[bftsupra]

I am having a problem with fuel not fully burning. I was on the dyno and a large black cloud of unburned fuel starts blowing out at about 5k rpms. It was obvious to the dyno boys and myself that it was fuel, as it reeked of gasoline.
They suggested closer gapped new plugs, change the fuel filter, and maybe buy an MSD. I put autolite coppers at .29, seemed a little better, still see the cloud. Replaced the fuel filter and installed a new set of NGK wires. It is still doing it and obviously not reaching its potential.
As to the MSD, I was looking at the msd 6al with the limit set to 7k so I don't destroy this puppy accidentally. At this point they tried to sell me the BTM model which retards the spark according to boost. It says you can retard up to 15 degrees at a rate of 1-3 degrees per # of boost. I am currently running ok at 15 -18 # and this sounds like way too much retard to be of use. I am not inclined to spend that much cash anyway, but wasn't going to worry about retarding untill I am running 20+.
1. Has anyone used one of these? Any recommendations on any MSD?
2. Is my bosch BOV up to this? It may be giving up at this level also. Anyone running high boost on one of these?

I think I should be seeing somewhere near 400 hp if it works right. I won't really get the car tuned until I can sort this out, and don't want to spend too many hours at $100 per just doing the basics.

 

[SoupedUpSupra]

considering the mods you already have, i think it is time to upgrade your BOV.

 

[ma71supraturbo]

you tried leaning the mixture? what is the a/f ratio like?

 

[Guest]

You need to DEFINITLY be-rid of the Bosch BOV, which leaks a ton of air at idle throttle. If you are strapped for cash, may I suggest the mod I just done to my car:

Link:

http://www.supraforums.com/forum/showthread.php?threadid=163185

If you have the money for a $200+ aftermarket valve, then your best bet would be to opt for a quality valve like the HKS SSQ, Tial, or GReddy Type-S.

 

[Supra_N2O]

i have the type s...i hate the ghey little chirp that the ssqv outputs. the S is a nice long hissing, sounds mean..and can be had for like $180 on ebay

 

[DLC]

considering the mods you already have, i think it is time to upgrade your BOV.

It depends on which Bosch BOV he has. The Porsche spec BOV will handle lots of boost. I have one on mine and have never had any problems even at 20 lbs.

 

[Ckanderson]

20 psi? ha not for long, mine didnt handle 12 psi for very long....

 

[DLC]

20 psi? ha not for long, mine didnt handle 12 psi for very long....

11 months @ 18 lbs. with no problems. Was yours a Porsche spec? The Saab spec Bosch BOVs are only good up to about 16.

 

[Ckanderson]

better have been porshe spec, i bought it from them....but ya, my diaphram ripped.... that sucked....

 

[Guest]

don't waste your money on a 6al, get a DIS4 if anything, you can adjust the timing you want at which rpm, and no timing retard at all if you don't want any...

seems there might be a problem with the 7mgte and the DIS4...

I burned up a tach adapter within 30 minutes of the install, sent it back and i'm waiting on another one... I talked to a fellow mkiii owner who burned up 4 tach adapters and eventually gave up... if i burn up my next one i'll give MSD tech support a call

 

[AWIDESUPIE]

The Bosch BOV/BPV that handles ~20+ psi is both Saab and Porsche and Audi valve. The only importance is the last three numbers in the PN for the Bosch valve ... not many people realize this though.

The "110" or true Bosch PN: 0 280 142 110 is the valve that will hold 20+ psi. It has done so before and no problems have been reported by anyone who uses the 110 at these boost levels on smaller turbos(ct26/t3/t4/to4s). The 110 does not make the "hoot" sound at idle either.

See:
http://www.supraforums.com/forum/showthread.php?s=&threadid=72552&highlight=BOSCH+BOV

I have driven a 400+hp supra running modified ct26 at ~20psi and the 110 did very well. No surging .. and a lot of noise at that boost level .. even with it routed back to the accordian hose.

 

[williamb82]

the msd 6al wont work for the 7mgte unless its just a turboed n/a. the 6al wont work on multi coil systems. get the dis 4. as for the bov leaking, cant you just flip it around so the boost will hold the valve closed till you let off like the hks ssqv instead of trying to push it open all the time like the type s? thats what id try if it were me.
william

 

[bftsupra]

What I love about this forum is, you can usually get someone to agree with what u think if you get enough posts. Not that it will be true or correct, but there are a wide variety of opinions available.
1. MSD 6al won't work,,,, kk
2. DIS4 is the way to go,,, but it won't work... hmm? NE1 got one working right?
3. Type 110 BOV , which I have, should be fine or won't work...well it makes a sick goose kinda honking noise under light boost at about 3k rpm, but seems ok otherwise, i can boost 20# with it, but amy i working the Turbo to death?.
4. Lean it out,,, well I ran 10 dyno runs, and they thought I should richen it up, as it was near stoich when I started and we stopped each run as it got lean. I had just popped the Lex AFM on that day, so I epected it ot be alittle off. It is pig rich now, but as I said, I wanna feel sorted out before I splash more cash on it at the dyno. I had it set near 12, they liked it near 13, but said we could lean it some when we got smooth runs to desired top end., ran outa time and had the problem with blowing spark out.

 

[AWIDESUPIE]

TRD91 is running the MSDDIS4 with 2-step etc .. perfectly.

110 BPV/BOV should and does defintely work for 20lbs on modified ct26s as to4s/t3s/t4s etc ... should also work for your full to4. Try it and you'll find out .. no biggie .. especially if you already have it. Only ~30$ down the toilet if it breaks. If you would read the thread link from my first post in this thread .. and then read all the test links in that thread ... you should clearly see that the 110 is superior to all and should definitely hold 20+lbs. There ae several users, who's names I cannot currently remember, that run over 20psi on the 110.

A/F gets complicated via rpm ranges etc. Not my area of expertise, currently.

Best regards.HTH.