I am no expert and I couldnt find any faults with my pfc map. It was tuned by Steve Kan. I am on my 2nd motor with this map (first one lasted about 5 days) and wanted to see if anyone could check it out for me. maybe I am missing something.

Mods are:
Stock port / DP/ High flow cat / cat back / intake / medium SMIC / 550 and 1300 cc injectors / no emissions / running 14 psi

nothing against Steve, I just want to make sure this map will be ok to add fuel and use a wideband to get the A/F ratio back to the right spot. also, while the car was down I removed double throttle and ported the TB and UIM.

I am mainly concerned with the timing and other variables.

Thanks for any help.

 

TTT

pretty please?

 

For 14PSI boost, at max torque, you are running about 2 degrees more advance than me and from N16-N20 not enough advance.

Would not have blown your engine if all componets were operating properly as I run a MP and large FMIC.

I will not commnet on fuel as this will vary more between cars with similar setups than timing.

 

This motor blew at 14 psi?? Did you spike it past there?
John

 

no spike. however, after the motor blew, I was going through everything and the rev limiter was left at 8400 from when it was tuned. dont know if that would kill it, but I would think it didnt help. it was cold outside and I took off in 1st and the tires spun til redline very fast and it hit 8400 before I could let off.

Thats another thing Im worried about, is the temp correction. while tuning I was seeing 50 C intake temps...and on cold nights I worry about it.

thanks for the comments so far.

 

What gear/rpm did it blow up at and what failed inside the motor?

Did you have the commander saving any peak info during the blow up? knock, boost, etc?

 

I was in first gear and I didnt hear anything break/blow...in fact I didnt notice it was blown until a little further down the road. it cracked a seal on the rear rotor.

I did have a commander, but I was too caught up on the fact that my motor took a dump and I didnt think to check it.

 

i remember reading that the rev limiter is bumped up so it wont come on because it does more harm then good. i'll look around and repost later

edit: our cars use fuel cut when over reved and that will make our engine run lean and add the high boost level that can become a very big problem

 

The stock location of the air temp sensor and the AIR TEMP vs INJ table is crap for a modded engine. First since the stock ECU runs so rich for normal air temps, it actually leans out the engine when it gets cold. Thus If you AFR tuned in warm weather for a leaner AFR like 11.3, most likely in cold weather you went leaner than 12. Also it heat soaks under the UIM.

That is why many of us have suggested moving the ar temp sensor to the throttle body inlet elbow or IC outlet. Then you have to normalize the table to real air density vs temperature which also has been discusses here before. Not doing so is asking for problems.

 

Compared to what I used to run the timing map is conservative, but you're obviously running on diferent fuel so not directly comparable. If you are concerned then just take a few degrees out the IGL map under boost, sort out the fueling then try adding it back in a degree at a time.

Would also keep a careful eye on boost, just in case your porting work, etc result in you seeing somewhat more than 14psi (probably best to err on the side of caution initially - better too have too little boost than too much).

Probably best to get a better rev limiter than the PFC, yours wont have been the first engine to come a cropper because of it.

 

Chuck,

When you compared 14 psi from your map to Kan's did you notice his map reference for his P rows were changed?

 

one other observation, rows P17 and P18 have the identical timing for cells N10-N20

I believe these rows are around 14 psi.

Because these rows are the same any averaging of bordering rows, would result in higher average values when compared to most maps since the timing values usually decrease as boost increases.

 

I ususally don't retard the timing on anything after 14psi. It does nothing but creating heat.

Also, how long did you stay at the rev limiter before you let off or shift? I have seen engines cracking corner seals and apex seals from hitting the rev limiter on pump gas. Also, were you low on gas when it happened? If so, I wonder if it could pick up air bubbles from the tank causing the car to run lean. I have only seen one other car that blew his engine in 1st gear and that was with him staying on the rev limiter for over 5 secs.

 

Yes, as I did a map compare first.

 

Pluto,

My statements were merely an observation. I certainly respect your tuning talent. I had just noticed there were few timing changes for rows P17 and up and was wondering why… since, I have seen some other maps where the general trend was to lower/retard timing up to P20

 

Pluto,

I was at the rev limiter for no more than a second. However, I was low on fuel and had figured that could have been part of the problem. I am not so concerned with the old motor blowing up as I am with my new one.

Would porting(smoothing) the TB and removing the double throttle and porting the UIM create too much air flow and make the car run lean?? I plan on getting a wideband and basically adding some fuel to all the boost cells and lean it out to 10.8-11.0 from there.

 

You might run just slightly leaner with the porting of TB and UIM. The map that I tuned should have plenty of margin to compensate for it. But like you said, the best way to verify it is to use a wideband.