Question for Eric @ turbotweak

[Black Power]

Eric,

My 87 Gn has a 4.1 (from a Caddy, it's not a stroker) with stock heads, a 206/206 flat tappet cam, 50# injectors and old school TT alky chip, SMC progressive alky, and a 6776 turbo. Stock MAF. I have a scanmaster but otherwise nothing to monitor anything.

It idles fine, runs fine, but when it gets into high boost it doesn't knock like if it's going really lean, it just cuts out and won't rev any higher.

My theory (uneducated at best) is that the big turbo is pulling in so much air it's maxing out the maf... (actually I know it is maxing it out at like 10 psi because the Maf reading is 255) and when that happens the fueling just goes bonkers.

I need something to get this thing tuned right, because the current chip was for a 3.8 with a smaller turbo and less boost. Given the fact that I have a stock MAF, what are my options and what do you recommend? Keep in mind I am 25 years old and on a budget, so a MAFT or FAST is not even close to being on my list

That's why I am hoping one of your TT chips can save me from going insane...or even maybe a TT chip, translator, and LS1 Maf.

Any help much appreciated.

Will

 

[JOHNDEEREGN]

eric@turbotweak.com

 

[Black Power]

Where have you been my friend?

 

[Eric Stage I]

The MAF maxing out is not a problem, but the chip does need to be set up correctly for your setup. If this is only happening at higher boost, then it's most likely going lean, or the spark is dying out. With alky, sometimes you can go lean without showing a bunch of knock.
If you can give me your chip# (written on the chip label), I can see how it was programmed.

 

[JOHNDEEREGN]

Where have you been my friend?

Just busy with work Will. PM the link to TSC

 

[Black Power]

The MAF maxing out is not a problem, but the chip does need to be set up correctly for your setup. If this is only happening at higher boost, then it's most likely going lean, or the spark is dying out. With alky, sometimes you can go lean without showing a bunch of knock.
If you can give me your chip# (written on the chip label), I can see how it was programmed.

Here is the chip I am using. I bought the chip and injectors from WesS from Florida that works for AlkyControl. Worked fine with the 3.8 and PT51 turbo

As you can see, it says 50LB ALKY. The numbers on the chip itself are 8338PPP.

 

[Black Power]

Just busy with work Will. PM the link to TSC

www dot texasstreetcars dot com

 

[Eric Stage I]

That chip is not going to have enough fuel for your setup.

 

[Black Power]

That chip is not going to have enough fuel for your setup.

Awesome.

I am going to turbotweak.com right now to order another one.

 

[Black Power]

Order placed!

Do you think I can get enough fuel from 50# injectors and alky injection to feed a 4.1L and a 6776? I sure hope so

 

[rmar]

Order placed!

Do you think I can get enough fuel from 50# injectors and alky injection to feed a 4.1L and a 6776? I sure hope so

It depends. How fast do you want to go....:biggrin:

 

[Black Power]

It depends. How fast do you want to go....:biggrin:

Mid-low 11s would just make my day. I am not ambitious enough to really use this turbo to it's full capabilities.

 

[rmar]

Mid-low 11s would just make my day. I am not ambitious enough to really use this turbo to it's full capabilities.

See what Eric thinks about you saving for a wide band.

 

[Black Power]

I already have one, but for some reason it works for about 5 minutes then the needle creeps to 18:1 and won't budge from there until I shut it off and it cools down. So technically, I do have a wideband, but it's not working well enough for it to count. I think the sensor is going dead.

 

[rmar]

Need to move the repair up on the list.

 

[Black Power]

Update:

Got the wideband sensor where it works, put in the chip I bought from TT, and it runs the same. It was showing 14:1 at WOT so I turned up the WOT fuel adjustment to max (154) and it still runs lean (even spraying 1/2 windshield washer fluid, 1/2 alcohol).

So the chip is/was not the problem. I thought maybe I had my cam sensor 180 out, so I loosened the bolt and rolled it 180 degrees, and it runs EXACTLY the same! WTF!!! How is that possible?

Any ideas would be great, I am about to stuff a rag in the gas tank and light a match.

 

[Eric Stage I]

I would start with the basics and check the fuel pressure under boost.

Also, I would run 100% alky. Mixing in water or windshield cleaner will make it leaner.

What kind of wideband setup do you have?

 

[Black Power]

I would start with the basics and check the fuel pressure under boost.

Also, I would run 100% alky. Mixing in water or windshield cleaner will make it leaner.

What kind of wideband setup do you have?

Roger, my reservoir is almost empty, I will get that filled up tomorrow with some straight alky.

I am using a Dynojet Wideband Commander. I don't have any type of datalogging, so I am driving down the road watching the wideband. Scanmaster is giving me 02 counts between 740 and 800 (it depends on what mood the car is in ), but the wideband is telling me 13-14:1. I am doing 3rd gear pulls.

 

[Eric Stage I]

Your stock O2 readings look pretty normal. How new is your wideband sensor? Maybe this is just a wideband issue. Definitely check the fuel pressure though.

 

[Black Power]

Your stock O2 readings look pretty normal. How new is your wideband sensor? Maybe this is just a wideband issue. Definitely check the fuel pressure though.

I have ordered another sensor because I had problems with the current one. It should be here in a couple days. I'll take a look at the fp under boost, I hope my gauge will reach far enough for me to tape it to the windshield.

Any idea why it would run the same with the cam sensor clocked 180 out as it does when it's set correcty? (Using the 25 deg ATDC with a LED cap method).