techlc

I'm looking for information on a c4 bigblock engine swap.

0ski_dwn_it

a few have done it, but its a HUGE project and extends well beyond the engine bay, ie rear end complete change-over to solid axle etc.

In the long run you would be MUCH better to put a good small block together with great parts that will run EVERY bit as quick as a big block.

We run nearly every weekend and run every bit with most big blocks....now granted you could put a 20+ thousand dollar 555CI motor or 632CI motor and run quicker, but you better figure on a 40+ thousand dollar bill to harness the power and do it right.

My suggestion would be to put together a good SBC, that will fit in with no mods and you can still keep the car a vette. Unless your trying to go 8s, a BB is really a PITA project. And even then a good sbc with a good healthy shot of juice might near 8s on a good weather day with LOTS of traction.

TerryMathews

Got to agree here, if you're wanting to do a BBC, you're looking at the wrong car.

GeosFun

You should go to "It's together (and boy is she sexy!)", currently on page 8 of this forum. Lots of information for you.

NitrousSam

I had considered a big block in my C4 once but it is a giant pain. Jimmy Jackson had done one and raced it in the original NMCA super street class with a fuel injected Lingenfelter fuel injected engine. I have some photos of the setup if you would like for me to e-mail you. Keep in mind this is a major undertaking and you have lots of space issues, major custom headers and if you make a ton of torque you may have to replace your entire drivetrain if you are going to hot rod it. Now if you are just going to gut your engine bay and have something that looks different but not really race it or thrash it you might be able to get away with it with the factory drive train.

BigC4

I put a big block in an 86 I had to notch the frame and weld in a section, but it wasn't that bad. You will need to use a single v-groove belt because the balancer is real close to the rack and pinion. Or you could move the rack forward. I took it out, because I am going to put it in the 94 with some turbos. When I do this next time I am going to shift the motor backwards, because there seemed to be plenty of room behind the distributor.

NitrousSam

Do you have photos of your big block and the conversion?

BigC4

I should, but I will have to look for them. I usually take pictures of everything.

Fubar569

that's my thread! i finally got referenced on the forum...my life is now complete!!!

seriously though, like everyone's said, it's a project. unless you already have the resources and money and alot of time, don't do it. i had the engine here, and plenty of funds in the bank. i plan on notching the crossmember and pushing the rack forward about 1/2" so the march serpentine system will clear with no issues. you will also have to modify the HVAC box or replace with an orig. ZR1 unit to clear the valve cover. the mounts are the same and everything else is a drop in. Sanderson block hugger headers will clear (verified by TONYDEE) so that's one less worry on the exhaust though i'm hoping hedmans will clear since they are the only block hugger i've found with 2" primaries and a 3" collector together...also, you will need a cowl of some sort. mine is working out right now to be needing almost a 4" cowl to tuck it all under the hood. if you went straight carb you wouldn't have 1/2 the worries i am with this but i'm gonna try to crossfire this thing. if all else fails i got a good line on a demon and it won't break my heart to switch...

if you're looking for easy power, a built SBC is the way to go. If you have the time, money, effort, and resources to DO IT RIGHT (read NO HALFASSING) and would like a unique touch, then by all means go for it.

techlc

Thx for the info, I wish I had more time to contribute to the forum. I'm going for the stock semi warmed over 427, 10:1, mild cam, probably TBI, and headers. I was looking for more power, and some looks. Just the info on the clearance for the rack, hvac and header choices have confirmed what we have found.

techlc

I would be very appreciative for any photos as well, thx.....

loiq

look up TONYDEE64 - he's got a big block in his car.

0ski_dwn_it

And dont forget about throwing the weight bias of the car completely off, from nearly perfect front/back to way heavier in the front.

You will need a set of custom made headers as well. Which will be about 1200-1500 dollars - uncoated.

The AC blower and stuff on the firewall will also need to be removed to gain side clearance.

The easiest, if you want to call it easy, way I saw it done was putting in a frontal motor plate, welded to the front suspension brackets. This makes it easier, since you don't have to worry about motor mounts and it gets the motor moved further forward to gain some more clearance.

Also on these cars you have to add knuckles to the steering to work around the headers and motor since it is wider.

GlennS87

This would seem the cheaper solution in the long run. http://www.shafiroff.com/472_675_engine.asp

If I was starting all over I would probably do this with some sort of custom efi manifold and DFI.

Fubar569

in the article i was sent on this swap it mentions a spacer, but no addition of knuckles. perhaps if anything modified ZR1 parts would offer the needed clearance since well...it's wider too...lol

Ramrod92

Actually, the ZR1 is them same at the front. It starts to widen at the doors. Here's Phil Tobin's 555 in his 93. And if you do go that route, you'll need more time and $$$ for stuff like this And when that's not enough, you start adding nasty stuff like this It's an addiction....