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JBL930 JBL930 is offline
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Join Date: May 2006
Location: UK
Posts: 1,172
Brian, i know what you mean, CIS has no way of changing fueling dependent on air density, 1.0 bar on a hot day with a particular set up may be fine, the same set up on a cold day and you will likely be running lean! That's why i guess ALL modded CIS turbos should have either a LM1 or Zeitronics AFR gauge permanently set up in the car so it can be monitored. And 'absolutely' should have an adjustable WUR so that adjustments can be made to suit.

Keith, the engine was fresh, new rings, rebuilt and ported heads, 964 cams, 1.0bar spring which netted a little over 0.9 (so mild boost), B&B style headers, fabspeed muffler, IA air box, IA fuel head which was done in exchange, i sent my euro black cast iron one over and got a silver US ally one back!?
K27HFS just installed.... Not sure on the power, it was around 415bhp (flywheel) with the garrett on there earlier with the same boost. The car ran like crap with the 7th injector, fueling was all over the place, car bogged down with so much fuel. It ran great with the HFS and ditching the fueler!

My logic was that i had the car dyno'd before the 7th injector was fitted and with the garrett turbo installed, it was showing it going a 'tad' lean right up at the top end. So the 7th injector was fitted to solve the issue. I didn't know then what i know now!
My mechanic was only too aware of the WUR mod, but convinced me this 7th injector was the way forward. CLOWN!
Anyway, i had a friend bringing an adjustable WUR to the airfield, i thought i would do a run with the stock WUR first and keep an eye on the fuel with the LM1.
The mate i had in the passenger seat was reading my figures and i told him "if you see it go above 12.2 tell me to back off"! As we went away he was saying "11.1.......11.2.........11.5...........11.8....... .........12............12.something..............B ANG!

It's history now, the car has a nice fresh 993tt engine in there now, good riddance to the CIS system as far as i'm concerned! But i'm still really interested in it, and i'm still a bit sore that my mechanic at the time didn't get the car set up properly, i shouldn't have had to be ****ing around with it myself..... It had been YEARS of backwards and forwards, one issue after another, turbo's seizing up, fueling all over the place, i'd had enough and took things into my own hands!! The saddest thing being i HAD an adjustable WUR with me, but decided to do a run first, and the rest my friends is history
87 930, 993 turbo engine, RS Tuning 520PS/515lbf-ft, Arrow Rods, ARP hardware, Solid lifters, G50-50, RS Flywheel, 890nm Sachs clutch, RSR coil overs all round, 993 C4 calipers front, 930 fronts on the rear, Ruf Speedlines.....
Old 540 BMW, XB12S Modified, for being a total hooligan
Old 02-07-2010, 10:16 AM
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