My 88 Part List

[EthanMKIII]

What Hp are u trying to achieve? If your build works good ill probly use similiar parts on my 88. Btw has ur supra blown a Hg yet? Mines at 170,000km and im starting to get worried cause it could blow anytime.

[Grandavi]

Originally Posted by EthanMKIII

What Hp are u trying to achieve? If your build works good ill probly use similiar parts on my 88. Btw has ur supra blown a Hg yet? Mines at 170,000km and im starting to get worried cause it could blow anytime.

I am not totally sure about the final HP i want to achieve to be honest. These would be the priorities:
1. Longevity (none of us want to build it twice)
2. Economy (squeeze the MPG's out of it when not having fun)
3. Performance (this is a combination of the first 2, but also the feel of being thrust forward.. its why I like the car so much)

The HP at final stage really wont be known unless I up the Turbo size. Because at that point, I will be doing serious mods and thats not my original intent.

My engine has approx 22,000 km on it (about 13,000 miles). As far as I know, the head gasket is fine. Yours should have failed already at your mileage if it is going to. I have been told by a few people that the one thing to do to prevent BHG in MKIII's is to upgrade the rad first. Only redo the headgasket (put in a MHG) if you are going to be upping the boost to higher levels. If I go that route, I think I may swap engines totally anyway to the JZGTE variant with a new tranny although I havent researched that route yet, but apparently thats the road for 450+ HP. Honestly, I dont think I have enough personal restraint for going that direction as I find it hard not to race when challenged (unless I dont think its an open road and it looks unsafe.. I'm old enough to see the danger)

I just want to keep my Supra for a long time and enjoy it and I miss working on cars (haven't worked on a car in over 20 years now, so this is like a flashback to youth)

[TheMark3]

I don't get it. You say you are holding off on a turbo but you are buying this: 7MGTE T4 Flanged Exhaust Manifold? Does that leave anything in the same place so that you could buy pre-fab downpipe and catback systems? I would think that you would be largely on your own fabricating your entire exhaust once you got that. Is your stock turbo going to bolt up to that? Am I missing something?

[Grandavi]

Originally Posted by TheMark3

I don't get it. You say you are holding off on a turbo but you are buying this: 7MGTE T4 Flanged Exhaust Manifold? Does that leave anything in the same place so that you could buy pre-fab downpipe and catback systems? I would think that you would be largely on your own fabricating your entire exhaust once you got that. Is your stock turbo going to bolt up to that? Am I missing something?

The car has the stock turbo... I meant I dont intend to upgrade it (although, who knows). With that manifold, I may need to do some fabrication, but wont know until I get all the pieces in one spot to match em up and see how they will fit. Exhaust fabrication isn't really a big deal as long as there are no additional big bends. If you happen to know of a better exhaust/manifold header that would be better overall, I posted this list so that people could correct my choices or offer up options (thats the reason I'm not moving really quickly, I dont want to do it twice and all of these parts are new to me.. its been 20 years since I worked on my own car)

[TheMark3]

Originally Posted by Grandavi

The car has the stock turbo... I meant I dont intend to upgrade it (although, who knows). With that manifold, I may need to do some fabrication, but wont know until I get all the pieces in one spot to match em up and see how they will fit. Exhaust fabrication isn't really a big deal as long as there are no additional big bends. If you happen to know of a better exhaust/manifold header that would be better overall, I posted this list so that people could correct my choices or offer up options (thats the reason I'm not moving really quickly, I dont want to do it twice and all of these parts are new to me.. its been 20 years since I worked on my own car)

OK - but I don't think the CT26 turbo will bolt to that manifold as it does not mount to a T4 flange that I have ever heard of. So you would use - an adapter? Then exiting the turbo you likely will have alignment issues. If you do change the location of the exit from the turbo - then I would not waste money on the downpipe as you will probably wind up butchering it. I am just wondering about the need for the manifold at all - unless you are planning 10s in the quarter mile or something. Without the manifold the rest all makes perfect sense.

[Grandavi]

Originally Posted by TheMark3

OK - but I don't think the CT26 turbo will bolt to that manifold as it does not mount to a T4 flange that I have ever heard of. So you would use - an adapter? Then exiting the turbo you likely will have alignment issues. If you do change the location of the exit from the turbo - then I would not waste money on the downpipe as you will probably wind up butchering it. I am just wondering about the need for the manifold at all - unless you are planning 10s in the quarter mile or something. Without the manifold the rest all makes perfect sense.

Ahh, this is the first I have heard of what you are saying. The whole problem is I am reading a lot of bits and pieces of information and trying to follow it without any real hands-on. Therefore I may be confused (which is why I posted this in the first place ). Originally I was against upgrading my turbo, but after reading as much as I can and talking to various people, I am thinking I may have to upgrade it as well as do some other modifications I did not plan on (which I am still trying to hammer out prior to posting more here so I dont confuse the people I am hoping will "unconfuse" me!).

My plan is to try to get as close to 300 HP as possible without going too far from stock or without putting too much pressure on the engine. However, after 2 weeks of studying this (and I may still be incorrect), it seems that there is a "jump point" from approx. 250HP max stock to 450 HP modified. I dont think there is any true middle ground.

The intention of the exhaust manifold or getting a tuned header was to do a simple bolt on improvement as I have read (again.. this is not "hands-on" knowledge, so I am searching for confirmation) that the stock manifold has some issues with backflow due to poor or improper design.

Now... at the risk of doing a text wall, I have found that if I increase an 88 Supra 7MGTE exhaust to 3", the I may be sacrificing low end torque for high end torque (meaning slow at the start, fast at the finish). This isn't what I intend to do at all. So... to sum it up, I will just state what I am trying to accomplish.

My entire "vision" is to have this engine running at top performance with approx. 300-325 HP and doing it as close to perfectly as possible. There are no limitations on the $$ side to achieve this, Im just hoping to do it smartly without spending too much money (isn't that what we all try for?). This car will be my daily driver so economy is a consideration although if I have to sacrifice some fuel for performance.. than so be it!

This exhaust manifold may indeed be wrong for the entire set up as I have learned much more than when I originally posted it. I'm thinking I may have read too much, so am mixing projects up in my tiny brain and cross referencing wrong so that is why I myself may be wrong on my selection.

If you have know of a post here or have information that can steer me right, I would greatly appreciate it. This all ties into having a 3" exhaust to eliminate backpressure.

[TheMark3]

I'm in pretty much the same boat as you - with current set up - a bone stock 86.5 Turbo and no practical limit to the money spent - but don't want to be stupid about it. I also would like to bump it up to around 300-350 hp. Really it is all stupid as I run it 99.9% of the time like the old man I have become - but toys are toys.

I have not heard that the low end will suffer from going to a 3" exhaust.

The prescription given to me for that amount of power is as follows:

3" cat back
elbow/downpipe
hardpipe ic piping
boost controller.

...they said that should bring me to the verge of the power I want - to continue:

Lexus AFM
550 cc injectors
modified CT26
piggyback ecu - or modified air screw for the AFM
walbro fuel pump
tuning time at a dyno

...they say this can easily exceed the upper end of my expectations. Here is where they cautioned me: picking the modification level of the CT26. Put a huge compressor wheel on it and you will see large lag times and then a huge hit of power. At this point it becomes less streetable. Somewhere in the 52 to 57 trim level seems to be a good middle ground. Nowhere yet is any mention of a new manifold either. The piggyback ecu and a wideband sensor will give most power - although I am trying not to have a modified interior on mine and all of the electronics will cramp that.

I am going to aim for the first batch of mods and see where it gets me, then consider the second batch.

I will also say that with this done you can easily get yourself into more trouble than even the car can handle. I would not go crazy on the engine without considering brake and suspension upgrades.

[EthanMKIII]

well wiki said 160Miles mines only 170km 160miles is around 200k so i dk i have no symtoms of a BH but i have put a new rad in her.

[Grandavi]

Originally Posted by EthanMKIII

well wiki said 160Miles mines only 170km 160miles is around 200k so i dk i have no symtoms of a BH but i have put a new rad in her.

Yeah, what I am saying is that hopefully its already been dealth with. At that many miles (km) on the car, I would think any BHG issues would have shown up already and been dealt with. Although, mine has been rebuilt and I know its not the Toyota HG in it, but the Toyota Head bolts are still there. Without tearing off the top of the motor, I havent been able to see if they have stretched or even been torque'd correctly. I have read that the ARP head bolts get torqued to 75 lb/in. but the original torque specs stated 55.. which was where the trouble all started.

And as for new rad... is it a bigger rad? (Remember, I am not an expert or even a mechanic.. just a fellow Supra owner) From all that I have read and been told, you want to get a "better" rad than stock because it is small for the amount of heat this engine generates.