i have a 90 zr1 and im wondering if they sell a kit to put in a 454, is it all custom fab work, or can it be done, any help would be great tahnsk Dan

 

If you're talking about putting in an actual big block, it's certainly not a new idea, and it has been done before. GM did it on a '90 convertible (called ZR2 'Big Doggie'), and I think at least one person on this forum (if not more) has also done the swap.

It's a big job, to say the least. I do not believe there are any kits available for this conversion, so virtually all the work involves custom fabrication. And I also don't think that you can use the ZF6 speed transmission either - you'd probably have to use a Tubro Hydramatic 400. In fact, the reason GM built the ZR2 was to study whether or not it was viable to offer a big block C4 as either a potential RPO option, or to make available the necessary components as over-the-counter dealer parts for customers looking to perform the conversion themselves. Needless to say, they axed the entire idea because of the extensive work involved.

Now, if you are talking about replacing the pistons and cylinder liners on your LT5 motor in an effort to increase the displacement to something around 454cid, that's a different story. I believe that Lingenfelter (and maybe DRM too) offers a kit that may do what you're looking for, but I don't believe it's a full 454cid. I would suggest that you ask this question on the ZR1 discussion section of the forum - I'm sure those guys would be able to point you in the right direction.

Hope that provides some answers.

 

It is actually a 414 inch engine. And it is very very expensive, for the crank and the liners. Pistons are no more expensive to make than any other piston. But the liners and the crank are the expensive peices.

 

IIRC, he sold the stock motor & trans, so it's no longer much different than any other C4.
Not too hard to do a carb'd BBC...but good luck smogging it.

 

I don't see why the ZF wouldn't work on a BB. Call McCleod or Centerforce:I guarantee they have what you need. The bellhousing should bolt right up! Keep us posted on your progress

Make sure and let them know how many teeth (153 or168) are on your flywheel and if your motor has a one or two piece rear main seal.

 

I was gonna say! I thought he wanted to chop up a Z...

Now, that cleared up. I would get a Motown 454. You still get your 454 but you get it in small block form. Less weight, same power. Its win win and less fabbing work for you!

 

But those large valve covers are just so damn sexy! :drool:

 

I didn't realize that the crank was replaced too!

You're right, that would be expensive.

I was wrong, it can. I just looked it up in one of the Road & Track Corvette Special Series magazines I have, and it says that while the original ZR2 used an automatic transmission, they later switched it to a ZF6. My mistake. :o

 

You bet there is a way to get one of those big blocks in there. This can be a real easy thing to do or it can be VERY involved. For example... if you want to go the carburator route and also ditch your A/C while you're at it, then your life will be MUCh easier. On the other hand, if you want to keep your fuel injection and A/C then it gets more involved. Here's a few tips.

1. The stock motor mounts work just fine.

2. Of course the motor will bolt up with no problems to the ZF6 bell housing. I used a specially made McLeod street twin clutch.

3. Make sure you use a 9.8" deck block, I used a 10.2 block and believe it or not, but just pushing things out .4" makes all of the difference in the world as far as your valve covers hitting the A/C box and windshield wiper motor.

4. Use a blower box and evaporator box/cover from a ZR1. If you use a standard deck block and regular short valve covers (no roller rockers) then you should have no problems with the valve covers hitting anything, even your windshield wiper motor. I used the Mickey Thompson valve covers which are medium height. The driver's side rear cover hit the wiper motor so I notched it. Not a big deal because if you look at the valve arrangement you have tons of room to make a notch in the back to clear. If you choose to use roller rockers or shaft rockers (I chose the Jesels), then you'll have to make further mods. to the evap. cover. Not a big deal, just cutting, refiberglassing, and painting.

5. I used Sanderson shorty headers that have 1 7/8 primaries and 3" collectors. I've heard rumors that some of the standard headers do fit... but I would have some concerns about clearance with the ground. I'm guessing custom larger headers we be on my "to do" list someday.

6. Once again, if you go the carb. route then you can stab in any old distributor.. if F/I is being used, you can simply re-use your old dist. By using a raised deck block, I had to lathe down the collar on my MSD and make a slip collar to allow it to slip down into the block further. Nobody makes a tall deck computer controlled distributor that will keep your stock ECU thinking that it’s controlling everything. Update, actually I switched over to a magnetic triggered dist. Which means that the stock ECU no longer receives the reference pulses from the HEI, and believe it or not my gauges and speedo still function fine being controlled by the stock ECU. I use the FAST ECU to actually control the fuel air and spark functions of the engine. I had Mak at Fast Track Performance make a cut-in harness to my stock ECU.

7. You will have to move the steering rack forward by about 1.5 - 2". This really isn't that big of a deal. Your tie rod ends should still have plenty of room for adjustment to straighten the tires back out for alignment purposes. I moved mine maybe 2-2.25" forward simply because I added the blower drive pulley in front of the regular accessory drive pulley. Of course you'll also have to lengthen your steering column as well. I also had to notch the front support bar that runs in front of the motor to clear the supercharger drive.

8. If you install a suoerchartger like I did you may also find that you'll have to move your front sway bar mounts forward about 2 inches. You must be careful because if you move them too far forward your rims will hit the sway bar when you crank the wheels real hard. I actually found a place here in Indy that was able to bend (not an easy task) the ends of my solid front sway bar in toward the frame in order to help with the clearance issue. Don't ask me how I know this.. I think it might be necessary to use heim joint end links to accomplish this. That's what I used anyway..

9. You'll also have to make a valley in the K-member about a half inch deep in order to clear the oil pan. By the way, use a regular oil pan as the fancy drag race pans with kick outs don't work. Trust me, your headers will hit them.

10. Intake manifold. I had one custom made (before I learned to tig weld). Since then I've made many modifications to it.. I think at last check I have over $2,500 in it (wasted money). An easier route would be to just put a hole in the hood, or perhaps a really low rise intake would work with a carb under a raised cowl hood. I guarantee you that you'll never get a carb under a stock hood.. I'm not even sure you can get it under a 2" cowl hood.. it's that close..!! If I had it to do over... I would use a Holley EFI manifold, make a simple tube that has a hat which covers/bolts to the carb hole, and then run it forward where I would mount my throttle body and linkage similar to a stock C4... much easier and cheaper..

11. I'm not sure if a stock radiator can cool a BB. I went with a custom BeCool, did away with the factory shroud, stood everything straight up. In the heat of summer my car runs in the 180s.

12. Accessories. Well, you are pretty much on your own with this one.. It may end up making you cry. I've seen people use the factory stuff so it is possible. Instead, I ordered Zoops brackets and modified them. I couldn't use the stock drive brackets because of my supercharger. Adding the supercharger complicated everything ten fold, and it really is a engineering marvel (if I do say so myself). I remember when I was trying to determine if it would fit, I would have my wife close the hood with me inside the engine compartment (no engine of course) with the supercharger in hand. I would mock it up where I wanted it to be positioned. And yes, depending on her mood she wouldn't always let me out right away. Let me tell you, I spent more than one night just staring at it all wondering if/how it would fit.

This is the first project of this type that I have attempted. It came out OK, but not perfect. I used basic hand tools (OK, I do have a Harborfreight lathe, drill press, hydraulic press, and a polishing wheel) and a lot of time... 26 months working mostly after the kids were in bed. I guess the best part is that I did it all by myself...every single bit..except for the screwed up warped intake that I had made.. After that horrible experence... I learned to weld for myself!

If you want to see more pictures there is a link somewhere in the C4 forced induction section under Procharged Big BLock (reborn).

Later,

Tony

 

Tony, how do such projects “slide under the radar”? (Radar = wife).

I have to fly in “stealth” mode just to keep my baby maintained. Modifications attract all kinds of attention. Not that I don’t eventually get what I need but man… a blown big block? I’d end up smoking a turd in hell for that one.

 

You sure you want to do that to a ZR1? I mean, not that I'm a purist or anything like that, but wouldn't you rather swap a big-block into an L98 car? The ZR1's are pretty valuable already, not to mention it's a 1990 (first year, right?). Unless, of course, value is of no consequence to you, and you just want to drive a wicked Vette...

Just asking...

 

Why not sell the Z to someone who wants it and mod a standard L98?

 

My car was a L98 car.. I would have never done that to a Z. I only worked on it at night after the kids were in bed. That's why it took over two years to complete..

 

 

You guys are getting stuck on what I first got stuck on too. Look at Timspeed's post. The Z has already been gutted mechanically. Right now its a C4 with a wide butt. Unless he can get matching number ZR1 parts back in it, I think the value of it is already shot.
(No offense intended)

 

It would be cool to do a BBC to a gutted Z.. although the trans. would not fit your standard Chevy V8 as the input shaft is the wrong length.. The motor mounts might be different, and your insurance would be more than a L98. Would be cool though..

 

There's enough Z's in a bubble to go around. If it's already lost its motor, why not? On the other hand, for what a stout big block would cost to build, you could find a good used LT5 to drop in there.

 

Got it. I guess it pays to read more thoroughly!

Don't worry, no offense taken. All is

I remember this one company called Street & Performance used to sell a kit to bolt in the big-block in a C4. There used to be a whole page dedicated to it with pictures and everything. I didn't see it this time, but you might give them a call to see if they still sell the kit. Their web address is http://www.hotrodlane.cc/

Give them a try.

 

keep in mind that the ZF6 for the ZR1 has a different input shaft length (longer) than the Lt1/4/L98 ZF6 variants.

I'd just go with a motown 454 SMALL Block...add AFR 195 heads (or their 210 rasied runner) with a Miniram (or custom intake). The smaller package will rev much quicker yet have the same hp/TQ characteristics of the big block. You'll have to look at the flow of the heads to make your decision.

LOL