Jump to content
The mkiv Supra Owners Club

True Twin Turbo Conversion???


mattysupra

Recommended Posts

Guest milllane

Hi,

 

I`d like to give my input on this, I work on a customers TT auto who tells me what he wants me to do after reading up on websites etc, as it is I have done the following :-

 

True Twin Conversion vacuum way.

Manual boost controller

Boost guage

Fuel cut defender HKS

Full turbo back Blue flame exhaust, no restrictor rings

Custom induction kit made by me

Uprated fuel pump

Denso iridium plugs

 

Ok it was running rough a few weeks ago and in the end I got it down to the new plugs being gapped wrong, adjusted the gap and perfect running, best its ever been in the 2 years I`ve looked after it.

I booked it in for a rolling road session at Triton Motorsport and it produced 342 rwhp @ 15psi which I thought was pretty good and the guys there said the fuelling etc was spot on and it needed no other work.

The back turbo has rattled for approx 12 months, the boost controller lets it run upto the end of the boost guage @ 20psi with no ill effects and this is how it is set everyday. He drives it hard and does regular track days, never misses a beat and never any problems.

 

Just my take on the true twin setup. :p

Link to comment
Share on other sites

Well thanks for the replies everyone. I think i will leave it alone as I'm to scared of melting valves again I was worried about fuelling and it seems others are to. I guess on a stock or mildly modified supra you may be o.k but mine is far from stock and guess i shouldn't be messing with what seems a good reliable set up (11.9 quarter ) Thanks for all the info.

Link to comment
Share on other sites

Hi,

 

I`d like to give my input on this, I work on a customers TT auto who tells me what he wants me to do after reading up on websites etc, as it is I have done the following :-

 

True Twin Conversion vacuum way.

Manual boost controller

Boost guage

Fuel cut defender HKS

Full turbo back Blue flame exhaust, no restrictor rings

Custom induction kit made by me

Uprated fuel pump

Denso iridium plugs

 

Ok it was running rough a few weeks ago and in the end I got it down to the new plugs being gapped wrong, adjusted the gap and perfect running, best its ever been in the 2 years I`ve looked after it.

I booked it in for a rolling road session at Triton Motorsport and it produced 342 rwhp @ 15psi which I thought was pretty good and the guys there said the fuelling etc was spot on and it needed no other work.

The back turbo has rattled for approx 12 months, the boost controller lets it run upto the end of the boost guage @ 20psi with no ill effects and this is how it is set everyday. He drives it hard and does regular track days, never misses a beat and never any problems.

 

Just my take on the true twin setup. :p

 

 

 

So you are saying that you gapped the iridium plugs?

Link to comment
Share on other sites

Guest milllane

Well yes and no, Triton Motorsport did it for me, out of the boxes the plug gaps were way out, why whats the issue with that?

 

I didn`t post to be told I am doing hack jobs either, as I said in the first place I do what the customer asks as I do not profess to be a jap expert!

Link to comment
Share on other sites

Guest milllane
From someone that gaps iridium plugs that doesn't inspire me with confidence.

 

TTC with a bleed valve and no ECU mapping is a real hack job IMO - much better off running sequential the way Toyota intended.

 

So whilst I appreciate what your saying and yes it were my own I`d do it properly, how do you justify that the fuelling etc was apparently spot on?

Link to comment
Share on other sites

It won't have been - they're talking out their arse. In my humble opinion!

 

For info, that set of iridium plugs you gapped are now at risk of breaking up and destroying your customer's engine. They come pre-gapped and yes it is supposed to be a very small gap - NOT the 1.1mm standard gap that Toyota specify.

Link to comment
Share on other sites

Guest milllane

But the car would not run properly with the gap they had so what are you supposed to do?

Also it suprises me because Triton Motorsport are Japanese specialists and have a great reputation.

Link to comment
Share on other sites

But the car would not run properly with the gap they had so what are you supposed to do?

Also it suprises me because Triton Motorsport are Japanese specialists and have a great reputation.

 

In that case they should know better. Is the owner on this forum? What were the gaps and what did they set them to?

Link to comment
Share on other sites

There is no way the fuelling will be fine in TTC, it will have a weak spot as both turbos start to make boost and it will go just as pig rich as most BPUs at 1.0 BAR which i suspect may be the misfire problem, unless one of the iridiums is fooked already.

 

:yeahthat:

 

Maybe regapping the iridiums is masking an issue, like a weak coil pack. If that is the case then the misfire will come back eventually.

 

-Ian

Link to comment
Share on other sites

  • 2 weeks later...

as I said in the first place I do what the customer asks as I do not profess to be a jap expert!

 

This is a very worrying statement.......:blink:

 

A mechanic that does what the customer asks for and not what he believes or knows is right......there are too many outfits that operate like this and when things go wrong, they usually come back with "well, its what you asked for".........just like No1 and his EFMIC.......:(

Link to comment
Share on other sites

OK guys i have a quick question. Was getting a bad misfire on 2nd turbo. everything seemed to be fine. Done this TTC mod and 2nd turbo runs fine. Now my question is that i know the fuelling and that will be out but will it 1) damage my engine? 2) will the fuelling be out by alot as its stock with all cats in etc..

 

I do have a boost controller, how would i need to set this up to stop boost spikes?

 

Ok more than a quick question but any help is greatly appreciated.

 

Surj :)

Link to comment
Share on other sites

OK guys i have a quick question. Was getting a bad misfire on 2nd turbo. everything seemed to be fine. Done this TTC mod and 2nd turbo runs fine. Now my question is that i know the fuelling and that will be out but will it 1) damage my engine? 2) will the fuelling be out by alot as its stock with all cats in etc..

 

I do have a boost controller, how would i need to set this up to stop boost spikes?

 

Ok more than a quick question but any help is greatly appreciated.

 

Surj :)

 

The fueling will only be out below 4k rpm, as then as far as the ECU is concerned there is no possibility of the no.2 turbo running, above 4k rpm everything is fine......;)

 

But even below 4k rpm, I dont think its so much you WILL ruin your engine, but your AFR's could be a bit risky......but as I said I ran with this mod for a while, no issues.....

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.