Hi all,

I just got my project car running/driving last night. Currently I'm running no emissions and a straight through exhaust (2.25" DP and mid-pipe w/3" single pipe out the rear), rebuilt stock turbo with a pretty mild wastegate port. I've got some GSL-SE injectors in the secondaries because I'm planning on running 10-11psi boost.

Current power mods are:

680cc/min secondaries
550 primaries
Straight through exhaust
RB FCD
Stock intake with K+N drop-in

With the above mods the car starts missing after 6000rpm and I have to shift, this really cuts down on the useable power. Are the secondaries choking it, it seems like it?

Planning on:
TID mod
Manual boost controller adjust boost to 10-11 psi

Jeff

93 R1
87 TII 2660lbs
Other mods
17 lb flywheel
ACT clutch
FD disc
Eibach springs
RB sway bars
225/50/16 Kuhmo Victoracers

 

I would think those injectors should be fine for the mods you mention... if anything maybe a little on the low side.

But first I would be looking at two things:

What condition are your plugs and plug wires... factory Mazda plug wires are usually mis-fireing pretty bad by the time they have over 60K miles on them... it will be much more apparent at higher RPMs.

If you drop the 550s back in does that solve the issue?

 

I was thinking plugs/wires too, but some people over look the fuel filter...Just a thought?
Good luck.

 

hmm Hey is it a 87-n-half? I forgot how to check
but I read somewhere you need some kind of resister
on cars above 87 n half for them to work properly

 

KABOOSKI, check this out..http://www.k2rd.com/FC3S/MODS/FUEL/inj.htm and TurboJeff if you do not like the 680's give me a call and rid yourself of those injectors. Always happy to help out.

 

Ok, here's an update...

I did a little testing on Friday afternoon. I installed the boost gauge and found with the ported wastegate I was only getting 5.5psi in 1st gear and 7psi in 2nd and 3rd. At those boost levels I didn't even need an FCD, so with the ECU firing the 680cc injectors (thinking they are 550's) it was running rich for sure.
The symptom was the car would start mis-firing at about 5500rpm in first and about 6000-6200 rpm in 2nd and 3rd.

So Sunday afternoon I installed a brand new, in the box, 13yr old HKS manual boost controller. I tinkered with it for just a little tonight and with the boost adjusted to 8-10psi (goes to 10psi then back to 8psi) this mis-firing occured at a little higher rpm, 6500+. Adjusted for a little more boost 9-11psi and it mis-fired even less. The g-tech gives me a 14.7 as my best 1/4 mile time which is disappointing to say the least since I ran the same time with a different 87 TII with only a HKS cat-back and a K+N drop in filter, this car weighs about 200lbs less and doesn't have the cats on it.

So now my question is, what is about the safe level of boost I can run with the stock IC and the 680cc/min in the secondaries and a FD fuel pump (not installed yet)?

Can anyone give me a cheap source for a K+N style cone filter that will fit on the end of a MAF adapter?

Anyone have a cheap electronic boost controller for sale?

Thanks,
Jeff

 

OK, looks like this thread might be dead but I figured I'd give an update.

I took out the 680's and put the 550's back in. Results are amazing, the car really rips through the gears now. I'm running about 7-8psi boost and I've turned a 13.92 sec 1/4 mile on the g-tech! The 680's are just too big to be run without a SAFC or something.

The wierd boost problems with the manual controller were caused by the boost rising nicely before the secondaries staged. When the secondaries came on it would run too rich and lower the EGT cause boost to fall dramatically. I'm sure it was running way lean on the primaries and rich as hell on the secondaries.

Anyway I'm in the 13's with just a open exhaust and a ACT clutch w/17lb flywheel, yeah!

Jeff

87TII 13.92 (g-tech) 2640lbs

93 R1 13.59@102.85 (on the strip) 2800lbs

 

Cool, thanks for letting us know what happend