enough injector????

[sdteb]

going for 9's

current setup
83 lb inj flow matched from racetronix
champion alum heads
scorpion roller rockers 1.65
215/220 hyd roller
cat/eagle crank
champion intake and doghouse
70 mm accufab tb
RJC pulleys
k1 rods
70 gtq dbb
turbo 400
ptc converter (dusty bradford)
liquid intercooler
distributor setup
fast xfi
using c16
Aeromotive 11104 - Aeromotive Eliminator Fuel Pump
etc etc

do i need to need to upgrade to 120 lb inj???

Racetronix-INJL120FM Injector

 

[87NAT]

Theres a few guys running 9's with 60# inj and less turbo. I would think you would be okay but you have to determine that by some real time data. Your A/F and duty cycle% will tell the whole story.

 

[Chuck Leeper]

Hi 9's compares to approx 138mph, if all is right.
138 mph in a car I assume is approx 3700#, requires a RWHP of approx 760. [FWHP estimated at 850].
To make 850FWHP, at a BSFC of .6, and a duty cycle of 85%, calculates to need a 100# inj.
FWIW, I ran 141+ at hi 9's, 3710#, with 95PPH injs. I had an average EGT of 1600*F at the base of the turbo. A/F was 11.5.

I'd keep a real close eye on the plugs..Here's a way to do that.
sparkplugreading
9's on 60# injs?? Must of used ALOT of methanol to do that, and stay alive.

 

[Cme2fly]

Theres a few guys running 9's with 60# inj and less turbo. I would think you would be okay but you have to determine that by some real time data. Your A/F and duty cycle% will tell the whole story.

Not without running alcohol injection..

 

[87NAT]

Hi 9's compares to approx 138mph, if all is right.
138 mph in a car I assume is approx 3700#, requires a RWHP of approx 760. [FWHP estimated at 850].
To make 850FWHP, at a BSFC of .6, and a duty cycle of 85%, calculates to need a 100# inj.
FWIW, I ran 141+ at hi 9's, 3710#, with 95PPH injs. I had an average EGT of 1600*F at the base of the turbo. A/F was 11.5.

I'd keep a real close eye on the plugs..Here's a way to do that.
spark plug reading switch champion at sparkplugreading
9's on 60# injs?? Must of used ALOT of methanol to do that, and stay alive.

If I am not mistaken Grumpy is running 60's. But you are right Chuck...he is probably spraying about 3 gallons of meth per run.

 

[87NAT]

By the way Chuck that link to Sparkplug reading by Larry Meaux is very good. He actually lives about 5 miles from my house. He has a small shop and does killer headwork for people all over the country. I have been there on many occasions for engine dynos. Larry knows his stuff and considered by everyone around my community as the smartest guy in racing.

 

[johnplogii]

Not in the nines yet but pretty close with 60lb injectors & NO meth. FWIW the mototrons actually flow 65pph from what I've heard.

 

[sdteb]

FAST PRECISION-FLOW FUEL INJECTORS FOR 4, 6, & 8 CYLINDERS

 

[Racetronix]

Not in the nines yet but pretty close with 60lb injectors & NO meth. FWIW the mototrons actually flow 65pph from what I've heard.

Siemens spec is 60.56lb/hr (+/-6%) with test solvent. You can add apx. 3.5% to that when using gas. That is pretty much the rule with most manufacture spec.'d flow rates.

Racetronix-Siemens_Injector_Sale-55h

 

[RUQWKNF]

Here's my O2s worth.
I used to go through this with customers all the time back when I was at PTE. On my old '86 T-Type, (TSE setup) 274 CI Off Center Stage II, GN-1s, 224/224 flat tappet, PT74 GT-Q 3 bolt .85 A/R turbo blah blah blah, I ran 84# Delphi injectors with a Weldon DB2015a pump, -10 AN feed line, external regulator, -8 return line all the way back to the top of a stock sumped tank. When the car was running consistent 10.ohs to 10.teens at 134-135, I was seeing between 78 & 79% injector duty cycle running an old Sequential FAST system. My A/Fs were 11.3 with correction factors on all runs within +/- 2%. Very safe tune. Boost was up there tho with that baby cam. Typically between 29-32.

84# Delphi injectors will support 1008 flywheel hp safely when coupled with the correct fuel pump and EMS system. 83#ers will support 996 flywheel safely as well. With all the formulas out there, my car was making somewhere between 740-745 rear wheel hp to run the numbers it did at it's 3670# race weight. Now, if you throw another 50 rear wheel hp at that combo, it would have been running consistant high 9's. Even at that, 84#ers would have been enough. The car did run one 9.90 pass at 129 blowing a head gasket back in '03 with my hot shoe driver Dave Fiscus behind the wheel. That pass would have been somewhere in the 9.70s if it would have held. The gasket blew out just past the 1000ft mark and Dave lifted shortly there after. But oh well, I digress....

The real trick is to get your race weight down, so that you don't have to have as much hp to run the number. IOW, you won't have to kill the turbo or motor with super high psi to run a number. Just look at the TSM guys and what they have accomplished in the past 2 years. Stroker motors help big time as well. 120-160# injectors are way over kill for a mid 9 second Turbo Buick. Driveability is terrible with 160s.
Hope some of this helps.

Patrick