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Hello I just bought a 1990 turbo Supra and I was wondering what parts do I need to get it up to 500whp I have 6 thousands dollars to spend on upgrades. Thank you for your help

Ps. It’s stock
 

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First you have to make sure your 7M (if that's what you have) is healthy and has a MLS headgasket torqued down properly.

Way back I made 511rwhp with a PT61mm turbo/HKS manifold/40mm waste gate, full exhaust, front mount intercooler and pipes/BOV. Stock ECU/lex AFM/AFC, 550cc injectors/walbro pump. HPF clutch. That was with a stock head, stock cams, stock short block. 25psi on 116 octane.. You should easily be able to make 500+ for under $6K with all the ebay stuff out nowadays.
 

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my advise would be to go to the dyno thread on this site and look at people who have made similar power. a lot of cars on that thread have really good write ups / build threads that you can dig deeper into


like others said step one is figure out the turbo (size/characteristics) you are looking for

next is fuel system. 500 hp is really right at the break point, you can piggy back it there (aka the larger lex afm housing + safc piggy back) or you can go stand alone. each has its pros and cons. one is cheep, the other is (better) and more expensive.

also you have to choose fuel. an e85 build making 500 whp is different than a 116 octane build. or better put, decisions can be made to optimize the fuel you chose. side note, your not going to use e85 on the stock ecu though so that choice means stand alone fuel.

then you have the clutch decision. super heavy 500 whp+ cutch that has potential to walk the crank or expensive dual disk that is noisy. if your careful and always start the car in neutral (without depressing clutch) 500hp single disk clutches seem to work great right up to 500whp or so (again, check what others run and post about)

good car, good budget. if you do most of this build yourself thats a lot of parts to buy.

think this through / plan each step and you will have a nice fast supra when your done.
 

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I'd spend the money on head studs, a good ecu, a good turbo, and a mild intercooler. Upgrade the intercooler later if you have heatsoak problems. Maybe consider skipping the big FMIC that people have loved for so long and go to something a bit more modern/efficient like a water to air. The packaging of a system is smaller, although a bit more complicated.

Skip the ebay trash period, the end. If it's a non moving part it might be ok, like a cat back, but expect it to need modifications for a perfect fit. I wouldn't buy an ebay turbo, intercooler, injectors, or anything else really..... because it's all chinese junk that won't last a long time. I know people will take issue with me saying that because they've personally invested in ebay stuff for their car, but I will tell you that this car thing is a pay to play game. Nobody is going fast for very long on cheap ass parts.

Focus on how you will tune your car first. I would probably buy the ecu you want first. Depending on what you do there, you could eat the entire 6k budget on the computer alone ..... but I know you're not going to do that. I'd buy a used aem infinity from someone or something along those lines. Don't bother with the piggy back crap either if you plan to make more power in the future. None of the piggy back solutions are good long term solutions, they will limit your power, and will harm your engine (long term) due to lack of ignition timing control.
 

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Im not sure I agree here that using a piggy back, around 400 whp is dangerous or harming your engine

my maft-pro has held a very consistent tune, afr in boost ~11-11.5

safc + lex afm +550 is also very stable in tune / safe (imho) at that power level too

running 14 psi, 98 octane (pump + a mix of race gas)and a big fmic, I bet I never knock. off boost it runs as it should, 14.7 stoich

I dont see how any of that is hurting my engine any more than just the plain physics of it, slamming boost in there and shifting at redline et. meaning a stand alone would not make it live any longer, if the premise is it (standalone) holds a tune better

with a piggy back its so much easier to tune you can learn to do it yourself. much harder to do that with a standalone. don't get me wrong a stand alone is way better, but 400-500 whp...I dont know if the pros outweigh the cons


its not so much where you buy you parts, its what you buy. you can get name brand (bosch, borg warner, aem, etc) on ebay, they don't just sell junk ;)
 

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I definitely agree with Madison. For 500rwhp the stock ECU works great and is very easy to tune. You can go with a Lexus AFM, a MAFT-pro, or a HKS VPC to name a few. I currently use a VPC with a SAFC and it works great.
 

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My concern with the simple piggybacks and elevated power is the lack in timing control. You're stuck living in the world of the stock ECU and you can only move the tweaked air/fuel flow values. I'm sure it can be done safely for a long time, but there's some added risk that you can mitigate with a full standalone.
 

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My concern with the simple piggybacks and elevated power is the lack in timing control. You're stuck living in the world of the stock ECU and you can only move the tweaked air/fuel flow values. I'm sure it can be done safely for a long time, but there's some added risk that you can mitigate with a full standalone.
I know it's anecdotal, but in my case with a VPC, AFC, and EVC... stock ECU, 720cc inj, and MSD ignition... I was riding around 600hp for 2 or more years. It did eventually break, but I still think it's pretty impressive for what it was. (Stock crank, but crowler rods, JE pistons, HKS mls hg.)
 

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I know it's anecdotal, but in my case with a VPC, AFC, and EVC... stock ECU, 720cc inj, and MSD ignition... I was riding around 600hp for 2 or more years. It did eventually break, but I still think it's pretty impressive for what it was. (Stock crank, but crowler rods, JE pistons, HKS mls hg.)
What broke?
 

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My concern with the simple piggybacks and elevated power is the lack in timing control. You're stuck living in the world of the stock ECU and you can only move the tweaked air/fuel flow values. I'm sure it can be done safely for a long time, but there's some added risk that you can mitigate with a full standalone.
stock ecu has dual knock sensors. stock ecu lives in the world of "someone could put 85 octane in this in the mountains one day, then drive to sea level at 110 degrees out and beat on it the next with shitty fuel"

there are safety margins built into the stock ecu and it has the ability to detect knock and retard timing.

its this feature, along with all the other mods (larger intercooler / injectors , better turbo, higher octane fuel) that makes running 2x the factory hp somewhat sane / reliable on the stock ecu

any way you shake it its apples to oranges so to speak. out of the box, a factory supra will run 6psi at a stupid rich 10:1. talking a total stock car

a tuned car like mine, upgraded turbo pushing 14psi at 11.5 afr is an entirely different animal.

one has cool egt and is prob washing the rings with raw fuel

one has way higher egt and 2x the power

stand alone, piggy backed ecu, whatever, 2x the power and in tune is a different animal VS stock tune and boost levels

if you piggy back setup is legit and in tune I don't see a stand alone adding a layer of safety at only 15 psi
 

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stock ecu has dual knock sensors. stock ecu lives in the world of "someone could put 85 octane in this in the mountains one day, then drive to sea level at 110 degrees out and beat on it the next with shitty fuel"

there are safety margins built into the stock ecu and it has the ability to detect knock and retard timing.

its this feature, along with all the other mods (larger intercooler / injectors , better turbo, higher octane fuel) that makes running 2x the factory hp somewhat sane / reliable on the stock ecu

any way you shake it its apples to oranges so to speak. out of the box, a factory supra will run 6psi at a stupid rich 10:1. talking a total stock car

a tuned car like mine, upgraded turbo pushing 14psi at 11.5 afr is an entirely different animal.

one has cool egt and is prob washing the rings with raw fuel

one has way higher egt and 2x the power

stand alone, piggy backed ecu, whatever, 2x the power and in tune is a different animal VS stock tune and boost levels

if you piggy back setup is legit and in tune I don't see a stand alone adding a layer of safety at only 15 psi
I agree at 15 psi on a CT, but that's not the topic in the thread, is it? 500whp is beyond the limits of a CT and probably 20-25 psi on the turbos most folks would choose, or so I think.

I know the piggyback approach can be safe, but I do think you're on the hairy edge of trouble because of the lack of timing control. The stock ECU has safeguards for the stock map load levels. The piggyback skews those tables and areas of the table that didn't need safeguards at stock levels, definitely should have those safeguards at 2x the power. Problem is, the ECU has no idea you're flowing 2x the amount of air and fuel that it planned on. I know standalone's aren't cheap, but neither is an engine rebuild if you get that tune just a little off.

With the MK3 I think there's a really safe power level that ends around 400-450 whp. Past that, you're in tricky territory where a lot of the simple tuning methods still work if things go as planned, but you're very close to a small error causing some big problems.

I still need to make the call on my build whether to roll the dice on the simple SAFC or MAFT-pro route or dive into an AEM or ECU Masters.
 

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Yes, you do not have timing control with the stock ECU. And you will make more power with a stand alone. I made 495rwhp on a GT35R at 17psi with my built 7M(cams/headwork) on pump gas with an AEM ECU. For a not apples to apples comparison, I made 511rwhp with a stock 7M at 25psi on a C16/93 mix. I usually kept it at 18psi for pump gas which was around 400rwhp.

I've probably made over 100 1/4 mile passed with the stock 7M on the stock ECU anywhere from 400-511rwhp, with a best pass of 12.0 at 120mph. I did lift my head once (and burned up a couple of clutches, but never any other damage.

The stock ECU with an AFC is just super easy to tune and keep reliable even up to 500rwhp as long as you have octane. The AEM I had(my only stand alone experience) was just a lot more complicated. It will make better power, especially on pump gas, but not worth the trouble at this power level in my opinion.
 
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