With EXTREME REGRET I post this warning.......
Newbie
Joined: May 2007
Posts: 16
Likes: 0
From: ny
OMG!! same thing happened to my turbo miata end of last year..I was making a forth gear road pull "data log" and at about 140+mph the f***ing small butterfly screw fell out of the shaft,shaft broke,throttle stuck open over 8krpm and had to shut down turning off the key...NIGHT MARE!! Mind you, my car weighs 2240 w/me and makes 625whp...It wasnt a fun ride, took a few years off my life..lol
Sorry to hear something happeed like this to someone else
BTW: this was a 75mm bbk for a 4.6 mustang TB
Sorry to hear something happeed like this to someone else
BTW: this was a 75mm bbk for a 4.6 mustang TB
The same engine will be going back in the car, I mean the exact same specs in every way. In the short time I ran it I can say it was the best engine I've ever had or built. Really is a kick in the sack that this happened.
It was for sure the screw. We see this type of thing happen a lot when something gets into one cylinder. It will get kicked around and then goes out of the cylinder it's in and sucked into another to do more damage. Seems odd but it's very common, lose a valve or anything else and it's going to end up in more than on cylinder before it's over.
Posting it sucks. I thought about just keeping it quiet and fixing the car. As usual though being open and honest about stuff is how I work. If this saves ONE other guy from the same fate it was worth making the post for the haters to enjoy.
It was for sure the screw. We see this type of thing happen a lot when something gets into one cylinder. It will get kicked around and then goes out of the cylinder it's in and sucked into another to do more damage. Seems odd but it's very common, lose a valve or anything else and it's going to end up in more than on cylinder before it's over.
Posting it sucks. I thought about just keeping it quiet and fixing the car. As usual though being open and honest about stuff is how I work. If this saves ONE other guy from the same fate it was worth making the post for the haters to enjoy.
Man that is disappointing to say the least. Though with this shared information, I can only imagine how many people will be pulling out their screws and reloctiting them in place. Thanks for the heads up.
Oh man, this is a sad day. I will be checking my screws this weekend with some other maintanence as well. Thanks for posting and helping the community once again. Hope to see it back together soon.
Excellent philosophy, stupid things like this happen, and I can attest it feels like being kicked repeatedly in the nuggets. Been there done that..
Now how to keep the haters out... Hmmm
psphinix, I know what to say, I WISH it would have happened to that 2.0LR you have in your car now! haha It kills me to change the engine this time! Oh well.......hopefully it's done for Winged Warrior and the Sport Compact race.
Thanks for taking the time to post this solemn advice. Not the first time I'd heard of this occurring but a great reminder still (checking it tonight now!). Very sorry for your loss 
Damn, I'm really sorry to hear about this David, you didn't need this. Gentlemen, if it happened Mr. Buschur, it can happen to anyone, check those throttle body plate screws! May the next engine be even better than the first!
Newbie
Joined: Sep 2009
Posts: 87
Likes: 0
From: seattle
David,
I'm pretty sure that I've seen a throttle body where the backside (protruded threaded side) of the screws were staked so that the screw can't ever rotate too far again. It might be worth the extra effort to do this in addition to the Loctite.
It will be exciting to see the new engine with the new small runner exhaust manifold on the dyno. Don't let it get you too down.
Matt
I'm pretty sure that I've seen a throttle body where the backside (protruded threaded side) of the screws were staked so that the screw can't ever rotate too far again. It might be worth the extra effort to do this in addition to the Loctite.
It will be exciting to see the new engine with the new small runner exhaust manifold on the dyno. Don't let it get you too down.
Matt
It's incredible to me how many people have had this happen to them or someone they know. Personally, until now, I've never seen it. I wish I had never seen it! haha
I just went back and stripped the head, intake and such. The head may not be as bad as I thought. We are going to drop the valves out of it and see how the seats look. The combustion chambers I think if we just put a little weld in them and do some shaping it will all clean up. I'm going to try and salvage the head rather than start over. The car just worked to damn good like it was.
Yes nucci, it's going to be exciting to see how it comes out when it's all done. I've also seen the same thing on some of the bolts before.
I just went back and stripped the head, intake and such. The head may not be as bad as I thought. We are going to drop the valves out of it and see how the seats look. The combustion chambers I think if we just put a little weld in them and do some shaping it will all clean up. I'm going to try and salvage the head rather than start over. The car just worked to damn good like it was.
Yes nucci, it's going to be exciting to see how it comes out when it's all done. I've also seen the same thing on some of the bolts before.
This exact thing happened to a friend of mine. He got lucky and the damage was pretty much only the head. The screw didnt touch the cylinder walls and it happened free reving the motor into boost so he heard the screw go in and shut down ASAP.