Well, it looks like I might need to get my car on a dyno and get a chip burnned to get rid of this detonation issue I seem to have developed (not like it wouldn't be a good thing to do anyway). My diagnostic skills are only taking me so far it seems (farther with the help of Pierre and Mike). So, where should I go guy's? JBA? Local would be good and somewhere that might cut me some sort of deal since I am going to be selling the car and don't really want to dump a bunch of money into it for the next guy.
i know it isn't in san diego ... but glen at vts racing can dyno tune for you. (909)981-5824 he is in upland, ca. it's a bit of a drive, but i know he does really good tunes.
There's a shop on the 101 just south of La Costa Blvd that has a dyno - should be pretty close to you. Scott's Auto I think is the name.
glen is really good, he's tuned a lot of engines. he will work on it till it is right. if you don't mind the drive, i know that you will be very happy with the tune. i'm about to do the bullitt intake manifold swap and put on an accufab throttle body. i'm gonna have glen dyno tune my car after that.
They did a nice job on my 89, but it wasn't cheap. However, they do have a "friendly" dyno which reads a little higher than JBA's. I "lost" about 20rwhp going from the Dyno Shop's dyno to JBA's. Be nice to show a buyer a healthy dyno sheet. You may have already tried this, but swapping out the distributor could solve it if that's the problem. I got a bad distributor from MSD once which caused it to ping and eventually led me to the Dyno Shop for a custom chip. Had I known it was the distributor originally I would simply have replaced it and not had to pay for the custom chip. Long story short, I replaced the MSD distributor with a rebuilt stock piece and that solved the pinging. Since Pierre has so many Mustangs, perhaps you could borrow a distributor from him.
Good point. If your ignition is bad or reading wrong you maybe running more timing than the ECU thinks you are. If you are not in a rush, maybe do our dyno day on the 7th. Once you've done that, and confirm your A/F ratio is good, then you can narrow it down to a likely timing issue. Just a thought, $40 is pretty cheap dyno check.
I thought JBA's dyno was the generous one... I did 333 at JBA andf like 310 or so at the dyno shop, same mods, no cool down prior to the dyno shop pull...
There is no right or wrong answer, different cars get different results depending on their actual HP and TQ. The calculations and the dyno equipment are different. I'm not sure I understand why guys want to show a higher number when its calcuated differently. I realize you want the largest number, but to me its like stating my annual salary in Indian Rupees or something (FYI todays exchange rate is 43.6 to 1). You may be a millionare! Comparing one car's DynoJet numbers and someone else's Mustang Dyno numbers is not a comparison at all. Just my $.02
John, where is "The Dyno Shop"? And not a bad idea to try swapping a distributer, (Pierre?) I was actualy considering the TFI modual because I know it is very old. 351c-ya, I know where that shop is, have you had any experiance with them? slapyo, if I were to go all the way to Glens, I would probably just go to Swansons. But I will keep it in mind (Swansons is real expensive). tschlientz, is that why my last raise was in Rupees and, the last time I had the car on a dyno the A/F was perfect but something could have changed (obviously). You guy's, thanks for all the input. I should give you more details about my detonation and what I've done so far to troubleshoot it.
Dyno Shop is in Santee off of Prospect two miles or so west of hiway 67. I'd swap distributors first though. The Total Performance shop is just down the block on Prospect and Greg Gossett probably has several take off distributors laying around. If you can't borrow one, you might call him and pay him an hours labor to swap one and see if that works. He did my engine and is a really nice guy. Are you running an FMU? Perhaps it's not working as well as before and leaning out the AFR (?). Maybe try a richer disk if you have one and see if that helps. Could also be the vacumn line to the FMU is leaking. Good luck.
Ok, thanks. This is the deal. I haven't changed anything but out of the blue (in fact, the day we went to that car show in Carlsbad) I started getting detonation in 3rd and 4th gear at around 4000rpm and above and over 6psi of boost. I have alway's ran with my SPOUT out and timing locked in at 29 degrees initial. I have an MSD6BTM set at 1.5 to pull timing under boost. I have an FMU calibrated at 6 to 1 for my 30lb injectors. I have never really had any detonation issues, except when I tried running with the SPOUT in and bumped my timming to 12 I blew a head gasket. But since then, SPOUT out 30 degrees, no problem, untill now. What I have checked: FMU, supplied air pressure, fuel pressure increased. BTM, supplied air pressure, timing pulled back. Replaced 02 sensors. Replaced fuel filter. Cleaned MAF sensors and air filter. Checked timing, tried setting it as far retarded as 22 (degrees SPOUT) out and pulling 2 degrees on the BTM, tried setting base at 10 (SPOUT in) and pulling as much as 3 on the BTM. Pulled codes, got a "purge canister circuit fault", I replaced the sensor on the vacume line leading to the purge canister.
I only went there to get a quick pull after I changed carbs; nice guys, but I think they'd be on the expensive side if you're looking for an actual dyno tune. They are into Chevy's more since that is what they race.
Based on what you said, seems to me you dont really want a dyno tune. If things were fine, then went bad without other changes, then there has to be a system issue - fuel, ignition, etc. Its possible they could tune around it and make things work, but it might just mask the real problem. Just my opinion, but I think you would be better off spending the same $ on a few hours of labor and get a good diagnostic. Maybe its something easy, or maybe not, but at least you would know where you stand. Sounds to me like you covered the basics. Good luck whatever you do, let us know how it turns out.
I think it's the plugs, Bill. I suspect a couple are fouled and a few others have worn electrodes. Change 'em!
Thanks John! Yeah I should do the dissy swap and see what happens and then it wouldn't be too hard to swap out the MSD6BTM just to rule that out if need be. Oh, and we don't call them "freedom fries" any more?
