Tpi Or Lt1

[FormulaLT1]

OK well do a mild port Job on LT1 heads and you will be right there and do a LT4 Cam install and stage 3 Port and polish job and you will be in the 500 Horse neighborhood. Also there are tons more people that have taken out a small block from a 3rd Gen to install a LT1 than have taken out a LT1 or LS1 to install a Gen 1 and as for how many race cars have installed a first Gen and how many have installed a LT1 lets look at the number of decades the first gen has been in production Vs. the 5 year run the LT1 had and your talking about reverse cooling like they relocated the oil filter. The reverse cooling was a major design improvement one that will allow you to runs compressions unheard of with a first Gen and will provide many more options for the true gear head. Although the Gen 1 Small block was the whole basis for the LT1.

[CORE402]

Stock for stock I would take the LT1. They come with 6 speeds, have better + aluminum heads, much better looking (in my opinion), and (not really not that big of a deal) there is the reverse flow cooling.
IROC is correct in all of his statements when it comes to the TPI motors. Again, both are too much of what they are. The TPI's runners are too long killing upper RPM power and the LT1's extremely short runners kill lower RPM power. Both are great platforms for power. When it comes to modding engines the Gen one motor will be the cheaper engine of the two. One can cheaply install vortec heads, as IROC stated, or even go beyond that with some AFR, World, Dart, Trick Flow, etc and still be street legal. Your choices are more expensive and few on the LT1 motor. The advantage with the LT1 is that is comes stock with pretty good heads. These are pretty good right out of the box and you dont have to hassle with ripping off older heads. The LT1 to LT4 conversion is extremely expensive with little gains in comparison to the modding of a Gen I engine where one could purchase the Holley systemax kit for only 1400 dollars and get the same power numbers as the LT4 conversion with 1100 dollars to spare. Just a matter of prefferance. If you are willing to wrench on the car a lot then the older Gen I is the cheaper platform to mod. If one just want it to be done and wants to go fast get the LT1. Hell now there is the STS turbo out there. The LT1 is the perfect platfor for it too.

[FormulaLT1]

I'm sorry but the only thing you said that is true is that the runner hurt power up top on TPI's, Besides that nothing else is true. You can buy a LT1 off ebay or from www.car-parts.com for like $550.00(I know this is true cause thats how I bought my second motor and I had like 3 to choose from) and when you look at the cost of Vortec heads. When compared to LT1 it isn't cheap. no good heads are cheap and LT1's have a huge aftermarket, Heads, cams and everything else you have so many choices I don't even know half of them and had too many choice. Also you can buy a LT4 hotcam Cam ground to specs and port the stock heads to create a much better flow than the LT4 ones. the cam would cost about 130-140 on ebay and the STS Turbo is not worth the money compared to the number you can get out of just a cam/head port job with some PCM tuning. Also you can put a 6 speed on a TPI as well so that is no bonus to anyone they have the same bolt pattern. Also when you look at the cost of changing the intake system and heads to provide the same width powerband a LT1 has stock you will see its just cheaper to buy a LT1. Also the LT1 does not lose a damn thing down low. it has damn near dead on torque numbers down low with a 350 TPI maybe 5-10 Pounds nothing major although I have to admit it does feel like alot more than that but dyno's don't lie.

[CORE402]

Well when it comes to the LT1 I wasn't lying about its short runners. The TPI engine is a shitty engine, stock, to compare the LT1s power to. 330lb-ft? Any crappy V8 can pull those numbers. TPIs only pulled 15 seconds flat stock not much to brag about or to compare to.
The reference I used was straight from lingenfelter's book. I do agree with you that the LT1 is a great engine to start with and can be made into a bad ass engine. The aftermarket I was reffering to was the LT1 to LT4 conversion that costs what like $2500 for only 420hp? Trick Flow offers a 420hp kit for only $1500 for the Gen one and that includes everything you need for the conversion. And by the way just cause you can get the engine for cheap doesnt mean the add ons are going to be too. I once bought a 402BBC for only 100 dollars. The thing had rods, pistons, crank, heads, manifold, carb, everything. Just needed to go to the machinist and it was ready to go. But as we all know BBC parts are expensive as hell.
When I spoke of the six speed being in a 4th gen I meant stock. Of course a six speed will go into a 3rd gen. Hell if I really wanted to I could put a jet engine into my Camaro, or why buy a vette when I could turn my 73s suspension into a vette's? I was reffering to stock.

[FormulaLT1]

TPI are great IMO but there only downfall is the long runner's which are great for low end torque and look really cool also again just my opinion but the LT1 doesn't have short runner. It has a direct one piece intake manifold that is a very effiecient design because it provides the intake ports imediate access to that air. Also if you owned a LT1 which I take it you don't. you would know right away that while the LT4 package provides impressive numbers and is a manufactor offered package which is always a bonus is not the best way to go because of the parts necessary to change to use this kit on early LT1's as well as the cost of changing to the LT4 intake manifold and the need to change the heads to use this package to the LT4 heads. you would be much better off by buying a custom ground LT4 hotcam specs and then just porting your heads and intake manifold to match (which when ported provides alot better flow than a unported LT4 intake manifold). the cost of doing this while providing more power is only around $500. if you know how to port yourself. and this includes the new pushrod and roller rockers and valves. I have done this and the power is super impressive and when PCM is programmed to match and you install a set of gears to go with your new power set up. there are very very few cars for 10 times that invested that can keep up let alone beat you.

P.S. - Good luck getting a Jet Engine to bolt up but the 6 speed will.

[CORE402]

Hey man I agree that it is a good engine to have, the LT1, and I too believe one should just work with the LT1 heads. Just change the springs and put in a nice custom ground cam and you are set. Whenever you can do machine work yourself you can't include that in your price cause not everyone has that ability. When it comes to the LT1s short runners Lingenfelter stated that in his opinion they were too short and he made his own manifold for the LT1 which he felt gave it best low end and top end compromise.

[FormulaLT1]

Well it wasn't really a area that needed improvement but you also have to look at who's stating this and that they are trying to sell you something or tell you why there product is better. 99% of discussions relating to the intake manifold used on LT1's is related to what a improvement it was over the TPI system used although I must admit my TPI Vette's sure felt like they had alot more down low

[CORE402]

Hey so do you know if there is a way to convert an LT1 to a carb setup?

[FormulaLT1]

I have never seen one but I think I have heard or read something real quick one time about someone doing it but I don't see the point and as you know anything is possible but whats the reason in alot of it.

[CORE402]

Oh the Lingenfelter book is nothing about buying anyones products it is about modifying small block chevys even LT1s!

[CORE402]

well say someone like me wanted an LT1 but not all the funky fuel injuection. I've seen the LS1 conversion and I was curious if an LT1 conversion was out there.

[FormulaLT1]

Never looked into switching to a carb so couldn't tell ya but tell me again how lingenfelter isn't selling anything http://www.lingenfelter.com/lingenfe...=16&pf%5Fid=41 . If he didn't state there was room for improvement why would he be able to later say there was a need to change it, I'm not saying this is his only reason for adding this but I bet it had something to do with it because almost every other auto experts praises the Manifold

[CORE402]

In the book he said both the TPI and LT1 were too much of what they were. Lingenfelter really liked the L98 Corvette heads though that is about all he talks about in his chapter on cylinder heads. He stated with some porting of the intake port from 163cc to 180cc you could up the .500" lift CFM to 250!

[DVS LT1]

Originally Posted by 89IROC&RS

the TPI is limited by its heads, the LT1 has much better ports. Bolt on a set of vortec heads onto a TPI setup (Vortec heads use LT1 ports) and the TPI 350 will make 340-350hp. which trumps the LT1.

The LT1 is limited by its heads as well. Bolt on a set of LT4 heads with matching intake and you've got a 350hp engine.


I like to take the same approach when comparing the LT1 to the LS1. Even the heads up, then swap in a multiple coil (opti delete) ignition system, and watch what the Gen II engine does to the Gen III. Why not even things up further - give the olde Gen II roller rockers, 26lb injectors, aluminum driveshaft, etc... the newer design isn't all that! lol

But ya, heads make all the difference in the world.

[FormulaLT1]

Originally Posted by DVS LT1

The LT1 is limited by its heads as well. Bolt on a set of LT4 heads with matching intake and you've got a 350hp engine.


I like to take the same approach when comparing the LT1 to the LS1. Even the heads up, then swap in a multiple coil (opti delete) ignition system, and watch what the Gen II engine does to the Gen III. Why not even things up further - give the olde Gen II roller rockers, 26lb injectors, aluminum driveshaft, etc... the newer design isn't all that! lol

But ya, heads make all the difference in the world.

All good points Randy but I think that a simple port job and the LT1 heads would make all the difference in the world but I have been thinking about that coil pack they use to replace the opti distributor and even though its a very efficient design wouldn't it leave the major drawback to the opti anyway which is the optical sensor which it still needs to use to know when to fire the coil to that relating piston and since the optical sensor would still be located directly under the water pump what would be the advantage of switching after all its not the electrical charge that sets the code or messes up the timing , its the optical sensor. I think a electrical radiator mounted motor/pump would improve the problem and provide less water access to that area and free up some horse's by not having the cam drive the pump either but they don't have anything like this yet. Just a idea though.