leed

Eagerly awaiting your write up.
Off topic, but one of these days Im gonna put my timing gun on a car during a dyno pass. I know Im gonna be suprised at the results.

scttydb411

if your dizzy is set at the timing at idle in your maps and you're data logging in crome pro you'll see exactly what your timing is...unless your implying that it's not the case and the ecu isn't advancing per the map on the chip.

jd, i didn't have time to read through all the thread on pgmfi, but are you talking about the wierd timing setting in the y8 map?

i just changed the map from 21.75 to 12 and then set my dizzy at 12. datalogging will only show the timing that is in the cells of the map that is burned to the chip. it doesn't take into account that the dizzy is advanced or retarded from that. i tested that out yesterday via cromepro and some datalogs. it was saying 12 when my dizzy was set way off from that since i changed from an uber p06 based map from 16 at idle to cromepro y8 (vtec disengaged for y7) at 12.

the p06 and y8 locam maps are pretty similar and yielded the same max hp/tq #'s, but the dyno curves were a little better on the y8 locam maps for my y7.

Boosted_StinkyNuts

+1 Bout time someone tries solving some Y8 tunning/timing issues. If I still had a Y8 dizzy it'ld be yours in a heartbeat man.

Tom-Guy

I'm at my boy Goforth's, he has a box of this ----. Literally 45lbs of distributors. I have 60 lbs of distributors, but none of them have coils or ignitors. I am seething with jealousy.

Y8 dizzy = B7 dizzy, with a different connector pinout. Everything is the same, it is the *exact* same distributor, marked P06 inside and on the reluctors and everything. I even checked the pickup/reluctor orientation, to eliminate dizzy shaft differences - nope, exact same part.

It's in the cam gear. You know the ****** 1/2 tooth off piece? That has 37 teeth? 37 teeth into 720 degrees rotation for every complete 360 of the crank? What is that, ------s? 9.72 degrees or some ----? The dizzy rides off that 9.72 miscalibration... now you know where 21.75 vs 12.00 degrees comes from.

Tom-Guy

PS please send anyone you know who has first hand experienced the infamous D16Y8 oilling problem/engine failure bit. I have a few specific questions to ask them, and do not want to skew my results by telling anyone what my suspicions are.

joey at oldschool----------er dot com for teh win, kthx!

93turbo16

I had the same experience with Samsons car. His car has like 12 degrees of timing in it at like 7-8 psi. And his low cam definitley needed timing added to it and still does. He spools his turbo like crazy because of it. Makes for a crazy power band but not the best thing for the motor.

Good post though, I would like to see some reasoning behind it as well. The P2P maps are gay. :P

scttydb411

hmmm...so does this mean i should change my map back to 21.75? i guess i should pull the timing light out while pulls at a steady state on the dyno and retract my comment earlier to see what it is doing. this might answer why my car has seemed to intermittently studder at idle since i made the change from the p06 map to the y8 locam map. what do you think?

Tom-Guy

Steve's D16Y8 was very similar. We had very limited time + I was more concerned with the engine being safe and making good power while doing some of leed's infamous 3rd gear panty rippers. The T3/T04E was spooling by 3000 rpms, and on some of the logs (18 samples/sec) the boost jumped from the 3.x scalar to the 7.x scalar without registering on the 5.x scalar in the logs. There was also a BIG drop in power for a second between 3500-4000 rpms where the Y8 timing maps pick back up, and I did not have a chance to address that. Sometimes his BOV flutters between 3500-3900 rpms, compressor surge?

FYI, Steve spoke to Elspool on HT, he's running 9 degrees at 10 psi, and then locking the timing at 9 degrees for higher boost, making power in the 370+ whp range.

Honduh went the right way with a KS equipped car, IMO. I think Honduh sets the P2P ignition maps as a minimum timing map, and adds more timing in based on KS-feedback. This is why the low cam map likes/NEEDS much more timing, as the KS starts putting out trash in the higher rpms and the ECU stops paying attention to it. Ever seen some KS equipped cars that get locked into a knock-feedback loop where the ECU tries to pull more and more timing, until the exhaust valves are glowing red hot and causing pre-ign that continues to tweak the KS, ultimately destroying the engine? Nissan and Mitsu are famous for it, although it takes a bit more to blow 4G63 than SR20. I'm sure other makes are as well, but I don't get out much aside from Nissan + Ford + my best friend being a DSMtard. Anyway, I digress.

P2P maps are where you start, and you just tune from there. It is not hard, it just takes a couple hours.

Take the whole map and subtract -9.75 from it, and dial the distributor so that it likes up with 12 degree mark on the crank pulley. Plan on adding more timing in the low cam map *especially* below 4000 rpms, and probably add a tad of advance in the high cam NA region. Seen SOHC MShue's post on HT about det-cans, in the FI forum? Read it, learn it, live it.

I'm plodding away at the writeup now, I'll post my the final .bin to the pgmfi.org thread. Keep in mind the timing is still off in the low cam area, and that there was next to zero tuning done on the high cam below 7.5 psi.

Bone1

38 teeth...........

360 / 38 = 9.47368421

1/2 tooth cam timing error = 4.73684211

Tom-Guy

Uh, no.

360 / 37 = 9.729729729

1/2 tooth cam timing error = 4.864864864

The crank turns twice for every cam rotation, so double the offset @ the cam to get degrees of crankshaft rotation, and we are back up to 9.72.

Just like that worthless i-VTECH ---- claims intake cam flops pointlessly around 50 degrees (with referrence to crankshaft), but the oil-pressure-controlled adjustable cam gear only pivots 25 degrees.