Supercharged GS400 tuning/ performance questions
got another ?. has anyone changed out the internals/ fuel pump etc to handle more boost? how much time and $$ does that iinvolve, also if my tranny is shot I will go six speed (hopefully jpi would do it, the guy was pretty adimant about not wanting to tune my safce) how much time / money will that take? the money isn't the prob (I'm working out a deal to sell my old gs for pretty much what I paid for the new one.
Last edited by gs400 civi; Jun 18, 2009 at 08:29 AM.
WOW the 426 will be worse. if the 3.76 is giving trouble the 4.26 will spool up so fast you wont need 1st gear.
Most go w/ the intank 255 Whalbo fuel pump for added fuel I don't think you need it if you staying around 340-350whp but some get it for anyway.
Tuning the SFAC-Alot of tuners perfer to use something that has more variables to control and manage the fuel, timing,boost,A/F etc it is just safer Jason has done Sfac tunes but if your asking someone to push the hi whp #'s they want tobe able guarantee it won't blow up.
With that said there have plenty of SFAC tuned fi GS400's but I don't think many pushing the 380ish rwhp some correct me if I'm wrong. Morris comes to mind, he gotinsane #'s from his RMM/SFAC tune.
It depends on what your comfortable with
Most go w/ the intank 255 Whalbo fuel pump for added fuel I don't think you need it if you staying around 340-350whp but some get it for anyway.
Tuning the SFAC-Alot of tuners perfer to use something that has more variables to control and manage the fuel, timing,boost,A/F etc it is just safer Jason has done Sfac tunes but if your asking someone to push the hi whp #'s they want tobe able guarantee it won't blow up.
With that said there have plenty of SFAC tuned fi GS400's but I don't think many pushing the 380ish rwhp some correct me if I'm wrong. Morris comes to mind, he gotinsane #'s from his RMM/SFAC tune.
It depends on what your comfortable with
I personally don't care for the SAFC too much, if they want me to get something better/ different I don't care, I'll probably go figure it out w/ jefftsai anyway so I can at least learn something/ move closer to being able to mess w/ it myself.
on the gearing, doesn't the gs3 have 3.93 gearing, what do the high boost gs3 guys do?
on the gearing, doesn't the gs3 have 3.93 gearing, what do the high boost gs3 guys do?
Last edited by gs400 civi; Jun 18, 2009 at 12:44 PM.
Joined: May 2001
Posts: 8,702
Likes: 5
From: California
I had a fun time swapping out the stock pump for the Walbro using the factory assembly. Instructions would of helped. It wasn't hard, I'm just saying it's not a simple DIY for someone who's not mechanically inclined.
Joined: May 2001
Posts: 8,702
Likes: 5
From: California
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?
Did you get the ATS Carbonetics thats for the Supra? is it a direct bolt into the stock diff. case?
305's are next on my list now that Michelin FINALLY came out with that size in 20". I've only been waiting for the release for 3+ years
It's a direct bolt on just like the TRD unit.
http://www.carbonetic.net/products/carbonlsd.html
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From: California
I could of polished the cover, but I know it will be difficult to keep clean.
I wanted to try out this new PVD process offered by www.SIKIndustries.com. It's not chrome plating, but it has the durability and shine of chrome. It's not chemical dipped and it's not chrome colored paint.
The PVD process or Physical Vapor Deposition, can be used on non-porous materials like plastic to provide a chrome like finish without the chemical dipping. What would be difficult with chroming the differential cover is trying to get a smooth shiny finish inside all the nooks and crannies.
Here's what the cover looked like before I had it done.
I wanted to try out this new PVD process offered by www.SIKIndustries.com. It's not chrome plating, but it has the durability and shine of chrome. It's not chemical dipped and it's not chrome colored paint.
The PVD process or Physical Vapor Deposition, can be used on non-porous materials like plastic to provide a chrome like finish without the chemical dipping. What would be difficult with chroming the differential cover is trying to get a smooth shiny finish inside all the nooks and crannies.
Here's what the cover looked like before I had it done.
I've got the 2.83 pulley. My tuner said I was not much over 6lbs, but I'll need to hook up a wideband to verify. 370 injectors and a "conservative" tune.
305's are next on my list now that Michelin FINALLY came out with that size in 20". I've only been waiting for the release for 3+ years
It's a direct bolt on just like the TRD unit.
http://www.carbonetic.net/products/carbonlsd.html
305's are next on my list now that Michelin FINALLY came out with that size in 20". I've only been waiting for the release for 3+ years
It's a direct bolt on just like the TRD unit.
http://www.carbonetic.net/products/carbonlsd.html
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.
Also I measured both pulleys and they are 3 1/4" and 3 1/2" respectively i believe the right one is smaller.
If you want over 400hp build the engine, figure out your fuel and timing management and have a plan for a tranny that will hold up as the stock one wont.
I hope this helps, not trying to dissuade you but want you to go into this with your eyes wide open. I would hate for anyone to have to learn like I did via trial and error.
oh not dissuaded at all, I have a plan for the tranny and management (jefftsai got me covered), he has a wideband and guage, I will probably go AEM for more/ better control. As far as the tranny he can getparts/ build mine, I'm just trying to find all the internals/ I need a breakdown of what I need to do/ the cost. Any thoughts?