I choose a "new" ZZ4...because of the bones.

Four bolt mains, Forged steel crank, angle plug aluminum heads, aluminum intake... flat top pistons and good rods.

In other words all the stuff we used to lust for back in the LT1- 350 days.

Fast is a relative word these days...so where do you stop. Stock cars running in the 10's and so on. New cars are likely faster ...unless your way north of 100K on a restomod build.

I decided that old school "new" GM was more important to me....like everything else on the car, I wanted it all "as new or better" and as nostalgic as possible.

There were a couple of improvements to the old school Gen 1 engine that I didn't mind though. One piece rear main seal, high valve cover rails that keep the valve cover gaskets dry...and a nice torque/y roller cam.

....and all "with a new GM engine warranty".

You might say most of that can be said of the GMPP 383 and you would be right. (though most of the stats are from higher rpm test than the ZZ4). BUT.."everyone" has a 383...and I didn't want to be like banana, or "just one of the bunch"...so I stayed with the 350 standard stroke engine that has served us so well for so many years....and will not be outdated... ever!

Good luck...Stan

 

Well put I see it that way ,The 396 back in the day did have power thru out the power band. I drove one it was automatic The 327 running strong was also
holding up on the track and street . Good strong engine and liked the way it ran thru the gears .I remember small blocks beating big block all the time. I guess the big blocks had to be tuned right and driven correctly,and had to hook up correctly.
I even witnessed strong 283 beating 327s
In High school the first muscle car I rode in was a 1964 GTO never forget it.

 

The first Corvette I ever drove was a '67 427 tripower 400HP coupe, with a 4 speed. This was 1985, and the car was an original owner, 26,000 mile car, all original. The guy had me install new shocks on the car before he gave it to his 21 year old son for a birthday present. It was red on red with a black stinger. Paint a little faded, but otherwise immaculate. That car made my tripower 4 speed '65 GTO seem a bit anemic....it flat out flew. I did not abuse the car out of respect, but man, what a kick it had. The guy gave the car to his son, and hopefully it didn't end up wrapped around a pole. I'm still driving that same '65 GTO....and it will beat up on my 383 powered '61 Corvette pretty good. Big block engines have a lot of torque, and that's what pins you to the seat. That said, a nice warmed up small block is just the ticket for a little 2 seater fiberglass sports car.

 

What kind of valve problems? I have not heard that complaint before nor does my experience bare that out. I used to hit 6500 rpm on a pretty regular basis.

 

This is not true. The difference between a big block C2 and a small block C2 in the handling department is nil. I've had both and driven both back to back. Besides, if handling is what you are looking for, sell the Corvette and buy a Formula Ford.

 

This is true and the first question I'm asked every time I go out. A 427 would be my preference and I have an inquiry in to Remanufactered.com. Any experience with that site? Know of any others? Thanks for the budget friendly advice!

Thank you to everybody for all the great ideas, personal experiences and research resources. I will update this thread with my decision (and I got a lot of deciding to do) when the project gets going. Still doing my R&D.

 

The big block carries the same weight over the front wheels as the small block? Learn something every day, though I have to say I can't see it.

 

So did I..

However it was common knowledge back in the day the big blocks were prone to have cams go flat because of high valve spring pressure. (or that was the reasons they stated back then).

My first exposure to this was a cam replacement on a 1969 SS-396 with less than 45K on the engine (under warranty).

I had a several lazy big blocks that only needed a new cam ( stock) to get them running good again, in the years that followed.

I always attributed that to some folks opinion that the stock big blocks wouldn't keep up with a small block.

There's no bigger slug than a stock big block with a worn cam.

Stan

 

What Stan just said. Primarily, I've run into sticky valves, and flat cams. As well as oil burning. Just going off of the several thousand BBC's and SBC's I've performed service work on over the past 4 decades. Overall, with GM engines in general built from '60-'85, the most reliable were the Olds and the SBC.....the least reliable engines have been Cadillac for the past 45-50 years, continuing on to this day, or at least through the Northstar era. Still can't believe a Big Block 'vette carries no weight penalty over a Small Block car....will have to research it.

 

Well, it looks like the big block carries 177 pounds more weight than the small block car.....for 1967, it's 3163 for the sbc car, and 3340 for the big block car. Just about all of t his weight is above the front wheels. No way would this not affect handling. Simple physics. I stand by my statement that a small block powered car is a better balance for a street driven car, where cornering is a concern. Drag racing, not an issue.

 

True just look at the stats on 2008 Corvette coup compare to the 2009 turbo charged coup at the German proving grounds. Motor Trend
The weight of the turbo was hurting the handling where the 427 got better times for being balanced .
Turbo had more power but didn't handle as good.
I can see where the front of the 67 showed the weight of the big block
even with the beefed up stock springs.

 

It is not just the 177 pounds, it is 177 pounds in the wrong place making it worse. For drag racing as mentioned, not a problem except on launch.
When we used to hit the Wednesday night drags for fun they allowed a ride along, person in the passenger seat. It would cost us a couple tenths on the run when we allowed a ride along. We were skinny back then, less than 170 lbs.

 

The balance and handling needed for good street handling vs good gymkhana handling are two different things. There are different sway bars used between the small and big block cars as well.

What ever handling that may be lost with the big block is more than made up for when you floor it.

One of my fond memories was being followed out of a rural town and entering a low speed "S" curve before hitting a long rural straightaway. The car following me was either a Mustang GT350 or a clone painted like one. I knew what was coming when I went into the "S" curve and I let him cut to the inside as we came out at about 50%. He got to my right rear fender before I hit it. His bumper got to my door before his car went into reverse!!!

 

With published data just for the engine (SBC versus BBC), the differences in weight work out to about 150 lbs (the remainder could be other options, and will include the larger sway bars). If you also consider that the center of gravety for the big block is set back about 16 inches from the front axle and the the overall wheelbase is 96 inches, the basic math will tell you that the front end gains about 100 lbs NET over that of the rear (meaning that each of the wheels share the remaining 50 lbs equally).

This net increase of 100 lbs changes the front/rear weight bias from 47/53 to 51/49 on the small block versus the big block C2. I might note here that the C7 has a weight bias of 50/50, C7 Z51 (the handling version) 51/49, the C7 Z06 51.5/48.5, the 96 LT-1 at 51/49. The 2003 Z06 at 53/47. The C6 ZR1 at 51/49. Most of these cars are at where the big block weight bias is or even more front biased. Point is that there is no magic around the front/rear bias. The key task for the engineers is to make sure that the tires retain full contact with the road as the car undergoes higher lateral g-forces. This is fully accomplished by the tuning effects of the shocks/sway bar modifications.

Of course lateral g-forces are not the only component of a good handling car. Transiant response is another. But by and large, the steering systems are identical and lead to similar feel at turn-in.

So what is different - two things, weight and polar momentum. The power of the big block in an immediate offset to the weight while the increase in the big blocks polar momentum will only make itself be felt (significantly) in higher turn-in speeds where the contact patch of the (front) tire starts to slip. But this will only be felt by racing drivers driving at 10 tenths. And the effects can be overcome by throttle oversteer. So at the limit - you have to be able to drive better when in a big block.

But is the OP likely to EVER drive his car all out in LeMans type conditions to be able to experience what racers would call a front end push at speed? Not likely. I'll stand by my earlier statement that the handling differences between the big blocks and the small blocks in the C2 are effectively nil.

 

Therefore, an all aluminum BB is what is needed...

 

 

I would go with a period correct 327. Next best thing to original engine, and plenty of reliable power.

 

The weight savings on a bbc when you use an aluminum; intake, waterpump, and heads, would offset it's weight penalty.

 

I guess an aluminum small block is the answer.....sigh.....Pretty doubtful the OP is going to put in a big block and drive the car around corners with the throttle, but who knows?

 

Okay peeps, good debate. Always wanted a BB myself. Tell me why I shouldn't drop this remanufactured 427 into my coupe. They say it will fit perfect and everything will hook up. With aluminum heads weight difference is minimal (they say). Turn-key price is under $7k including shipping.

This would work for my driving style (cruising). Only time I mat it is in a straight line anyway. The extra cubes could handle my A/C no problem. Also thinking of upgrading the steering while the motor is out.

What else would I have to address for a 327/350 to 427 swap. Will the bell housing match up? I would replace throw out bearing, but clutch is good. Should I replace it anyway? Springs, shocks, motor mounts, sway bar, wheel bearings, bushings, radiator, exhaust, ball joints?

Just another option I'm exploring if I can get away with just an engine swap and not the whole front end.

TIA
John