12-02-2012, 05:20 PM
Join Date: Jul 2008
Total Cats: 1
Tuning my new to me Link'd 93 Turbo
Picked up a 93 recently. Turbo charged with a journal bearing turbo on an BEGI era FM manifold and down pipe. NPR intercooler. LINK ECU. RC 440 injectors. Big loud exhaust. 1.8 rear with rx7 clutch lsd etc etc.
The original bottom end was replaced with an automatic block after bending a rod because of a stock injector. At the same time, the head was done up with porting, valve job, and the exhaust cam from the automatic was installed at some point.
8 years ago, this thing was "The SH%T!" lol.
I finally move up to a programable ECU with the LINK and of course it's considered antique at this point. Still, it's much better than my previous, AFPR turbo miata.
Other than very basic fuel tuning, the car was running on the default turbo maps. I've done a lot of fuel tuning in the non-boosted rows since getting it and it runs great. Starts and runs in the cold well. Idles perfectly. Boost control is working relatively well at this point as well.
Still, the response seems soft. I figured it's because the default LINK maps are conservative even for the stock compression ratio so maybe it's REALLY soft for the lower compression pistons in this car? Also, the EGTs both cruising and in boost are higher than they should be.
I've been slowly pushing the timing up across the whole map but I think I'm being too conservative. I've been reading everything I can find online about tuning the link and I've looked at all the timing and fuel maps I can find.
I guess my question is how much more timing does the half a point of compression drop with the dished auto pistons allow? I know no one can just answer that but I'm looking for advice just on overall approach I suppose.
Do I just keep pushing it up until I start to see knock under load and then bring it back down until the knock stops? Is there "too much timing"? Or maybe, do I just turn up the boost because of the low compression ratio?
Sorry for the long post...I'm just excited to be playing with an ECU!