I have a 86 trans am with a 350 TPI with some mods.
I have the option to put a stock LT1 in the car.
Would this be of any real benifit?
I know the power level would be lower on the LT1 until I started to modify it.
What advantages do the Lt1 have over the TPI and vise versa.
Thanks

 

The LT1 makes more power than the L98. The L98 makes really good low end toruq and it comes in pretty fast in the curve but the LT1 also makes great torque and it stays flatter than the TPI. The LT1 makes about 300hp bone stock and with the same torque as the L98. I would take the LT1 and mod it before I dropped it in. Your L98 is to close in performacxe to change it now. Spend some time on the new motor and prepare yourself for a intensive swap. It will feel much better if you drop in a 450hp LT1 after all your work than a 300hp one.

EDIT: I forgot to add that I met a guy at the local f-body meet here in dayton that has a 89 IROC T5 with a bone stock LT1 swap. The car also has 3.42 gears and cowl hood but ran a 13.01. Thats not bad at all. Imagine what it would do with a cam and some head work.

 

A cam & exhaust TPI car is at best about equal to a stock LT1, given a properly selected cam.

A cam & exhaust LT1 is out of the range of any modded TPI, except for power adders. That's TPI: not SuperRam, StealthRam, MiniRam, etc. Those replacements for TPI have similar potential to the LT1.

It's cheaper and easier to get big power out of the LT1 compared to TPI, because the heads are better to begin with; it has higher compression; better control system; and above all, no restrictive tuned long runners (about 10" total compared to 22")

 

By modified TPI
I have a 1 piece rear main 350 block bored to a 355
edelbrock heads and lower base
9.6:1 comp with keith black pistons
58mm throttle body
I will be porting the plenum and adding some sort of better runners. (or switching intakes alltogther)
The motor was built about 4 yrs ago with very few (like <200 miles) on it.

Could a cam and some other very small mods to a LT1 make a similar power to this TPI motor?

Also the LT1 has abour 90000 miles on it. (have no idea how it was driven)

thanks for your replies

 

Not only will it make the same torque, that power will not fall flat as the rpm's go up. No matter how much you port that plenum and runners you are not going have the high rpm advatange of the LT1. A simple cam swap and a little head porting can easiler deliever an LT1 past the 400hp mark.

 

I guess if you put a smaller than stock cam in the LT1, maybe a more restrictive exhaust too, you could get it to make the same or at least similar power as a TPI motor.... shouldn't be too hard....

I could be wrong, but I do believe you can buy a whole junk LT1 for less money than all that add-on stuff for TPI would cost, and make more power than the modded TPI without doing anything at all to the LT1; and still have lots more room to mod it, instead of having a totally maxed-out TPI with no further potential for when you still get beat by newer cars.

 

I have seen them go complete with wiring, computer, and accessories for a cool 1000. Not bad if you ask me.

 

I have an 1986 camaro iroc-z with the 350tpi, is it possible to put the LT1 in it? and is it worth it?

 

I have never been happy with lt1 cars my self. I guess if you figure cost wise (not figuring the time involved) the lt1 is a good deal.

but you can mini ram a l98.
your head choice won't be as limited.
you won't need to worry about the opti spark going bad and the pricey water pump. this is the way to go IMOP but the cost of the intake, fuel rails, other odds and ends will cost more befor you even touch the heads.

 

I second staying with the engine you have, you won't enjoy replacing the LT1's high dollar 1 off parts. Just purchase a Stealth Ram, or similar intake for your L98 you have now.

 

I'm pretty much on the "modded TPI" page as well. Although, I have been bashed by saying that because some people think you aren't dealing with TPI anymore when you dump the intake.

If you dump the TPI intake and run any other LT1-style intake, I don't think the LT1 has an advantage anymore. With a ram-style intake, you can run good cheap modded heads to flow as good, so with all other things similar, I don't think the Opti-spark is worth the extra headache...

Just my opinion...

 

yah...see someone was just going to up and give me the lt1....i know that the lt1 is pretty similar tho but the engine chokes it self hmm i wanted to stay with the l98 tho. explain what u mean by changing to a ram-style intake, and the cheep modded heads??? is that with the l98 or what? and if u could what headaces come with the (lt1) opti-spark?
----------
AWWW I C change the intake so it dont choke it self as bad or at all???

 

The headache with the opti-spark is the money it costs to replace it! I spend less on entire cars than what that system costs to tune.

I'd stay with the L98 and buy this:

https://www.thirdgen.org/forums/engi...t1-intake.html

Take that intake to the machine shop, along with a junkyard small block chevy intake that has a distributor hole in it, like an old carb intake. Have them cut the distributor hole perfectly in the exact place as the carb intake, that's step one. This intake alone will improve your L98 to world class f.i. standards; that's why GM ditched the TPI in favor of the LT1! You will also need to match the coolant and intake ports with a set of intake gaskets that fit your head.

Next, run an LT1 or LT4 hot cam.

I'm confused that you have an 86 car with a 350 TPI in it? What year is the engine? If it's 86 or older, I think you'll need retro-fit roller lifters to run the above cam.

Heads... what heads do you have? If you have TPI heads you just need big valves (1.94" or 2.02") and some port work to keep up with an LT1. You were gonna rebuild the heads anyway, right? Don't forget the high lift valve springs!

This recipe is easily an LT1 equivalent with a little tuning. Because I am a budget guy, it would take me a long time because I want mostly used parts to keep the budget down. I do my own work, except the machining, and I just can't justify the cost of a complete LT1.

 

the engine is out of an 88 camaro iroc-z

 

From Ruiny
"By modified TPI
I have a 1 piece rear main 350 block bored to a 355
edelbrock heads and lower base
9.6:1 comp with keith black pistons
58mm throttle body
I will be porting the plenum and adding some sort of better runners. (or switching intakes alltogther)
The motor was built about 4 yrs ago with very few (like <200 miles) on it.

Could a cam and some other very small mods to a LT1 make a similar power to this TPI motor?

Also the LT1 has abour 90000 miles on it. (have no idea how it was driven)

thanks for your replies"

In no way will the LT1 be worth it. You need a cam, I'm assuming you have roller lifters already? You also need to do something with those runners and get the plenum ported.

 

i only have stock heads? i wanted to put the vortec heads from the lt1 but i guess it wouldn't work. how would i go about getting bigger valves? for intake and exhaust? and what about the high lift valve springs?

 

Your current heads will be fine; you need to find a good machine shop to do the rest.

Have them check the heads first for cracks and warpage and such. Once they are okay, you can have them machine your heads for high lift dual valve springs. After that you can talk to them about intake valve size and exhaust valve size when you are getting your valve job done. You will want either 1.94" or 2.02" intake valves and 1.60 exhaust valves. I like the 1.94" valves but others like the bigger ones. For a 350, you'll be fine either way.

If you want to port match your heads or do any port grinding or polishing, I'd recommend that you do that after your machine shop checks the heads for problems. Do your grinding and then take them back to the shop to have them machined and finished.

You'll be happy you did this.

 

I'm going to say go with the LT1, people say that the opti is crap, it isn't, the waterpump is crap, it isn't (plus CSI makes an electric one that goes in the original housing), these motors can take the punishment that the older ones can't. Powder metal rods, hyperutetic pistons, beefier crank than the L98s, more compression (10.5:1) and a breeze to tune (costs about as much to have it dyno tuned as getting a chip burned when dyno tuning and you don't have to find someone to do it) and they can turn the RPM's. I know of people that ran LT1's spinning them to 7300 on the stock bottom end for over 2 years and never had a problem, mine sees 6300 quite often and no problems here. Lloyd Elliot has probably the best head/cam kits available for the LT1s (the stock LT1 castings can flow quite a bit when put in the hands of a skilled porter).

 

Optispark "problems" are usually just people whining about how their 120,000 mile cap and rotor failed, other lack of maintenance, etc. They arent in the best location, no, but if you take care of your car its going to last. Expensive ? Price a decent distributor for a tpi car, and the $375 for a new OEM delco optispark really isnt that bad. Add to that the fact that for just over $400 you can add a 4 coil ignition setup removing the high side voltage from the opti and possibly making it last who knows how long.

Expensive water pump you say ? Its $195 for a new OEM delco pump from gmpartsdirect. Since its aluminum its only fair to compare it to a 91 corvette pump for the serpentine setup, $198. Not much of a difference there.

Sure you can modify the intake to fit, then change the heads to something that flow decent, and on an on with the hacking. Seriously compared to just bolting in the LT1, you are wasting a lot of time and headache, not to mention all of the hours you are going to have to spend tuning it, etc, and then you are still dealing with an 80's gm efi setup because you've retained the stock computer.

Add to that the LT1 is lighter, more compact (accessories are small and on the passenger side), easier to work on when compared to the TPI style intakes, comparing it to an LT1 modified intake gen 1 your still going through more work to do most repairs, the LT1 has no coolant passages in the intake manifold making an intake gasket swap a quick and easy deal since you wont get any water in your oil, same goes for a cam swap.

An LT1/auto setup can easily be had for around $1200 if not less if you try. For which you gain:

Aluminum heads - weight loss and flow more than your TPI's heads, you'd spend a good bit having them ported for them to flow similar.

Compact lightweight intake- compare its weight to a TPI intake setup, its a serious weight drop between the two, let alone being a LOT easier to work on.

Compact lightweight front driven accessories- One bracket instead of two, weight loss there and the aluminum water pump. Add to this one the 124A minimum or possible 140A stock aternators.

Better drivability when comparing a 700R4/TPI to a 4L60E/LT1, it just makes the car that much nicer to drive.
----------
Oh and the ability to run the electric water pump as Klortho mentioned without any extra troubles, they're cheap, dont require an accessory drive change and free up about 8 RWHP iirc.

 

The LT1(94-95) is way easier on the programming side. Plug in a laptop to the LT1 engine harness, no burning chips. No changing speedometer gears either when you change tire sizes or gears, just reprogram. Then the 4L60E I like a lot better than the 700R4 mostly because TV cables suck.

Other things- I've been able to relocate the alternator down low, no accessories up top, very clean look and easy to take off the valve covers.

 

The LT1 doesn't have Vortec heads. They only came on trucks. You can get them from the junk yard from such a truck, or buy them new (many sources).

You don't need bigger valves, especially with TPI. Valve springs - Summit, Jegs, Comp Cams, Crane, etc.

 

This thread has gotten stupid, he already has Edelbrock heads and an Edelbrock base why in the .HELL. would he want to change out what he has for something almost equivilant! How many of you have actually owned and worked on LT1 cars? Also keep in mind the damn things change about every single year they were produced! I will repeat this one more time IT IS NOT WORTH IT IN THIS CASE PERIOD! He already has a low milleage engine that's a great foundation for a fast car, there's no point to switching it over to an engine that's going to be the same only with WAY more miles. Here's a plan, take the LT1, sell it, and buy yourself a mini ram and cam for your L98; save you A L O T of headache in the end.

 

Make up your mind, if his edelbrock heads and base are so great why would you suggest he switch to a mini ram ? Also keep in mind the new price of a miniram and its fuel rail are more than an LT1 can reasonably be had for.

Oh heres some head flow numbers comparing an LT1 head to the edelbrock 60859 which he probably has. Doubt he's got performer rpms, the top is the edelbrock, the bottom a stock LT1, wow what a surprise the edelbrock head doesnt flow more until .600 lift, everywhere else the stock pos LT1 head outflows it.

.200 .300 .400 .500 .600
64/54 122/96 177/124 217/147 229/166


75/52 129/100 180/130 213/142 214/149

Heres my little list we'll start with owned then with the worked on.

1986 Z28 LT1/T56
1988 Camaro LT1/T56
1994 Z28 Teal LT1/T56
1994 Z28 Maroon LT1/T56

Guess i've owned a few.

1992 RS Red 3.1 Ttop- LT1/4L60E swap, edelbrock headers, 3.23 posi disc, flowmaster catback, a/c

1992 RS Purple 305TBI / 700R4 - LT1 / 700R4 swap, replaced with 4L60E after 700 died. 3.27 9 bolt, stock HO exhaust manifolds and 2.5" pipe to flowmaster muffler

1991 RS 3.1 Black -LT1/ Built 4L60E, 3.23 posi disc 10 bolt, edelbrock headers, jegs catback,

1988 Sport coupe, 92' dash and chassis harness swap, 94 LT1/T56, a/c delete, slp headers, magnaflow catback with 4th gen catalytic converter, 3.42 posi disc 10 bolt, 4th gen fuel tank.

92-93 was the same, 94-97 are the same, wow an updated opti with a vent, and a crank sensor in 96-97, the engine is the same. TPI's had just as many if not more changes throughout the years.

Way more miles ? are you kidding me ? i've disassembled quite a few LT1's, each still had the crosshatch on the cylinder walls, the highest was in the high 200k mile range.

Heres a real plan, sell the stuff you have, put a cam in the LT1 and have more power with better drivability, and enjoy the easier to work on engine.

 

Equivilant? even with the heads and base, I doubt very much that it is equivilant to a stock LT1. If he gained 50hp with that, then maybe.


Umm...guess you didn't see my sig, currently running a '95 LT1 with 150k on the opti and original water pump. Like Z28 said, it comes to maint on these. Yes, the cap/rotor is 120 bucks and not that hard to change.
Quesion is, how many LT1 cars have you ever owned and worked on?

The motor itself didn't change every year, get your facts straight before saying something like this. Again, redesigned opti in '95 (changing the way it's driven vs the splined method) and '96 going to OBDII and adding a crank sensor and 2 more O2s, sounds like they changed a whole bunch.

L98s can be made fast, sure....if you want to spend a ton of money on it

LT1s are a better foundation to make an even faster car with about the same amount or maybe a little less.

But this is getting pointless to argue the point and the thread needs to get back on topic.

 

I think a great deal of confusion is present here, mostly due to the fact that the original poster has fled the scene. Ruiny? Hello?

Anyway, the guy I was responding to was 06andersen and my advice stands. I am giving advice on what I have experience with. I have messed with LT1s but I wouldn't buy one on purpose. That's my opinion.

I work on my stuff myself, so porting heads doesn't cost any more money than what my time is worth and some dremel bits. I have more time than money always so it's worth it to me to buy used stuff that is "inferior" and to make it comparable to more expensive ready to run parts.

I don't agree at all with the notion of the "80s computer management inferiority," compared to the OBD2 stuff. If you like OBD2, fine, run it, but you can plug laptops into the older stuff as well after you've taken the time to set yorself up with tunerpro or moates, or whatever you use.

These forums are often asking for advice based on experience. That's why when someone asks about camparisons between LT1 and TPI I give what I have. My experience with optispark is that it's damn expensive for a tune-up. I don't know about you, but I don't replace the entire distributor for 190 bucks when I do a tune up. Even if I have to buy a bushing to rehab the distributor, I'm not paying a 190 dollars. I'm buying a junkyard distributor, rebuilding that one at my house, and then putting on my car... budget is my key word.

Ditto the water pump issue. I don't care about aluminum water pumps unless I get them cheap.

I also don't like the crossmember mods that must be done to put the LT1 in the car and retain the accessories. A hack job is not porting your TPI heads in order to make them flow as well as an LT1; a hack job is throwing out your A/C system because you didn't cut/flip/box/weld your engine cradle for your wonderfully superior LT1 brackets to fit.

 

thank you for the help i already knew i was in for a real headach when swaping cuz id have to change the computer the wireing and a bunch of shot. i still have the 305 tpi in my car im buying a long block 350tpi from an 89 camaro from autozone. that what i was trying to get figured out cuz i was just going to buy a LT1 and Transmission. i just want that when i get my L98 or what ever i want it to be better than the lt1. i love this body style and i dont want to get ride of it but i was told to go to the newer style. i think out of everthing i can make this body style better and faster than an LT1 correct?

 

I don't know that I would have auto zoned the engine, but....

"Speed is just a question of money; how fast can you afford to go?"

 

I was under the impression that 06anderson WAS Ruiny. I actually read through twice and the flow of the posts was transitional; I just figured he lost his password or something and came in under a different name It's never a good plan to swap an LT1 into a third gen, stay with the TPI engine, or go straight to the LS1 style setup. You can get what you want from an L98 setup; besides this is a Thirdgen forum we should all be a little more loyal to our older much sleeker looking technology *a bit biased yes*.

 

Why is it never a good plan to swap an LT1? You have to make the same modifications (more actually) to run an LS1 in a third gen, you are making no sense with this comment.

 

80's computer management is inferior, mine isn't OBDII, it's still OBDI and all I have to do is plug my laptop into the data port, make the changes flash it and it's done, no having to buy chip burners and chips to make changes, no need to pull the chip put it in the burner, plug it back in taking a chance on screwing the socket up. Plus if I want to get a dyno tune, I don't have to search forever for someone who has the equipment to burn the prom.

How often do you have to change the cap/rotor on a normal distributor? If you have a mallory, or MSD distributor the cap/rotor will be expensive, you can get a cap/rotor kit for the opti for about $139 (just looked on Autozone's site) any of the later model distributors are going to cost if any parts are needed, pickup/control module so the budget is out.

CSR makes an electric rebuildable pump that goes on the front of the stock housing for $182 a rebuilt waterpump from Autozone is $143. The cost of rebuilding the CSR is under 50 bucks.

How is modifying the crossmember a hack job? People that have been building hotrods for years do stuff like this, so I guess they're doing hack jobs as well? Some guys don't want the a/c, thus they put on the delete pully. My brackets fit just fine with the a/c compressor still on the car. I could pull my LT1 out right now and put a TPI engine in and you would never know there was an LT1 ever in the car, then take the LT1, put it in a 4th gen and plug everything up, start the car and drive off in it with nothing needing to be changed.

 

If you put alot of money in the engine, it can be faster than an LT1, but then you could put the same amount of money in the LT1 and make it faster than an LS1...it's a never ending battle on this.
737 bucks for the edelbrock base and runners, 1200 for an edelbrock head setup, 2300 for trick flow or

from Lloyd Elliot

LT1-LE2
Head/cam package will pull from 2,300 to 6,500 RPM and should make *400 - 420 RWHP with 30/36 lb. injectors, 58 MM T.B., 1 ¾ LT’s, no cats, good tuning, etc. This will have an idle similar to the CC306 cam but will make more HP & TQ across the board. The REAL difference is the amount TQ this cam makes in the 2,500 – 3,500 RPM range compared to the cc306.

The LT1 LE2 heads consist of:
Ferrea 200/1.56 Valves
CM Retainers & 10° Locks
Comp Bee Hive Springs
205 CC Intake porting
Milling. Cleaning, Assembly
Flow about 275/190
Ready to bolt on

LE2 Head/Cam Package - $1,750 plus shipping.$1,400 for Heads only

(and these are stock LT1 castings)

As for the L98 from autozone, I read where someone bought a long block and it turned out to have crap heads on it, wrong cam and wasn't roller. They bought it from Autozone.

 

Now now klortho, lookie here, putting an engine in that weighs less, runs better, is far easier to work on, well now thats just stupid if you have to put a dent in an easily removable K member. God forbid anyone want to run something other than $10 junkyard ignition components. We all know how its easy to make 420 RWHP on a stock set of tpi heads....




Seriously now KrisW, what do you think is gonna happen when he runs up next to the guy that got out his dremel and did a little to his LT1 heads and put a cam in it ? You want to do work to the heads just to try and bring the TPI heads into a chance of comparison, the other thing you dont add into the list is all of the misc required in doing so, gaskets arent free, time isnt free, valvesprings, etc, grinding burrs arent cheap, not to mention, as i posted the LT1 heads flow similar to the edelbrock castings, outflowing them at low to mid lift, where it counts, if it was so easy for every set of TPI heads to get that flow dont you think everyone would have done it ?

Those of us who have swapped LT1's, or LS1's for that matter didnt just go eeenie meeenie miney moe i think i'll pick THAT kind of engine. The gains and ease of installation, maintenance, and performance far exceed wasting a bunch of time on the L98 platform.

 

Well, I can tell you guys are getting hurt feelings AND missing my point.

I like engine swaps as much as anyone, albeit I am not on an unlimited budget. I put weird engines in cars they don't belong in regularly. I'm not against engine swaps. I just think that if you already have decent parts to start with then there is no reason to throw it all out and start with something new. Except of course, for the romance of doing so. I am guilty of the romantic engine swap as well, but I don't do them too much now with my budget.

So, If I had a third gen with a blown engine (or just a dog) and I had an LT1 lying around, sure I'd put it in. LSx, sure, whatever. My point is that most people don't have those just lying around. A 350 chevy, on the other hand, is a pretty common piece of hardware. It doesn't cost megabucks to get one to 400 hp. If I have a good 350, I don't see the logic in trashing if for a more sophisticated chevy 350 (LT1) or LSx engine. If I have a 305, maybe.

There are so many factors to consider, not the least of which is technical ability. Many of you super geniuses on here would rather run an LSx or LTx (or SR20DET) engine than an L98, fine. Maybe the 4th gen cars (or Nissan 240 sx) are better than ours because of the updated braking technology, enhanced visibility, more readily available aftermarket, and so on. So what? We're here because we like this old 80's stuff. Nothing wrong with that.

I'm just saying it's great if you offer your opinion, but you don't have to bash mine because I don't like LT1s or Nissan engines or LSx engines.

If I cared at all about the reasonably better technology than what I have I'd drive them and ditch my old Firebirds. It's the same line of thinking.

 

No hurt feelings here, it really seems you are missing the points we've been making.

Yes he does have a TPI, yes power CAN be made using a TPI, but the fact is, for the price of just the heads and baseplate he's spent money on, a complete LT1 with transmission can be had, already pulled out and missing nothing, neither of us are saying get ripped off and pay $5000 for an LT1. If you look at used LT1 pricing, thats about what they go for with an auto, 1200-1400 is easy, it can be installed for very little on top of that. If someone is looking at switching to a manual setup the split gets even better, a typical LT1/T56 price is around 1800-2400, typically someone will spend 1400-1600 on a T56 setup just to put behind their TPI, for the extra 200-800 dollars you get an intake that outflows the TPI, no questions, hands down, you cannot argue with it. Heads that already outflow the TPI's heads, and will do evil power for a stock casting. A LOT of weight loss, set a TPI on a scale and compare it to a little LT1 intake, let alone the water pump and front drive accessory loss.

The increased drivability of the newer computer, and yes like Klortho said, most of us arent running obdII with LT1's, we're running 94-95 OBDI pcms, a quick connection to our stock thirdgen ALDL port and we're ready to change any setting in the pcm we want in a matter of minutes, shift tables with the auto are rediculous, you could easily retain the shift button 4th gen firebirds got, having a completely different shift profile at the touch of a button, with a completely independent tuning table for shift points, line pressure etc.

You seem to think we're all going down to GM to buy new LT1's when it comes to pricing, plenty is available at the junkyard, and when you start with an LT1 as the platform compared to the L98, it just doesnt even begin to compare.



Now on this section alone, hang on now, maybe a little on the hurt feelings, dont go saying i like the SR20DET all that much just cause thats whats in my 240sx at the moment, I got it for a good deal with a bad one and replaced it with another so it can get me around, dont get me wrong, its no pos, but its coming out for an LS1.

Yes, 4th gen's, and 240's may have some advantages on thirdgens in the handling / braking area, well 4th gens not so much on the handling, but the idea here is to upgrade a thirdgen since IMO its a much better platform than a 4th gen for what I want, i've owned two 4th gens, they really arent all that great imo, just make for great drivetrain donors. Better technology isnt a reason to ditch a car for another, its a reason to find the better parts and put them on the car you like.

 

Okay, well we're pretty close to the same page.

I am a BIG fan of the LT1 intake, you'll never get me to argue that point. I would rather modify one for TPI than do ANYTHING AT ALL to the stock TPI piece.

I also like the 93, 94 PCMs. I don't like the OBD2 craziness yet and I just haven't gotten deep enough into them to really get involved.

My big problem, no, MY HUGE PROBLEM, is the upfront money involved in going full tilt boogie LTx or LSx. I can build a budget engine over time and have that money in it, but not upfront. Not yet, anyway. The prices you suggest are easily double what I would ever pay for an entire car to start a project with. I just can't do it. If I use a used 350 or 400 block, a used LT4 cam, A used LT1 intake, and then some used aluminum heads, I can have a pretty stout assembly. Also, I have been known to flip an LT1 over in the pick-a-part yard in CA, tear it apart, and just take the PM rods out of it for a small block project. Yes, I am on a budget, I LIVE BY THE BUDGET. In 10 years I'll be doing LSx swaps because the yards will be full of them, maybe....

I'm going to start a new thread in engine swap about this because there are just more questions than answers for me. I hope you chime in.

 

You still can't build a TPI motor to make the power that a stock LT1 can put down, you will still be in the same price spent on parts to make the power, and still have inferior pistons, rods, and crank.

'92-93 LT1 PCM's are not PCM, they are ECM and use a chip like the TPI motors, '94 went to flash and both '94 and 95 are OBDI, '96 they went to OBDII but the conversion is very simple.

 

If it were me, I would just build the L98 into a "ghetto" LT1. Get a ZZ4 short block, (or bulid one close to it) Vortec heads, Lt1 intake, electric water pump and an LT1 cam and just tune the computer accordingly. it should make close to if not the same power as an Lt1 and it can be done fairly cheaply.that's just what I would do to leave out the hassle of swapping everything.

 

where is a good place to get an engine then? and someone mentioned keeping the L98 or w.e and using the LT1 Setup or w/e what exactly do u mean

 

You can't run the LT1 intake on Vortec heads. The intake mating flange is too narrow to cover the tall ports that the Vortec head uses

 

But with the LT1 & LS1 you can have 400hp and still get real good mpg.
Hasen't this allready been done with the TIP and LS1?

 

ok my bad, or a comparible intake I guess,lol

 

The only compatable intakes are the edelbrock vortec TPI intakes which run almost a grand for the base and runners......tad much to still have an inferior computer management system and internals.

 

Yeah, Vortec and TPI do not seem like a good match - except maybe for a pickup truck. I bet the bottom end would be good for my 3/4 ton chev!!