Toyota Celica Supra Forum banner

1 - 20 of 117 Posts

·
Registered
Joined
·
1,652 Posts
Discussion Starter #1 (Edited)
Projects completed so I thought I would create a post for those that are interested. I take no responsibility for the repeatably of this conversion.

Basics: Running a 3.0L 6MGE engine in an 86 P-Type with a 7MGE ECU and supporting electronics.

Short Skinny: The car runs well. Cruising on the highway the AFRs are close to 14. In town they seem to be around 13. At wide open throttle the AFRs are around 11, way rich. Dyno showed a 8 Hp drop and a 7 Tq drop with AFR of 11 to 11.5, this is a drop from the 155Hp 165Tq using the 5M electronics. Seems to get way better gas mileage on the highway. I calculated 28.5 MPG the other day on a mostly highway trip. I think I was getting 25-26 highway before.

Needed Changes you MUST do:7M Injectors and clips, 7M ECU, 7M Knock Sensor, and 7M AFM, rewire the injectors, mod the distributer and run an extra wire to the dist..

Helpful Changes you SHOULD do: 7M ISCV, and 7M Cold Start Injector Switch, unplugging the fuel pressure regulator vacuum line.

Modification: Distributer, Wiring Harness, and re-pin of ECU connector.
Mods to the dist:
One tooth needs the be ground off of the two tooth wheel and a magnetic pick up needs to be added. Pics will be added later.



Mods to the harness:
Wires for the extra dist pickup and for the injectors need to be run. It is best to rewire the injectors and not use the stock wires. You will have to add the knock wire if not already wired in.

Re-pin of ECU connector: Varies from year to year. Use EWD supplements.

Things learned:
5M injector wiring is set up to fire ALL injectors at once where the 7M is set up to fire injectors in three patches of two. 7MGE fuel press is 5-7 psi higher than the 5MGE fuel pressure.

Thanks for helping:
Junkie - Aka. Shawn
CRE from supramania - Christoph
935motorsports - Aka. Robert


*5-Nov-07*
I was running lean for quite some time. I decided to look at the fuel pressures for 5M and for 7M. I noticed that the 7MGE has a higher fuel press than the 5M and the 7MGTE. This could be why I was running lean. I unhooked the vacuum line for the fuel pump and it is much better. Unhooking the vacuum line results in the max fuel press. If you look at the TSRM for the 5M and 7M you will see that the max fuel press for the 5M is the min fuel press for the 7M. There is about 5-7 psi difference between the two.
 

·
Registered
Joined
·
1,537 Posts
Very nice! Congratulations on getting this to work! I've been waiting for someone to get this done to see the results. Someone in the Toronto area has been working on this conversion as well.

I have a couple of questions about what you posted...

Dyno showed a 8 Hp drop and a 7 Tq drop with AFR of 11 to 11.5.
Does that mean that you lost 8 HP when you leaned it out from 11 to 11.5? If so, how did you lean it out?
Or, does it mean that you lost 8 HP when you went from the 5M electronics to the 7M electronics?

Things learned:
5M injector wiring is set up to fire ALL injectors at once where the 7M is set up to fire injectors in three patches of two.
I thought the 5M fired the injectors in two batches of 3, not all at once. Injectors 1, 3 and 5 are connected together and 2, 4 and 6 are connected together and each group of 3 has a resistor in the EFI resistor pack under the hood, so I always thought they fired in two batches of 3 injectors.
 

·
Registered
Joined
·
1,652 Posts
Discussion Starter #3
Dean,

Its a drop from the numbers in my sig, thanks for the catch. I edited the 1st post. There was no tuning done to the car.

About the injectors. I though they were two batches of 3 as well, caused me many hours of frustration and a near fire from a hot cat. That turned out not to be the case. If you open up the 5M ecu and trace the injector circuits back a few components they will have a common signal. And if you do a continuity check from the injectors to the ECU plug you will find that you will have continuity to all of them.

The initial injector hook up I did was to leave injectors 2-6 and 3-5 wired into the stock harness, only changing out the connectors. and wiring in injectors 1-4 straight from the ECU. This caused the engine to run extremely rich. To trouble shoot I checked the continuity of the injectors with the pins going to the ECU, the ECU was unhooked from the harness. I had continuity with all of the injector plugs when on pin no.10 and on pin no. 20. To fix the problem I ran new wires from the ECU to the injectors. That solved the problem. The TSRM and EWD both show separate wiring traces going from the injector batches to the ECU. I am not 110% I am correct but I am 99.99% I am correct. I will check the continuity again.

A few years a go when I was building a MegaSquirt system I took apart a 5M ECU and tried to trace the circuit board, I was bored. I noticed that after a few components the injector circuits met and went in to the same chip. I thought I had done something wrong and was frustrated so I didn't look into it any furter.
 

·
Registered
Joined
·
855 Posts
Great job! Glad you got it done. Can't wait to hear what the final numbers are after you get the other parts (injectors, etc.) and get it all tuned up.

Good Luck with it!
 

·
Registered
Joined
·
9,840 Posts
Great job! Glad you got it done. Can't wait to hear what the final numbers are after you get the other parts (injectors, etc.) and get it all tuned up.

Good Luck with it!
It has the 295's in it. The HP loss,I'm sure is in the AFR's. Going from 155whp and 13-13.5 AFR's, to 147whp and 11-11.5 AFR's is major on an NA. Tuning via S-AFC or similar will gain back lost power,then some, I'm sure.

Nice job! Looks like a promising upgrade for a stock ECU-driven 6m-gte

We've discussed this a bit ;) I kinda wish I wanted to turbo a 6m, but, probably won't happen in my shop anytime soon. Again, I think a S-AFC or similar, would be close to enough for tuning. Of course, there are other options to explore with this setup ...
 

·
Registered
Joined
·
855 Posts
Very impressive. So all that's left is tuning. This is great work. Now we have a real application that can be used to compare performance difference between the 5m and 7m heads. Really cool!

Hmmm... a 6m with GTE wiring, injectors, coil, etc.

You all have opened the door to numerous possibilities now. ;)
 

·
Registered
Joined
·
1,652 Posts
Discussion Starter #9
Hmmm... a 6m with GTE wiring, injectors, coil, etc.

You all have opened the door to numerous possibilities now. ;)
Hold that thought.....for about a month.:woot:
 

·
Registered
Joined
·
9,840 Posts
You all have opened the door to numerous possibilities now. ;)

Trying to open up minds, and produce more chatter among the masses also.

We have many very smart people here. Most are afraid to attempt - different - things. This induces an --- it'll never work --- mentality, and that breeds upon itself.

Look at how few participate in any tuning or HP producing threads ...
 

·
Registered
Joined
·
74 Posts
Nice! it does work, I could only get my car to run on 3 cylinders at full throttle LOL. Ill be looking forward to seeing how you modded the Dizzy. BTW congrats on running 7m electronics!
 

·
Registered
Joined
·
9,840 Posts
I'd guess he didn't mod the dist.

I also see potential without a piggyback.

Thought more about this actualy off and on since Darrow stopped by Sun. One of the things we keep forgetting, is going back to our roots, because we rely on technology.

Darrow mentioned pulling the plugs, and that they looked "normal". Yet, the AFR's are way richer than before. Had he been actualy running rich in the comustion chamber, they should have shown signs.

I believe, if you go back to a .070 - .080 or so plug gap on the jacobs, you'll start to see signs of a lean burn, and get the initial HP loss back. I also believe you can advance the exhaust cam, possibly retard the intake, and entrap more fuel/air, and still have the spark to burn it, at probably get a read on the plugs, you deem normal.

What was the plug gap on the 5m electonics ? I know you set it for the 7m stuff at .050, so you could back to back, Toyota vs. Jacobs.
 

·
Registered
Joined
·
2,539 Posts
Hmmm... a 6m with GTE wiring, injectors, coil, etc.
when you say gte are you meaning 7mgte...my concern with that statement is cps...???

however this is a huge break threw! maybe someday it'll be a popular option among the community!
 

·
Premium Member
Joined
·
3,656 Posts
I'd guess he didn't mod the dist.

I also see potential without a piggyback.

Thought more about this actualy off and on since Darrow stopped by Sun. One of the things we keep forgetting, is going back to our roots, because we rely on technology.

Darrow mentioned pulling the plugs, and that they looked "normal". Yet, the AFR's are way richer than before. Had he been actualy running rich in the comustion chamber, they should have shown signs.

I believe, if you go back to a .070 - .080 or so plug gap on the jacobs, you'll start to see signs of a lean burn, and get the initial HP loss back. I also believe you can advance the exhaust cam, possibly retard the intake, and entrap more fuel/air, and still have the spark to burn it, at probably get a read on the plugs, you deem normal.

What was the plug gap on the 5m electonics ? I know you set it for the 7m stuff at .050, so you could back to back, Toyota vs. Jacobs.
What are you guys using to data log? My guess is LM-1, but I'm just curious. Also, the AFC may work OK for taking care of the fuel delivery, but what are you going to do with ignition timing? I'd imagine there's probably a few ponies being left on the table using the stock ECU's timing maps and relying on the knock sensor. I mean...Toyota's a conservative company, and I'm sure their timing curves are a bit on the 'safe' side. I seem to recall that Darrow was planning on nitrous later on...would something like the AEM F/IC handle the timing retard on the button? I realize it's geared more towards the add-on turbo OBDII crowd, but curiosity has me wonder if it would work on an archaic system like TCCS. Just tossing around ideas
 

·
Registered
Joined
·
6,312 Posts
when you say gte are you meaning 7mgte...my concern with that statement is cps...???

however this is a huge break threw! maybe someday it'll be a popular option among the community!
Use the pickups if at all possible in the 6M's dizzy. Can't remember what their tooth count is but should be able to get the same thing from the dizzy.
 

·
Registered
Joined
·
2,539 Posts
so thats all a cps is hmmm? 24tooth is stock... my msii is running on a modded 6tooth from an 82...
 

·
Registered
Joined
·
6,312 Posts
ya 24 and 2 i think the cps is and the 5m dizzy needs a tooth knocked out iirc. Man i should get back to my MS...
 

·
Registered
Joined
·
1,652 Posts
Discussion Starter #19 (Edited)
when you say gte are you meaning 7mgte...my concern with that statement is cps...???

however this is a huge break threw! maybe someday it'll be a popular option among the community!
Yes, 7MGTE, if you look inside the CPS of the GTE and the dist of the GE you will see they look identical. So there should be no issues with using the GE dist for a CPS. The 7M dist and the CPS do not fit because of the fuel rail and the only way around that is to do the simple mod to the 5/6M dist.

Shawn: Gap on the 5M electronics was .080

Mark: Piggyback will be a MAFT Pro which should go in this weekend. It has the ability to do fuel and timing.

Although the install and proof of concept is done there is still a lot playing around to do.
 
1 - 20 of 117 Posts
Top