EFIDynoTuning Forum

Decipha, had a guy bring a gorgeous 64K mile '93 LX for me to give it a once over, Car is equipped with Trick Flow U/L intakes, T.F. heads, Anderson N-41 cam,shorties,Bosch 30# inj's, BBK maf cal'd for 30# , Dynamod ignition module,and either their distributor or Possibly Summit, found it had a Quarterhorse in it with a tune from ECU Exchange ( it had apparently been refurbished on 3-10-2022), everything looked practically new inside, after looking the tune over I noticed they still had the base fuel, .75 load up still at 11.88 so, I changed that to 12.8, Added a little idle air it was idling at 1200 rpm any less than a 1000 at it would surge and die, he wasn't interested in spending money on tuning it when he could simply turn the throttle screw and I didn't have time to tune it correctly anyway. Upon driving it I noticed that the timing at WOT wouldn't go past 24*, (saw 25* on datalog below) It looked like they were using only the sea level table for timing at at the upper loads were only commanding 24* ( 2* less than stock!),The only timing changes from stock while doing a compare showed the Spark & Fuel Lugging Load vs RPM table, the WOT vs BP zero'd out and the WOT vs RPM table changed, so I set them at a conservative 30* at .75 and 32* at .60, datalogged it, nothing changed, Found WOT vs RPM table hadn't been zero'd out so took at chance & set the WOT vs RPM table to 32* 3500 rpm's-up and datalogged it, still at 24*, I saw no other spark tables that were populated, IAT's and ECT's were fine, so my inexperience doesn't tell me what's going on, could they have possibly put a hard limit in the computer that the QH can't modify?? I'm sure that's probably a dumb question but I had to ask. I didn't have another spout to try but it would seem to be working as base timing I verified at 10* and it advanced when installed. I have attached the tune I modified, and the last datalog at WOT, if you could look them over I would ***GREATLY*** appreciate it!!!

For some reason it won't let me load the .CSV file! says: "Invalid file extension" ? Using EEC Analyzer to view them

Its using the sea level table.

You definitely should not command that high of timing with an aftermarket distributor. Its not uncommon for aftermarket distributors to have timing +/- 10 degrees off per cylinder. Logging 24 degrees you probably have 14 on some cylinders and 34 on the others. They probably had to reduce it due to it knocking.

You need to read the forum rules and the pre tune info on the homepage.

If your going to post a log post a tunepro xdl log. I don't bother with BE logs as it takes far too long to evaluate.

Ok, I'll read the rules, Sorry, I hope I wasn't out of bounds!! If we want a given timing setting, how do we know we're getting it, on all my other cars what ever I commanded, I was seeing really close on the datalog, this one never varied more than * and a half from 24*. No matter what I did. I was going by the spark write up where it states for TW heads to have around 35* at WOT, did I misinterpret what that was? SORRY!! for all the questions I'm just trying to learn:)

No, the forum rules tells you how to post the file.

You never changed the commanded timing in the sealevel table.

You need to read the pre tune info for specifics on the distributor.

Ok, I'll read the pre tune info too! I changed the .60 & .75 load tables to 32* and 30* respectfully in the Spark-Sealevel table, FN 904A shouldn't that have changed it? In the spark scalars, Z_SPKINT is set to Sealevel Only as well. I'm using Binary Editor for tuning ,BTW. Please be patient with all the questions!

Edit: Just read the distributor information in the Pre Tune page, GREAT INFO!!!, I have always recommended the Ford distributors but for different reasons that you explained, Is there a good source for them or a suitable alternative? Almost all push rod engines come to me with aftermarket dizzy's, (I won't tune one with an MSD under any circumstances!) and most of the originals have at least 100K miles on them, trying to convince a guy to buy a used 100K + mile 35 year old distributor to put in place of his $300-$400 brand new one is gonna be a hard sell! LOL!

rich porter is the china oem remans you get from the parts store
they use oem tangs so all good

I usually take the aftermarket distributors off and toss them in the trash. Billet ones and all.

Ok, I'll recommend he just buy a parts store one and hope for the best, Thanks so much for all your help and patience with me!!!

There are some ford ones on ebay from time to time.

Thanks, red5.0fogger!!

I know this is a little late, but would the Pro-M shutter wheel help fix the aftermarket distributor?