Martin Steel

I am seriously considering swapping in an LS1 where my mostly stock L98 now sits.
From what I have read so far, I will need a LS1 and transmission complete w/wiring ($4500??), mounting hardware $200, harness conversion $1000, fuel pump and fuel line modifications $$$?? I have been told that the 4th gen lines and tank will not fit.

Any clarification of the above would be appreciated but here is my question.
Wouldn’t a $7000 investment in the L98 produce equivalent power or better than the LS1? Is the swap becoming so popular because the maximum potential of the LS1 exceeds that of the L98?

irocz1228

If it were me i wouldnt swap to an ls1 unless you just love the ls1. Yes the ls1 will produce more power but for the 7 grand you might spend on swapping it out you can produce far more power than the stock ls1 would produce. The ls1 itself will only produce about 300 rwhp but you can get heads cam and a supercharger put on the l98 and it will produce somewhere from 400-500 rwhp. Its kind of just a personal preference issue.

firebirdjosh

iTrader: (1)

A used LS1 and T56 combo can be had for less than $4500, if you're good and do the swap carefully you can probably do it for a bit less than you estimated. LS-1 has alot of potential, and it's something "different" which everyone cares about. You could also sell your stock engine/tranny to even up the cost a bit.

91_5.7_TPI

iTrader: (2)

The good thing about having an LS1 in (even though the initial investment in the engine is alot more than just modding an existing L98) is the potential of a LS1. If you mod a L98, you can make some good power. But, the LS1 type engines have alot more potential than a TPI set-up. You can put good heads and a decent sized cam on a LS1 with an LS6 intake (which come on all 01-02 F-bodies) and make around edit-->400-450<-- at the wheels. Do the same thing to the L98, and you can make about 300-350 at the crank.
This said, if I had a L98 car, I would put in a T56, and mod the L98. But, with my current engine, I'm going to have to swap one way or the other for my to be happy. So, I'm going for the more advanced, more effecient, and more powerful engine....even though it is going to make my wallet hate me.

TransAm12sec

The LSx is overall a better design. The heads flow consideerably more stock, along with the intake.

If you were to go the head/cam/ blower L98 route, you would want to build the motor, probably have it o-ringed.

Head/cam/intake setups in TPI cars net 12/13 second ets, while head/cam setups in LS1 cars net 11 second ets.

Granted, it would take 8+ grand to get to the stock point of an LS1, however there are many more examples of people running sub 12 second ets with an LSx, compared to an L98.


LS1 head/cam cars usually make around 450 rhwp

Note- when the term head/cam is used, it is assumed supported bolt ons are used. Exhaust, longtubes, lid(airbox), ported tb or aftermarket tb, tune.




Here's a 20+ page post of LS1s rwhp numbers.

http://www.ls1tech.com/forums/showthread.php?t=281398


Personally, I like TurboedTPIs setup.
Boosted and intercooled L98 with 749 ecm
10.78@128-1.5 60ft(new best time july/06)-570rwhp@13lbs on pump gas. Est. 600+rwhp@16lbs on 100 octane. Capable of 18lbs

91_5.7_TPI

iTrader: (2)

Heh...opps. I was thinking about a friends TA. He makes 496 or so at the wheels, but that's with a small shot of the juice. Sorry about that.

Kevin91Z

iTrader: (1)

Wow, all this work done to my engine and I'm only making 300 horsepower at the crank. My drivetrain must be really efficient to translate that to 321 horsepower at the rear wheels. Not to mention the other people in our club making anywhere from 320 to 380 rwhp with 350 TPI engines.

Its my opinion that the cost and hassle of converting to an LS1 engine is not worth it. However, it is worth it to a lot of other people. If you build up a small block chevy and put a TPI setup on it, it might be maxed out at 400-450 horsepower. However, an LS1 engine can get up to 500-550 horsepower. That's the appeal. The downside is the cost is a lot more for LS1 engine parts. Its all about how big your wallet is.

91_5.7_TPI

iTrader: (2)

I wasn't saying that power can't be made with TPIs. I considered a turbo TPI for a while. What I meant is that with just heads, cam, headers (unless they are great heads and a cam to match) that TPIs would make in the 300-350 hp range. Headers, cam, heads on a LS1 would make like was said 400-450.

cam-

While I will agree the LS1 swap is pricey its not really the cost of the parts. There are many suppliers who sell stage 2 CNC ported heads with lightweight valves and springs supporting 650 lift for under 1000 bucks. Thats not pricey compared to sbc equivalents... In fact it may be cheaper.

Aftermarket FAST intakes are pricey right now but LS6 intakes are very solid to over 400 rwhp and can be had for a few hundred bucks.

Longtubes are pricey for third gen swaps but heck theres plenty of fourth gen set ups with stock manifolds in the 400 rwhp range so they are not absolutely nec.

Now if your the type that doesn't mind used parts there are plenty of deals to be had as there are oh sooo many guys playing with LS1's that seem to have deeper pockets and sell their used stuff for great deals.

Its all in the planning and goals you have in mind. To MAX out the potential of an LS1 is expensive yes. To MAX out the potential of a TPI setup is expensive but the LS1 has soooo much more to offer for the money. Not to mention once the majority of the conversion is done there are plenty of options to go from there and alll sorts of new tech supporting and promoting right now.

For me the main thing I love about the LS series engines is you can make excellent power and still retain very respectable drive ability. I like all the nice stuff AC etc. and mild manners until i stab the go pedal then i want hell to unleash and that is the one area the LS engines absolutely SHINE in comparison. I had a big block Nova that was insanely fast but no sane person ever wanted to get in it. It got 4 miles to the gallon and was a handful to drive. Theres just so many pluses to the LS motors I couldn't avoid getting one.

StevenK

iTrader: (1)

Show me a TPI that can produce the same numbers as a stock LS1 and get close to the same gas milage. Thats why I picked a LS1, you can have power, and still get around 20mpg.

91_5.7_TPI

iTrader: (2)

This is true. My friend has a Formula, a M6. He said with one tank he was able to get 30 mpg on a tank while driving the car easily. I've read about cars on LS1Tech.com running in 12s and getting 25mpg. This being highway mileage, of course.

Kevin91Z

iTrader: (1)

Who would put mild heads and cam on a TPI if they were going for more power and torque? I have stock ported Corvette heads that could be considered mild and an LT4 hot cam which isnt, and I make more than your 300-350 HP number, as I said. So did my dad's previous engine, with a ZZ9 cam and stock ported Vortec heads. I know of stock cam and head TPI's that make 300+ horsepower. I think you need to look again at the potential of TPI engines, especially since we're on a thirdgen site which promotes TPI's.
That's under $1000 for EACH head, not both. SBC heads are $1000-1300 for both heads, including aluminum. AFR's are the only ones more expensive. LS1 heads are not cheaper.
My own setup makes more than LS1 numbers and still gets 20+ mpg on the highyway. My dad's setup gets 25 MPG and makes the same power, too. Maybe you saw his white Trans Am in the Sept Car Craft? And the stock 305 TPI the car came with got 30 MPG from SoCal to Reno, NV and back.

You guys sound like the 4th genners I talk to who love to bash thirdgens. At least someone here still loves thirdgens and TPI power. LS1's are great engines and yes they are capable of making awesome power, but its just too easy to make similar power with TPI without all the cost and hassle of the swap. If I wanted an LS1, I'd go buy a car that had one.

91_5.7_TPI

iTrader: (2)

$1000 per head...sorry, he was wrong. $1100 for a pair

Man, look at your own mod list.... is there anything on the intake that is stock? I mean if you replace ONLY the heads, cam, and install headers...

I love third gens, why do you think I am driving one and swapping in an LS1 instead of just buying a 4th Gen? I just recognize a superior engine when I see one. (Besides, I have a 305TBI....not the best place to try to make power)

cam-

Whoa easy there I didnt mean to offend.Fourth gen? Never owned one. Can't stand the look of them personally. Exception perhaps for the 96-7 Camaro SS when SLP was doing them. Those are tolerable but not for my money.

Third Gen passion?? I own three. My 87 sans LS1 ( unfinished mind you after two years :P ), a crap can parts car, and one a Players car TPI that will always be TPI. I band wagon these cars around loud and proud and its not because I want cheap. I just love em. Always have. Always will. I've had plenty of other amazing cars but third gens are my favorites.

Back on point I'm not trying to ruffle anyones feathers by saying LS1's are better every which way especially when looking at dollars BUT to get equivalent performance from a TPI based sbc its no cheaper and in my opinion far more challenging to get working properly. There is no disputing the clear advantages the LSx engines hold over traditional small blocks. Lighter weight, more eficiency, better tunability, huge HP potential, combined with great durability and on and on.

I dont see how this in anyway spoils TPI or bashes third gens. Same thing that happened to the flathead Ford in the 60's is happening slowly to the sbc now. What can I say???

How does that saying go?... If ya cant beat em join em.

Best of luck whatever direction you take Martin
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Dude WTF?? Were you just in my head or something? LOL This post wasn't there when I was typing my reply HAHA!!

87CIZ

iTrader: (8)

don't forget the 150-200lb weight difference between engines. makes for a lighter car with more horsepower. For that $7k he was talking you can build a nice LS2 from the block up. further enhancing your power per cubic inch. and with almost as large of a following in the aftermarket as the gen 1 sbc you can't go wrong. especially since ls1,ls6,ls2, and ls7 parts interchange.

91_5.7_TPI

iTrader: (2)

Yea... I guess we started at the same time. I just hit enter first

cam-

Ya guess so.

As for my heads? Stage 2's used for a month for $400.00

Figure I cant lose even if I dont like em too good a deal to pass on.

As for price vs power.... check out what this thread

https://www.thirdgen.org/forums/ltx-...76-intake.html

A little searching around the LS2 LS7 section will enlighten any power hungry mind. Talk about low buck BANG!!

Heck I haven't even finished mine and already I'm dreaming of my next 6.0 build hehehe

91_5.7_TPI

iTrader: (2)

I'm having a hard time choosing between a H/C LS1 and a 400+ ci stroker L92. I'll probably build the LS1 for the 91 and might just wait til I am out of college and use the stroker in my dad's (mine when I graduate) 69 SS.

xtremeirocz

all i have to say is a tpi is crap for making power, I tried, All i have to say is a stock tpi intake will have hell getting in the 10's. I have seen dozens spend more then 7g's and get 12's in return. I spent 4k on my total swap with a stock 6litre that went 10.9's on 150 shot. I later upgraded to a 408 ls1 that is a nitrous motor and put down 330 hp and 579 tq to the wheels on motor through a th-350 and 12 bolt.

RaverRacerX

3 reasons: power, efficiency, strength
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ive seen nitrous motors put out 500+ n/a w/o being too radical. whats your engine setup?

91_5.7_TPI

iTrader: (2)

Yea, I was wondering why there was such a huge gap between the power and torque. How big of a shot are you running?

InterceptorZ28

Two things, both motors can be made to go fast, i have built L98s, lt1 and ls1 that all haul butt, anyhow, it depends also on what you know to work on them, the l98s are a lot easier to work on, plus you don't have to try to match everthing up inside a different car. And if you don't have a ls1 and you want one, I run a shop and can get ls1, NEW, not rebuilt, complete, with 12k warranty, stock of course, for about 4500, that doesn't include the computer thought, but yes the oil pan to the intake. any motor can go fast, it just depends on the builder

Orr89RocZ

iTrader: (20)

ls1's are more efficient motors since they have better ecm's and 18 degree heads.... which flow more than any 23 degree head...the design is better and an 18 degree head will outflow a 23 degree head.

now if you could build a 406 gen I small block with 18 degree heads and modded 18degree intake for fuel injection and run a FAST fuel management system, i bet you'll make just as much power as similar sized LS1's. price wise it seems like it would be similar between the two.

the hassle of the swap kinda sucks tho. the parts for the swap are near half cost the ls1 is in the first place! it seems like a waste of money to swap in a stock ls1 over a build 350-383 that has more power that costs the same as the ls1 swap.

i want to build a twin turbo L98...just for awe factor and the fact taht callaway did it for the vettes and it looked bad ***

lreflybyou

You CANNOT compare a ls1 with an l98, your talking about a conventional small block chevy to a 15* head all aluminum small block.
This isnt apples to apples..
But in this case saying it cost 5grand for the sake of arguement to swap in a STOCK ls1.
You could buy a decent 383 or 355 aluminum headed carb motor/tpi setup for that price and make more power.
Now if your talking about gas mileage then the l98 is out, but who bought a Camaro for gas mileage?
You did? Sell it and buy a civic!

People who own Camaros/Trans Ams have them for performance, because they look cool, not because they pass by Gas stations and laugh because everyone else has to fill up and they dont. Come on get real.

Hands down ill take a conventional small block over the "Ungodly ls1" any day of the week..

lreflybyou

If you have a 408 ls1 set up for nitrous or not and only put down 330 to the tires you should burn it, Im sorry but that is pathetic!I have a customer with a TPI 88 Firebird 383, small vortech blower that makes more HP and Torque than your 408 ls1 and its on pump gas!

91_5.7_TPI

iTrader: (2)

I didn't buy the car for gas mileage. But, if I can make 400 RWHP and get 25+ mpg or make 400 RWHP and get 15-20.... I'll take 400 and 25.

cam-

Better mileage = higher efficiency

Higher efficiency = more power

Whats not to like about that?

Orr89RocZ

iTrader: (20)

thats not necessarily true.

xtremeirocz

have them put it down with 17 degrees of timing , a th-350 with a 4000 stall and a 12 bolt and then come talk to me. I guess your friends tpi can put out 579 tq on motor also to the wheels and run a 11.6 on motor with only that timing and 3800lb

cam-

This thread is going rancid... why I am not sure but heres my final two cents.

There are limited units of energy per unit of gasoline. The more btu's you can extract per unit will make more power per unit than any less efficient method.

xtremeirocz

my 408 is a 9:1 motor with only 17 degrees timing in it, it would probably put down over 420 to the wheels if i didnt have a huge stalled th-350 with a 12 bolt, but im not going for dyno queen, Iwant to go in the nines with a full body ls1 conversion weighing 3800 lbs raceweight. I have already gone mid 10's on a 150 shot not running right, I now have two direct ports on my fast intake with a total of a 450 shot on it to be used as a 2 stage. This setup was never meant to be a barnburner on motor, thats why it only runs mid 11's on motor. hopefully when i get both fuel systems lined out and everything happy i can go a 9.60 or so. but we will see.

Orr89RocZ

iTrader: (20)

doesnt it dependon the gas tho? different gases (octane/etc) require different tunes to optimize... but just cuz you increase the motors efficiency to make more power doesnt mean the mileage automatically goes up. you burn more fuel more efficiently to make more power, you have just used alot more fuel and thus mileage shouldnt go up

lreflybyou

On 6 lbs on a street tire a true street tire the car goes 10.80 with a 1.8 sixty foot 125 mph....I dont see a problem in that, in a full weight trans am...
And one of my very good friends we built an all motor 383 with E-tec heads and a single 750 quick fuel on pump gas went 10.95@123mph with a 1.7 sixty in a 3700 lb stock down to the leaf spring suspension...All horsepower too no adders!
I understand it was set up for nitrous timing wise, but ls1's usually only run about 21-24 degrees of timing anyways from what I know.
Just my .02!
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Yea top fuelers are very efficient!
Thats not even close to what I would consider true...At least in the way you are talking about it...

Red92RS

Well, xtremeirocz was a huge factor in my LS1 swap and believe me he knows what he is talking about. If numbers are what you think is important than as soon as we dyno my little 346 we will post numbers, but his "low HP" 408 will destroy mine easily whether or not I make more horsepower.

lreflybyou

I know you can make big power with an ls1, I just dont know why people think they are ungodly and better than any other motor...

91_5.7_TPI

iTrader: (2)

I don't think they are ungodly or better than any other motor. I mean, there are LS2s, LS6s, LS7s, the new L92..... And coming soon, LS3, LS9.
j/k.


But serioulsy, I don't think they are "the motor". But they are the best overall engine ever produced by GM. I mean, they are reliable, they make from 300-330 hp at the wheels stock, they get good fuel mileage (even though that's a no-no for Camaros) and you can stick in a good cam and good flowing set of heads, and be in the 400+ rwhp range.
Not many engines can claim all that.

ghettocruiser

iTrader: (4)

Best way in my opinion is to get a donar car. I got a worked 99 Camaro for about the same as a lot of people pay for a motor and trans. I spent approx. 10 grand doing my car this summer. HOWEVER... I rebuilt the entire suspension, upgraded to 4th gen brakes, got all new gauges, magnaflow, and all sorts of extra stuff that you dont NEED to do to do the swap.

My vote goes LS1 if you are keeping it fuel injected. That TPI set up is just a bottle neck sometimes. Yes it looks sexy. Yes it CAN be made to make a lot of power. However you sacrifice drivability in the process. My LS1 is worked pretty good, but i drive it every day, sit in traffic with it, drive it in the rain... no issues. STILL getting 20+mpg on average.

With the amount of LS1s becoming available, the price is going down. Now everyone wants LS2s... Just look into a donar car...you will tank yourself. THere is so much stuff you can use from that car its not even funny.

If you are looking for simplicity go carbed 350 or 383 or something. If you want maximum long time potential go LS1. If you want to stay to the thirdgen roots...go 383, port the heck out of the TPI (or go to a different intake).

Have fun!

Justin

MrDude_1

the ONLY thing better about the L98/auto compared to my LS1/M6 is the price.

in fuel economy to raw power to average torque to drivability to power gained per mod to power per dollar.... even comparing replacement parts.... the motor in my car wins...


btw, if you pay 7k for a ls1 install, you're paying someone too much, and even i woudlnt reccomend it.. lol.


the LS1/M6 install can be had and done for less then the cost of a T56 and EFI upgrade...

92camarors5spd

i got my ls1/t56 or 1500 bucks with 55k miles. 650 on wiring harness. and the gas tank and lines out of a 4th gen will fit. im running them. i used spohn mounts and hawks headers with a custom ypipe to my thirdgen hooker catback. i probably spent 6000 on the whole swap. the average gas mileage i get is between 21-23mpg(with beating on the car every so often.) and i ran a 12.8 1/4 @109mph. is there anything better? lol.

chevyowner02

iTrader: (3)

I would say to go the LS1 the L98 can be made to have some kick butt hp. But with a rebuild you some times run into some snags. I had the choice LT1/LS1 and to tell you the truth if I had it to do all over I would have had a LSX.For the money spent on buying motor no tranny machine shop not to say it's still in 100's of pices far from being put back together. I could have bought a good low mile LS1 complet and got the other stuff and been done. Just what I'm gowing threw. .02

91_5.7_TPI

iTrader: (2)

Man, where the devil you get your LS1/T56?

dingle

That is pretty cheap, I got my LS1/T56 for $2500 and I thought I did good!

Orr89RocZ

iTrader: (20)

my vote would be keep gen I...skip TPI and go straight to HSR. much much better performance there. or LT1 intake conversion.

or even LT1, as they swap in fairly easy and can go 11's on stock heads.

91_5.7_TPI

iTrader: (2)

I know. I've been quoted from 4500-5500 for pull outs, even though I've seen complete donor cars for less. (I know of where a LS1/auto is now for 3500)

RaverRacerX

why such a low compression? it seems like youve left so much on the table. i know what you mean about the dyno queen thing but these motors will not kill you when you raise compression... even with a 6 speed trans youd still only put down 400ish when it should have a much higher output. most of the faster ls cars in the country have at least 11:1 and still super street friendly. i just had a buddy go 8.91 in his 408 nitrous car. he drove it home after that pass too. (ill start a new thread so i dont hijack this one)

Klortho

How about 9's with a D1SC with LS6 cam and ported heads and quote

http://video.ls1tech.com/video/f588b...5b000343bd.htm

all in a 4th gen, now imagine that in a car that weighed a couple hundred pounds less.

ghettocruiser

iTrader: (4)

Mmmm...D1SC... I want to go magnacharger on my 87 LS1...but Ide have to change a lot of stuff since my compression ratio is close to 11:1...

Anyway...LT1 swaps are becoming less relevant. Yes...they bolt in easier. But you still have to deal with all the wiring mess. And if I had to choose between some conversion mounts, maybe notching the k-member...and bolting in with major wiring to do...Ide choose the mounts and notching any day. The LS1 wiring is much simpler at least in my opinion. Get the fuse blocks, hook the batt to them, switched 12v, fuel, couple grounds, and the LS1 runs.

I know I know...you can make good power with an LT1... But dealing with the optispark drives me nuts. I like saving weight with the alum. block. I like how the LS1 revs like crazy and keeps making power all the way up.

Haha.. Ok. Im done spouting about the LS1. I think if I get it my way...my 87 wont be the only LS1 swap I own. Ide like to make my jeep an LS1 runner. Haha heck...I keep trying to talk my girlfriend into letting me put one in her Elantra. haha.

Justin

Kevin91Z

iTrader: (1)

I would say you got a damn good deal on your engine and trans, because I've spent the same amount on my L98 and T56 to run the same times and get the same gas mileage (actually cheaper because my dad is a mechanic and I helped). I've never seen an LS1 swap cost that little. Is there anything better? Yes, the look on an LS1 owners face when I spank his car because he under estimated me.

LT1's are definitely not the hot setup, because optisparks are crap, and the LT1 system is only marginally better than the L98. Put a StealthRam or SuperRam on an L98 and you have LT1 numbers.

I admire the LS1's power and performance, but its my opinion the dollar per horsepower ratio of an LS1 swap in a thirdgen is higher than that of the TPI it came with. Now, if you started with a TBI, hell yah, yank that turd right out and replace it with anything better.

91_5.7_TPI

iTrader: (2)

I'm ALL about some turd yanking!!!
I agree. If I started with a L98, I'd throw in a T56 and pop a Stealth Ram on there and go at it. I just don't see sticking with TPI when there are so many better EFI options out there. (other than it's better looking than all the others)

But, if I wanted to go BIG on the power, I'd probably buy a roller and stick in a LS_ with big cubes!!

StngKlr

I'll just have to say "Trust Me" lol. Some of us have been around here for a while with having done the LS1 swap and in IMHO the money is better spent with the LS1. The pros and cons have already been discussed several times. Its up to you with what you do.

<---- Going on 3 years with the swap, about 12,000 miles and 2 bottles in the past month lol.

I'll be helping with another here shortly, gonna try and keep it under 3.5K