mods to beat an LS1
#1
mods to beat an LS1
So I know i am a noob...but only to the board. I have been a member to LS1tech.com....thirdgen.org and iroczone.com for quite a while. I have a 89 RS which is ungodly slow, and was thinking about a swap. I was gonna do the LS1, but i decided that it was WAY to much work for what i would be getting and also money. So now i have opted for either the LT1 or a ZZ4 w/a HSR...i have been searching for about an hour and a half on the sight reading about peoples mods and dynos and results from races against LS1s. Basically if i have a fully built suspension, al. driveshaft, built 4l60 tranny, and a car weighin about 3250. what would i need to do to the LT1 to make it run w/the modded LS1s. I was thinking low 12's high 11's N/A /stock bottom end. I was gona start w/hooker lt's, trickflow elbow, ud pulleys, and then of course head/cam package. I just cant figure out if i should get the heads ported. get the LT4 heads or some other aftermarket ones. I have seen a lot of stuff bout the hotcam and the other one...cant remember right now its like C033 or something. People were saying they wished they would have bigger for their future mods...any help would be appreciated
#4
Yeah, it can be done. A set of heavily ported LT1 heads and a bigger cam with full suspension will get you into the 11's NA, but you may break the rearend if you aren't careful. You're also going to need a higher stall converter, probably around 3000 RPM.
#5
I suggest finding an LT1 in a junkyard in good or bad shape complete and having it rebuilt with forged pistons (summit engine rebuild kit for forged Speed Pro pisonts is $530). Send the heads to Lloyd Elliot as there have been numerous threads on how well Lloyd ported LT1's flow (something like 270ish cfm intake). Get the GM 847 cam; it's a little bigger than the CC306 and makes slightly better numbers throughout the powerband. With this combo, you'll have a fresh 400+ rwhp with a tune and pistons that'll better handle a small dose of giggle juice.
Jason
Jason
#6
yah i was thinking of starting w/picking one up from a junkyard and doing a rebuild...would it be better to just bore it to a 355 at the same time? I dont know to much about extensive engine work like head work and cam specs things like that, but you say he ports the LT1 heads....so does that change the compression at all? and is that actually better than aftermarket heads??...sorry i sound like a noob, but im only 17 and dont really have anyone to help me out.. i know alot about body work and cosmetic stuff...and some power adders but def. not heads and cam
#7
Generally porting aluminum heads doesn't affect compression much. Chamber work will slighly lower the compression, but normally the heads are then shaved slightly to make sure they are completely flat and smooth. Usually you break even (or close enough to it). Also, Lloyd can design a custom camshaft to match any of the heads he does. Prices for a custom cam are usually about $50 more than an off the shelf cam (Comp. Crane, etc...), and they work alot better than off the shelf cams in nearly every case.
I don't know that you're going to find much in a junk yard. Most LT1's are removed as soon as the car arrives and sold almost immediately.
Usually when you rebuild a motor, you have to bore the cylinders to make sure they are round instead of oval shaped (similar to shaving the heads for flatness). So going to a 355 isn't a bad idea. A better idea is to bore the motor as little as possible to preserve the strength of the side walls, so going as little as .010 or even .005 would the best thing if the block allows for it, and the machine shop can do it.
I don't know that you're going to find much in a junk yard. Most LT1's are removed as soon as the car arrives and sold almost immediately.
Usually when you rebuild a motor, you have to bore the cylinders to make sure they are round instead of oval shaped (similar to shaving the heads for flatness). So going to a 355 isn't a bad idea. A better idea is to bore the motor as little as possible to preserve the strength of the side walls, so going as little as .010 or even .005 would the best thing if the block allows for it, and the machine shop can do it.
#8
http://cgi.ebay.com/ebaymotors/ws/eB...category=33615
Just get something like that and throw an intake/headers/carb on it and you got yourself a ls1 killing machine. It's not emissions legal, but if you are looking for 11's NA, your lt1 cam/heads/headers setup isn't gonna be legal anyhow.
Just get something like that and throw an intake/headers/carb on it and you got yourself a ls1 killing machine. It's not emissions legal, but if you are looking for 11's NA, your lt1 cam/heads/headers setup isn't gonna be legal anyhow.
#10
I had an '89 Firebird Coupe with a 305 TBI. I had about 7 different combo's in the car, two of which you may be interested in:
13.30 at 106 mph: 350 with 9.3/1 compression, Holley 670 cfm TBI, stock computer/fuel pump, Edelbrock TBI intake bored to 2", TFS Twisted Wedge heads, ZZ3 cam (208/221), Edelbrock junk TES headers, 3" SLP cat-back, 2500 converter, 3.42's, full weight with A/C, polyeurethane bushings in trailing arms and KYB rear shocks, street radials.
11.09 at 122.5 mph: 383 with 11.5/1 compression (93 octane no problem), AED Holley 750, Edelbrock Victor Jr. intake, AFR 210's out the box, 847 cam (234/242), SLP 1 3/4 shorty headers, 3" SLP cat-back, 3200 Vigilante converter, 3.73's, full weight with A/C, poly bushings in trailing arms and KBY rear shocks, BFG drag radials.
The first combo would run neck-and-neck with a stock LS1, not bad for TBI with stock computer, low compression, and junk headers.
The second combo is very simple and worked well. Compared to an LS1, well, ya' know. . .
Mike
13.30 at 106 mph: 350 with 9.3/1 compression, Holley 670 cfm TBI, stock computer/fuel pump, Edelbrock TBI intake bored to 2", TFS Twisted Wedge heads, ZZ3 cam (208/221), Edelbrock junk TES headers, 3" SLP cat-back, 2500 converter, 3.42's, full weight with A/C, polyeurethane bushings in trailing arms and KYB rear shocks, street radials.
11.09 at 122.5 mph: 383 with 11.5/1 compression (93 octane no problem), AED Holley 750, Edelbrock Victor Jr. intake, AFR 210's out the box, 847 cam (234/242), SLP 1 3/4 shorty headers, 3" SLP cat-back, 3200 Vigilante converter, 3.73's, full weight with A/C, poly bushings in trailing arms and KBY rear shocks, BFG drag radials.
The first combo would run neck-and-neck with a stock LS1, not bad for TBI with stock computer, low compression, and junk headers.
The second combo is very simple and worked well. Compared to an LS1, well, ya' know. . .
Mike
#11
Are you trying to get into the 11's ... or just beat an LS-1 .... or just beat an LS-1 in general...
Secret is you don't really need much to beat an LS-1 ... not allot of crap under your hood... you just need the right stuff under your chassy. A good suspension setup and weight adjustments can be pure hell to the unsuspecting. That will get you half way down the track... what ever happens with your RPM band after it starts falling off is up to you and the skills of the other driver...
Secret is you don't really need much to beat an LS-1 ... not allot of crap under your hood... you just need the right stuff under your chassy. A good suspension setup and weight adjustments can be pure hell to the unsuspecting. That will get you half way down the track... what ever happens with your RPM band after it starts falling off is up to you and the skills of the other driver...
#12
Well, i always thought it would be nice to beat those LS1 guys, my friend has a L98 thats running 12's and i been w/him in a couple street races. You should see those guy's faces in disbelief when they get pulled....its so funny. At the same time my goal is to be running low 12's/high 11's w/out induction or a bottle (i would still use a bottle just in case on top of that lol). ..Engineer mike, sounds like you had a nice set up...w/REAL nice slips. only thing is that i would really like to run FI. I been thinking, and if i went LT1, i would bore to a 355, port the heads, get a cam, UD pulleys, headers, intake, and i already have suspension. But the same time i can just buy an LS1 donar car, and do a full 98+ interior swap as well. I like their dashes more than 93-97s. Then get MTI stage 2 heads w/an X1 cam, supposedly good for about 440rwhp. The only thing w/that is computer and wiring, and then motor swap is not direct. Which is more money, thats the only thing holding me back. Whos knows, So does the LT1 really lose that much up top? i know they are supposed to rev to 6k right? why would get be getting pulled by LS1's then??
#13
At low RPM's, LT1's produce more torque, Faster ... So up to about 60 or 70 MPH its a fair run with an LS1. But LS1's have a far superiour cylinder head design which flows way better at high rpm's ( 4500+ RPM ). So a stock LT1 may take an LS1 out of the hole, but once they wind out a gear or two and are in their topend, they pull like a mother. LS1's respond better to mods as well. However, if your lookin to get into times like you stated, it would be cheaper to just do an LT1 with forged internals, runnin some boost. Boost makes high hoprsepower so much more streetable. With Heads and a cam like what you mentioned, you probly have trouble making vacuum for brakes, and it would suck major dick in traffic cause it would probly want to overheat. HUGE cam and heads are a no-no for a street car. Moderate heads, and a supercharger though Or a nice twin turbo setup
#14
so that head/cam package isnt very "streetable"? You think i would probably end up SAVING money for the LT1 rather than the second route? Because i know if i always wanted to go faster, the LS1 has it in it, but does the LTx?
#15
LTx motors have alot of untapped potential. They work really good with nitrous and forced induction if you can drop the compression ratio or get a decent piston. The heads aren't bad for a factor casting, and the intake can support them to 7000+ RPM (the computer usually quits before the intake does). Plus they are getting cheaper every day and the aftermarket is starting to respond to them a bit more than in past years. No doubt the LSx is the future, but the SBC has been around for 50+ years now and it's still probably the most used motor for all kinds of motorsports.