Building a LS400 race car... informed opinions needed...

[Spinnetti]

Hi folks, new here.

About me: Been hotrodding Toyotas since 1984, and racing them since 1987. I've been road racing a 85 Corolla GT-S for 17 years. I work for Toyota's US HQ, and we have a two car team running the "24 hours of Lemons" too. For fun, I decided to build a LS400 for Lemons events (google it if you haven't heard of it - its a blast).

Anyway, So I bought a decent 91' LS (air suspension) and have a bunch of questions. I used to drive one of these as my street car, but have little info if this thing can be hustled down a road race track. I'll try and post my various questions in the right forums, but here's my thinking for suspension.. Check me on my thinking.

- I'm gutting the SH&$ out of it. I've probably pulled 500lb out of it so far (all glass except windshield, all interior, dash, heat, cooling, much wiring, gutted doors, sunroof etc).
- I'm ditching the air suspension. I surfed the various after marked coilover kits and found a wide variety of spring rates. This is not a DTM car, but a Lemon on street tires, so I'm thinking about 700-800lb springs in the front and 450lb in the back, with it lowered as far as possible to keep 2" or so of bump travel.
- Sway bars have to be stock for now
- For now I have to run stock wheels (mine are the 16x7.5") and at least 190 treadwear tires. How fat have folks got tires on these things? I'm thinking 235/50-16? Might run wheel spacers to get a bit more track.
- Anybody have the stock alignment settings? Off the cuff, I'm thinking about -2.5 camber, 0 toe in the front, and -2.0 camber and stock toe in the rear. I'll probably corner weight it too. I really can't go more on camber since tire wear will be an issue (this is a 24hr race, and I don't plan to change tires over the course of the event). I know this suspension is better than struts, so maybe I can get away with less camber?

 

[spf_lexus]

you can squeeze 10x5'' rims if you get a conservative offset. a 44 offset will tuck the back tires in and still clear. For your app I would go staggard 8.5'' front and 9.5'' rear. If your just looking for max size run a 255/35 in front and 265-275/30 in the rear. The suspension/alignment setup is pretty forgiving and allows some serious camber if needed. I bored my alignment slots wider to accomodate more camber correction.

As for gutting the biggest wight savings are the seats at 75lb each and the sunroof which is over 100lb of weight at the top of the vehicle. I thought about ripping mine out too and welding sheetmetal over it but could not give up the moonroof. I bet you could do better than 500lb if your going all out... I can see 750lb+ if your taking the glass out too. Get the battery moved to the tunk also. A/C pump weighs almost 45lb alone and over 50lb with the fans and condensor. Coilovers for early LS fit all LS400 models up to 2000. I have a 1997 rear end on mine, it's all the same. Lextreme has cnversion coilovers for your air ride if your looking for a cheap swap. $750 I think?


Good luck bro. I absolutely love the LS400, had mine 5 years and never want to replace it. So is this just a total budget build? Whats the car looking at racing wise?

 

[Spinnetti]

you can squeeze 10x5'' rims if you get a conservative offset. a 44 offset will tuck the back tires in and still clear. For your app I would go staggard 8.5'' front and 9.5'' rear. If your just looking for max size run a 255/35 in front and 265-275/30 in the rear. The suspension/alignment setup is pretty forgiving and allows some serious camber if needed. I bored my alignment slots wider to accomodate more camber correction.

As for gutting the biggest wight savings are the seats at 75lb each and the sunroof which is over 100lb of weight at the top of the vehicle. I thought about ripping mine out too and welding sheetmetal over it but could not give up the moonroof. I bet you could do better than 500lb if your going all out... I can see 750lb+ if your taking the glass out too. Get the battery moved to the tunk also. A/C pump weighs almost 45lb alone and over 50lb with the fans and condensor. Coilovers for early LS fit all LS400 models up to 2000. I have a 1997 rear end on mine, it's all the same. Lextreme has cnversion coilovers for your air ride if your looking for a cheap swap. $750 I think?


Good luck bro. I absolutely love the LS400, had mine 5 years and never want to replace it. So is this just a total budget build? Whats the car looking at racing wise?

Thanks for the input.. This is my 2nd one. My first one was a 90 that I bought only a couple years old, and drove it until a wicked head-on. This one is pure race car, so no concern for "style". I've already gutted all the stuff you mention, and need to go more. I'm even thinking of sawzall-ing out the entire trunk area behind the rear wheel housings. I'm chipping up the mastic on the interior, and once the cage is in, I might gut the doors down to just the outer skins and weld them to the body. For this race - "The 24 hours of Lemons", the TOTAL build cost has to be <$500 including the cost of the car, but does not include, wheels, tires, brakes and safety equipment, so $750 struts are out! I can sell parts of it which can go into the budget, but haven't put too much effort in that as I just want the junk gone. I got some ebay coilover kit which (last time I got these junk ones) they had 700lb springs, so that should work for the front (I may cut down the stock springs and run both in the front). Somebody at work said they'd spiff me some 500lb for the back which should be close. For starters (until I prove out the concept), I'm going to run the stock 16x7.5" wheels, which is why I'm wondering how wide a tire they will usefully take. On the battery, its best for performance (except drag racing) to keep it within the wheelbase, as close to vehicle centerline and as low as possible. I'm going to put it on the passenger rear seat foot well next to the tunnel. If I put it in the trunk, it becomes a big pendulum that I could do without Next trick is I need CHEAP stock struts as I have the air suspension that is coming out. Speaking of which, is there an online repair manual somewhere? I need to see what all the air suspension components are and where so I can remove all that.

I did some of the gutting at work, and here's how it looked when I brought it home with the trusty tow beast/wife's car:

This is my fresh air mod, that allows cooler outside air to go right to the air intake (I blocked off the stock hole and threw out the snorkel)

This is what the interior looks like right now. I took apart the drivers seat (only 75 lbs? Felt like a lot more), and gutted out the powered base, which I'll attach to my race seat for humor value and to allow for easy driver swaps (will probably run 5 drivers for the event).

 

[Thermactor]

Is this the LS400 that blew its head gasket at the event, and the Audi guys took an hour to get the starter off as a penalty for doing something wrong?

 

[spf_lexus]

hey Spinetti,

Try using dry ice for prying up the old sound deadening. My friend did this on his nissan and it worked like a charm. Get the panels dead cold (leave ice for a while and come back). All I did was smack the panels with a rubber mallet and they started breaking apart and lifting up.


How's the progress? hit 3000LB yet? hehe

 

[driftfx1]

check out my thread i drift mine.. and get toyota to sponsor me naaaaaaaaaaaaaaaw

 

[spf_lexus]

I checked out your vids, looks like you got a nice LS project. Im guessing you picked up that 91 for cheap right? Im sitting in a similar seat with my daily LS. I got it for under a grand and it's just for the daily grind. It came with a 1" rear sway bar, strut bar, boxed arms and a close ratio SC400 auto trans. Not the best setup for drift/autocross like my other one is but still holds a turn fairly well.


Does Houston have a lot of local tracks?

 

[Spinnetti]

Updates....

I got it all done except for the cage. 800lb springs on some honda/neon/something coilovers all around on stock struts from the junkyard. It goes and corners pretty well, but feels DOG SLOW compared to my Audi daily driver.. maybe it will feel faster on track. I wish I had a stick in it! Thanks for the dry ice idea. I have heard of that before, but never tried it.. I just chipped it up. Wasn't too difficult.

Hopefully this link will work: http://www.facebook.com/album.php?aid=102044&id=645133029&l=c51eb4fec1

This is NOT the lemons lexus that puked... I'm reasonably confident in this one. Hopefully it will hang together. I'm planning to do a track day with it soon to wring it out and see if its race worthy before I put the cage in.

 

[driftfx1]

I checked out your vids, looks like you got a nice LS project. Im guessing you picked up that 91 for cheap right? Im sitting in a similar seat with my daily LS. I got it for under a grand and it's just for the daily grind. It came with a 1" rear sway bar, strut bar, boxed arms and a close ratio SC400 auto trans. Not the best setup for drift/autocross like my other one is but still holds a turn fairly well.


Does Houston have a lot of local tracks?

theres a couple around here. but im all drift

 

[Thermactor]

LS4 Racer

Updates....

I got it all done except for the cage. 800lb springs on some honda/neon/something coilovers all around on stock struts from the junkyard. It goes and corners pretty well, but feels DOG SLOW compared to my Audi daily driver.. maybe it will feel faster on track. I wish I had a stick in it! Thanks for the dry ice idea. I have heard of that before, but never tried it.. I just chipped it up. Wasn't too difficult.

Hopefully this link will work: http://www.facebook.com/album.php?aid=102044&id=645133029&l=c51eb4fec1

This is NOT the lemons lexus that puked... I'm reasonably confident in this one. Hopefully it will hang together. I'm planning to do a track day with it soon to wring it out and see if its race worthy before I put the cage in.

Great post, and great pictures. Thanks heaps (to borrow a term from Australians) for posting up the link and the information!!

I'm in Northern KY right now - I don't know where in KY you are, but if you ever need a helping hand or just want to shoot the breeze about these cars, let me know, I've got nothing but time on my hands!

 

[Spinnetti]

Great post, and great pictures. Thanks heaps (to borrow a term from Australians) for posting up the link and the information!!

I'm in Northern KY right now - I don't know where in KY you are, but if you ever need a helping hand or just want to shoot the breeze about these cars, let me know, I've got nothing but time on my hands!

No kidding? I work in Erlanger.... at, erm... Toyota's HQ

You know anything about trans mods? Any skilz on troubleshooting wikkid driveline vibration?

 

[Thermactor]

No kidding? I work in Erlanger.... at, erm... Toyota's HQ

You know anything about trans mods? Any skilz on troubleshooting wikkid driveline vibration?

That's cool, I live about 5 miles from there. Bad driveline vibration could come from any number of things, but I've heard of and seen a good number of potential fixes. As far as the trans goes, I know of one easy trick and another trick that's not as easy, but still doable and next to free.

 

[Spinnetti]

That's cool, I live about 5 miles from there. Bad driveline vibration could come from any number of things, but I've heard of and seen a good number of potential fixes. As far as the trans goes, I know of one easy trick and another trick that's not as easy, but still doable and next to free.

PS, vibration was just low fluid oddly enough. Getting the cage in next month and racing in Michigan in April (finally)..

What was your tranny fix? I'd like it to shift harder, but adjusting the cable doesn't seem to do much?

 

[brawls43]

Nice looking car, how did it run in Michigan? I run a 92 SC400 in Chumpcar. Gotta love the 4.0L V8! Did you do the upgraded 95+ brakes? We did, and absolutely love them. We can outbrake almost anyone. My blog has info on our build and our races from last year and this year.

teambearpatrol.blogspot.com

 

[Spinnetti]

Nice looking car, how did it run in Michigan? I run a 92 SC400 in Chumpcar. Gotta love the 4.0L V8! Did you do the upgraded 95+ brakes? We did, and absolutely love them. We can outbrake almost anyone. My blog has info on our build and our races from last year and this year.

teambearpatrol.blogspot.com

Only driver mistakes kept us out of the hunt... about 4th fastest lap I think, great under braking, handling was very neutral. Auto trans blows, but I'm doing some tweaks... Got a 4.27 diff cheap from the junk yard, and will be modding the car to put that in.. will help a bunch.

 

[brawls43]

Did you do any sway bar work? Like custom adjustable endlinks or anything?

 

[Spinnetti]

Did you do any sway bar work? Like custom adjustable endlinks or anything?

Yeah, but that's pretty easy depending on the sway bar config. Couple rod ends and threaded rod is about all you need. End links aren't a huge issue that needs solving though. In fact, I think the factory bars are adequate.

 

[brawls43]

They seem little, but it they're adequate, its one less thing to mess with.

 

[Spinnetti]

Weighed it today (corner weighted it actually)... Its 3175 w/o driver with a full fuel load.. not bad... can probably get another 150 out of it with race wheels and some more sawzall work...

 

[Spinnetti]

Just thought I'd do a quick update... I keep tweaking the car, but we are typically one of the fastest cars at every race. Fuel consumption kills us, but its worth it to go so fast I'd like to swap a 98-00 driveline in to improve economy. I can get them cheap locally - how hard is it to do? Other than that, its really "done" and working fantastic.