whiteminqua

Can I build a combo based on a 260 HP LT 1 from the Caprice? I am not sure about reverse cooling issues and the need to retain ALL of my stock but ported 86 TPI intake, plenum, and emissions equipment. My Pennsylvania mechanic tells me that all must be in place-or no inspection. I know there are guys out there who will inspect it anyway, but I want to keep the car original in appearance. I just want it to run...

So, what can I do here? I have a golden opportunity to buy this engine for cheap, complete with wiring harness.

My thoughts are to mildly port the heads, gasket match, nice roller cam, headers, and what ever else. The motor has 55k miles on it, so I may not have to rebuild it. Will I need a different intake or can I elongate the holes in mine? Can I use the included injectors? What cam? I have a 700r4 that will need attention soon, so I am thinking 2400 stall speed converter. I have 323 gears. What about my distributor and gear/cam issues???? I am lost on this one.

I have not researched this prior. I dont have much time to do this before the motor is gone, so please bear with me. I have spent countless hours here prior looking at GEN 1 350/305 TPI build ups and I am ready to start my project. Then, out of the blue comes this LT 1.

Thanks to all who may venture to help me with this.

92droptopws6

iTrader: (10)

i would say get it if the price is right,be certain it is an LT1 5.7 cause they made an Lt1 4.3 v8 called the babyLt1,if you look on the back of the block by the trans mating surface there is a valley you will see a stamped 5.7 on the block if that isnt there pass on it!
on to the intake deal,you have to modify your factory tpi base a little bit,the center two intake bolts where it mates to the head need to be filled and redrilled(Lt1 style center bolt holes are further apart than your original.
you can also get rid of the opti -spark by using your factory distributor and retain your harness and sell the LT1 harness to get a couple of bucks back.
you will benefit from an aftermarket chip,headers etc.

whiteminqua

The block is marked 5.7. Does anyone know about water pumps and using my original 86 pulley system? Do I need a reverse cooling water pump for this motor? I am wondering if there is a retro fit water pump that matches my accessories for the belt drives.

SheldonZ28

iTrader: (1)

If you want to use your stock TPI setup (which will take a tonne of work to have fit properly) why bother with an LT1 base?

The only advantage over the Gen 1 if you want TPI is the reverse flow cooling. Optispark is **** compared to the earlier HEI.

Only other advantage is the short ram intake, because it flows more, and can revv' higher, and your tossing that one out the window.

Also note that LT1's need special cams, and front accessories

whiteminqua

Ok, I will try to make it simple... Here is what I need to know:

1. Can I bolt my TPI base to the LT1 heads with just minor bolt hole work-OR-is this a lot of work? I want to retain my TPI because I like the way it looks and for Pennsylania emissions laws. (I already have 2 different opinions in this post already and I honestly DONT KNOW the answer)

2. I will be getting a hotter cam. I will not use the stock one. This will include my stock but upgraded TPI ignition system and replace the OPTI CRAP. (what about the cam gear and distributor gear?)

3. Do I need a special water pump for this application? I know the LT1 is reverse flow. My stock 86 IROC 305 is NOT. Can I buy a reverse flow water pump to fit this motor and work with my application?

4. What about my accessories: Power steering, air, air pump, etc.... will they bolt up to the LT 1 heads?

Drac0nic

On the emissions regulations I would definitely want to check with someone else on that. In a lot of states, you are allowed to legally swap an engine so long as it is newer and maintains the same smog equipment as the original (EGR, AIR catalytic converter etc.) I'm not saying that your does but it does vary from state to state. Since it's a SEFI motor I would think that a B-body LT1 would be considerably cleaner from the tail pipe than a batch fire setup stock for stock, not to mention it uses a higher tech ECU.

whiteminqua

According to my inspection mechanic, it doesnt matter. It just needs the same emissions equipment in place. Its a visual inspection only.

A lot of Camaro and Mustang owners who removed the emission controls years ago are now scrounging to find the parts so they can get their cars inspected. The shop has a book with a checklist of items that should be on each car. My mechanic told me that I can use any smallblock because they dont check the data.

chevyowner02

iTrader: (3)

IIRC the LT1 wp is the only one that you can use. If it was me why not keep it all LT1?Seems like the intake is a little better than the tpi? I have seen some guys switching the tpi out for the LT1 intake.And on cam get the cc503 nice dd cam my

whiteminqua

I know the LT 1 is a better intake. More hp and more rpm. I dont want to use the intake. I LIKE my TPI, it looks cool. It passes my Pa. state inspection for emissions. If I change it, my car cannot legally be inspected. I cannot use it.

That is why I want to use the TPI system and not use the LT1 intake.

Once again, here are my questions.....

1. Can I bolt my TPI base to the LT1 heads with just minor bolt hole work-OR-is this a lot of work? I want to retain my TPI because I like the way it looks and for Pennsylania emissions laws. (I already have 2 different opinions in this post already and I honestly DONT KNOW the answer)

2. I will be getting a hotter cam. I will not use the stock one. This will include my stock but upgraded TPI ignition system and replace the OPTI CRAP. (what about the cam gear and distributor gear?)

3. Do I need a special water pump for this application? I know the LT1 is reverse flow. My stock 86 IROC 305 is NOT. Can I buy a reverse flow water pump to fit this motor and work with my application?

4. What about my accessories: Power steering, air, air pump, etc.... will they bolt up to the LT 1 heads?

Im not trying to be rude or a wise guy, so please dont beat me up over this. I am trying to make an informed decision about this engine.

socal

what your asking can be done but is worthless
Otherwise its the same bottom end w revers cooling and yes you have to run and lt pump w an lt
Just do the full lt swap keep all the lt accessories and have spearthech or whoever wire it so it all works and psses smog. I just suggestesd speartech since he did ours and it was so nice to just bolt it in vs try to figuer it all out. This is from experience

1 no its not just elongating the bolt holes lt port are taller and welding will be requiered

2 the cam doesnt matter unless you use the opti, the chain gear set is what drivers the water pump so the only other option then stock is to get a foctory rollercam replacement chain and gear set lets say for a 92 v8 camaro and plug the drive hole for the h2o this requiers runnig an electric pump

3 #2 kind of anwered this the lt pump is for the lt and has to be used unless its all custom and for a street car thats pointless. i have seen a kit to put a machanical fan on an lt but it was expensive and i dont think you can put a pulley on with that kit so no you cant buy one to mak it work

4 yes they will bolt up but the lt stuff is cleaner and nicer so why unless it for the a/c, but you live in PA. And the factory stuff may not clear the opti and h2o pump that have no choice but to be there. You are running a multi belt acessoriy system i guess the good option would be to convert to serpentine system from lets say a 92 v8 camaro or any thing else that came with that set up many vehicals ran it and i think you may be able to bypass the h20 pump w a shorter belt

I know your not being rude and hope this awnsers your questions but i just put together what everone was saying. And check with you inspection officer, (not the guy who give the sticker) on the ruels. As i know them so long as its newer and has the equipment its good

whiteminqua

It may be worthless to you, but I have the chance here to buy a 55k mile LT 1 for $500.00. And, it comes with the original wiring harness. This block is roller cam. My 305 is flat tappet cammed. This has LT 1 heads. My 305 does not. I can build a nice street motor with this combo IF, I said IF-I can match up my accessories to the waterpump and heads. This is the most serious issue that I have found so far.

One more thing, I cant spend the money for all of the conversion parts that the LT1 Camaros would have used. The air conditioning compress, alternator, power steering, etc. are all different than on my car.
My car must remain STOCK APPEARING TO PASS SMOG LAWS OR I CANNOT GET IT LICENSED. Its pass or fail, thats it.

whiteminqua

I just re-read all of this. It sounds to me like I should forget this motor and build a gen 1 motor instead. Thanks for the info guys, I do appreciate this.

I was hoping to have an upgraded base with roller cam and good heads, but this looks like too much trouble.

SheldonZ28

iTrader: (1)

Good idea.

To answer all your questions further:

1. Possibly, NOT worth it. Coolant passages need to be plugged, holes moved etc.

2. Cam doesnt matter, as said. But once you replace the opti and LT1 intake, you now have a reverse cooled Gen 1. Not worth it, almost all the LT1 advantages are now gone.

3. LT pump MUST be used due to reverse flow cooling

4. your stock accessories will NOT bolt up due to the water pump.

Also, to swap an LT1 in, with ac, you need to hammer a bit on the k-member, modify a fuel line, and have a custom harness made, or make one yourself. use a '93 camaro TB and you can use it with a stock tranny.

socal

a complet $500 lt1 is no big deal i got one for 300 and just used the block to build my 396. Sounds to me like you don't really understand the differances between an lt an gen 1 enough. You need to read the thread about converting lt1 heads to gen 1, and that lt1 are the same as vortecs that are made for gen1 if thats all your looking at. Ether way good luck

whiteminqua

Well, didnt my questions make it obvious? I cant ask them any clearer. I have no interest in using LT 1 heads on a gen 1 block.

I have read as many of the posts as possible, and there is a lot of conflicting information, just like in this thread.

I know that there are some basic differences in the blocks between gen 1 and gen 2. The biggest problem in using the gen 2 block with gen 1 is the water pump. It seems that the water pump from a gen 1 will not bolt up to the block of a gen 2. So, at that point, I cannot use the LT 1. Party over.

Im going to build my gen 1 block instead. I have an old 4 bolt main 350 that is waiting for a tear down and a trip to the machine shop.

socal

[quote=whiteminqua;3432041]Well, didnt my questions make it obvious? I cant ask them any clearer. I have no interest in using LT 1 heads on a gen 1 block.

I see that and didn't say you were, but you might not be getting the lt1 head is the same as a vortech just that the vortech is casted to work with the gen 1. So if you want the power of an lt1 and keep your tpi get the vorthech heads and a vortech baseplate. You just won't benifit any of the revers cooling properties. And the thread is clear you just aren't understanding its not just the water pump.