would appreciate some well known guidance to help upgrade my bone stock '97 MKIV auto

[jzzrs180]

Hey hey everyone.

I am purchasing a stock '97 MKIV, I have done my fair share educating myself on BPU's n APU's, and from that have certain goals I want to accomplish, yet still proceed with the proper steps necessary to avoid disaster. The ultimate goal is to achieve the least amount of turbo lag with immediate response, and still feel the power band the whole way. I don't need a crazy 1000hp monster, I'd prefer a smooth street driven 700-800rwhp max/w adjusted suspension, and still keep the originality of the car. Am I missing anything from what I have listed so far?

1ST Bundle
1.ebc or mbc (electronic/manual boost controller)
2.greddy BCC
3.downpipe with high flow catalytic converter
4.exhaust
=From my understanding this will equal to around 370-410rwhp.

2nd Bundle
1.turbo(s) upgraded
2.HKS fmic/piping/water pump/ thermometer
3.adjustable cam gear(s)
4.Paxton upgraded fuel system/w (720 injectors?)

Is it cheaper to upgrade to a single turbo rather than twin, and do I still benefit from a blowoff valve in an auto? Any other recommendations or opinions would be appreciated as well! Like what is unnecessary for upgrading i.e. intake manifold?

[pwpanas]

Originally Posted by jzzrs180

Hey hey everyone.

I am purchasing a stock '97 MKIV, I have done my fair share educating myself on BPU's n APU's, and from that have certain goals I want to accomplish, yet still proceed with the proper steps necessary to avoid disaster. The ultimate goal is to achieve the least amount of turbo lag with immediate response, and still feel the power band the whole way. I don't need a crazy 1000hp monster, I'd prefer a smooth street driven 700-800rwhp max/w adjusted suspension, and still keep the originality of the car. Am I missing anything from what I have listed so far?

1ST Bundle
1.ebc or mbc (electronic/manual boost controller)
2.greddy BCC
3.downpipe with high flow catalytic converter
4.exhaust
=From my understanding this will equal to around 370-410rwhp.

2nd Bundle
1.turbo(s) upgraded
2.HKS fmic/piping/water pump/ thermometer
3.adjustable cam gear(s)
4.Paxton upgraded fuel system/w (720 injectors?)

Is it cheaper to upgrade to a single turbo rather than twin, and do I still benefit from a blowoff valve in an auto? Any other recommendations or opinions would be appreciated as well! Like what is unnecessary for upgrading i.e. intake manifold?

1) Will you be purchasing a TT or an N/A? If TT, is it a US-spec or Japanese-spec?
2) What kind of fuel do you plan to run? A bpu Mkiv TT only makes 410rwhp using a blend of race fuel and 93 octane pump gas. If you try to make 410rwhp with the oem twins using 93 octane pump gas you'll detonate and gradually (or rapidly, depending on the boost level) deteriorate your engine's compression ratio.
3) You'll need a boost gauge (some boost controllers come with this)
4) You'll make more power with a straight-through downpipe than with a high-flow cat
5) You can move the adjustable cam gears up to bundle#1
6) Why did you pick a "Paxton" fuel system?
7) The oem water pump works just fine. What did you mean by "thermometer" in bundle#2, point 2.?

[jzzrs180]

I will definitely be purchasing a U.S.TT, and with fuel, can you explain why I have an option? I just figured since it's a high performance engine 93 was the way to go, although I've heard people using fuel flex b4 but don't know enough about it, other than, it's somehow programed with the ecu.. But you're saying if I use the oem twins that I'm not producing enough air to match my fuel intake with higher boost, causing detonation, or basically that my air/fuel ratio is too lean? If so how do I create a perfect ratio, does it depend on my boost? The AEM Tru boost controller comes with an all in one gauge and from that, I read it's highly recommendable. And yes definitely aware that a cat-less downpipe makes more power but I read its only a difference of like 12hp, and with emissions and all, I'd opt to still possess the legal high flow cat..Also can you please explain the adjustable exhaust cam gear, in relation with TDC and if that will help prevent pre-ignition or detonation? And I read somewhere that the Paxton fuel system was popular among Supra owners that why i mentioned it.. The thermometer I mentioned because I read that increasing hp past 500 hp would require an upgrade to the whole fuel system, including the water pump and thermometer etc..Also can you explain the difference between the 4 speed auto ECT to the 4 speed ECTi? I read it was optional on the autos, but don't know when n why it became an option, 93-98? Thanks! Love Supra's and want to know everything I can so to approach my ideal specs.

[pwpanas]

Originally Posted by jzzrs180

I will definitely be purchasing a U.S.TT, and with fuel, can you explain why I have an option? I just figured since it's a high performance engine 93 was the way to go, although I've heard people using fuel flex b4 but don't know enough about it, other than, it's somehow programed with the ecu.. But you're saying if I use the oem twins that I'm not producing enough air to match my fuel intake with higher boost, causing detonation, or basically that my air/fuel ratio is too lean? If so how do I create a perfect ratio, does it depend on my boost?...

The fuel's octane requirement has almost nothing to do with air:fuel ratio (that's taken care of by the oem maf and/or Turbo Pressure Sensor, together with the oem ecu).

The fuel's octane requirement has everything to do with the increased cylinder pressures and temperatures associated with increased boost. If you raise the boost without sufficient octane, the fuel will detonate, blowing holes in the expensive 2jz-gte internals. Please forget about lean and rich, and start thinking about more octane for more boost.

Originally Posted by jzzrs180

...Also can you please explain the adjustable exhaust cam gear, in relation with TDC and if that will help prevent pre-ignition or detonation?...

The adjustable cam gears have almost nothing to do with detonation (that's boost and octane - see above). The adjustable cam gears allow you to re-tune the peak power/efficiency point of the engine so that you can squeeze out a bit more hp at higher rpms.

Originally Posted by jzzrs180

...And I read somewhere that the Paxton fuel system was popular among Supra owners that why i mentioned it....

Wow - crazy. Please forget this, because it's terribly irrelevant. Paxton makes superchargers. If by some weird coincidence they have actually begun making a fuel system for the Mkiv Supra Turbo, please trust that it would be a very rare and unpopular component - at least in the US. Also, they're so d@mn proud of it that it isn't promoted anywhere on their web site.
I've been upgrading (directly and indirectly) literally hundreds of Mkiv Supra Turbos since the mid '90s and I've never heard of it. If it ends up that you need a fuel system, I'll get you pointed in the right direction - there are several good choices.

Originally Posted by jzzrs180

...The thermometer I mentioned because I read that increasing hp past 500 hp would require an upgrade to the whole fuel system, including the water pump and thermometer etc...

Sorry, now you have me even more confused. What does "hp past 500" have to do with a thermometer????

Originally Posted by jzzrs180

...Also can you explain the difference between the 4 speed auto ECT to the 4 speed ECTi? I read it was optional on the autos, but don't know when n why it became an option, 93-98? Thanks! Love Supra's and want to know everything I can so to approach my ideal specs.

I believe that the "i" stands for "with intelligence". It's the same marketing term that Toyota uses for it's VVTi technology.

Again:
1) US-spec Mkiv TT, right? Auto or 6spd?
2) What kind of fuel do you plan to run? If you limit yourself to 93 octane ((R+M)/2), then you'll be limiting yourself to about 15psi of boost with the oem twins and the oem ecu.
7) ...What did you mean by "thermometer" in bundle#2, point 2.?
...and to add to that:
8) What is your horsepower goal? 800rwhp? If so, that definitely ain't happenin' on pump gas lol. You'll need a full fuel system too (but not a "Paxton").
9) Do you intend to stay with the oem twins or go to a single turbo? About 450rwhp is max (6spd) with the stock twins, so I guess they're out. Right?
10) What is your application (roadracing, daily driving, drifting, drag racing, autocross, top speed, etc.)?

[jzzrs180]

Ok cool So talking stock MKIV TT here for a sec, I mentioned air:fuel ratio because for example, if a sports car uses increased air (the twins) to increase the cylinder pressure, you would need a high octane gas like 93 to be able to ignite it at the right time, and burn that off efficiently. But I guess what you are saying is, (if I have you right), that if I were to manage a good bpu I wouldn't have to worry about air:fule ratio because your the ecu reads your increased air automatically and auto corrects your fuel consumption? (Please bare with me LOL) So then, can you explain how and where do I get this mixture of higher octane fuel, and is it stored in the main fuel cell together? What is that ratio lol? sounds like a pain in the ass to fill up..ha. I always thought 93 was good enough..(BTW I collected all my questions for ya at the bottom)



Do you mind diving into the adjustable cam gear thing a little more for me if you don't mid. My understanding was controlling the cam gears with opening n closing of the valves in relation to TDC is basically how to improve hp, but why? Because you're allowing more fuel and air in longer before TDC? If so why is the exhaust gear more important to adjust, and what are the popular degree(s) for a bpu, with say.. 15psi?

As for the Paxton system, saw it on this guys youtube upgrade vid I believe and again somewhere else..BUT, I will take your word for it!! LOL, what are your top 3 favorite systems or the 3 most popular?

And to clarify the thermometer thing, sorry I was saying I thought if you increase your hp past say 500hp that you would have to upgrade your cooling system, which includes radiator, water pump, piping, probably your fmic, and the thermometer, along with the fuel system, fuel lines, pump, filter, injectors..Since the stock system has trouble keeping up with the added power. Am I correct?

Yes it's intelligence (ECTi), that I knew, and my guess is that it just means better response with your throttle at low and high rpms.. I just wanted a more clear understanding if you could clarify better.

Again:
2) What kind of fuel do you plan to run? If you limit yourself to 93 octane ((R+M)/2), then you'll be limiting yourself to about 15psi of boost with the oem twins and the oem ecu.

Well since today I was not aware that 500hp, 600hp, etc. upgrades required higher than 93 octane fuel..naive me!! This is what I pulled off of Wikipedia--"Racing fuels, avgas, liquefied petroleum gas (LPG), and alcohol fuels such as methanol, may have octane ratings of 110 or significantly higher. Typical "octane booster" gasoline additives include MTBE, ETBE, isooctane and toluene". So again how, and where, and at what ratio do I make this fuel work for me?


8) What is your horsepower goal? 800rwhp? If so, that ain't happenin' on pump gas lol.

I saw somewhere that a guy was running high horsepower on a flex fuel mix, know anything about that? He had a youtube vid and all, him at the gas pump filling up 85 with a gauge, and then filling the rest with another fuel..And yes I eventually wanted to reach the 7's or 8's in hp, or until I'm satisfied with where I'm at. Listening and learning from pros like you will help me get a better understanding of my goals. I must say though, it is a craft I want to someday master!

9) Do you intend to stay with the oem twins or go to a single turbo? About 450rwhp is max (6spd) with the stock twins, so I guess they're out. Right?

For a bpu, idk... i guess see as I go? Eventually I'd like to hit those higher horse numbers like I already mentioned, but do I have to then switch to a single? I have seen most nutty 1000hp Sup's (or some with a little less) possess single turbos, but also heard/seen a few that maintained upgraded twins as well, is that unnecessary because of cost to stay with twins? One of my ultimate goals is a strong, quickly responsive powerband all the way through with as little lag as possible starting at low rpm, yet still able to drive it like a regular stock toyota Somehow that still screams twins to me..! And I heard you can achieve these goals in the 700's still when talking horsepower.. So to answer your last question, it's definitely not drifting or drag racing, or autocross I desire. I'd say between weekend driving, and road racing, kinda like a "cheetah", bursts of insanity when I want, but mostly daily lounging around like if I was driving a KIA lol, so smooth.. With road racing upgrades where does that get me in top speed, because I do miss 155mph! LOL used to have a street bike..ha, and boy did I test that thing..Oh and btw I have to have an auto not a six speed, not because I couldn't find one or preference. Because I had a serious motorcycle accident when I was 23, i'm 28 now, that it put me in a manuel wheel chair..whack I know! Yet kinda ironic considering the manuel thing, ha ha.. But I would install a simple hand control for the Sup like i have now in my current car. I Could always dive anything, "just give me a day", I'd say lol. Used to drive stick shift in my sleep, that was the only way to go but now it's not an option....Anyway, I read that the oem auto tran can handle up to 500hp and no more, true?

Also I read that all systems are controlled by an integrated engine management system (ems), consisting of a main engine control module (ecm) and several peripheral electronic control units (ecu) for the ancillary systems. How does the obdII play into that system, and if I were to upgrade to a AEM ems, how does that work with the rest of the system, i.e. ecu, ecm? Thanks for the response and the help so far btw!

1.can you explain how and where do I get this mixture of higher octane fuel, and is it stored in the main fuel cell together? What is that ratio?

2.why is the exhaust gear more important to adjust, and what is the popular degree(s) for a bpu, say.. 15psi?

3.what are your top 3 favorite fuel systems or the 3 most popular?

4. Complete upgraded coolant and fuel systems past 500hp, but with lower horses I'm ok with oem? flex fuel mix (85)?

5. How does the obdII (on-board dia.) play a role into that Sup's ems system, and if I were to upgrade to a AEM ems, how does that work with the rest of the system, i.e. ecu, ecm?

6. Say I make a bpu where I maintain about 15psi for now, where does the equate in relation to hp?

7. Pros n cons of single turbo and/or twins?

8. Stock auto tran can handle no more than 500hp?

[jzzrs180]

Was looking into a '97, but was also looking at a '94 TT with a great price, the only turn off really was the miles..What do you think?

Current miles: 88,929
1994 TOYOTA SUPRA TWIN TURBO.. BONE STOCK.. ALL ORIGINAL.. NO PAINT WORK.. CLARION CD PLAYER.. LEATHER.. LOW MILEAGE.. FULLY SERVICED.. HANDFUL OF SERVICED RECORDS.. ADULT OWNED.. FLORIDA CAR..

A few little dislikes, one that it has that aftermarket cd player, that it's not a T-top, and I love the '97 front and back ends..minuscule details but would like to hear some feedback. Also any extra recommendations to ask about/look for when buying a car like a Sup? I know test drive and compression test of course.

[Codyjamesuno]

Originally Posted by jzzrs180

Was looking into a '97, but was also looking at a '94 TT with a great price, the only turn off really was the miles..What do you think?

Current miles: 88,929
1994 TOYOTA SUPRA TWIN TURBO.. BONE STOCK.. ALL ORIGINAL.. NO PAINT WORK.. CLARION CD PLAYER.. LEATHER.. LOW MILEAGE.. FULLY SERVICED.. HANDFUL OF SERVICED RECORDS.. ADULT OWNED.. FLORIDA CAR..

A few little dislikes, one that it has that aftermarket cd player, that it's not a T-top, and I love the '97 front and back ends..minuscule details but would like to hear some feedback. Also any extra recommendations to ask about/look for when buying a car like a Sup? I know test drive and compression test of course.

thats low miles if you ask me as long as its been maintained. Looks like a nice find, but the TARGA is an awesome option that I would not go without.

Good Luck!

[jzzrs180]

I hear ya! The targa model ironically weighs a little more too lol, but that's no real matter, definitely would help me make that decision a little easier.. The only real doubt i have though is telling myself that I just put down over $20k on a car that has just under 90,000 miles, and being ok with it.. If I'm patient, I can justify waiting longer, saving up and putting $30k down for one that has 30-40,000 miles, which would make me feel like I'm still buying a new car..But that's where I'm torn, it does look in great shape and it is a good price for the TT..sooo are the miles really that big a deal!? it's an 7 hour drive north if I wanna check it out..

[pwpanas]

Originally Posted by jzzrs180

if a sports car uses increased air (the twins) to increase the cylinder pressure, you would need a high octane gas like 93...

Sorry gotta stop you right there. 93 octane (r+m)/2 pump gas is only 88 motor octane. Rather pathetic, actually. High octane fuel is something like this:
http://www.vpracingfuels.com/page499588.html

Originally Posted by jzzrs180

...to be able to ignite it at the right time, and burn that off efficiently.
But I guess what you are saying is, (if I have you right), that if I were to manage a good bpu I wouldn't have to worry about air:fule ratio because your the ecu reads your increased air automatically and auto corrects your fuel consumption?...

Actually, I'm saying that and a whole lot more. Too much boost using lower octane fuel explodes (i.e. detonates), it doesn't burn...which blows holes in your pistons.

Originally Posted by jzzrs180

...So then, can you explain how and where do I get this mixture of higher octane fuel, and is it stored in the main fuel cell together?...

Yep, or you can inject it separately - your choice.

Originally Posted by jzzrs180

...What is that ratio lol?...

Lol? Tell me the boost you want to run and I'll tell you what ratio to use. Not sure what the Lol is about...it's pretty simple.

Originally Posted by jzzrs180

...sounds like a pain in the ass to fill up..ha....

Not nearly as big a pain in the ass as swapping your pistons out after blowing holes in them. HA!

Originally Posted by jzzrs180

...controlling the cam gears with opening n closing of the valves in relation to TDC is basically how to improve hp, but why?...

Again, you don't improve hp, you just move the peak efficiency curve of the engine so you can make more max hp. You give up a bit of bottom end hp and torque, but that's easily corrected by a downshift.

Originally Posted by jzzrs180

...what are the popular degree(s) for a bpu, with say.. 15psi?...

http://www.mkiv.com/techarticles/cam...all/index.html
"On exhaust gear, retard -3 (deg.), on intake gear, advance 1 (deg.)."

Originally Posted by jzzrs180

...what are your top 3 favorite systems or the 3 most popular?...

To be honest, my favorite was the one I designed and sold, but don't anymore. Sadly, the higher-end components I used didn't allow it to be sold at a competitive price. Regardless, here's one that I'd be comfortable recommending:
http://www.spracingonline.com/store/..._MKIV_Supra/17

Originally Posted by jzzrs180

...And to clarify the thermometer thing, sorry I was saying I thought if you increase your hp past say 500hp that you would have to upgrade your cooling system, which includes radiator, water pump, piping, probably your fmic, and the thermometer, along with the fuel system, fuel lines, pump, filter, injectors..Since the stock system has trouble keeping up with the added power. Am I correct?...

No, I didn't say that at all. Actually, I'm pretty confused about how you could have possibly misread that into any of my posts. Weird. Perhaps you were thinking that a better cooling system would make low octane fuel burn cooler under high boost? If that's the case, then sorry it won't. The cooling system pulls heat out of the metal in the head and the block - which only has a minimal indirect impact on the combustion temperature. Think about it this way - let's say I'm running a Supra in Alaska in the wintertime. The Supra has a single turbo and is configured to push 30psi+ of boost. The ambient temperature is 75 degrees below zero. I fill 'er up with 93 octane (88mon) pump gas and within a few seconds I hit my 30psi of boost. What happens? Of course, this is a bad idea with a cold engine because I'll probably throw a bearing, but putting that problem aside for the moment, I'll still blow holes through the pistons because of detonation. The cooling system is completely irrelevant in this situation, because the metal in the engine is still bone cold. So even with a crazy-cold motor the combustion temperature and pressure and the low octane of the fuel are the important pieces of the puzzle. Get it?

Summary:
Either way, the entire oem cooling system (including the "thermometer" aka temp sensors) is just fine to well over 750rwhp.
The oem fuel system is an entirely different story - the US-spec Mkiv Supra Turbo's oem fuel system can only handle about 550rwhp max - if all of the components are in brand-new condition.

Originally Posted by jzzrs180

...my guess is that it just means better response with your throttle at low and high rpms.. I just wanted a more clear understanding if you could clarify better....

Sorry don't know much about the oem Mkiv auto - hopefully another forum member can help you out here. Mine's a 6spd.

Originally Posted by jzzrs180

...how, and where, and at what ratio do I make this fuel work for me?...

Depends on how much boost you want to run.

Originally Posted by jzzrs180

...Eventually I'd like to hit those higher horse numbers like I already mentioned, but do I have to then switch to a single?...

Yep.

Originally Posted by jzzrs180

...I have seen most nutty 1000hp Sup's (or some with a little less) possess single turbos, but also heard/seen a few that maintained upgraded twins as well, is that unnecessary because of cost to stay with twins?...

You can get "upgraded twins" but they're not longer sequential - they're parallel. Most don't go with this because that kit is more expensive and provides no tangible benefit over a single.

Originally Posted by jzzrs180

...One of my ultimate goals is a strong, quickly responsive powerband all the way through with as little lag as possible starting at low rpm, yet still able to drive it like a regular stock toyota...

Sounds like you want to have your cake and to eat it too. Unfortunately big hp turbos don't spool up fast. It's just physics - a bigger turbo compressor wheel is heavier, and takes more exhaust energy via the turbine wheel to spin up. No one has figured out how to defy the laws of physics yet, so this rule always holds true.

[jzzrs180]

It has a car fax, so that's a plus too, I'm basically jumping all over it, I offered $11k down and have been working on getting everything squared away. I've been busy trying to figure out the best way of going about it, but great advice!! And thank you much for the help. I am going to try to find a local dealership there or import shop possibly that can give me a full inspection! I keep ya informed, and I still want to follow up on our bpu discussion.