I installed a '96 5.7 long block w/a L98 cam, L31 heads and an Edelbrock Performer (Vortec compatible) intake. I've got a 1989 TBI system sitting on top, with the stock ECM from a 350. The TBI has not been modified.

A couple of questions:

1. I've got the timing set at about 12*. Everything seems to be ok. Idle is relatively smooth, and she breathes good on the top end too. Is 12* too much, too little, or just right? My thinking is to adjust the base timing until I notice either detonation, or a lack of power - does that sound correct to you folks?

2. Should I need to change the injectors in the TBI? I thought the std. 350 injectors could support applications up to about 320HP? Correct?

3. I need a WinALDL cable! Where is a good cheap place to get one?

4. Since the Edelbrock intake does not have provision for the EGR, I simply capped off the vacuum line that used to go to it, and also capped the other line that comes out of the sensor on the left of the motor. I rarely get code 32, but it does happen now and then. Is it really worth getting a chip to eliminate the EGR from the PROM?

Thats about all I can think of for now... I'm sure I'll come up with more questions once I have a few replies.

Thanks all!

 

I will give some of my input in the order your inquired

1. You should start anywhere from 8* to 12*. The best way is to increase your timing 2* at a time, run it down the track. When you get your best time increase 2* more. If you run the same time, back it off 2*. Or if you don't go down the track you can drive it and increase it until you hear ping. This is not the most accurate way by any means (you won't hear all ping) but you can get a good base doing it like this.

2. Since you are running a mild set-up (I would say 280-300hp to be honest) I would say that you can get by with the 350 injectors with some Fuel Pressure tweaks.

3. Can't help with the cable but do a search and some guys sell them for a really cheap price.

4. I am really suprised that you rarely run a code. I would have a chip burnt for your combo anyways and get rid of certain things like EGR, speed limiter, along with setting your fuel and spark tables to make sure you have the right timing/fuel delivery. This is the best way to do it and to ensure that your setup runs the way you want it to.

Hope I helped and good luck

 

1. Ive noticed that if I get it up to about 16* it has a difficult time idleing correctly (stumbling and stalling @ idle). So 12* is where I left it at. I just wanted to be sure it was ok to be that high... I had a friend tell me that I was insane to have it bumped that high. He even went so far as to tell me it made no difference in performance to advance the timing of a TBI vehicle since the ECM controls the total timing anyways... (Is that true??? )

2. 280-300HP is plenty for my taste in this case! IIRC, I need to pull the factory regulator, and expand the spring in there a small amount? How do I know how far to go?

3. I'll do the search, thanks.

4. I'll also search for someone out here that can burn me a chip off of my WinALDL data... seeing as I don't have the $$$ to get into my own burner.

That helps a lot! Thanks for your input!

 

Yea 12* seems pretty good, its different for every car but I got by on 10* for a lil while. JPrevost used to make cables I dont know if he still is. Buy the vafpr from top down solutions, they have a kit supposedly, I havnt checked on it though. You'll want a new fuel pump if you havnt already got one. Get a chip burned if you dont want to tackle it yourself, your gas milage will like double lol. Good luck man.

 

Does that vafpr kit really make that much of a difference? Where would I see performance gains?

BTW, here is the kit! http://www.top-downsolutions.com/pro...products_id=99

-Thanks again!

 

Without a custom chip you'll see a good gas milage increase, highly modified tbi's dont take kindly to one fuel setting. This takes some grunt work out of tuning which is real nice. You can set it to say, 17 psi at wot and 11 psi at idle so you dont kill yourself at traffic lights from the gas fumes