Chip programming (long)

[Turbo Riviera]

I have a couple of questions that I think are best answered in this forum rather than general tech.

I have an '84 Riviera turbo that I'm having some trouble with.

It rich fouls plugs after 2-10 passes. average is about 4-6 runs. Then I have to put new plugs in. I feel it is the O2 sensor getting whacky from the C16 I'm using that's kicking up the idle BLM to 160 on DS. I don't think that it's a function of the WOT runs fouling the plugs... It think it's the idling around in the pits and on the return road that does it.

The car is an NHRA Stock eliminator class car so I have to keep most of the stock parts.

Here's my combo:
Stock long block '84 hot air 80,000 miles never rebuilt
no port work
stock turbo
stock cam
ACR44TS plugs
electric fan
'87 ECM, MAT, MAF
K&N
3:36 gears
10.5" TCI lockup conv.
26x9 Hoosier slicks
2.5" fabricated mandrel bent DP
2" fabricated mandrel bent x-over
stock headers
20-21 psi boost. (currently manual valve ajustment, would like to go back to boost solenoid IF it will make the car more consistent at the track)
3810 lbs race weight.
Front wheel drive
XP pump hotwired
27 deg. Red Armstrong chip

Best un-corrected 1/4 mile time:

13.63 @ 98.90
1.870 60 foot

This is a dedicated race car that sees zero street use.

I'm thinking about sticking a maf translator on it to adjust the fuel somewhat. Ultimately I think this is a band-aid for an improperly calibrated chip. Can someone make a chip that will not foul out my plugs? Jim Testa? Dave Huinker? Lets hear your opinions..

I normally race at altitude tracks between 1300 and 5800 feet. Should I be changing chips for different altitude tracks? I think the answer to this is yes. I currently am not. I use the same chip for all tracks. I trailer the car to the track so there is very little learn time for the ECM to adjust to different altitude.

Over the winter this car will be getting the following:
3 angle valve job
Lunati 226/220 cam .411 lift (stock eliminator grind)
A/C deleted
electric water pump
Power steering deleted

Goals for the car are 12.90's @ 100-102

I'd like to be able to just wire the wastegate shut (I feel the car will be more consistent this way) I know that I'll be pushing the limits of the stock turbo by doing this. Actually I'd like to exceed the limits of the turbo if the truth were known (thus the reason for the monster camshaft) I have to keep the stock turbo to be within the rules of my class and I'd like to know that I'm getting maximum airflow out of it. By wiring the wastegate shut with an engine that exceeds the capability of the turbo this would obviously lower the maximum boost. With this lowering in boost, should I be able to kick the timing up a bit??? Cylinder pressure would still be high, but charge air temp would be down.

Just thinking out loud here guys. What can we do with this turd?

Thanks in advance!

 

[JayC]

I'd find an old batch fire DFI someone is parting with and put that on there. With a "custom" combination like you have, that's going to make things much easier in the long run after you get over the learning curve.

 

[TurboJim]

Originally posted by Turbo Riviera
I have a couple of questions that I think are best answered in this forum rather than general tech.

I have an '84 Riviera turbo that I'm having some trouble with.

It rich fouls plugs after 2-10 passes. average is about 4-6 runs. Then I have to put new plugs in. I feel it is the O2 sensor getting whacky from the C16 I'm using that's kicking up the idle BLM to 160 on DS. I don't think that it's a function of the WOT runs fouling the plugs... It think it's the idling around in the pits and on the return road that does it.

The car is an NHRA Stock eliminator class car so I have to keep most of the stock parts.

Here's my combo:
Stock long block '84 hot air 80,000 miles never rebuilt
no port work
stock turbo
stock cam
ACR44TS plugs
electric fan
'87 ECM, MAT, MAF
K&N
3:36 gears
10.5" TCI lockup conv.
26x9 Hoosier slicks
2.5" fabricated mandrel bent DP
2" fabricated mandrel bent x-over
stock headers
20-21 psi boost. (currently manual valve ajustment, would like to go back to boost solenoid IF it will make the car more consistent at the track)
3810 lbs race weight.
Front wheel drive
XP pump hotwired
27 deg. Red Armstrong chip

Best un-corrected 1/4 mile time:

13.63 @ 98.90
1.870 60 foot

This is a dedicated race car that sees zero street use.

I'm thinking about sticking a maf translator on it to adjust the fuel somewhat. Ultimately I think this is a band-aid for an improperly calibrated chip. Can someone make a chip that will not foul out my plugs? Jim Testa? Dave Huinker? Lets hear your opinions..

I normally race at altitude tracks between 1300 and 5800 feet. Should I be changing chips for different altitude tracks? I think the answer to this is yes. I currently am not. I use the same chip for all tracks. I trailer the car to the track so there is very little learn time for the ECM to adjust to different altitude.

Over the winter this car will be getting the following:
3 angle valve job
Lunati 226/220 cam .411 lift (stock eliminator grind)
A/C deleted
electric water pump
Power steering deleted

Goals for the car are 12.90's @ 100-102

I'd like to be able to just wire the wastegate shut (I feel the car will be more consistent this way) I know that I'll be pushing the limits of the stock turbo by doing this. Actually I'd like to exceed the limits of the turbo if the truth were known (thus the reason for the monster camshaft) I have to keep the stock turbo to be within the rules of my class and I'd like to know that I'm getting maximum airflow out of it. By wiring the wastegate shut with an engine that exceeds the capability of the turbo this would obviously lower the maximum boost. With this lowering in boost, should I be able to kick the timing up a bit??? Cylinder pressure would still be high, but charge air temp would be down.

Just thinking out loud here guys. What can we do with this turd?

Thanks in advance!

A DFI or SpeedPro wold be the ticket, but in the meantime, what about simply using a chip with a BLM lock? I could do it (see you use an 87 ECM etc) but Jay was here first if he wants to give it a crack. We could probably run it open loop down low too so the O2 wont cause idle/off idle to go pig fat too. Maybe Steve Yaklin is the guy to talk to about this as open loop op is kinda his baby. (maxfrt1@usol.com) Maybe he can do you an MaxEffort like chip that is legal for your class? Might take a few tries to get it right tho by me. In a perfect world, you shouldnt need to change chips by altitude in a MAF system. The MAF should do its job as far as air density, but if you're pegging it, you might need some fine tuning.

BTW: Are you the silver Riv beat out my buddy Perry last year? He slept at the light and you took the trophy? If so, I know the car.

 

[Turbo Riviera]

Jim, I see that you're from NJ... In that case, I think that the silver Riviera that you're thinking of is Tony Massari's. It's an '83 carbed turbo. He'll be @ E-Town this weekend trying to set an NHRA record. Great guy!

I was definitely thinking that an open loop style chip would be the way to go if I stayed with the stock ECM. DFI is a little out of my ballpark at this time. Probably in a year or so I'll go to DFI.

I'd be up for testing different styles of chips though...

What do you think about my ignition timing theory with the maxed out turbo? Assuming I was able increase the engine's volumetric efficiency to push the turbo it past it's limit. Could I increase ignition timing due to the reduced boost pressure?

Thanks again!

 

[TurboJim]

I doubt it as once the turbo is out of its efficiency range, it heats the air too much which promotes detonation. What about a hogged out stocker with a larger wheel? Or is that not allowed either?

 

[Turbo Riviera]

Unfortunately, hogged out stock housings are not allowed. From what I understand, I can change wheels as long as they are the same diameter. But not bigger ones.