robtombie

Haha got your attention...

So just a general question...what the heck are the differences in the TPI...LT1...LT4...LS1 they all are 350s (more or less)...is it just the different heads or what...yes I know there are differences in HP and TQ

99blackSS

LT1-iron block aluminum heads
LS1-aluminum block aluminum heads

I don't know what makes the LT4 different.

eagleknight97

LT4 had different heads and intake and cam and a bunch of little stuff that made it different from the LT1. It could rev higher, and was stronger. It was/is way cool!

BiGGinZ

I thought the TPI was a 5.0?

teke184

TPI is tuned port injection, and is the description for the fuel injection system, not the engine type like LT1 or LS1

TPI was available on 305s and 350s depending on your choice, i think the engine codes were LB9 for 305 and L89 for 350s...those would be the codes to compare to LT1 and LS1

the TPI was crazy fun to drive on the street, my 87 305 had about as much torque as either my LT1 or new LS1 even though it only had 200hp....
to bad it ran out of steam above 4500rpms

Lt1 and Ls1

I agree with teke184, my old 91 z 305 had just as much torque. It was so fun. The Ls1 is my favorite out of all of those motors though, and I have owned 1 of each

Ron78Z&01SS

TPI 350 motor is an L98.

A stock L98 is rated about the same torque as an LS1 (believe it or not), but doesn't come close as far as horsepower and falls on it's face past 5000rpm's.

My 85 Corvette was rated at 235hp and 350 lbs of torque according to Chevy.

My 85 Vette had pretty much "basic" bolt-ons & free mods :
(T/B bypass, gutted MAF, gutted A.I.R. pump, ram/cold air, ported plenum, airfoil, U/D pulley, chip, 170* thermo & true duals)

It dyno'd 234hp @ 4,275 & 333lbtq @ 3,200 on a dynojet.

Zerocool

i have heard that the LT4 has the downlow power of a LT1 and top end power of a LS1, which is why i wanted to make my lt1 a lt4 back when i still had my old maro. best of both worlds.

SkillZ25

So would i want to get aftermarket parts i.e. heads/cam from other companies or should I go for Lt4 stuff....well, basically what i'm asking is does the LT4 have potential to go 10's?

BiGGinZ

I believe that if you get LT4 heads then you have to get LT4 intake manifold and LT4 exhaust manifolds. I may be wrong though. If you get the full LT4 conversion I have heard typical hp #'s around 400 to the wheels or flywheel I can't remember. I believe that is with the hotcam too. If you are going to get ported heads and you don't want to convert to LT4 get ported stock heads or buy a set of new heads like these
http://thunderracing.com/catalog/?ac...vid=4&pcid=114
And the cc306 cam (also on that site) with a set of 1.6 rr's and you will never get board .

CamaroBoy96Z28

The LT4 heads and intake are meant to go together. The exhaust portion is identical to the LT1 heads and there are no LT4 exhaust manifolds on F-bodies anyway.

The TPI/TBIs were available in 350ci and 305ci form. I dont know the minor differences from the older Gen I SBCs and all that so I wont try to go into it.

The LT1/4 engines are reverse cooled and otherwise not too different from its predecessors mentioned above. The optispark distributor is a huge difference as well. LTx motors were only available as 350s in the F-body and Vette. I believe the Impala SS was only available with the LT1 as well and the Caprice got the L99 (baby LT1). The LT1/4 are iron block, aluminum headed.

The Gen III LSx engines are 346ci and share basically nothing in common with Gen 1 SBCs or the Gen II LTx motors. The LSx motors have coil-on-cylinder distributorless ignition systems, 15 degree heads and composite intake. The F-body/GTO/Vette versions are all aluminum, block and all.

There is a whole slew of details that are not mentioned, just have to read up on it.