Still debating on whether I want to go through with my LS1 swap and if it will jutify all the work and expense. I use my car as a daily driver, and it runs 13.50's@103 as is, and with the 200R, it gets between 17-19MPG freeway with a q-jet and the 3.08 rear gears. In town it's a measely 10MPG, but some of that can be attributed to my foot, and again the gears. I'm sure if I got a well calibrated q-jet, mileage would go up without impacting performance. Anyway, having a nice smooth running motor would be nice with no wam up issues or the like.. but modifying an LS1 is expensive, even by Pontiac standards. I figure a stock '01 LS1 will give me similar performance to my 400 now, even though it may make a little less power it should make it up in weight. It's just hard to swallow certain things here and there, I mean, tunes? $500?! Virtually everytime I decide to change something? That's...crazy. Installation costs are high as well, even if I do all my own work.

Anyway, this is probabaly a fairly broad question but does anyone have any info regarding mileage, and/or performance with their stock, or nearly stock LS1's with automatics in their swaps? Particularly old unaerodynamic bricks, I don't think a light and slippery RX7 or soemthing will give me the answers I need. What's your overall feeling after the swap? Do you think the swap may look quite dated in a few years as LT1 and very much more so, TPI'd setups look now? An LS1 would shave a significant amount of weight off the front end of my car, did anyone notice a dramatic handling or braking improvement from the motor alone? I guess I just need a little bit more input to help me venture off into this new, and very UNKNOWN world. I know the car will be a vastly better machine, but I don't know if it truly justifies itself, economically speaking? I mean my current $2000 200R4 didnt justify itself economically either, but it did in the sense that it REALLY transformed the car for the better. How much power will the stock 4L60 withstand before it starts to grenade itself? Did you notice a dramatic decrease in fuel economy after swapping to a "mild" cam, say those low 220ish grinds? Anyway, thanks a lot guy's.

 

If you are looking at the swap from a purely economic perspective, then you need to give us more info. What years and make is the car? How many miles to you drive per year. If the car is a daily driver, then your main sources of payback will be an increase in gas mileage and possibly reduced engine maintenance.

Andrew

 

My old "un-aerodynamic brick" runs 100 mph in the quarter mile, gets 25 mpg plus, idles like a Swiss watch and runs a constant 190 degrees on a 120 degree day. Is the LS1 worth it?? In my eyes it certainly is! Some day I may hop it up a little but for now, the joy is in the driving of the beast, I coudn't stand to disable it for any modifications. Oh yeah, don't try to get "under" me on a freeway on ramp either, just 'cause it shaped like a brick you'll find my chassis is pretty well balanced and can get around a corner in pretty good style.

 

If you're worried about 500$ for a tune, get the setup to run a carb...I heard you get a huge power increase with the carb too...

 

i don't know what's done to your 400, but i swapped out a mildly cammed 10:1 455 olds with a mildly cammed 6.0 and there was no comparison as far as gas mileage or power. the price of tunes has come way down from $500. as far as being "expensive" to modify, what do you need to modify other than cam and maybe a set of rod bolts? a decent tune and a mild cam and you're easily making 450hp out of a 6.0. why do you need a 4l60E what's the matter with using your 200-4r? like you i stepped into the "unknown" and i'll never step back

 

Locally tunes still seem to be around $500. Nothing is wrong with my 200R but I can sell my existing drivetrain for $300, carb to pan, pulleys to the tranny, and with my new $500 headers. Right now after parting out the LS1 car, and selling my drivetrain, it looks as though I'll be money ahead putting the LS1 in my car, hence keeping the 4L60. Im not really planning on going all out on the car, but if I can get close to 370-400 RWHP without losing any drivability, and a minimal loss in gas mileage (I dunno...how does a 400RWHP LS1 act mileage wise? Does it plummet like a brick?) it will be vastly worth it. A 400 Pontiac with 400RWHP won't be particluarly cheap and it will sarifice a lot of road manners, and gas mileage will be measured in yards. So...given those goals, will the 4L60 withstand?

 

And putting a carb on the LS1 would just ruin the swap for me. Part of the very large appeal of the LS1 is the kick *** factor of fuel injection. I'm not after a drag car, just a very well balanced all around car thats a beauty to drive..and drive hard.

 

My car isn't cosmetically finished (body work stage) , no interior, and I 'm already so happy I ventured into the unknown. My '74 Camaro gets 19 mpg city/ 25 highway., runs 190 deg., with a plastic intake no HP robbing heat soak .. sorry LTI/L98, no intake icing just hotlapping dragstrip passes. Smooth as glass idle, and is atleast as strong as my '01 A4 SS ( ran mid 12's @ 111) . I have an LS6 but an LS1 with a 220-224 range cam and LS6 heads and good LT headers and you'll be way over 400 RWHP. A very difficult task for a 400 Poncho and forget about driveability. I did notice a dramatic difference in handling and you can't help but notice the lack of 300 + lbs. Perhaps it will be dated in years to come but with all the positives it seems to me I made the right choice. What's more 13.5 's @103 was moving 10 years ago but there are so many new cars now that are faster than that from the factory ... yes even a few imports !!! I was where you are years ago. I had a '79 T/A 403 (350 W31 heads) 700R4 - it ran 13.40's @103.9 .It got 14 mpg city/ 21 mpg highway. It surprised a lot of guys but once you feel the top end surge of the LSX you'll never go back. All that with light years better driveability - You'll be hooked too. Good luck.

 

a 400rwhp ls1 will not suffer from major mileage loss, provided you do not put a crazy big cam in it and drive the crap out of it with a big stall. With a stock cam, anything you do to make it breathe better (headers, exhaust, intake, Tb, will put you at 340-360 rwhp) will increase your mileage as well as power, provided you can keep your foot out of it with how it sounds and runs afterwards. A mild cam with those mods will put you a little over 400rwhp, get an awesome torque curve and with a great tune, not lose noticeable mpg over stock. ( see https://ls1tech.com/forums/generation-iii-internal-engine/454008-does-cam-bad-gas-mileage.html) Dont hesitate to go for the LS1 considering you've got it already!
olly

 

That link you posted has a lot of guys comparing their freeway mileage to the poor guy's city mileage. 13MPG isnt exactly stellar. I was under the impression in stock form they'd get ~18MPG or so in town? I don't plan on a big stall.

 

NX - whats done to your LS6? Not knowing a *whole* lot about the specifics of LS1's/LS6's, I'm under the impression the only difference power wise is the heads flow a little better (any numbers anywhere between the two?) and a slightly bigger cam, right?

 

I dont really understand your logic in getting rid of the 200r4. You said you paid 2k for it, so im assuming its pretty well built? It a 4 speed which is good. Id say keep it and ditch the 4L60E assuming that the 200r4 is built to hold more power than the 4L60E. If it cant hold any more power than the 4L60E then yea for simplicity ditch the 200r4.

 

I am still doubting the 400hp claim that you have made. If you have 400 horses from a old school 400 then I see no way on earth with that tranny and those gears that you are getting anywhere near the type of gas mileage you are claiming. And if you spent 2000 dollars on a 200r4 which by most standards are junk trannies anyway. Why would you be debating going to a much much newer and better motor? Just curious.

 

bad example.. heres a better one

 

I don't believe my "400" HP engine should be getting such bad economy, either. In reality it probabaly makes closer to 380HP, anyway. But, in any case, my mileage on my 400 has been checked, and checked again, tank after tank after tank. Thats what it get's. I've been driving it like this for years. It *should* actually be better. Look at NX and his example with his 403 powered T/A. I bet he'd drive it a little easier then I do from day to day and I'm willing to bet he kept the much more efficient quadrajet carb. My carb runs a little on the rich side to protect it from a bad tank of gas or any detonation concerns, and the Edelbrock is by no means well suited to low speed operation with the fairly large primaries, especially when it's sitting on top of a Torker 2 which is a fairly large single plane street intake. Why is that so hard to believe? And why is the 2004R a "junk" transmission? Someone better tell all the GN guys their trannies are "junk". When built right they are stronger than a 700R4/4L60E and have far superior gear spacing. I can get most of my money back selling the 2004R as a few guys here in town are very interested in my old drivetrain. It's more than proven it's reliability on several thousand mile trips, and again, is my one and only daily driver. The switch to the 4L60E is simply for slight conveniance and the superior feel of an electronic transmission.

As for why the debate on going to a superior motor? Cost. Value of the car will probabaly plummet. It'll be a car noone wants but myself. Not smart economically. Pontiac guys like Pontiac motors. Chevy guy's like Camaro's. Cost of modifying the LS1 is quite a bit more than the Pontiac. And then theres the sound of an LSX. On top of that, I think about it down the road. A TPI swap in 1993 was a pretty damn cool thing to do. By 2000, people thing "WTF did he do that for? Should put in an LS1" I see it all the time. Me, I don't critisize because I *know* why he put in the TPI and I can appreciate the car, especially for the time when it was done. I just kinda think that maybe in 5-10 years, people will be saying the same about LS1 swaps. The original type motors will forever and always be cool. That pretty much sums it up.

 

"Value of the car will probabaly plummet. It'll be a car noone wants but myself. Not smart economically. Pontiac guys like Pontiac motors. Chevy guy's like Camaro's. Cost of modifying the LS1 is quite a bit more than the Pontiac. And then theres the sound of an LSX. "

Don't be so pessimistic. Do you think the vintage Camaros with LSx motors have lost their value? I doubt it. As for the Ponitac motor thing, heck my LS1 came out of a Pontiac TransAm. Who is to say your's didn't too? A TransAm with a late model TransAm motor, sounds pure Pontiac to me. Just don't put Corvette Fuel rail covers on it! I agree with you on the cost of mods, but there are other advantages as you mentioned like better fuel mileage and drivability. Not sure what you mean about the sounds they make. The ones I have heard with a good dual exhaust just sound like a healthy V-8.

Anyway, hope you go through with your project, I think it will be bitchin'

Pat

 

"superior feel of an electronic transmission", no offense but i'm still laughing . i hate the 4L60E in my truck, it's never shifted the same way twice. if it wasn't for the overdrive i'd put my th-350 behind the 6.0L again.

 

Come on, a 400 hp LS1 on stock internals is dead nuts reliable. Factory roller hydraulic cam, lifters, roller rockers, all aluminum cuts a few hundred pounds off... Nobody's forcing you to do it, its your decision. I've got the original drivetrain for my '67 RS camaro, and its sitting in the garage on a stand. I dont give a flying **** that my car's not original, i made it so it can be put back, but It's my car, i can have it however I want. Shaving 300 pounds off the front of the car, tripling the fuel economy, greatly improving the driveability and reliability, and adding immensely to the "wow" factor was enough to convince myself of the LS1. And dont compare an LS1 to a TPI smallblock. The TPI is a SBC with a special intake. No awesome stock heads, no 6 bolt mains, no all aluminum block and heads, i could go on. If someone looks under your hood, and say "grr thats not a pontiac motor, thats sin, you're gonna burn for that," who cares? If it makes you feel better, as someone said above, get a Trans-Am dropout
i'll get off my soapbox now...
olly

 

It is a Trans Am dropout, all donor stuff is from an 01 T/A I picked up a week ago and was intent on parting it... to fund the P400 some more. But then all the benefits of the late model really hit me. I wanted fuel injection, I wnated a roller cam, I wnated aluminum heads. Check, check, check. I DO want to do the swap. It's kinda like a really hot girl with an STD, LoL. No, but really, I am well aware of all the positive points.

As far as the Pontiac motor, there hasn't been a true one built since 1979 with the last of the 400's. I know for a fact that Pontiac guys for the most part will shun my car...which is fine, whatever. To them, an LSX IS a Chevy motor, and no amount of corporate convincing will convince them otherwise. It's on the same level as putting a Chevy in a Ford, or a Ford in a Mopar or something. That said, it is my car, I DID save it from a demo derby and I have brought it back. It's so far from a stock restoration that it's not even funny. The old guys still trip over wheels that are bigger than 15", but those are the guys who have the money, and who would buy the car if it ever came to selling. I will really limit my market by doing the swap to guys who are looking for a bad *** looking older car that is perfectly and completely streetable in the daily grind, or to soemone who just thinks it's cool. Unfortunately, everyone wants a Camaro, so that already hampers Bird prices. Either way, I doubt I'll ever sell the car as I love it so freaking much anyway so it's not really consequential. I'm just weighing the goods and the bads, as someone indirectly asked.

Anyway, Ive never ever ever been in an automatic LS1 car before. Ive been in 6 speeds, and they sure don't *feel* fast whatsoever do to the incredibly smooth power delivery. They do run the number though. My buddy just today bought a 2000 Trans Am with an automtic so Im going to go see how much I like it tomorrow, performance wise. Funny, its the exact twin of my parts car, down to the options and color.

I have a feeling I'm going to end up spending a lot moe time here on LS1Tech than classicalpontiac, thats for sure. I just need to start parting out this '01, and I'd like to keep it local. Shippings a PITA.

 

OSF, The LS6 stock dyno's in the 350-355 RWHP range . Improved head flow and valve train and more aggressive cam allow 500 rpm usable over the LS1 . My 01 SS dyno'd 308 RWHP stock, with air intake lid and exhaust 327 RWHP, LT headers and ASP pulley 355 RWHP. All that and getting 19 mpg city/ 28.8 (highest) highway mpg. A friend offered me $20,000 for my car (74 CAMARO) !!!! Now granted he's crazy ( he's had a '69 " been there done that" he says, he's seen my bodywork on my '79 but when I showed him the engine he flipped out- that's what hooked him. Ofcourse this a 4 wh disc 14" fr 13 " rr , big C5 Z06 tires & wheels. upgraded suspension and interior - when finished will be a true stunner when completed. Yes my 01 SS was the fastest , best handling , braking , miserly car I've ever had but to me it lacked character - crappy factory paint , dime a dozen - they're everywhere. What I wanted to do was get a 2nd gen and bring the best of the new car into the old ( like Ford did with the STANG) . If your conversion is done right it'll be worth more than stock as long as it's not a rare car. I've seen plenty of conversion '69 Camaro's beautifully done going for well over $50 k some for over $ 100 k. Now at Barrett- Jackson I've seen original '69 Camaro's Indy pace cars go for $40k. Let alone the stock 327/350 high # Camaro going for $20-$25 k for a clean model.
As far as your car - keep the 200r4 , it'll bolt up with an adapter, change the gear to 3.55 or 3.73. Case in point: my '79 T/A had a 700r4 +2.41 gears for a week before I put in the 3.73. My mileage sucked! My vac. gauge had me below 5" on any hill I was taching 1300 at 70 mph - the reason .. my cam ( mild 204-211) wasn't making power that low an rpm hence terrible mileage. When I went to 3.73 I picked up almost 8 mpg! As far as your engine output - dyno it on a chassis dyno. But get ready to be disappointed if you've never done it before. At 380 flywheel expect around 320 RWHP. What kind of car is this? If you have 380 hp you must be in a heavy car to only trap 103 . My heavy '79 T/A was around 320 flwhl HP and it trapped 103.9. Granted if you had 3.55's you probably trap 105. Whatver you do good luck but if you go into the unknown you won't tire of telling us how glad you are that you did. Just take you're time and do it right the 1st time.