gs400 civi

iTrader: (4)

hey I've just got a hold of a supercharged gs400, and I need somewhere to have it tune in the tx/ west tx area.its currently using an SAFC for A/F control I also have some questions

so far it has the supercharger, 3.76 lsd, 3" exhuast from the cat back, w/ the last resonator deleted.

I want to get the S&S headers but my question is does anyone/ can you do anything about the cat area between the two? that seems like it would be the bottlneck in the exhuast system.

I'm also interested in a higher stall torque convert 2800 or 3000?.

another thing I was wondering about is that a turb can spoolup at say 3000rpm's and hold that pressure to redline but a sc setup only make max boost at wot, can you use a different pully setup on an sc that will have the sc spin to full boost at 300 then us a blowoff valve or some kind of valve to let off the extra pressure so you could have full boost at a lower rpm and hold it from 3000 to wot?


the last thing is the intercooler, I want to replace it cause I hit a rabit on the way home and it dented it, can/ should I go larger? where to buy?

Can someone help w/ these questions? please

gs400 civi

iTrader: (4)

14 views and nothing? come on people, how bout a finder's fee for the info? I really need this tuned I don't know if its running lean/ rich and i don't think the SAFC will tell me that.

vwynn

iTrader: (4)

i dont think anyone would comment if you complain that no one is responding... just give it time.

if bottle necking is an issue, redo the exhaust system.. X pipe the second cat, and delete resonaotor.

the SC is centrifugal (SP) so its normal to build pressure as the RPM increases... since its going off the drive belt unlike an actual turbo setup.

the intercooler was specically chosen for the SC kit.. if you want something else i believe you would have to redo the piping which can be a PITA.

gs400 civi

iTrader: (4)

thanks for the response, sorry for sounding impatient but I'm not trying to have it brake. the reason I want to change the intercooler is that mine is dented/ bent from a rabbit

speedaddic

iTrader: (10)

you can buy a core intercooler and have end tanks welded on to fit the application. I'd run an x pipe for the exhaust. I got mine from Summit Racing. Get yourself a wideband, you'll need it for tuning. Tuning the AFC shouldn't be a big deal with the wideband. You want to stay around 11.0-11.5 while in boost. Definately get the headers. I gained 17whp from the headers alone.

RMMGS4

iTrader: (5)

I already have the S & S headers, x-pipe, and resonator delete. Your SC needs to breath and these things will all make a noteable difference.

If you note in the classifieds I am selling the above set up because I am going to 2.5 inch piping from the cat back, new larger x-pipe, mufflers that have more flow and also eliminate some of the un-neccessary piping bends that the stock set up has. The new exhaust will also be mandrel bent and no bemd angle sharper than 45 degrees.

So you see I'm trying to get every last drop out of the exhaust set up.

RMMGS4

iTrader: (5)

If the intercooler is not leaking, you might wanna live with it. That was a custom intercooler designed to fit behind the stock front bumper, so it has a ton of custom bent piping in order to allow it to clear the bumper in such a cramped area. Getting an exact replacement is going to cost $$$. You won't find an equivalent generic replacement "of the same size" AND "One that will fit in the current space" on E-bay.


The other nasty part is on the exit side of the intercooler the pipe has to bend a very tight 180 degrees back the other way(This is not a standard 180 pipe bend, I'm talking a tight 180 turn in maybe a 5 inch radius). Most intercoolers are symmetrical in their entry and exit which is a smoother path for the air to flow.

You won't be able to go bigger without re-locating the intercooler downwards from the existing location. If you have a bodykit with ample room you can do this. The lower and more forward the front of the kit is the better.

What a coincedence that I am also in the process of adding a bigger intercooler to my set up and a complete re-do of the piping with all the nasty bends removed.

I'll have to post pics some time soon.

GILLEXUS

iTrader: (14)

Post pic of what you have.bigger intercooler? depends on what you have. Most of the ones I've seen on the RMM S/C kits are a decent size unless the person you got it from put something on totally different.

Tuning your SC- I'm not sure how close or far from Garland but Jason at JPI racing I've heard is pretty good and he knows the Lexus motor. I know he's done the RMM SC on a few members. He did ciscorusty's and his ran off a SFAC-II-


https://www.clublexus.com/forums/per...s400-done.html
https://www.clublexus.com/forums/lex...dallas-tx.html



Higher stall TQ-I would say wait until you get your S/C on. A few People have had problems w/ the 3.73 rear and 2800 stall TQ it would bounce off the rev limiter and not shift as quick . Definitely I would be cautious w/ the 3000 stall & 3.73 rear. what some have done is go w/ 2600 stall or use the TRD LSD ( stock gearing) / 2800 stall. And some have had no issues.

CATs- do a search there have been a few that have custom exhaust deleting the cats. Jbrady says that the stock cats are pretty low restrictive.


Earlier boost spool-up I found this for superchargers "Adjustable Boost Limiter Valve " sounds interresting I don't know of any one using it-

http://www.928motorsports.com/parts/...mitervalve.php

Just my $.02

gs400 civi

iTrader: (4)

first off thanks for the response everyone, its much appreciated. I would like a larger intercooler, and I have a kit on the way that I bought from Karizma on here. what I've been wondering about the piping etc is why didn't they find a way to get it on the other side instead of bending it back 180? is that possible.

I also found out that my CEL code p0770 was the first gear shift solenoid and I haven't had first, I'm going to the stealership tomorrow to see what all can/ will be done about that.

RMMGS4

iTrader: (5)

Your advice is def worth more than $.02

I'm pretty much at 400wHP and I think those with say under 350 will probably like the 3.73 gear, but in my case I'm revving up too quickly, plus off the line I can just melt down my 295/20's, so I recently changed back to stock gearing. Secondly the Supra TT and TRD LSD are just not going to work for me as they are not working well when trying to accelerate hard coming out of a turn, so I switched to an ATS Carbonetics 1.5 way LSD. I'm now able to get on the power earlier without kicking the back end out.

RMMGS4

iTrader: (5)

The kit was designed around 2000 and there is some interference preventing the piping from going around the "standard" way. It is possible to modify a pre-2001 model to allow the piping to go around, but Rod Millen sold this kit as a TRUE bolt on affair into a stock front end, so I assume that's why they did it.

I looked at a 2001- up GS, and they changed the location of some things so from what I can tell there might be enough clearance to run the piping, with no mods.

I think this clearance issue is only on the V8 as I see the inline 6 appears to clear.

I am currently changing my set up to have a larger intercooler moved forward and lower, plus I made other changes to make enough clearance to run the piping around symetrically.

JeffTsai

iTrader: (1)

I know I'm far from you, but you did come to me last time to work on your car. I can fabricate the custom piping for you and tune the car as well. You will need to get a wideband and boost gauges at the bare minimum.

gs400 civi

iTrader: (4)

tell me when jeff!!!, as soon as I get this shift solenoid issue resolved (hopefully before the end of this week) I will come up there, perhaps as soon as this weekend if that's good forr you, I'll pm you.

GILLEXUS

iTrader: (14)

Thanks, Yea 400whp is sweet not many have that worry (a nice worry to have) How many psi you pushing, Did you go w/ the larger than 310 injectors? I would think those 295's would help look like it time for some 305+ squeezed in there
Did you get the ATS Carbonetics thats for the Supra? is it a direct bolt into the stock diff. case?

gs400 civi

iTrader: (4)

It has 550cc injectors(thank you god!) I have the supra tt lsd with the 3.73 or 3.76 gearing whatever it is. If it causes issues witha 2800 or 3000 stall TC then I will put the 4.26 gears out of my old gs4 pumpkin.

Also I measured both pulleys and they are 3 1/4" and 3 1/2" respectively i believe the right one is smaller.