Jameslt1TA

Awesome work man! Are you just running one walbro? Thats what I'm running and I'm pretty sure it is running out of fuel and the pump is getting really tired of being overworked. It ran fine for quite awhile, but suddenly it starts cutting out at 5000k in 4th gear which is the only gear I will get traction and reach full boost(14 psi). If I let off the throttle then floor it again the pump catches up and it will run fine up to 6k rpm limit.

Should be getting in two walbros, hobbs switch and everything I need to make my dual kit in next week. I should probably get a fuel pressure gauge also. If you are only running one pump it will be fine for awhile but they seem to start not pushing enough pressure. After 10 mins of driving my voltage drops from 13-14 to 11-12...I'm guessing because the pump is worn out and drawing to much.

MikeGyver

Hey thanks. My fuel pressure is dropping to 30psi above 4500rpm as u can see in the dyno graph. I'm also going to put a 2nd walbro in on a hobbs switch.

A few days ago I ran some quick numbers to see about how much HP my walbro should support.
Below is the graph for my pump.

so at 53 psi (43.5 + ~9psi boost) my Walbro GSS340 flows about 53gallons per hour. I'm assuming this test was done at 13.5v, which I'm sure is more than my pump is getting, so we'll just say 50gph, which is still high.
Gasoline weighs about 6.3lbs per gallon. so that's a flow rate of 50x6.3=315lb/hr.
BSFC (brake specific fuel consumption) for a turbocharged engine is typically .6 lbs per hour per hp or higher, so enough fuel to produce somewhere around 315/.6= 525 uncorrected flywheel hp which is very close to what my engine made disregarding the dyno's elevation correction. As fuel pressure dropped, flow went up till it stabilized around 30psi....
....I guess this is just a long way of saying I definitely need a second fuel pump

blown94

im facing the same dilema as we speak, right at 10 psi above 4500rpm approx. in 3rd gear (auto). So it looks as if we have 4 similar cases (that ive read about in the last month), and all seem to be around the same power level. I bought my 2nd walbro and a 200 psi meth pump to upgrade my 150 psi pump, along with a 2nd injector for the meth kit so I can tee off and run 2 nozzles. That should cure the fueling issue. Ive read numerous times that FI require more fuel than NA and these gss340's are only good for a tad over 500 FI.

On a side note, I wish you lived closer to me, so I could have you plumb an intercooler for my TA, lol. Because you sure do nice work. I love build threads, great ideas get tossed around, and its great motivation, especially since my 383 shortblock is done and I need to make some changes in my layouts and add some stuff. Thinking about adding a stand alone fuel system for the wet plate kit, but wondering if the big shot of meth will suffice if I pull 6* timing.

RalphBoggero

very nice job Mike Gyver what kind of pump u use to return the oil from the turbo?
u take oil from the engine or is a closed circuit, and thinking to build mine with a close circuit with a radiator , what do u recomend?? best regards

MikeGyver

It's just the normal STS oiling system. I would have the engine feed the turbo since it's basically 'free' and much more reliable than an electric pump.
You'd have to use a very serious electric oil pump to feed ~30psi at decent flow reliably for a long period of time.
Either way would use an electric pump, but I see no benefit at all from using a high pressure pump to feed the turbo, as opposed to the sts system that just throws 'loose' oil back to the engine.

MikeGyver

Got the pipes back from ceramic coating about a week ago...




Exhaust piping done in black ceramic.


Hidden on the backside of the pipe is: an adjustable Hobbs switch for triggering 2nd fuel pump under boost, the wastegate reference port, and an extra port just incase.

RealQuick

Looks good!

How come the black ceramic coating isn't on the inside of the pipes?

MikeGyver

I think the black is a top coat on the (unpolished) silver, it's technically a heat barrier coating.

wite97z28

this build is awesome!! the car sounds sweet, and all the welding is great. a good skill to have. i would like to do this to my car in the future but im a college student and dont have the money right now, lol. it would be nice to see that car run at the track.

what kind of gearing does the car have? 3.23?... 3.73?... 4.11?

MikeGyver

Hey thanks. Ive been a part time college student with a part time job the past couple years... and I've managed to make things happen, albeit slowly.

The car's suspension, brakes, and drivetrain are stock, 3.23 gears I believe.
It's not set up as a track car in any way really, It needs a ~3500 stall converter so I can actually launch with boost, or some sort of ignition timing retard setup or something.

wite97z28

go with the stall converter. check on summits website, they should have some good ones. and once you upgrade your suspension and drivetrain your car will really take off

Camride

I hadn't read your build thread until now and I have to say: Nice fabrication, beautiful welds. Also, gotta love the stock ported manifolds (I did this on my old '94 Z28, I was surprised how much of a gain I got out of doing that).

Great job man.

MikeGyver

Selling my 60-1 turbo if anyones interested https://www.camaroz28.com/forums/sho...26#post6615026

DirtyDaveW

Moving off to another size Turbo or getting out of F.I.? Looks brand new.
The weather here is teasing us with the odd 50 or 60 degree day, though it's back to 30's today with a little snow. The freakin wind has blown off my car cover twice but I have to admit, as I walk out to recover it, it makes me grin when I see it all waxed and shiiney, ready to be driven soon.

MikeGyver

This is my original turbo, I just need a bigger one to hit my power goal.