Blacktop 20v Fuel Upgrades

[mandm177]

Just from my personal setup and a general FYI to everyone. These are currently running on my car.

Fuel Pressure Regulator: AEM FPR from a 92-96 Honda Prelude. Mounting holes need to be bored out a tiny bit.
Fuel Injectors: 1JZ Yellow Top Side Feed 380cc Injectors
Fuel Pump: 7MGTE from Mk III Supra

[dr.occa]

Have you experienced any benefits from going with the larger injectors Mark?

It doesn't run rich at all?

[mandm177]

not yet...I have the bigger injectors, but have the pressure turned down slightly (from what i remember...i'm at work right now), but no popping or shooting flames or anything like that out of the ordinary. lol.

According to the butt dyno, my midrange does feel a tad bit stronger than before though and that puts a smile on my face.

I think we've talked about this, but just as a refresher:
My quest for fuel upgrades started when my car would bog at WOT at 7000 rpm. When i had my individual uni filters and trumpets on, i was able to rev freely all the way up to 8k, but when i ran open stacks, i was no longer able to. Thus, i thought i was running lean up top (more air than before) and decided to do mods to increase the amount of fuel. Well, that was a couple of years back, and i just sort of put it on the back burner.

Well, recently, i've had a reason to get it sorted, so i tried a couple of things...read up on 9000rpm.co.nz about bigger injectors, and Aaron had a contact that had a set for sale, and for the price, i thought it was a worthwhile experiment. Did it, and nadda, BUT my midrange did feel alot better. Still stuck at 7k.

Read up a bit more on 9000rpm, and read up on some folks who have been using colder plugs with success, so i decided to try that. It was time for a "tune up" anyways and again, for the price, it was worth the experiment, i bought some regular, copper NGK BCPR7ES (1 step colder than stock) and put these in my car. Well lo and behold i'm now able to rev all the way up to 8k once again!

I'm going to put my stock injectors back in once i get some new "injector insulators" from Toyota and see how the car runs to see if there's any difference between the two injectors at the same fuel pressure.

I'll probably pull my plugs after a good week of driving around and see what they look like. My old plugs were white and pitted as could be.

[mandm177]

FYI: I don't condone the way i went about doing this...throwing parts at the car hoping something will fix it is NOT the way to do something. lol.

[dr.occa]

In my old age I'm not surprised I forgot if we discussed this topic already. IIRC the 20v fuel system tends to putter out (possibly even the 16v as well). I think McKenney and I also talked a little bit on this and that by richening up the fuel a tad bit the 4ag does pep up in the mids which then carries it on over to the higher rpm regions with better stability. Thanks for bringing this back up Mark.

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[McKenney]

yes but that is only on the afm motors. Mine is tuned rich and is usually ok, I need to change plugs though! btw the mk3 Supra and gts corolla use the same pump stock. In fact the turbo and non-turbo 7m Supras both use the same pump stock. Remember I work in a parts store!

[dr.occa]

...Remember I work in a parts store!

last 2 weeks?

[McKenney]

going part time here, gotta keep that hella discount man!