Hey guys!

I'm just getting my truck up and running, and I'm busy trying to hammer all of the bugs out of my setup.

I know that there are some things that are most definitely contributing to my rich condition, but I'd still like to get a few other opinions incase there is something I've forgotten to check, or not even thought about at all.

First things first, current engine specs:

- 4 bolt main 350 bored .020 over
- Comp Cams XE262-H (218 in / 224 ex @ .050 duration with .462 in / .469 lift, and 110 LSA)
- Stock smogger crap heads + dished pistons (small valves, large combustion chamber aka, poor flowing, low compression smog crap)

I know, my cam is not really that suited for EFI, but its what I have in the engine, and so I've gotta work with it. I've already got a new engine block at the machine shop so I can build myself an engine far more suited for EFI.

Current plans include:

- 4 bolt main 350 bored .030 over
- Comp Cams XE256-H FI (212 in / 218 ex @ .050 duration with .449 in / .456 lift, and 112 LSA)
- L98 heads with mild port work, and mildly dished pistons to place my compression ratio at approx 9.2 - 9.3:1 (I want to run 87 octane)
- Ported stock intake

However, I won't have this engine done till sometime in the winter, so I need to get this engine running good enough to go camping this summer.

All my engine's sensors are hooked up, less the 02 sensor, and all give a believeable reading according to Datamaster. I haven't got my 02 sensor hooked up as the engine is still currently equipped with longtube headers, but I want to convert to a set of old Ramhorn style manifolds, and install the 02 sensor directly below the collector. The 02 sensor doesn't stand a chance of actually working correctly down in the open header tube, so I opted to just leave it disconnected.

The EFI intake is a stock `85 Trans Am intake, converted to speed density. The cold start injector is still installed, but not hooked up, just acting as a plug for the hole, and I've already made sure that it isn't leaking. Injectors are 19 lb/hr Ford truck Bosch type injectors. I do know that at least one of them leaks above 20 PSI of pressure. Fuel pressure is stock at 43 PSI without vac applied to the regulator, and 38 PSI with.

The prom is totally stock AUJP less changing the injector constant to 19 lb/hr, and disabling VATS.

As it sits, the truck will start on the second crank of the engine, but needs more throttle to continue running. I have to keep the idle screw turned as far in as it will go so the engine will idle at about 600 rpm, cold without any extra throttle. I have not set minimum air as of yet. At this RPM, it will only run on 4 or 5 cylinders, and is so rich that it makes your eyes burn! Big cloud of black smoke from under the truck, you'd think the thing was a diesel!. If I give it more throttle, it leans out, and runs on all 8. Throttle response is incredible, far better than any carb I've ever run, even with the EFI barely running correctly.

Tommorow I plan to pull the IAC and make sure its in good shape, and set minimum air, along with disabling emissions systems that I don't have installed, and a few other minor, easy things to change in the prom. I'm hoping to have proper exhaust installed by the end of the weekend, and have my 02 sensor hooked up and working.

Thanks for any other opinions on things that I may have overlooked that could be causing such a rich condition!

Russ

 

Install your O², then run the engine to closed loop a few times. The Integrator needs to see actual values from the active O² before it can write BLM fuel trims. Until then, you're running on AUJP tables (which are even a little fat for the stock application) in an engine that may not need quite that much fuel. You should expect it to be rich.

 

Till you get the o2 hooked up you may try just upping the injector constant to get less fuel. Just as a patch to get it to stop smoking until things are correct.
Be sure to use a heated (3 or 4 wire o2) sensor if your going to put it in the collector. Idle will cause it to cool down and drop out of closed loop.

 

I'm about half done my exhaust, need a pipe flaring tool, doughnuts etc and then I can get my 02 sensor hooked up and working correctly.

The thing runs so rich that when I pulled my headers off almost two days after I last ran it, raw fuel poured out of them when I tilted them downwards!

I'm putting stock log style manifolds on to avoid the heated O2 sensor issue, it can get downwards of -40F here in the winter, so I need something that'll keep the 02 sensor close to the exhaust ports. By collector, I mean just below the manifold to Y-pipe connection. I'll weld an 02 sensor bung in. I can't use TBI / stock TPI manifolds becuase of the exit points, the driver's side will hit my clutch slave cylinder. So I need to use stock truck manifolds for their exit points. They won't warp as bad as the old ones do anyways

 

Alright, got my exhaust done up, and tried setting my injector constant to 24 lbs/hr

I'm still getting black smoke, but it isn't nearly as bad as it was. Truck also backfires on occasion now...

I'm thinking that chances are my problem is with one or more of the injectors being stuck wide open. And my guess is on cylinders 2 and 8. Both of them had gas soaked spark plugs when I took them out today. I tried tapping on the injectors with a wrench, but I'm still loosing all 40 PSI of fuel pressure in about a minute, and the truck floods right out.

Hopefully after I get those injectors replaced, I might be good to go

 

sounds like u have some bad injectors or bad programing... mayb even interference on the wires.

 

Oh, I know for sure that both are way outta whack, lol

Engine is nothing like a Vette L98, which the fuel curve is for, or a Camaro L98, that the spark curve is for. However, I can't really do any tuning until I am sure that the rest of the EFI components are working correctly.