When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Great, you're on track for a nice, reliable 400+ hp at this rate. You're really going to enjoy it. I suspect you're going to want an LSD though, because the open diff is pretty wack when you start applying a good amount of power through it, especially with the GS300's gear ratio.
I know my setup as a whole is good for 500hp, but I’ve read everywhere that the trans can’t take over 320-330whp. So I was really only planning to run it at the 8 psi wastegate spring. I have a MBC to go slightly higher if needed to reach that goal.
What are your thoughts on the transmission’s ability to hold power? If 400 is safe and the engine can take it with proper tuning/timing etc. then of course I’d like to go more. I’m not exactly in the position to do this build
and pull my transmission out too at the moment to try and strengthen it.
I think I’ll be pretty happy with 320ish whp and know that none of my components are being stressed very hard at all. That’s still a decently fun amount of power for street use. Will certainly surprise a lot of people. Can always go more in the future.
JeffTsai (who is no longer an active user) is running 1000+ HP to the wheels through the factory A650 transmission with some mods to handle the power on his GS300. I think you're right about the 325 HP with no modifications though. He started PowerDynamix in Texas so I'm sure he could upgrade the factory trans if you're interested
I had planned to dyno the car in it's current N/A setup. But unlike other cars I've built, the tuner near me that's willing to tune/dyno the car wants $850 for the day tuning it. So I won't be able to dyno it just to see the N/A power from the cams and bolt on's. However CX-Racing rates the kit I'm using at 260-280whp on the 8lb waste-gate. I believe the car is going to easily make 300+whp with the cams since they compliment forced induction nicely. I am hoping not to have to turn up the boost to reach 320ish whp. This will keep the eng/trans safer for the time being. Without the cams I'd probably have to push 10 or more psi and put more wear/possible damage on the engine to reach my goal.
I started out with wanting to just do a mild N/A build, which turned into a mild NA-T build, which I'm sure is quickly going to become a medium-higher power build in the future. My setup and fuel system is ready to push 500+whp with a thicker head-gasket, arp studs, and a stronger transmission. I still plan to get an LSD in the rear end and eventually strengthen the transmission. Once that happens, I'll pull the head, refresh it, and do some of my own porting, and go back together with a thicker HG/ARP studs, then turn up the boost! I see that being a good year or two down the line though. Maybe around the time I have to tear down and pass smog.
Anyways, the current task at hand is to get this build done right. There is potential for future growth. But right now is a safe 300+whp level and everything functioning good for daily drivability. I'll try to get pics of the process. I still have other things I'll be doing to perfect the setup. I want to work in an oil catch can setup, and an oil cooler for example. Still want to customize my ashtray for the AFC Neo to fit into nicely. Several projects yet to come.
Last edited by TrueGS300; Aug 9, 2019 at 06:33 AM.
I have some good news/info for NA-T swap basics on the 2gs. Not that it was easy, but there are a few things that have to be done, all are pretty simple and free.
1: Drilling the oil pan for the oil return line. This had me worried because all you can ever find is Supra builds etc doing this and the pan must be removed to do it right and not end up with aluminum shavings in the engine. It calls for 12 hours on AllData. But the GS has a front sump lower pan, not in the rear like other 2j’s! By removing it I could easily drill the pan and install the return line fitting with all shavings dropping right out and easy to clean. I also found a better spot to put the fitting. There is a flat spot next to the original port template. Makes for a way easier instal.
2: 180* turn of the thermostat housing. The original placement of the thermostat housing angles back towards the exhaust and runs the lower radiator hose to close to a turbo/manifold. But it can be installed the other way and point down and out of the way instead. Just make sure you orientate the thermostat inside so the hole is up. Baicaly turn the thermostat in the housing 180* and the install the housing 180*. I didn’t get a pic of this because it’s self explanatory.
3: Shorten this heater hose. When I was mocking up the setup. For whatever reason the original shape had this line running way out and looping around much to close to the manifold. I got rid of 2/3rds of it and was able to keep the part that actually has the preshaped bends you need. Clears the manifold by far now.
Last edited by TrueGS300; Aug 12, 2019 at 03:35 AM.
I’ve had this thing running a couple days now. No tuning or injector upgrade installed yet. Mostly braking it in and checking things over. Install went well. Car feels great and pulls hard. Not going crazy with it of course. But the wide band shows it isn’t leaning out or anything. Anyways here’s a few pics of the completed project.
I’ve had this thing running a couple days now. No tuning or injector upgrade installed yet. Mostly braking it in and checking things over. Install went well. Car feels great and pulls hard. Not going crazy with it of course. But the wide band shows it isn’t leaning out or anything. Anyways here’s a few pics of the completed project.
way to grab the bull by the horns. listen man, dont waste your money on some tuner guy wanting to charge you 800 plus for a day of tuning. the safc neo is sooooo simple. its almost insulting that guy wants to spend all day fiddling with some plus or minus numbers. now that you have a wideband in the car you can easily do it yourself. you have no control over tuning so all your doing is getting your afr's correct. and since your running some 550s now youll be pulling fuel from the start. you will need a scan tool that reads fuel trims. you will need to start with pulling atleast 20 percent across the board. than look at the short and long term fuel trims and keep pulling or adding fuel on the safc until your fuel trims get close to zero. and do not expect immediate changes. the stock ecu is going to be freaking out so take your time and make small changes. also, dont forget, your stock engine is high compression so its going to want to knock if you go lean. i hope you installed some atleast one step colder spark plugs.
way to grab the bull by the horns. listen man, dont waste your money on some tuner guy wanting to charge you 800 plus for a day of tuning. the safc neo is sooooo simple. its almost insulting that guy wants to spend all day fiddling with some plus or minus numbers. now that you have a wideband in the car you can easily do it yourself. you have no control over tuning so all your doing is getting your afr's correct. and since your running some 550s now youll be pulling fuel from the start. you will need a scan tool that reads fuel trims. you will need to start with pulling atleast 20 percent across the board. than look at the short and long term fuel trims and keep pulling or adding fuel on the safc until your fuel trims get close to zero. and do not expect immediate changes. the stock ecu is going to be freaking out so take your time and make small changes. also, dont forget, your stock engine is high compression so its going to want to knock if you go lean. i hope you installed some atleast one step colder spark plugs.
Thank you, the more I've thought about it the more I've been wanting to dial it in myself. I was actually thinking of getting AEM's data logger because my AEM wide-band is the UEGO unit that wires into the data logger. Then I can see all information on my computer (air fuel ratios at all rpm increments) and make all the adjustments all at once to the air map in the Neo. And just do that until I see good numbers at all times on my wideband. But I do have my Snapon Modis scanner too. I don't know how hard it would be do do tuning with that. Watching data and trying to adjust the Neo while driving.
To be honest the car is doing outstanding already. I haven't really got on it hard, but when I get it to about 5psi the ratio goes rich to about 12.5:1 it seems to be a little lean idling and cruising 15-16. But it responds very well to the boost and doesn't seem to be running out of fuel or anything. I'll move to a colder plug when I go after the injectors. Have a number for them?
Hey before I order new plugs, should I be going 1 step colder or 2? Right now I'm running NGK iridiums with the normal 5 heat range. Am I good to just go to 6? I went to 7 in an older Eclipse 4G63T build, but it was pushing a lot more boost.
Also would this be the right plug? BKR6EIX-11
Last edited by TrueGS300; Aug 22, 2019 at 06:30 AM.
A *qualified* tuner with a dyno will do a much better job that any Joe Blow doing it for the first time can. Period. It's not debatable. You're not just paying for the use of the shop, or their time, you're paying for their knowledge and experience. Kindly sod off with this anti-expertise stance. You can't street tune a car as well as a tuner with a dyno.
Yes, you can DIY a lot and be perfectly successful. Nothing wrong with that. Experts with the correct tools and experience are always going to do a better job, that's why it's their job.
