Hey guys, my 92 Camaro z28 is my daily driver, but i want some horse behind it too, anyway i have some money to spend and was wondering if i should go with the Lt1 or stay with the TPI?

 

That's a trick question. Neither.


Sorry lol, I don't mean to be an @ss, and of course this is JMHO, but if I were to do it all over again, I'd go LSx. Even 5.3 maybe.

An LT1 doesn't have all that much of an advantage over a gen 1 like your TPI, and if you want to make some power, you'd have to ditch the TPI anyway, at least in stock form.


If I were to do it over again, I'd swap in a 5.3L, and then work on putting together a turbo kit for it after the initial swap was done. Or while the $500 5.3 was keeping me entertained, build a larger cube motor on the stand.

 

X2 on the LSx.

But if I had it to do over even being one round from number one in the points,I'd go float in a boat.It used to be hot cars was the chick magnet,but not anymore. There has been a rules change guys(damm no one told me that!!) and it's boats!!!.I might be soon 65...........but not dead yet.LOL

Just kidding of course.

 

I understand that, but this is just my daily driver for college and back home, i like horsepower but it dosent have to be stacked, thats what my Chevelle is for, i just want a motor, thats gets decent gas, can upgrade a few things, and has some horsepower.

 

Sounds like you want an LSx!

 

Yes an LT1 would be a very good upgrade, and will allow you to have more power from the start, and will get you a lot more power per $ after the swap.

An LS swap is also great, but unless your goal is over 420ish rwhp NA, chances are the LT1 will get there cheaper.

 

You should leave it stock as a DD for college

For a gas mileage/mild cruiser build Id go with a stock/mild 5.3 after school and skip the LT1 completely. Either way you cut it, a swap will get expensive

 

Well i have some money laying around and i wanna do a swap, the TPI is nice, but i think an LT1 would be great, nothing major, but i just want a few upgrades, and on the other side, after my 2 year warranty for my motor is up on my Chevelle, im making it a 383 and im going to super charge it, so thats where all my money is going during school, but like i said, i gotta wait 2 years.

 

dude get the LT intake modified to accept a distributor, pick up a small TPI distributor, dump the opti no spark, 90% of your wiring will drop right into place, small block headers will bolt right on the LT, then get Troy at Howell engine development to cut you a new chip for the LT1 on the TPI ECU, not the "greatest" setup, but defiantly easily doable. PM me, and I'll walk you through it.

 

get away from the opti-crap, and things become way easier

P.S. I too like the LT1, someday maybe I'll grow up and go LSX????

 

Modifying the LT1 intake for a distributor is going to take careful machining, plus the cost of the intake, heads, ECM, distributor, and other associated parts. All for basically just moving your torque and hp curve from the TPI's bottom to midrange to the LT's mid to upper range. You're going to sacrifice bottom end torque, which on a street car is more what you want, for upper end hp, which you really won't use as much in a daily driver.
I would suggest keeping the TPI for now, doing a port / polish job on the upper plenum, runners, and lower intake to maximize your potential, possibly go to a larger cam if you want to bump your hp. The TPI has a lot of potential, just don't expect beyond the limitations of the design. The TPI feeds air well until about 4500 rpm in stock form, about 5000 with porting, and higher if aftermarket larger runners and lower intake are used. The LT1 can feed upwards of 6000 rpm, but the short runners are designed for hp, not torque. The LT1 also has very little in the way of aftermarket support. I do agree that an LS setup is your best "bang for the buck" swap from a longevity, power, and efficiency standpoint, but it's also costly because their is a lot involved in the swap. The most cost effective method I have seen is to find a wrecked donor car, swap the entire drivetrain (engine, trans, fuel lines, fuel tank, harness, ECM, rear end, etc), and anything else you want from the donor car, then part out the rest to recoup your losses as much as possible, ultimately taking the remainder to salvage as scrap (steel is around $11 / hundred lbs right now). With luck, you can get a wrecked but running 99-up Z28 or SS for under $5000, and maybe $2000 - $2500 back in parts sales. Keep in mind this is a SLOW process, requires lots of storage space and time, and the condition of the donor car is going to factor quite a bit into your cost vs return. However, it also means you get a COMPLETE running setup from ONE source, so you have no fear of mix-matching problems that usually cause headaches in an LS swap.
IMO you're going to throw a lot of money at an LT1 swap and still not be especially pleased at the outcome for your intended use. There's a lot you can do for little cost to get the full potential out of your current setup, I'ld go that route before throwing a wad of cash at a new project.
for example, I'm making over 300 hp with a LT4 Hot Cammed .040 over 327 fed by a TPI, run by a Megasquirt-I programmable ECM. The benefit of this setup is I can tune for any changes I make myself without having to burn PROMs, I can get real time feedback from the engine and make changes on the fly, and it simplifies the wiring and control setup by using only 4 external sensor inputs (the 5th input, the MAP, is built onto the MS board). My MS-I was only $350 pre-built and ready to program, cheaper than an aftermarket cylinder head. It can also be easily upgraded to either MS-2 or 3, which let me control spark, run sequential injection, distributorless ignition setups, forced induction, and wideband O2 autotuning of the AFR table. I've run my setup for 5 years now with no problems, and have mine currently tuned as a daily driver with maximum mpg in mind...I currently get 27 mpg highway, and that's with my lockup off. Altogether I've got less than $2500 in the entire cost of my drivetrain, a 1995 Z28 posi rearend and all engine machine work included, and that's with starting with a junkyard block.

 

I think im gonna do this but i need some opinions? How good would it be? And how much gas mileage would i lose?

 

read this http://www.gmtruckcentral.com/articles/lt1swap.html $250 will convert your intake. Dude You do what you want, I caught Hell as well, but I am happy with the end result. After all it is your money and your car. If all you want is a jump in performance and millage, go for it. Maybe put a hotter cam and torque converter. in it, but that will kill millage. the LT in a Vett gets over 25mpg on the open highway, drive it "nice" it should get real close. you should not loose any millage, you should gain, more torque and Hp to pull the sled around. and I WILL be putting an LT in My Vert. as convertibles are limited in HP by design, No real frame to speak of. As I said before I CAN walk you through this, if it is what you want to do

 

P.S. you can use the TPI wiring and ECU if it would be easier for you.

 

By the time you buy everything and pay for machine work etc. Wouldn't it just be easier to buy a TPIS miniram and avoid all the hassles? I've seen them used but complete for around 850.00. Just seems like a better way to do it, how much price difference is there by converting a LT1 intake?

 

Mini ram - $850 VS LT conversion -$250 ????? yes I would love the miniram but I still have 3 kids at home. I gotta be careful with my money.

 

OK but take into account you just don't have a LT1 intake laying around, the cost of back and forth shipping, remote thermostat housing, there a lot more to it then just drilling a hole.

 

Modifying the LT1 intake is just as costly/complex as swapping in a 5.3

 

Sequential injection and electronic controlled transmission are really great improvements over the TPI-era systems.

Converting to LT1 intake is probably going to run you over $500, and won't get you sequential injection or electronic controlled transmission. And, honestly, isn't going to increase power significantly without other mods. You might as well set aside $2k if you're going to try to improve TPI.

Full LT1 conversion would get you those things, probably cost you $2500-$3500 minimum.

Full LS conversion would get you those things in spades, probably cost you $4000-$8000 (donor parts are more expensive, swap parts are required that aren't required for LT1, and exhaust is expensive - no way around exhaust expense unless you have access to tubing material, tube bending equipment, and welding equipment).

Now, be honest with yourself. How much gas can you buy for $2000? How about $3500? $8000?

What's your real motivation?

 

http://www.superchevy.com/technical/.../pro_comp.html

This a good idea?

Or should i just buy a mini ram for the TPI and do other mods later?

 

dude! I have $2600 in my K1500 LT! conversion including motor, water pump Vette accessories, injectors, headers, new gaskets, ---everything!!!! Don't listen to the easy chair builders, it is way easy, shoot my son did over half of the work, and if you use your existing PCM it would take 2 weeks max.

read my LT conversion thread http://www.gmtruckcentral.com/articles/lt1swap.html

it is your car and your money build what you want is the only advice that I can give you

 

I read your thread, how do you come up with 350 flywheel hp? You pulled 251 rear wheel on the dyno, and you estimate a 100 hp parasitic loss thru the drivetrain. Which either means you're making a LOT of assumptions about your true hp or you have 29% loss and a REALLY messed up trans / rear end. The typical loss is around 15%, which means you're closer to 295 flywheel hp if your wheel output is 251. 300 flywheel hp is well within the abilities of a TPI 350, so again I dispute the wisdom of spending so much for so little gain.

 

Ive never understood swapping TPI for LT1, L98 is about 240hp, LT1 about 275....so for a couple grand and a good amount of work you can gain 35hp....Now if you have say an LG4, or V6 or no motor at all, then by all means swap to the LT1...but if your not looking for much more hp, just some more...spend the 2 grand on the tpi motor, HSR intake, cam, full exhaust and u can have some fun...Otherwise if your gonna go through the hassel of a swap go LSX or go home.... side note I know there is more potential for power i guess with an LT1 but really its not worth the money unless you just have one laying around, and I realize the OP might have a 5.0 not an l98, i guess tht would be a deciding factor too. Really its what 5.7kid touched on, what is his true motivating factor. Explain your realistic goal of what you want from the car and then we can make better sugestions....otherwise we are all just talking from our own preferances....

 

I'll concede the HP ratings are "a lot" off, but at the time that is what the dyno dude told me, since I have been educated by Not so kind people, and my own research. with that said; the reason you don't understand? I am not sure but I'll venture a bet that you have never owned an LT1. I love my small blocks but the LT is the ultimate small block ------ In my humble opinion of coarse.

 

thank you!!!!! and amen

 

That was an utter dead end in design, features almost no aftermarket support, has little parts commonality with other SBCs besides the block and rotating assembly, has numerous shortcomings and outright poor design issues (Optispark being foremost), all for little true gain. Add to that the cost of cobbling together a complete system for a swap and machining for the OP and it's simply not worth it.

 

that is what makes us individuals, we all have our own opinion

P.S. I'm done, tyrell418 if you would like help with the LT send me a private note, I am sorry that your thread got hijacked so needlessly.

 

Look, I'm not looking for any war, and the thread has been anything but hijacked. I believe the original question was "stay with TPI or go with LT1". IMO the expense of converting to LT1 is not worth the meager gains to be had over simply maximizing the potential of the TPI he already has. From a cost-benefit standpoint he's better off with the TPI. If this personally offends you, sorry, but that's my opinion.

 

Well i want the car to be my daily driver, and have some power, i know having power is gonna cost the gas mileage, but i just want as much power without killing the gas mileage. So if i stay TPI would a mini ram decrease my gas that much? And how good is it?

 

Doubt you will lose any fuel economy with a miniram. The positive side is it can support high levels of power later down the road, if you sell car it will probably help with the sale, however until you address the cam/heads/exhaust I believe power increase will be marginally noticeable.

Maybe for now you should just collect parts until timing is better and you are able to put more performance parts on all at once. Maybe nitrous say a 100hp shot system might be better suited for what you want now.

Have you looked into a single plane efi manifold with a elbow or a edelbrock por-flo XT (looks kinda like a miniram)? I think that would give you the best bang for the buck intake wise. Your ecm and harness can run any of these intake setup.

You have quite a few options that would work well and some under 600.00.

EFI with elbow,. get correct fuel rails for it. Then run a tube to your stock air cleaner



the edelbrock proflow would need minimal work to adapt a TPI throttlebody to it and accelerator cables. I think these manifolds are about 450.00 something like that.

 

So mini rams are worthless until i upgrade the motor? That blows.. The girl i bought it from put a grand into the exhaust, and i can add heads, idk much about cams, but a new cam would kill my gas mileage huh? And if i did all that you mentioned how much horse do you think i'd increase?

 

I think you need to sit down and do some serious research before jumping into anything. I'm not trying to bash you at all, please don't take it that way, you just come across as severely lacking in information. For starters, you can't just make random changes to an EFI system without addressing how it's going to affect the programming. Major intake changes, cylinder head changes, cam swaps, even a significantly freer flowing exhaust can have big affects on the ability of the ECM to handle the engine. The ECM looks at a factory preset Air/Fuel Ratio (AFR) table, references a host of various sensor inputs to determine air pressure, air temp, oil temp, water temp, throttle input, presence of detonation, and the exhaust is sampled to determine the amount of O2 present to adjust the mixture, and determines how much fuel at any given moment to inject to achieve proper fueling. If you change anything affecting in this factory tune, like adding in aftermarket high flow heads with tighter combustion chambers, you've significantly altered the variables. Unfortunately the computer, without reprogramming, can't adjust for these new variables. Same with a high lift camshaft, a higher flowing (or vastly different design) intake system, larger injectors, and a host of other popular changes. Also be aware that any change on the intake side of an engine requires a complimentary change on the exhaust side to achieve good breathing. This goes both ways. An expensive aftermarket intake with double the CFM potential is going to do no good with a stock exhaust throttling its ability to breath, and your expensive exhaust, while better than stock, is probably not doing much of its flow potential with a restrictive stock intake. You may add both the intake and exhaust, and throw on some heads and a cam, and find your injectors can't squirt enough fuel to feed the thing. Then after fixing that problem, you find the stock fuel pump simply can't supply enough fuel. Now, some changes can be done within the realm of the ECM to handle without retuning, and there is plenty of discussion on the Thirdgen boards as to what extent you can get away with. Cams, heads, intakes, and modifications to stock equipment have all been discussed and detailed ad nauseum, so you're in the right place to begin your homework. Just DO NOT fall into the old fallacy that "expensive parts = instant power". This has been proven time and again to not be true, as there is no quick shortcut to power. Everything has trade offs, and must be balanced or you'll suffer a badly running engine at best, or a blown up one at worst.
I also recommend staying away from nitrous unless you're building a strip car for two reasons; A. It's THOROUGHLY illegal to have a nitrous bottle hooked up in a street car, and a good way to get your car seized and crushed (and some felony street racing charges on your record to boot), and B. it's costly, is a finite amount (unlike forced induction which is on-demand and infinite), and is extremely inconsistent in its power output even under tightly controlled laboratory conditions. A 100hp shot is more like a 70-130hp shot, dependent on about 50 variables. It's also EXTREMELY hard on a stock engine.
Read what others have done in the past, pick up some old copies of Car Craft, Hot Rod, Chevy High Performance, or any of a dozen other magazines (most of their old articles are available online for free, Car Craft currently has an S-10 TPI project you can follow). The point is any good build starts with good homework first. Plan out your build, properly match your parts, and you'll find you not only have a great engine that makes the power you want, but has dependability and efficiency as well. It's also generally less expensive to plan your build than to throw parts together as you go.

 

Yeah im no fan of nitrous, and im trying t find out about all this stuff and i really appreciate all the info you guys are giving me, the only cars i really know about are older muscle cars, like my 69 Chevelle, i dont know crap about this computer stuff.

 

The basic rules still apply to the computer controlled cars, you just have to have a basic understanding of how the computer does it's job. It's also why I told you about Megasquirt earlier, as it allows you a low cost way of replacing the factory ECM with one you can tune yourself, and is upgradeable down the line as you build newer engines. Look it up sometime, there is a ton of info on Megasquirt online, and the software and forums are all free. You can also use the LS computers in the same way, as they are reprogrammable. This is one of the many reasons a lot of people have upgraded to the LS platforms, because you aren't as constrained by the ECM or forced to burn custom chips anytime you make a change. Now, there are people on the forums that have built their own chip burners for under $200. Unfortunately, the chips themselves are becoming scarce, and having to burn a new chip anytime you make a change to the engine is somewhat wasteful vs a computer you can simply reprogram.

My opinion holds that your best, most economical bet right now is to keep your TPI system and maximize its potential before you jump into an entirely new setup. Then, if you still want more power, you can't beat the LS drivetrains for power vs efficiency. It isn't uncommon to make 400 hp and still get better than 25 mpg from an LS engine. I'm looking at an LS swap for when my 327 eventually wears down, but for now I have been tweaking on my TPI setup to get every last bit of power and efficiency out of it. So far I'm over 300 hp, about 400 lb ft of torque, and I get 27 mpg. I still have the restrictive manifolds on it, and once I go to headers those numbers should perk up a bit. I'm also adding in a few other goodies here and there, but most of what my setup currently makes comes from having sat down before I bought the first piece and mapping out my build on paper. I talked to my local engine shop and told them what I wanted to achieve and what my budget was, and we built a solution around that. And I'm quite happy with the outcome! There's a lot of trial and error with the Megasquirt tuning side of it, but it forces me to learn little by little, and it's really not hard once you dive into it. There are systems out there that do a lot more of the work for you, but their prices for such convenience go up astronomically. Look around, find what works for you, and build something you'll be happy with. That's all I'm sayin'

 

Put the LT1 into it.

The guys so far with the negatives have no experience, and no idea apparently.

Especially anyone who's responded to this thread with anything about them having little aftermarket support.