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Project Supracharger


David P

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Thinking out loud, :think: whatever injectors go in it's going to need a remap so I may as well fast track the last bits before it's done.

 

Fortuitously, during my injector huntings I happened across a perfect and sexy looking valve for the bypass system. :)

 

Using this and then prune the plumbing off the Q45 to clear the sky hook bracket, will leave just the ICV frequency control conundrum to work out later.

 

As long as the lump is still sound, that should bring the conversion up to it's full potential for the remap. :)

 

Forge bypass-valve FMDVECL202

 

attachment.php?attachmentid=183852&d=1397760781

Edited by David P (see edit history)
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Enquiring after fuel injectors led to finding a :think: recirculation valve. :)

 

Enquiring after a trendy used aluminium expansion tank, led to finding :think: a trendy used aluminium expansion tank! :)

 

Enquiring after an MA70 CPS led to finding :think: fuel injectors. :)

 

Such is life? :looney:

 

 

It's a bit like a blind man talking to his deaf wife, yet have learned that the injectors are MA70 GTE fit, 525cc or 550cc and need a bit of kit from a Camry to work, unused sinced cleaned and have flow chart. He reckoned that his MA70 GTE fuel rail would need spacers for them to fit, which sounds a tad odd, but such are such these things.

 

Waiting for him to find their forgotten 'safe place' for pics and dimensions so I can find out exactly what they are, just maybe I'll get lucky? :)

Edited by David P (see edit history)
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enquiring after fuel injectors led to finding a recirculation valve and now, :think: Enquiring after an ma70 cps has led to finding fuel injectors. :)

 

such is life? :looney:

 

It's a bit like a blind man talking to his deaf wife, yet have learned that they're ma70 gte fit, 525cc or 550cc and need a bit of kit from a camry to work, unused sinced cleaned and have flow chart. He reckoned that his ma70 gte fuel rail would need spacers for them to fit, which sounds a tad odd, but such are such these things.

 

Waiting for him to find their forgotten 'safe place' for pics and dimensions so i can find out what they are, just maybe i'll get lucky? :)

 

7mgte. :)

Edited by Morpheus
Because the bloody iPhone won't capitalise on this forum. (see edit history)
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Thank you for your compliments and pleased that you've enjoyed my saga so far. :)

 

I've always tinkered yet never this far from convention, the most important element is determination, knowledge comes because it's needed to be learned.

 

I spend more time tinkering than driving, which is a long and rocky road that rewards me with great satisfactions in my own little odd apparently way. :D

 

A supercharged Supra for a daily drive, makes every day a good day. :)

 

My project gets done here and there on the hop which makes ten fold the challenge, a daily drive and a garage/shed somewhere for a project is the way to go if you do.

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Update:

 

I've bought another set of Precision 550cc, identical to the present injectors, they're used yet have been cleaned and flow tested.

 

The accompanying certificate shows they have a 4% spread, so have sent them to Dan to match up the best 6 from the 12.

 

This will be done and posted back to me on Monday. :)

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The good news is; the matched set of injectors are in and it's all back together again. :)

 

The bad news is; no. 5 injector is still not firing? :(

 

Pulley is sending me another injector driver to swap in to see if that cures it?

 

attachment.php?attachmentid=185069&d=1399221427

 

Old 1 - 105

Old 2 - 107.5

New3 - 108

New4 - 106.5

New5 - 106.5

Old6 - 107

 

attachment.php?attachmentid=185127&d=1399370588

10277544_10152004019067000_4309406589330613372_n.jpg

Edited by David P (see edit history)
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Today began with life on cylinders :think: 2, 3 and 4? :think: :think: :(

 

After cross referencing the Lexus forum wiring diagram with my Supra WSM, I found that the original ignitor wire in B57 on the ECU has to be repositioned to B52. :)

 

Then there was life on cylinders 1, 2, 3, 4 :think: and 6. :(

 

Still no fuel to no. 5, all circuits checked out and tried routing 5 through both channels 7 & 8 on the Injector driver for no change. :(

 

Shane then scurries off down into his Aladdin's cellar where he unearthed a handful of 13 Ohm resistors and knocked up a plug & play resistor circuit. :)

 

 

attachment.php?attachmentid=185071&d=1399221427

 

 

Click - Brooom and Shane's your Uncle, all 6 are up and at it. :)

 

[video=youtube_share;yLF0-KA3xDo]

 

 

My head bump on the plastic bonnet-stay resulted with a "notifiable leak" and the Victory Video paused for First Aid treatment.

 

attachment.php?attachmentid=185070&d=1399221427

 

 

 

 

Proper in the Bush Engineering. :cool: Thank you.

 

AFR is running 14.0 at light throttle and much to the disappointment of a bloke in a Golf GTI, I kept it off boost and below 2.5k rpm and trundled the 20 miles or more home with no probs, including a visit to Maplins for 6 x 6.8 ohm resistors and a Sunday Lunch at the Pub on my way. :)

 

The Injector Driver doesn't function on channels 5, 7 or 8, that's 3 different channels 2 of which are believed previously unused, which means that my old money diagnostics can't lay the blame squarely on it until after testing Pulley's driver in the circuit Gary.

Edited by David P
Corrected 3.25 Ohm to 13 Ohm (see edit history)
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Glad to be of some help and to get you mobile again. For the record they were 13 ohm resistors and with 2 in parallel giving us 6.5 ohm which was then wired in series with the injector coils in place of the aem injector driver. Those resistors had been in my basement for at least 20 years, I knew it was a good idea to keep them.

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I couldn't remember the number, I knew you had doubled them up to get 6.5, which I halved to end up with the 3.25 old wives tale. :blush:

 

Easy mistake, Resistors in series: R req = R1 + R2. Resistors in parallel: R req = (R1R2)/ (R1+R2)

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What's the resistors for. Could you explain in non-AEM logic terms. Hard to keep up a man of my caliber of course!

 

The resistors are a makeshift resistor pack because the Injector Driver wasn't firing injector 5?

 

I don't know if it's an injector driver or ECU fault until I have tried Pulleys driver.

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The ECU runs all 6 fine with a resistor pack yet with the injector driver it won't run no. 5?

 

It could turn out to simply be a button pressing exercise that's beyond my present knowledge.

I believe your button pushing to be fine within the remits of a diyer. What I am unsure of is the general understanding of the high\low impendance injector thing. With the limited time I have had today to research this, I strongly suspect that because Toyota used 6r8 resistors in series with their injectors/ecu combo that many people assumed that's the value to use. Maybe with an OEM ecu it is, but with a standalone I am not so sure......yet. Convince me someone please.

Edited by Shane
added the word someone. (see edit history)
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http://www.megamanual.com/v22manual/minj.htm has some good info. The resistors will not only limit the driver devices current flow, they will also effect the current rise time, so that needs to be taken into account. Most current (excuse the pun) aftermarket ECU's allow software selection of injector impedance, and the resistors are integral to the ECU..
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http://www.megamanual.com/v22manual/minj.htm has some good info. The resistors will not only limit the driver devices current flow, they will also effect the current rise time, so that needs to be taken into account. Most current (excuse the pun) aftermarket ECU's allow software selection of injector impedance, and the resistors are integral to the ECU..

 

That's a very interesting link Chris, thanks. I had found some other similar stuff relating to MS yesterday, but that is much more detailed. David's low impedance injectors are around 2.5 Ohm and he originally had 6.8 Ohm wirewounds in series and the car has been running happily on the V1 AEM now for months like that. However it doesn't run via the AEM peak and hold injector driver driving the injectors directly, injector 5 just doesn't do anything, we haven't scoped it yet as my ancient Telequipment scope that has been in hibernation for at least 15 years wouldn't power up. I have ordered a new one so next time I have chance I can look at what's going on in more detail.

 

However, in the meantime we have pulled the peak and hold driver out and stuffed the 6.5 ohms back in series with the injectors and it runs fine direct from the AEM. I should point out that as David says, we did try two of the spare channels of the driver on inj 5 and it was the same, without looking at what's coming out of both the ecu and the driver it's easy to blame the driver, but I am not so sure. What concerns me is that the driver stages within the AEM V1 ECU have been dissipating way too much current these last few months with less than 10 ohms hanging from them and that the injector 5 driver circuit within the AEM is not at all happy, maybe its suffering(ed) thermal runaway, become noisy, unstable or whatever and that's why the peak and hold module doesn't like what it's seeing. Again a scope will confirm this I know. I know nothing about the AEM V1, but David tells me there are spare injector channels on that also, so maybe this is something that we can try. Do you know if the 9 ohms that he has hanging on the AEM ECU is within the safe operating range of the ECU?

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Were you able to confirm a solid 12v at Injector 5?

That would be the only explanation to why it would work with the resistor and not with the peak/hold driver.

 

N. Negishi

Tech Support

AEM Performance Electronics

 

There's no problem with voltage to injector 5, so AEM are stumped too.

 

After trying an injector driver swap, if that doesn't work and if I can find one, I'll try an ECU swap.

 

If there happens to be someone with a series 1 that I could try, please contact me.

 

Thank you.

Edited by David P (see edit history)
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