Finally hurt my 7m at over 700 whp.

X-man

member
Dec 5, 2005
309
0
0
Pulaski,Va
Finally hurt my 7m at over 700 whp.



http://www.youtube.com/watch?v=RC8eaRTHYLY

These are the results of a tuning session on 9-9-12. Still stock bottom end with a stock heads. New additions were 272 BC cams, Titan gears, 2150 cc FIC injectors, ARP head studs, Magna Fuel 750 pump and regulator and 2 no#6 return lines to regulator and a no#10 return to the tank. Boost was set at 26 psi and this was on E85.

Engine never dropped oil psi and has no blowby beyond normal and the water temp never got higher than normal on any of the pulls. Four runs in I picked up a vibration when letting off after the pull and on the last two runs power started falling. I drove the car home and it ran fine just alittle noisy over 3000 rpm.

I was able to make the same power it took me 28 psi to do with stock cams but I had to turn the engine 8000 rpm to hit peak power. Not sure what has come loose as nothing vibrated on the way home but I have a forged bottom end to go in the car so as soon as I finish my GTO I will start back on the Supra.
 

suprahero

naughty by nature
Staff member
Aug 26, 2005
14,971
0
36
53
Roll Tide
Good job. It's been a while since I've seen any supra videos posted up. Thanks for sharing. I'll be interested to see what has happened causing the vibration like that.
 

X-man

member
Dec 5, 2005
309
0
0
Pulaski,Va
I actually thought the flywheel had broke bolts or came loose. It would just sit there and shake when the car was in neutral coming down with the dyno brake. We initially thought the tires or rims where I had it cranked down on the dyno but everything looked true. It is possible I bent a connecting rod as I seem to remember something about the guy with the real nice MKIII from Austrailia bent some over 700 whp.
 
Last edited:

te72

Classifieds Moderator
Staff member
Mar 26, 2006
6,603
2
38
40
WHYoming
I've seen flywheel bolts back out before, causing some issues. Anyway, you'll have to update us when you figure out what it is that cause the vibrations. Sounds like an impressive setup. :)
 

X-man

member
Dec 5, 2005
309
0
0
Pulaski,Va
Chambers;1874314 said:
Have you checked your drive train? Driveshaft, carrier bearing, u-joints, rear, wheel bearings, rear brakes, etc...

I have had out of round rims show up on the dyno and cause vibrations but it is usually through the whole pull and worse at higher speeds. I have a one piece driveshaft so no carrier bearing to worry about.

I have not taken it easy on the car since I did the 753 whp in 2008. It has been drag raced and driven around on the street at 27 psi on C16. Race fuel has just gotten so rediculously expensive that I changed my drag truck and my Supra to E85 but I had no illusions of this engine staying together at these power levels forever but it sure has been a tough 7m.
 

Hotwheelsjr

New Member
May 22, 2011
146
0
0
Surprise AZ
X-man;1874424 said:
I have had out of round rims show up on the dyno and cause vibrations but it is usually through the whole pull and worse at higher speeds. I have a one piece driveshaft so no carrier bearing to worry about.

I have not taken it easy on the car since I did the 753 whp in 2008. It has been drag raced and driven around on the street at 27 psi on C16. Race fuel has just gotten so rediculously expensive that I changed my drag truck and my Supra to E85 but I had no illusions of this engine staying together at these power levels forever but it sure has been a tough 7m.

Ya -- people don't realize how strong the 7M can be. 27 psi is quite impressive on a stock bottom end. Folks usually wind up melting pistons before destroying a crank or rods...I've never seen a windowed 7M.
 

te72

Classifieds Moderator
Staff member
Mar 26, 2006
6,603
2
38
40
WHYoming
X-man;1874424 said:
...I had no illusions of this engine staying together at these power levels forever but it sure has been a tough 7m.
Should go with a WHATJZ swap. :rofl:

Seriously man, for a stock bottom end, you've proved that it is more in the tune than the parts if you have a good engine to start with. I figured this was a one time thing, but if you've been using and abusing it all these years... well done!
 

Another MkIII

Member
Feb 22, 2009
697
0
16
Chicago
Hotwheelsjr;1874518 said:
Ya -- people don't realize how strong the 7M can be. 27 psi is quite impressive on a stock bottom end. Folks usually wind up melting pistons before destroying a crank or rods...I've never seen a windowed 7M.
I have seen one...it was in my car when I bought it. :D
-AM3