need fuel injection expert / dallas area

[Rick Orsini]

Well, after several weeks and two tow truck trips back to the house, I'm officially throwing in the towel. I give up. I can't get this combination to work right and need the assistance of a local custom fuel injection guru. I would appreciate any assistance in locating someone to help restore my confidence in my cobra.

Combination is:

1991 5.0L engine
Scorpion roller rockers
Stack EFI intake
SDS custom programmable computer
MSD 6A

Thank you,
Rick

[4RE KLR]

Rick

The best 5.0 guy Including fuel injection I know of is a place on Loop 12. The name of the place is Lone Star Mustang (?). I think the exit is Singleton off of Loop 12.

LoneStar
5.0 Repair & Performance
Brian Porter
214-630-5006
214-637-0430 Fax

2511 N. Walton Walker,
Dallas, Texas 75212


These guys seriously Race the 5.0 mustangs and do VERY WELL on the track. They are also NOS experts on these (5.0) cars. They are nice to deal with and very helpfull. They have a nice shop and all the tools and can also get the baby botle filled (NOS) onsight. I met these guys from workinh with my Nitros system.

I have not been over to the shop in a year or so, so they won't remember me, but that should not concern you. They know thier stuff.

[427Aggie]

Sometimes I think the webers were easier

Rick you are going to have some of the same problems as webers with that fuel injection.
WHats going on?
WHat size cam do you have in that car?

Matt

[JBAIRD]

Steve, I beg to differ with you onthe fact that they know their stuff. We have 2 cars in our shop that Lone Star gimpped up with their lousy workmanship last week. It's the last place in Dallas I would reccommend.

[JRoss]

Rick,

Contact Bob Norwood, he is a fuel injection and a weber guru. Sorry I don't have his number anymore but he should be listed. I think his new shop is in Garland somewhere.

John

[Rick Orsini]

Thanks for the advice guys, I'm just a little frustrated with the way this thing has been going. It's been one step forward and two steps back during this whole upgrade.

Steve, thanks for the recommend on Lone Star. I have used them for my Mustang and have been pleased, though I have heard problems reported by others.

Matt, it's a pretty stock setup, standard 91 5.0L block with stock cam and heads. I've got roller rockers on it, but other than the new intake, computer, fuel and ignition, it's pretty much stock. It probably would have been easier (and cheaper) to go with the Webers, but at this point I'm a little too far down the road.

The latest problem I've been having is that it runs fine for a while, then starves itself off (like it's running out of gas) and won't start. The last time it ran, I was idling it in my driveway and it ran fine. I let it sit until it got up to about 175 degrees, then took it around the block. I got one street away and it stalled out and I had to push it home.

John, I tracked down Bob at his shop in Garland and left a couple of messages, no reply from him. I'm sure he's really busy with the race cars.

- Rick

[Cobra #42]

Rick, I didn't want to say anything bad about a shop, but Drew is dead on. Lone Star kept Bob Norwood very busy when he was in Irving with cars from Lone Star after they would give up, or screw up so bad.

Bob is the man !!! Unfortunately he is usually covered up with high dollar race cars, you know money talks and BS walks. Sorry to here about your problems. db

[427Aggie]

Rick who's setup did you got with? I ask because Richard Price had an imagination setup on his 460 in Tulsa and it had the same problem...when he would sit there he had to keep his foot on the gas to keep the freakin thing running.

Matt

[Alan Schup]

I have gotten the Holley Projection to work ok on my Cobra, though I am still tinkering with it. The acceleration is instantaneous compared to the standard carb I had --- I like it. I wish there was a professional shop that knows more than I do, and I know very little. I might ask those LoneStar Mustang folks if they can help me out and educate me.

The problem with the Holley system is that the O2 sensor needs to be as close to the engine as possible to be in the hottest exhaust as possible --- Holley tech says no further than 14 inches. But doing so, one can only monitor the O2 on only one cylinder. I found though this is not ideal, it is better than nothing. Further than 14 inches, the engine will way run too rich all the time. I essentually have the "MAP" close for my engine, and still figuring out all the various the adjustments for acceleration. I have my injection setup where it uses the O2 sensor closed-loop for city cruisin' and open loop for racing/passing (using RPM and throttle position). I've been using AutoChart software instead of Holley's (http://autochart.com/)...

Good Luck,
Alan

[Cobra Dude]

Rick,

One of the biggest problems with Cobras and EFI is the placement of the O2 sensors. They need to be a certain distance from the exhaust ports from the heads, and need to be hot -- even if they have internal heaters.

Is the SDS your ECU? Or are you running a Ford ECU such as an A9L or other EEC-IV-type processor. If a Ford ECU, I can recommend a guy at Dallas Mustang who's known as a guru (I'll need to dig up the name/info), but if not, then you may have to deal with the SDS folks.

Assuming that the SDS is the ECU, what are you using to tune it? Does it have any output capability so you can see if it's rich or lean, timing values, etc? If you do, that should tell you which direction to adjust towards. You could also get a lot of this info from a Dyno shop. Another option is to get a wideband A/F gauge ... don't waste your money on anything that says it'll work off a stock switching O2 sensor.

Another place to check for info is www.diy-efi.org. You'll find tons of good info on their site, though I know that their server has been down for the past few weeks.

Either way, post some more detailed info on your setup and I might be able to save you from the tuning hassles I had in the early days.

Cheers,
-Neil.

[JRoss]

Rick,

I just talked to Ernie at ET Automotive in Garland. He has installed one of Wayne Presley's injection setups on a car and is in the process of putting a second one on a Cobra. The motor is supposed to go on the dyno this week. Maybe he can help?

John

[Rick Orsini]

That would be great John, it would be good to talk to someone else local who has done the install of this setup and tuned it. If you've got a number, please forward it to me at rickorsini@yahoo.com.

Thanks,
Rick

[Rick Orsini]

Neil,

Thanks for the response. I'm running the SDS computer setup with custom wiring. The computer is running open loop with no O2 sensors. The intake is a custom stack EFI and the rest of the motor is pretty stock 1991 5.0. The only other performance mod is roller rockers. I just downgraded the injectors from 24lb back to 19lb as is was running really hot. I had been running the standard EEC IV setup with a Cobra intake before the upgrade and that ran fine.

Today I went back through it and reset the base timing on the engine and the computer and re-entered all of the default values for the computer. I was able to get it started and running, though it still runs rough. I took it around the block a couple of times, but am still apprehensive about taking it any distance. Once I'm sure it'll stay running and get me home each time, I'm going to take it to a dyno to tune it. I've got a lean/rich meter that is hooked up and I've been using that to tune air/fuel at different RPM levels.

I'm sure once I get it on the dyno, I'll be able to get this thing dialed in. Thanks for the additional info.

- Rick

[JRoss]

Rick,

You have mail

John

[392cobra]

Rick,
Hasn't been any updates from you.
Have you got the problems worked out and got it back on the road ???

[fubar]

I just had Norwood put a stack induction system in my car. We had a lot of issues to work through, but I probably could offer some advice. The issues you described sounds like your car isn't getting enough gas so look at a possible clogged fuel filter or low pressure in the lines (anything less than 40lbs). Then you might see what ratio your computer is feeding fuel at (O2 sensors are a pain and not necessary). The last thing you might look at is vapor lock in the fuel rails.

I have a TWM Induction system in mine.

http://www.m-realestate.net/AC-Cobra.htm

[RPRICE]

Rick, as Matt said, I had EFI units on my bb. This was Imagine Injections unit out of Phoenix. Used Electromotive TEC 3 electronics. Never could truly isolate the problem. Main issue was under hood temp. Engine did not run hot, but when the water temp got up to 85C (well below normal) the engine would act like a runaway steam engine feeding on itself. RPMs would build and build up to about 3200 for no apparent reason. Think it had to do with the MAT. Built a nice "turkey pan" to isolate intake air from the engine compartment and as I was installing it I thought. What the hell, you have this setup for sex apeal and performance. If I cover the thing up with this HUGH turkey pan, the sex apeal is gone. And I was not convinced that I could get the performance I wanted. In a fit of anger and alcohol, I pulled it off. So I changed to a Barry Grant Mighty Demon. I know the setup works cause Shelby had the exact unit and efi on his raw body car that ran at Tulsa in 2001. This car kicked ass on the track. Ran fine. So I know it can be done, and Bob Ream at Imagine could probably have straightened it out. But I had lost so much confidence by then, I changed.
Richard