Tpi Or Lt1

[CAMAROPRINCE28]

i am considering buying a 1993 lti or an 1991z28 tpi. Which would be the better bang for the buck and i do not intend on drag racing but would like to have enough power to take the imports out with just maybe a flowmaster and k&n. Also i would appreciate anyone who has the performance figures for a 1990 iroc or 1991 z28 tpi.

[cuda_dude]

a 91 z28 is rated at 245hp(if it has the 350) and the 93 would be running 275hp with the lt1. I would go with the lt1 if i were you due to it being reliable, very strong, and easily modable.

[cuda_dude]

Yr Modl Tran. Engine CR Disp. HP Torque In- Manual Auto
90 IROC M5,A4 LB9 V8 9.3:1 5.0 (305) 210@4400 285@3200 TPI 3.08--- 2.73 ----
90 IROC M5 LB9 V8 9.3:1 5.0 (305) 230@4400 300@3200 TPI ---- 3.42 ---- ----
90 IROC A4 L98 V8 9.3:1 5.7 (350) 245@4400 345@3200 TPI ---- ---- ---- 3.23

91 Z28 M5,A4 LB9 V8 9.3:1 5.0 (305) 205@4200 285@3200 TPI 3.08 ---- 2.73 ----
91 Z28 M5 LB9 V8 9.3:1 5.0 (305) 230@4200 300@3200 TPI ---- 3.42 ---- ----
91 Z28 A4 L98 V8 9.3:1 5.7 (350) 245@4400 345@3200 TPI ---- ---- ---- 3.23

[CORE402]

I would go for the LT1, hands down!!

[justlearning]

the lt1 has more stock power and is stronger but the tpi is cheaper to upgrade i belive as far as the engine mods go...but if u got the money get the lt1 and go w/ the lt4 upgrade...i have no clue but is the lt1 the one w/ the computer controled trans

[89IROC&RS]

if you are just doing stoplight runs from a dig, id go TPI, but then i also hate the LT1 engines, just a personal preference deal. but if you are gonna do standing start, short distance races, the TPI has more low end grunt, and will accelerate faster but will sputter out and slow down after about 4000rpms.

[Jm93]

IF i hadnt known better, id think you were comparing a Tuned Port Injection system to a
5.7L LT1. in wich case i would go with the LT1, becuase it takes more then a fuel system to move a car.

Seriously though, the Lt1 will probabley do you better.

[ugk]

Go TPI, Third Gens look better. Performance wise, the LT1 is superior to the L98. It has a much better top end, while still having enough low end grunt. You can't go wrong with either car.

[FormulaLT1]

Originally Posted by 89IROC&RS

if you are just doing stoplight runs from a dig, id go TPI, but then i also hate the LT1 engines, just a personal preference deal. but if you are gonna do standing start, short distance races, the TPI has more low end grunt, and will accelerate faster but will sputter out and slow down after about 4000rpms.

Oh 89, my LT1 said it don't think much of you either and it also said I was way sexier than you too but I still like you and happy new year.

Originally Posted by justlearning

the lt1 has more stock power and is stronger but the tpi is cheaper to upgrade i belive as far as the engine mods go...but if u got the money get the lt1 and go w/ the lt4 upgrade...i have no clue but is the lt1 the one w/ the computer controled trans

93 F-body LT1 had no Computer controlled tranny but in 94 and up. They all came with the 4L60-E PCM controlled Tranny.

[89IROC&RS]

watch which engine you call superior, 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.

oh and formula, your LT1 should know why i dont like it, it never called me back after that night at the junkyard. oh and happy new year

[89IROC&RS]

oh and with superiority, i also preferr the TPI over the LT1 due to the reliability of the TPI system over the LT1 system. the LT1 has leaky water pumps, and very fragile optispark ignition systems. The TPI uses tried and true technology in the form of a HEI distributor and old style waterpump. this appeals to me.

[FormulaLT1]

The TPI while a solid block and torque animal is nowhere as effiecient as the LT1 block and your right if you change to Vortec ("LT1 Style" heads) and change the intake manifold/shorten the runner's with a "LT1 style" short type and change the cam to the more aggressive "LT1 stlye" specs. You will have a very dependable block with "LT1 style" power but then again you could just buy the LT1 and save some money. Also your right the water pump placement was not the brightest idea GM ever had but since its cam driven they were pretty limited were they could put it but I disagree with the opti spark comment. The only downfall with the opti is that its located under the waterpump and if the water pump or one of the hoses leaks or a waterpump bearing seal come undone it will cause a problem but if you have a healthy water pump and well sealled fastener's the opti is a very good design and provides very accurate timing that never has to be checked and will never go out of specs. As well as a much more efficient cooling design to run more boost or higher compression ratio than your standard smallblock this is why so many 3rd Gens are running LT1's but when was the last time you saw a hot rodder at the track in a 4th Gen running a smallblock Gen 1

[FormulaLT1]

Also my LT1 said she didn't call you back cause your crank didn't spin her flywheel. Her words not mine.

[89IROC&RS]

Originally Posted by FormulaLT1

Also my LT1 said she didn't call you back cause your crank didn't spin her flywheel. Her words not mine.

LMAO!!!!!!!

[89IROC&RS]

But i do have to call out a few points, as far as the efficiency of the block design, the gen I and gen II blocks are nearly identical, the only difference is the reverse flow cooling of the LT1.

Optispark, i totally agree, it is one of the greatest concepts in design, foiled by real world situations. the fact is that while it is an awesome device, it is extreamly fragile, and when it fails it really fails. thats why i dont like it.

in regard to changing the TPI to "LT1" specs, all i was talking about were the heads. leave the TPI cam, the long TPI runners, and it will make the 340hp, which is not LT1 style power, its 65hp more.

oh and do you reallllllllly want me to waist all the bandwidth and time listing all the fourth gens with Gen I engines???/?? when was the last time you saw a LT1 in a professional race car? i GUARENTE there are no where near as many LT1's as Gen I blocks.

You see the LT1 in the third gens, because its cool. not unlike putting an LT4 or even an LT5 or LS1/LS6 in a third gen.