eclou

Got the 27/6 installed (7200) with custom Guru chips and eBay 52# Lucas injectors. After 1 hr of dyno tuning the best I could manage was 292 rwhp and 293 rwtq at 16# boost. A/F is not ideal and car still has slight midrange stumble. Will scan dyno tomorrow for all.

NZ951

So Danno didnt map your chips right? Thats a bit of a pain dyno runs are not cheap! Not bad figures stll...

Duke

Seems like good figures for a K27/6 at 16 psi!

Songzzz

You have the exact setup like one of our guys here (Taiwan). 292rwhp at 16psi is very very good. At what rpm?

eclou

Danno mapped my chips based on the config I told him. The A/F actually is not too bad, but at cannot subtract anymore fuel up top or add more midrange due to the limits of the ARC2. Danno also told me he would re-map to suit my car as needed so I will try to send the plot to him and see if it can be improved.

I think my stumbling may be due to poor injectors. There is a bit of hesitation under load despite a safe AFR. I bought some used Lucas 52# injectors off eBay and may go ahead and buy new Racetronix Siemens units. It doesn't pay to cheap out!

I got charged $75 for dyno tuning for over 1 hour. The shop is run by a group of Hong Kong ex-pats who are impressed that I can speak Chinese with them. I think my butchering amuses them and they give me a discount.

eclou

Here is the dyno:

http://www.986host.com/gallery/eclou/27_6dyno?full=1


The red was the last run after 1.5 hrs. 2 runs prior showed 293 rwhp. The downspike on the blue run was a stumble. Not sure why it did so but it may be crappy injectors

eclou

Any comments on the AFR? Anyone?

Sam Lin

A/F looks good to me, nice safe tapering off in the high end, though you could probably safely lean it out all the way across the board (perhaps with adjustable FPR?) to get high 13s/14 at 3-4.5k and roll off to roughly 12 at 5.6k. It'd gain a little power and spool a tad quicker, and still be safe. Basically a blanket ratio increase of one point. Where in the RPM range is the "stumbling?"

Sam

eclou

stumbling is around 3-3.5k IIRC. I think the injectors may be at fault. Used ones off eBay that looked USED.

Tom M'Guinn

I'll trade a/f graphs any day! I wonder if turning the fuel pressure up a little and turning the MID or HIGH **** down a little would help level it out? IS your ignition strong? The graph is too jagged, no?

Tom M'Guinn

Sam, I was always thought 13:1 was on the lean side and 14:1 was outright too lean under full boost. Is that what you run?

eclou

I am at absolute minimum on the high ****. mid is at 3:30, low at 11:30, accel at 1:00. I run a fixed 3 bar FPR. I am interested in the Super Apexi but everyone seems to say it's not very compatible.

Sam Lin

14.7 is stoichiometric, in reality roughly 14.3. Below that is all rich, ideal power is made around 12.5-13.1. The reason I'd run a 14 in lower RPMs is to help the turbo spool quicker, and then have it taper to a safe rich amount (12-12.5) by redline to prevent detonation, the risks of which increase with RPMs.

Sam

jimbo1111

That #6 hotside spools up quick.
What fsq setting on the dme do you have it set to?

eclou

1st click on Danno's custom chips