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Timing and AFR question

I've done some searching but haven't found a definite answer to my questions. Today I was driving along side my friend in my euro 930 and he in his Carrera. We pulled away from a red light and I couldn't pull on him. We stayed even. This really bothered me so when I got home I checked my timing. It was around 32-33 degrees!! My car should be 29 degrees at 4000rpm with the vacuum hose off the dizzy can.

Question: is 32 degrees more advanced than 29 or am I backwards on this. Don't US cars run 26? When I timed it for 26 degrees my engine temp shot up about 20 degrees. Do I need to adjust my AFR when I change my timing? Did I cause it to go way lean when I changed it to 26 degrees?

The only upgrades are a K27-7200 turbo and free flowing exhaust.

You can't cause anything to "go lean" with timing.
32 is more advanced than 29.
Which engine temp is hotter, exhaust or cylinder head?
US cars are timed at 26 with the hoses off at 4000.
I thought 79 Euro cars were checked at idle with the hose on (should only be one hose for Euro). Is yours grey market for the USA or something?
True Euro cars have less centrifugal advance than USA cars, and they also take out 4 degrees at full power with centrifugal. USA cars use the back side hose for that.
How are you reading the degrees so precisely? Do you have an indexed pulley?

Quote:

Originally Posted by Speedy Squirrel (Post 4798577)

You can't cause anything to "go lean" with timing.

Thanks

32 is more advanced than 29.

That's what I thought, thanks again.

Which engine temp is hotter, exhaust or cylinder head?

Oil temp, I don't have a CHT sensor or EGT sensor.

US cars are timed at 26 with the hoses off at 4000.

Really? I thought I had to have it off. I haven't checked the manual lately; maybe I should read it again

I thought 79 Euro cars were checked at idle with the hose on (should only be one hose for Euro). Is yours grey market for the USA or something?

Yes, it's a grey market euro car

True Euro cars have less centrifugal advance than USA cars, and they also take out 4 degrees at full power with centrifugal. USA cars use the back side hose for that.
How are you reading the degrees so precisely? Do you have an indexed pulley?

No, I don't have an indexed pulley. I have 29 degrees marked on the pulley and I measured the distance between Z1 and 29 degrees and divided by 29.

Thanks for the reply.

So any ideas why my oil temps would shoot up so drastically when retarding the ignition?

That's a good question. Retarded timing will heat up the heads a bit and for sure the headers because fuel is burning later (and heating up the exhaust valves too). Your description of "shooting up" is a problem. The only oil making it to the heads come from the rocker spray bars. You also have piston squirters, but there is not that much oil to cause oil temps to shoot up.

When I initially started tuning my motor, I advanced the timing at cruise to 36 degrees and pulled the AFR's back to the low 14's. The engine ran a bit cooler and more efficiently, but that's also a function of my modified engine (heads, CR, cam, IAT).

When this car was a CIS motor, I locked the distributor down and set it at 30 degrees - idle to WOT. The idle was sloppy, but acceleration was great and AFR's we set to 12 by rebuilding my WUR.