I am just wondering because I was thinking about going to the dyno soon. There is no way I can afford a PMS or tweecer, so I was thinking about having a custom chip burrned. A couple of people are tellling me that the chip is useless. My question is, what do they do at a dyno that could add that much horsepower w/out burning a chip. Do they just adjust fp and timing to optimum performance or is there other stuff adjusted as well? Does anyone have any good experiences with chips?
Is a dyno worth it w/out a chip?
- Thread starter Rock777
- Start date
BaXTeR3221 said:
I have heard from some pretty credible members on this site that the computer will adapt to the new fuel pressure and change the fuel tables back to stock EXCEPT for WOT, which is really the only place I care about it being changed. I know this is debatable, but some pretty intelligent people have looked into this.
The reason I ask is because I went to the track the other night with the mods in my sig and my mph was consistently 104.xx, which is way too low. I know it needs to see a dyno, but I've messed with timing between 14-18 and fp between 39-44 and was wondering what a dyno will do differently? By no means am I saying a dyno wouldn't help me, I just want to learn more about what they might do. Some personal experiences N/A with or without a chip would help convince me, please.
I guess I am just wondering if it is probable that a tune and/or chip would bring my hp to the level where my mph would be at least 107, which is where it should be at the very least. Are there any other variables that I might be overlooking?
I suppose a slipping clutch could cause this effect as well, right? I am just dying to figure this out. 
I suppose a slipping clutch could cause this effect as well, right?
I am just dying to figure this out. 
25thmustang
Mustang Master
Timing and FP can help a bunch. I went to the dyno last year with 259 hp, and left with 272 just messing with timing and FP. Then after the FP got messed up I lost over a mph at the track (it was messed up on my 12.56 pass also). I went back to the dyno and played with timing again, to get the car ready and only gained about 3-4 hp. Sometimes it helps sometimes it doesnt...
I dont run a chip, and dont know if I ever would.
I dont run a chip, and dont know if I ever would.
25thmustang said:
Given how low my mph was, do you think timing and fuel pressure could make a decent significant improvement in my trap speed, or is there probabaly something else. You can see my timing and fp in my sig, and I don't think they are set too conservatively. The only other thing I can think of is there is a ticking on my pass. side, but is not exhaust. It sounds like it is under the valve cover, but I don't know for sure yet. You can't hear it at idle, but can while driving next to a curb. I wouldn't think that even if it is a rocker, that it could effect my performance that much, but I'm no expert.
I am in the process of having my rear-end rebuilt right now, so that will help a lot with my E.T., but we will see about the mph. I know spinning doesn't generally effect mph, but if I am spinning all the way through 1st, part of second, and chirping 3rd, that will definitely effect my speed up top.
25thmustang
Mustang Master
The spinning should affect it that much. I used to trap mid to high 106 on slicks, and then on street radials with spinning, the car trapped 107-108. The little spinning helped the top end (also the tires not havng air out of them did as well).
Going to the dyno cant hurt. I would say take it there and see the power it makes...
Going to the dyno cant hurt. I would say take it there and see the power it makes...
25thmustang said:
Yeah, I think I am going to take your advice and take it to a dyno. As soon as the rear-end is rebuilt, I am going to take it back to the track, see how it does, and then go from there. I am definitely shooting for 12's once the rear-end is done, before I even take it to the dyno. I don't see why with my mods and DR's I can't be running 12.5's, 12.6's with a good tune.
25thmustang
Mustang Master
You should but dont expect it first time out. It takes a while to get used to a car, where it wants to be shifted and such. Everyone progresses through the timeslips until they find exactly what it wants!
i just got back from watching a friend of mine get his stang dynoed. All he did was adjust the fuel pressure and timing. and yes, it made a difference. This was on a mustang dyno. His car was not to radical and was pretty close on the air fuel to begin with, but by bumping the timing up 3 degrees and the fuel up 3 lbs he picked up 5rwhp. Not a wad, but it was an improvement. Depending on how bad u r now, you could pick up quite a bit. where are u located?
Michael Yount
Mustang Master
It's really hard to tell how much you might be able to pick up. The chip burner can alter the w.o.t. fuel and timing curves. If they're in pretty good shape now - then you won't gain much. If they're not, then you may pick up some power. You won't know the potential for gain until you make a few pulls with the wideband and see where the a/f ratio is. Usually things are a little rich - and leaning it out with the chip picks up a bit of power. Also, adding a bit more timing advance (total) helps peak HP. In any event, unless something is really wrong with the motor, I wouldn't expect to pick up more than 10-15HP on a naturally aspirated tune with your mods. Where the chip can be more helpful is cleaning up other drivability issues - loading the transfer function of the maf into the ecu, altering cold start characteristics, adjusting idle speed - stuff like that. But it takes a burner that really knows their stuff. The reason folks like the twEECer's and PMS so much is you can play with things changing them just a little to see how it responds - and over time, they keep tuning and making it better and better.
Only you can decide if it's worth spending the money. But - you mentioned clutch - be sure you have the car in good working order before any pulls. It works the car pretty good to make multiple pulls and you want to be sure it's up to the task before you sign up to spend the money. Once you get strapped down and started you've spent some big money - if it breaks on the second pull - you've spent a good bit of the money with nothing to show.
Only you can decide if it's worth spending the money. But - you mentioned clutch - be sure you have the car in good working order before any pulls. It works the car pretty good to make multiple pulls and you want to be sure it's up to the task before you sign up to spend the money. Once you get strapped down and started you've spent some big money - if it breaks on the second pull - you've spent a good bit of the money with nothing to show.
Michael Yount said:
That all seems pretty logical. I guess I am just surprised at how low my mph is even without a tune. It just doesn't seem likely that they would be able to pull that much more out of it considering what the settings (ie. timing, fp) are already set at. Then again, I don't know a whole lot about the wot fuel and timing curves, and the chip might effect them quite significantly. Its just frustrating to have put this much time and money into something to run times that people with a lot fewer mods are running, but I'm sure it'll come with time, it BETTER come with time.
Now I just have to find a local dyno/tuner that won't try to shove a PMS down my neck. Thanks for your helpful insight Mr. Yount.
Michael Yount
Mustang Master
Keep in mind - between dyno time and the chip/chip burner's time, you're gonna spend about as much as you could probably buy a twEECer for. And with the twEECer, you get to keep playing tuner for as long as you like. If you're gonna keep the car and continue to change things - I'd strongly consider buying the software/hardware to tune yourself. Get into the twEECer yahoo boards and others will help you learn.
Michael Yount said:
I thought the tweecer would cost in the $500-800 range if I find a deal, plus I'ld have to buy a labtop. I think the dyno with a chip burned is $599. I never really looked into tweecers so I am not too familiar with the cost. Hmmm, definitely got me interested though if the PMS and the dyno/chip were in the same ballpark. I'll have to look into that more.
I'm paying $550 for my chip. I can have up to 5 different "settings". I'm planning on doing one for 93 octane, one for race gas, one for 87 octane and a limp home setting. The MAIN reason i'm getting the chip burned besides power is because the car will not idle, it has a horrible surge and dies after sitting for more than 10 secs. Being my daily driver it's gotten old quick.
Rock777 said:
I paid $410 shipped for my used PMS. Best money I spent in a while. I tried the chip thing and that was the biggest waste of money ever. I hope that ****ing shop burns to the ground
A tweecer or a PMS are your best bets. The PMS is way more user friendly. Each unit has a few little thigns that the other can't do. Either is MORE than enough. Get your clutch and rear end posi fixed 
Just remember...your low mph can be affected by "slow shifts" or early shifts...can you comment on either?
I would set your timing at 16* and keep your stock FP (39psi) or a couple more lbs than that...and shift it quick and at 6k.
Yeah a slipping clutch can hurt your mph...my last trip to the track was almost 6mph slower (smoke the clutch BAD)...barely see the camaro I was racing in my rear view because the haze
Good Luck
I would set your timing at 16* and keep your stock FP (39psi) or a couple more lbs than that...and shift it quick and at 6k.
Yeah a slipping clutch can hurt your mph...my last trip to the track was almost 6mph slower (smoke the clutch BAD)...barely see the camaro I was racing in my rear view because the haze
Good Luck
Grn92LX said:I paid $410 shipped for my used PMS. Best money I spent in a while. I tried the chip thing and that was the biggest waste of money ever. I hope that ****ing shop burns to the ground
My rear end is being fixed ASAP. I don't really know for sure if my clutch is even going out, I was just speculating on what might be causint my low mph, although a centerforce df in probably in the near future reguardless.
