 15

The car is a lowrider - the rear was lowered 5", the front 2"-3". Countless people have commented to me that El Caminos, and especially lowriders, dont drag race very well (I guess I like a challenge). But I'm convinced I can turn my weak 60' times, 1.57 best so far, into low 1.4x 60' times.

Oh yeah I foot brake launch just off idle.

Hope that helps, Thomas