Dyno disaster at Carlisle (well dang near)


The Voice of Reason
Jan 1, 1999
Hagerstown MD
Decided to dyno the '93 last Saturday at the Ford show. Felt pretty good about it, third time on the roller for the old girl and felt it would run pretty good with the catted H pipe vs the old X pipe I made. The H feels a whole lot stronger vs the X. Anyway, sitting next to the dyno is a mystic painted fox hatch for sale with a list of parts similiar to mine that turned out to belong to the dyno operator so I felt more confident about having him run my car.

Happened across a friend from work as I waited and he was talking to me about running the stang on the dyno and how exciting it must feel to finally see what it'll do. I replied that actually it's quite stressfull knowing you are 60 miles from home letting someone you've never met before run you car up to 6000rpm under load while hoping the whole mess doesn't come unglued... That conversation came back to haunt me the whole way home.

The first bad omen was the operator hopped in the car (on a towel to keep from getting it dirty) and didn't adjust the seat (I'm 6'8", he was about 5'10"). Remarkably he was having trouble getting it to go into reverse to get it on the ramps. On the forth attempt he made it up the ramps and I hopped in the passenger seat for the run ups. I remember asking him if he got nervous having all these people watching as he dyno'd cars and he replied that it didn't bother him at all.

After grinding the tranny a few times he got it rolling in first and then into second, got confused looking for third, but found it after hitting every gear but reverse, and finally settled into fourth (he thought). Clicked the button at 2100rpm and romped it to the floor, hit 6000rpm about two seconds later as the tires went up in smoke on the rollers and of course he was watching the screen tach and not the actual tach and it sat on the fuel limiter for at least two solid seconds (about ten minutes when it's your car).

Now I'm a pretty patient fella, but his casual reply that he must have been in second instead of fourth started to piss me off. Then he commented about the shifter being really tight and hard to get into gear. At that point I mildly asked him to adjust the f'ing seat so he could push the mother f'ing clutch all the way in so he could shift the f'ing thing without trashing the synchro's any more. Remarkably enough he didn't say a word, but adjusted the seat and got through the gears and into fourth for the pull. Funny because there were about a hundred people watching.

Things looked up as the pull was over in about nine seconds at 6k, but he didn't clutch it, just slammed the throttle shut. O the humanity. The blower overpressured and stalled spinning the belt off the pulleys and finally blowing the tube off the throttle body stalling the car. At the time I didn't notice the belt, but got the tubing locked back down, overtorquing the clamp in the process (nerves and above about patience). Readout says 355 RWHP @5000rpm and 385ftlbs @4500. Down 35hp and 5ftlbs vs the off road X pipe, but the pull times were the same.

Fire the car up for the next pull and heard the slapping of the belt segments on the radiator hoses and shut it back down. Checked it out and decided to call it a day. Rolled the car off the dyno, trimmed the rest of the damaged rib off the belt and rode it back the rest of the way on the pulleys with my pocket knife and the starter. Started the car somewhat shakily and took it back to the show field.

My confidence in the car was really shaken and I was rattled enough that I forgot to double check the hood before leaving and it came up on the latch as I was getting on the interstate for home (thank God I spend so much time making sure the hood can't get off the catch during installs). Then fifty minutes of concentrating on hearing the belt coming apart or the throttle tube coming loose had me boggled enough I ran the damn thing out of gas (didn't notice the fuel pressure drop off). Dad was behind me in his coupe so I sat and watched the traffic for a half hour while he got some fuel.

Had a fairly good weekend except for the dyno mishaps. Found parts cheap, but the food and event shirts were way overpriced.

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you cant be held accountable when something like that happens. You get so pissed sometimes, that everything is like your just dreaming it. Ive gotten excited or scared at certain stuff and its made me completely forget about odvious stuff you should do or look over on a car. It sucks.
And you paid him for that? Thanks for the heads up, you dont know who to trust. If I ever decide to put one on the dyno, I will be operating my car or they can forget it. I can get fairly close using the track. I think that company deserves a letter and owes you a refund of the services provided. That cant begin to pay for your stress. :notnice:
Just makes me appreciate my dyno shop that much more. They hook it up (that's the part of the business they know hands down) and I run it (that part of the business that I know) and everyone stays happy. :)
Ouch -- I definitely would not have been happy. :(

Overall, you still end up pretty lucky if that was all the bad stuff that happened, from the sounds of it, I'm sure he could have done much worse to the car. :nonono:
TheUser said:
I think most places require the staff to dyno the car for safety reasons? I really have no basis, but I don't hear of many people saying they get to drive their own car on the dyno.

Daggar is the exception :nice:

When I had my orange car done on a portable dyno that's how it was done. Later on, with permanent dynos I saw a lot of owners driving their own cars.

I would almost think it as being preferable. We all sign those disclaimer forms, but how could anyone try to get back at the dyno operator if they were driving their own car?
wow, that is why i HATE taking my car anywhere. ive had someone else drive my car twice at shops. first guy ground reverse over and over. i finally yelled FIRST, SECOND, THEN REVERSE! he did it once and it went in. :mad: second guy ground reverse once, then got it in, stalled the car 7 times, then smoked my clutch "trying" to get it up the lift.

i agree, ill be damned if someone else gets paid to drive my car. if they wont let me run it then i will just walk out.
I would be very upset, this is one reason that I do not want to take my car to get a tune, so far nobody has been behind the wheel of my Mach1 but my Son and me and I just can't phantom anyone doing the things that guy did to your Mustang.
86bluecobra said:
im surprised no one got hit!

Had he treated my car that way he would have been hit. :mad:

On another note. If closing the throttle backs up boost so bad that it blows the tube off the intake, you need to think about geting a blowoff valve.