Thread: 350 Chev with FAST EFI

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Hello everybody.
Need some help here. Had a (professional) engine and rod shop build a 1967 350 Chev engine. FAST 30227 kit, OP Cam Lifter Kit sb Chev hyd rir, not much more info from the build sheet. But I can send it if you need it to provide an opinion here.
Got the car and it runs very poorly. Burns so rich your eyes burn. No power, and very rough.
The FAST is supposed to learn but it hasnt get any better. Two shops have looked at it but neither seem to have anything to offer.
I am sure some of you out there know what to do and are experienced with the FAST or what might be going on here.
To be clear it seems moderately ok at times. Ran it across the USA and Canada last summer. But eyes burn and the smell is terribly rich.
Any thoughts out there?

thanks.
Ken and Axl

How big of a cam is in the car? Too big of a cam confuses the ECU. Have you called the techs at FAST about it?

Good question on the cam size.
Wasnt supposed to be much when i ordered it and it sounds pretty mild.
Things did not go well with the shop that built it to say the least and the build sheet does not show a cam size or numbers.
I havent called the FAST guys yet. I assumed that the shops would figure it out but i will call them tomorrow and get their thoughts.

Not familiar with the Fast system in particular, but with other brands that I've used you still need to tell the system what A/F ratio you want to see under 4-5 load conditions. it will self tune from there, but needs the basic information to get things started. most will have those A/F ratios set very rich to begin with, so if you decide to start the engine before setting it up correctly you won't blow it up lean. ck your Fast owners manual. if you don't have one I suspect it's downloadable on-line.

Russ

Russ;
Thank you sir.
That could very well be it.
I don't think it was ever set properly from the get go.
I will download the owners manual and get into it.
To be honest I chose the efi because im not very good with engines and carburetors.
But I have been assembling the 427 BBC and plan to get into the efi, or put a carb on it over the winter.
But I will be into the manual tonight for sure.

Thanks again.

I've been researching the FAST system for a project I'm working on. Seems that some of the controls in the setup software will allow you to go to negative settings. This apparently is not very well documented in the manual.

At least one person I read about had a rich idle problem that actually caused flooding and stalls. The control for idle mixture was set to "0" and it was still rich. By accident he discovered that the control would actually go below "0" and that cured the problem.

Dave;
The Cam is a Comp Cam 12-432-8

Hydraulic roller tappet
Basic Operating RPM Range:2,200-5,800
Intake Duration at 050 inch Lift:230
Exhaust Duration at 050 inch Lift:236
Duration at 050 inch Lift:230 int./236 exh.
Advertised Intake Duration:282
Advertised Exhaust Duration:288
Advertised Duration:282 int./288 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.510 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.520 in.
Valve Lift with Factory Rocker Arm Ratio:0.510 int./0.520 exh.
Lobe Separation (degrees):110

Found these specs for the cam, lots of duration for a street cam, might want to ask FAST when you talk to them if the cam is creating some problems that need to be addressed in the ECU....

True. if the vacuum is too low with that cam the ecu thinks the engine in under more load than it actually is, and dumps in more fuel.

OP. how much manifold vacuum do you have at idle and cruise conditions?
Also, Is the MAP sensor built into the TB on that system, or plumbed into the manifold somewhere with vacuum hose??

Russ

Thanks for the help to everyone.
Talked with FAST for a couple of hours and we seem to have solved most, if not all, of the issues.
First there was the vacuum line also hooked up to the pcv via tying it together with a T fitting and to the master cylinder.
so there wasn't enough vacuum to do it all. So we fixed that.
Second the shop had the iac setting at 3-4. it needed to be at 20 or so. This left the system starving for air.
tuned up the adjustment and got it to operating temperature and it seems to run very very well now.
No eye burn and way better power and performance all around.
It did run a long time (5500 miles) like that so I will change the plugs and see if that further improves things as well.
in regards to the cam I may change it over the winter to more of a stock cam. The Camaro is just about fully stock with the exception of the cam, chrome alternator, power steering pump, and electric fan. I may put things back to more on the stock side as I really intended it to be.
Great help from all of you. It sounds stupid but I hadn't thought to call FAST after the shops looked at it for some reason. But they were very helpful and professional.

Really good to hear you got it sorted out, probably make the cruizin' a whole lot more fun now!!!!

X2 on Dave's message. Too often we run down rabbit trails assuming that everything done before us was done right or searching for an "expert", neglecting to go back to the guys who know their product backwards & forwards. Even more critical with today's electronics, IMO.