944 Turbo DIY TunerPro Chips

[zooklm1]

This reminds me, I'd like to find a volunteer or three to test out my baseline performance chip for the 951. Only catch is we'd need a stock car with wideband (and preferably a boost controller) so we can log the AFR and fine tune as needed. If you have or know of anyone with a stock 951 who might be interested, please let me know! I'd supply the chips for free, and dial them in based on the wideband logs. I'll even throw in a pre-wired knock counter to add more data to the mix and make it worth you while!

Tom did you find anyone? I wouldn’t mind being a volunteer I have a manual boost controller, boost gauge, and an arm series x wideband installed.

I have been working with Tom on the chip project since early May. It has been quite a learning experience. A big item was that at more than 11-12 psi boost, you can not get lower than 12.2 AFR above 5200 rpm (at WOT) with the 2.5 bar FPR. My goal is to get to 15 psi boost and have changed to a. 3 bar FPR to get to a safe AFR. I should get a new chip to try tomorrow. I am almost completely stock with the exception that I have a 3” down pipe back CAT delete exhaust with 38 mm tial wastegate.

[vacobra]

This reminds me, I'd like to find a volunteer or three to test out my baseline performance chip for the 951. Only catch is we'd need a stock car with wideband (and preferably a boost controller) so we can log the AFR and fine tune as needed. If you have or know of anyone with a stock 951 who might be interested, please let me know! I'd supply the chips for free, and dial them in based on the wideband logs. I'll even throw in a pre-wired knock counter to add more data to the mix and make it worth you while!

Tom did you find anyone? I wouldn’t mind being a volunteer I have a manual boost controller, boost gauge, and an arm series x wideband installed.

I have been working with Tom on the chip project since early May. It has been quite a learning experience. A big item was that at more than 11-12 psi boost, you can not get lower than 12.2 AFR above 5200 rpm (at WOT) with the 2.5 bar FPR. My goal is to get to 15 psi boost and have changed to a. 3 bar FPR to get to a safe AFR. I should get a new chip to try tomorrow. I am almost completely stock with the exception that I have a 3” down pipe back CAT delete exhaust with 38 mm tial wastegate.

Very similar to me I have a tial also but stock exhaust. How does it run compared to stock

[69fi]

Is it possible you’re pegging the duty cycle on the injectors?

[Tom]

Is it possible you’re pegging the duty cycle on the injectors?

With the stock injectors and 2.5 bar FPR, we almost certainly were. It was a bit of a surprise to me how little headroom there is. Probably plenty of room at stock boost levels and stock air-fuel ratios, but then add 4 or 5 psi and shoot for under 12:1 and you hit the limit fast...

[vacobra]

Is it difficult to start off tuning without experience? I think I might give it a try I’m just nervous about blowing up my car.

[whalenlg]

I have been working with Tom on the chip project since early May. It has been quite a learning experience. A big item was that at more than 11-12 psi boost, you can not get lower than 12.2 AFR above 5200 rpm (at WOT) with the 2.5 bar FPR. My goal is to get to 15 psi boost and have changed to a. 3 bar FPR to get to a safe AFR. I should get a new chip to try tomorrow. I am almost completely stock with the exception that I have a 3” down pipe back CAT delete exhaust with 38 mm tial wastegate.

My data point is somewhat different. I am running a mostly stock 1989 DME chip (only the boost limits have been removed) with a Lindsey DP wastegate and manual boost controller with an Evergreen RaptorX turbo. For some reason, I get AFRs below 11 with the 2.5 bar FPR and stock injectors at 15psi max. Tom and I have both scratched our heads on this one. I bought a new wideband o2 sensor, changed the o2 sensor cable to gauge and still get <11 while under full throttle and boost. I didn't touch the timing or fueling tables. Same thing happens on a stock 1986 chip as well IIRC.