Dyno today!

[blown69nova]

I'm finally going to see what kind of power the car is making, wish me luck!
Anyone care to predict? My setup is:
383 sbc gen1
8 to 1
TFS 195cc heads as cast, cnc chambers
224/236 dur., .573/.593 lift, 116 lsa hyd roller cam
Motown single plane, converted to efi w/ custom elbow and 75mm t/b (Ford), 55lb primary inj. with 72lb secondary inj. (4 of them)
Electromotive Tec2 ecu
1-3/4 long tube headers, 3" exhaust w/x-pipe, Borla's and dumps
Procharger D1SC, 18lbs (so far) boost, custom air/water intercooler
Th400, Prec. Ind. 3,000 stall, 9" rear w/ 3.73 gears.
Did I leave anything out?
I will let you guys know later today, thanks for looking.
Steve

[Steve68]

Got Pics????

[blown69nova]

Well guys it made 520/505 hp/tq on 7 cylinders! Very long story, bottom line is, I can't control fuel properly and the ignition system is erratic. All of the plugs look different.
On the drive home the car was missing and sounded like an exhaust leak or something, so when we got home we did a comp. test and all but #6 had 150psi, which had 45! We then did a leak down and it held fine, so we thought bent rod, but when I pulled the rocker cover #6 intake arm was off. The pushrod was nice and straight, so I lashed it down and it cranked at 150psi, WHEW! That is where I'm at now, so time to sit back and figure what to do next about my injection system.
Thanks for reading, Steve

[camcojb]

Well guys it made 520/505 hp/tq on 7 cylinders! Very long story, bottom line is, I can't control fuel properly and the ignition system is erratic. All of the plugs look different.
On the drive home the car was missing and sounded like an exhaust leak or something, so when we got home we did a comp. test and all but #6 had 150psi, which had 45! We then did a leak down and it held fine, so we thought bent rod, but when I pulled the rocker cover #6 intake arm was off. The pushrod was nice and straight, so I lashed it down and it cranked at 150psi, WHEW! That is where I'm at now, so time to sit back and figure what to do next about my injection system.
Thanks for reading, Steve

Can you explain the injector deal? Never heard of a primary and secondary injector unless it was injectors per cylinder.

That EFI system is not a big friend of mine, very clunky to tune in my opinion. Hopefully the tuner is familiar with it and can sort it out.

Jody

[blown69nova]

A good friend of mine, and myself have been doing the tuning.
I can't fuel this thing properly on BOTH top and bottom with a phased seq. control.
I can run as big an injector they make for wot power, but I can't control them for cruise/idle- way too rich!
I run eight 55lb inj.'s for normal operation, but run out of fuel by 5000 rpm and maybe 10psi. boost.
My ecu has only 4 drivers for injectors, but has a GPO output that is a pull to ground circuit you can use to trigger a relay between 16 and 212 hz. Of course, a standard relay cannot switch this quickly, so I use a solid state relay. The injectors do turn on, and I can control the duty cycle in my GPO map/rpm table- or so I thought. Yesterday on the dyno, after the first pull, we were looking at the logs on my wideband and ecu with the key on, and somehow the injectors turned on, filled the cylinders and the engine hydrolocked! This never happened before of course, we thought we had it working properly and that is why we thought it was ready to tune on the dyno. Needless to say I need a new ecu before I blow this thing up!
Steve

[camcojb]

definitely dump that system and get something that can properly control 8 injectors. I've run 95#ers with perfect idle characteristics with the FAST and Accel systems.

Jody

[blown69nova]

I talked to a Electromotive dealer today and the guy told me my 55lb injectors should be more than enough to feed my power level, what do you guys think? My setup should be in the 700+ hp range (crank) with 18+ psi boost I would think.
I am going to try my buddies spare Tec3 ecu since I have the ign. setup already. This system is sequential so it will be able to control it fine.
Steve

[Blown353]

No way will 55's make it.

I was maxing my 55# injectors at about 5200rpm with my smaller 353, no intercooler (so comparatively worse air density than your setup) and less boost. I now run 75# injectors and have seen a max DC in the 82% range. I can't see 55# injectors being adequate for your setup.

I'd run 75 or 83 lb/hr injectors for your application.

[blown69nova]

I thought 55lb's seemed kinda small. Thanks for your input.
Steve

[Fuelie Fan]

Umm, there should be no mystery. Look at your log charts. Do you go lean on the top end? What's your max duty cycle? I'd use the data to determine whether you need new injectors.

[blown69nova]

My duty cycle was 88% at the top end, and still going to 14:1+ afr.
The mystery is my plugs, they are all over the place in color. Cranking pressure and leakdown is fine. I think I have an ignition or injector firing problem, some of the plugs are sooty black and some look almost new. The strange thing is, they are not companion cylinders (waste spark/phase sequential strategy).
Steve

[64duece]

Sounds like you have some serious issues there. Remember your averaging you O2 from 4 cylinders (some fat/some lean) don't expect to trust that.

Get those cylinders running closer, then you can begin to fuel accordingly. Those 55's are good for 650hp at 90% DC and BSFC of .60.

[blown69nova]

Yeah, going to check the injectors.
I did just purchase a Tec3, so the wiring and coils will be new. I will see if the new setup helps, if not, I will continue to diagnose from there.
Steve

[speedster]

For base runs at NRE, the setup was a TEC3 controller, 83lb injectors and a F-2 blower with absolutely no problem from idle to WOT. 83's can support 1000+ hp with various combinations.