Ok, I have a motor all designed to go into my car, but I found this 95 FireHawk for cheap and really want it. Would it be possible to use a 91 block in place of the LT1? I would have the intake fitted for the block, and I don't forsee any other problems than what to do about the distributor. I know LT1's use Optispark, and I hear that it sucks. I was thinking I could use a regular TPI ignition, but how would I get it to work with the computer?

I would just try to translate all the plans to work with an LT1, but LT1 parts are so damned expensive.

Hopefully someone will have ideas or answers, I will prbably post this on Cz28.com if no one has ideas.

 

Why use the L98 block intstead of the LT1? The LT1 has better heads, cam, and computer systems up until 96 when OBDII took over. That must be one bitching motor you got there. If I were you and really wanted the firehawk, I'd sell the motor, get the firehawk and then mod it with the extra cash. Cz28.com will probably have more people with 4th gen experience though. I'd post there now since your really dealing with a 4th gen here.

 

well, the motor is not built yet, but if i built it with a regular style new block from SPDC, it will only cost me around $3400 for an almost complete brand new forged 470hp 383. Using the LT1, it would cost much more than that, to the tune of $8000, for the same amount of power. Money is not really a problem, to a point.

Any ideas?

LT1's are basically the same as regular sbc's, except for the reverse cool, and the optispark, right?

 

You CAN use the block in the firehawk, but you will have to use your existing '89 ECM in place of the LT1's PCM. You will also have to use the '89 auto tranny unless you found a six-speed, because the '95 auto tranny is computer controlled (not just the stall, but the shifts as well). Now you'd have to use a low profile distributor from MSD, or possibly get away with the '87-'92 stock distributor. The cooling won't be too difficult to work around, you can use '89 radiator hoses. The real tricky part is getting the accessories to bolt up properly, LT1's usually have most of their accessories bolted to one side (alternator, water pump, AC) (the passengers side) and it's a serpentine setup to conserve space. You'd have to recreate that on the L98 block, beause of the power steering box on the right side is too close to the block. Another major problem you'd run into is getting L98 headers to fit in the car. You can't use LT1 headers because they have a D-port exhaust port and when you use an LT1 header on an L98 block you'd close off a bit of the exhaust port causing some bad back pressure. You can always run manifolds though! Thirdly the distributor will be under the windshield now and you will have a VERY hard time adjusting timing, changing plugs, and forget about getting to the distributor hold down bolt while actually seeing what you're doing. And just a tip (install the distributor before you put the block in ) So with all this in mind, and you still want to really run an L98 in that cramped little space, do a carb setup and get a cowl hood!!!! Any more questions, feel free to ask

 

Wouldn't I have to swap in the wiring harness, too? Couldn't the headers be modified to fit, if you welded more material on, then machined it to fit? Or just replaced the flanges?

Anybody have any other ideas?

Ohh, yeah the car has a 6spd, so I won't have any tranny woes.

 

The water pump is on the passenger side....no

 

Tomorrow I am going to look at the car again, and I will look at the accessory arrangement. I had kinda thought of that, but dismissed it as a small problem.

 

The water pump is not on the passenger side, it's in the same place all water pumps go.
You'd have to make L98 headers work in the acr, so you'll probably be limited to some L98 shorty headers, cuz if you were planning Long Tubes, forget it. And yes you would have to use your wiring harness from your donor thirdgen to get EFI along with the L98 in that Fourth gen.

 

Coulds you just pot your rotating assembly into an LT1 block?

 

I don't mean to be argumentative, but why couldn't you just cut off the primary flanges and weld on the Standard style ones?

Is there no way to use like a MSD ignition box and ignition controller to control the timing advance and retard and the spark? Of course, disable the stuff in the LT1 PCM.

 

Camaro6spd, that is a good question. Anyone know why LT1 rotating assemblies are so expensive?

 

That reminds me, umm the rotating assemblies of LT1's and L98's are the same, lol. The only thing you'd have to do with the LT1 is get the stock heads ported (just send them to get a GTP stage 2 port job and you have better that AFR head numbers). A LOT of guys on cz28.com are getting 400 RWHP by using a cc306 cam and GTP stage 2 ported heads. And those numbers are on a stock block 350 (well some are 355's). If you're going to buy the Firehawk, just get hooker long tube headers, and do the head/cam job I mentioned and you'll have the same power that your 383 will put out. (Of course there are little free mods, and small mods along the way that add up to the grand total of HP but I'm assuming you'd know what most of 'em are since they're pretty similar to small mods on a thirdgen.)

 

Well, I would just mod out the Firehawk, but it has 104k on it and I know it has been ragged very badly in the past. The cam I have picked out will work in the LT1 also, just gotta check on the heads. I may switch back to my second choice heads if they don't make the ones I want for the LT1.

Thanks for all the help.

 

Well, thanks for all the help guys but the Firehawk was sold when I got there today. Dammit!! Anyway, maybe the deal will go wrong and I will still be able to get it. I doubt it.