GreenBeast

I was looking around and found everyone has some issues with the OBX headers for the SC3 and I was wondering if anyone knows if IS300 or Supra MK4 NA headers would fit on the SC3s. I saw that the problem on the OBX headers was the downpipe and a bung for the second manifold O2 sensor and I'd rather have a direct bolt in system that won't cause any headaches plus the NA MK4 headers are cheaper. Any insight on this would be nice. Thanks!

scsexy

iTrader: (1)

Don't waste your time with headers and go Na-t

GreenBeast

I will not go NA-T I have other plans for the car. Going NA-T is a very bad option right now because I don't necessarily have thousands of dollars and countless hours to throw away. I want to have a solid system for right now then in maybe 3ish years I will park it and really dig in.

mikef

iTrader: (3)

then dont even waste your money on headers, and wait in 3 years, its worth the wait,

GreenBeast

Well my headers have leaks and the OEM headers suck so if I'm going to have to replace them for the same money I can buy nice high flow headers and I was asking a question about fitment not how I need to go about doing things on my car.

KahnBB6

iTrader: (5)

It's really not worth it for the money the headers will cost you. And yes some people have had issues if their header did not allow for two O2 sensors to be installed in the header. I believe two certain model Bosch screw-in type O2 sensors are required.

If you have a damaged or cracked factory exhaust manifold just find a used one. They almost never have those issues and they are extremely plentiful and cheap. No need to buy a brand new one from the dealer.

To keep a 2JZ-GE in NA factory tune the stock cast header is fine. The OBX/MVP header looks nice but it will lose you some low end torque while giving you a whopping 10hp or less. These engines in NA form are not like Honda engines (or similar) in NA form.

By spending $15,000+++ some few people worldwide have made some power with NA 2JZ engines by completely working over everything and using mandrel bent custom headers, ITBs, aftermarket engine management, upgraded fuel system, etc.

But people going NA-T (or GTE) for a few thousand have made the same power and much more.

The JZ engines really respond best to turbocharging no matter how you go about it so long as you have a good engine computer setup. If boost in any form isn't in the cards for you right now I'd recommend holding off until such time that that option becomes something you can move on.

The IS300 header probably won't fit because it's for a different chassis. The Supra MKIV 2JZ-GE NA header will be exactly the same thing as the SC300 2JZ-GE header. Toyota may even stock a different part number but I guarantee you that year-for-year they will be identical since both the MKIV and SC are 95% the same chassis underneath and their non-turbo engines are set up exactly the same way in both cars other than the wiring harnesses.

There are no inexpensive high flow modifications that really amount to much with these engines. It all comes back to turbocharging which these 1992-1997 engines (unlike most other common car engines) were over built strength-wise to handle from the factory even if they were set up in non-turbo tune off the showroom floor.

In NA form the best bang for the buck power to the ground improvements are good stock engine maintenance, a manual transmission swap, a 4.272:1 rear end ratio if you don't have one already (all automatic SC300's do) and suspension, braking and wheel/tire improvements and an LSD.

Getting more horsepower is actually cheapest with an NA-T setup or extremely basic 1JZ-GTE swap.

Kayasith95

iTrader: (4)

Back in the day i contemplated getting headers also and people told me the same thing (Go na-t). Then my exhaust leak got worse and no money so i bought some 2.5" obx header and midpipe from ebay that say fit a supra to replace the crap. Bought two screw type o2 sensors and had to relocate the rear o2 bung but it works. There is some interference between the flange from the header to the midpipe and the subframe. The whole thing was a tad shorter than the sc300 oem exhaust so i had to stretch it a bit. In total it all costed about $300 or so but theres also no catalytic converter. NOW theres actually replacement headers with catalytic converters for around the same price on amazon.

scsexy

iTrader: (1)

I got na-t done for 2000 dollars and i was a novice just learning to wrench and for sure spent more than i needed on a kit compared to piecing it together. car always started but sometimes died after boosting and coming to a stop. Was my auto i have a thread on it.

Just get a set of used ones for 100 bucks and save your cash. Why deal with interference, and pay more money for less performance? You really need to consider the amount of money lexus put into research for their stock headers. They perform the best over all the rpms. Aftermarket ones usually are very very slightly better at WOT and over say 5500 rpms, at the cost of down low performance or vice versa.(NA) supercharged might want more flow and well turbo obviously have to be different for the turbo lol


I'm in the processing of getting my manual car set up NA-T jdm supra ecu is300 coils.

Kayasith95

iTrader: (4)

for the time being it was quick and easy so i bought them. There were no salvage yards with them because they always hack them off due to the catalytic converter being a part of the manifold and they always cut it wrong. but that was about 2 years ago and i was in college using it as my daily. But now since i got a second car i just finished dropping in a 1jz vvti for around $2500.

Studiogeek

iTrader: (6)

I read that problem was super common with NA/T that kept the stock ECU and MAF. The TT ECU Mod would have resulted in a rock solid, inexpensive system.

For the OP.....
I don't think the aftermarket stuff at OBX level last nearly as long as the stock stuff. To be honest, every performance mod I made to the car the first year i had it was a waste of money. All that stuff got ripped out when I boosted the car. Its a 2J....... you'r going to boost it. Save your bread man. I wasted thousands.......

Sorry to pile on AND not answer your actual question but we don't want to see you waste your bread.

scsexy

iTrader: (1)

That's what im doing with the manual car =)

GreenBeast

Well I just changed the oil today and found metal shavings so guess who's going to be saving for a GTE swap. I just need to figure out how to change a front sump to a rear sump.

Studiogeek

iTrader: (6)

Condolences AND Congratulations!

mikef

iTrader: (3)

Just get a supra swap they are rear sump

scsexy

iTrader: (1)

Damn dude i wonder what happened to it... Think about a 1jz if your on a budget