CIS "tuning?" or just set pressures and CO?

[mikesarge]

So, my SC has been running a bit strange this winter following the installation of SSi/dansk exhaust setup. It seems like it's pretty rich all of a sudden, but maybe this is just my first time driving a car without cats, and it's normal.

Lots of vapor (not smoke, it doesn't linger, just a big cloud that dissipates quickly) on a cold start until I'm under way. Once it's warm, occasional black puff of smoke at the shift on a full throttle run to the top of the revs.

It's responsive to throttle inputs, seems to make excellent power

My engine is modified. Supertech 3.1 kit (lower comp version, I guess like 9.5 iirc, the earlier version), and 964 cams, SSi heat exchangers. My fuel system has been back-dated to a76/77 C3 FD without lambda control, which I understand is curved correctly for this engine setup (according to Al/X-faktory). Valves have been adjusted twice since the rebuild and head job (at 100 miles and about 750 miles, I'm approaching 1500 miles from the 750, planning to do one more adjustment at that point).

Not really sure what my options are here to confirm I'm running right.

Should I just find someone with a CIS test gauge and CO meter I can borrow locally (PDX area)? (Al set the pressures when he built the engine about a year ago, said they were within but on the far edges of spec)

Or is it better to get a wideband and set to work on tinkering with mixture?

I think I know the answer: do the CIS pressure checks first, then, if all is well, proceed to messing with mixture.

Any guidance is greatly appreciated. I was born and raised on EFI, so CIS is a bit intimidating, but I'm not afraid to dig in.

[Reiver]

THE best tune up thing I ever did was an on board wideband CO gauge in place of the clock. You can observe your AFI at all levels of use...idle to WOT and you will always know how your CIS is performing.
I have SSI's/dansk on a 930-10 Euro so with 91 octane the only stuff around and the higher compression I run mine a bit fat for safety and can observe that. I have the lambda in the downstream SSI collector.
Checking your CO at idle...I'd do that right now but that simply shows idle...hard to tell what the CO will be at higher throttle application and load.

[targa72e]

I second the vote for wide band. Lets you make sure things are tuned to work correctly in all conditions. CO was only used back in the day because affordable wide band did not exist.

john

[RarlyL8]

The only way to really know what is going on is with an AFR meter and fuel pressure gauge. Those two tools are invaluable.