Question of ballance? Flywheel.

Howard Jones · 06-12-03, 01:04 PM

I have been thinking more and more about a question that came up elsewhere on the forum and I'm wondering if you chaps across the pond might have some thoughts on this.
I have a GTD with the orginal flywheel, out of a V6 granada I think, and a new SVO 302 cratemotor. Now the crank ballance on the motor is the 50oz spec and I have installed a 50oz dampner as required. But I did'nt think about it and put the rest of the powertrain together, R21T, rebuilt stock clutch upgraded by centerforce, and everthing seams to work fine. The question is, is the flywheel ballanced to something other than the 50oz standard that this motor is or is this even a question to worry about. I have a flywheel that came with the motor from ford, it is too big to fit in the renault bellhousing, but I could use it to "match" ballance the smaller flywheel I have in the car if necessary. What do you guys do with the GTD kit flywheels when you use them with a 50oz 302?
Buy the way the upgrade centerforce clutch is working fine with the power this motor has, about 350-375hp and I would like to keep it.
What do you GTD guys think?

dave harris · 06-12-03, 01:42 PM

I have seen this question covered on other forums and the majority opinion for high performance / race motors has always been: Since Ford rotating assemblies are externally balanced as a "unit" (i.e. each part is not balanced to zero itself), if you change parts from that assembly you should rebalance it. If you can't rebalance the whole assembly then, at a minimum, you should have the replaced part "match balanced" to the old part.

Howard Jones · 06-12-03, 01:48 PM

I guess I was wondering what the ballance factor of the V6 flywheel I have installed is? Maybe 28oz like a older 289? I will more than likely have the V6 flywheel "match" ballanced to the V8 wheel that came from Ford with my motor but I would like to get as much information on this posted here for future "searches" as possible.

Chris Melia · 06-12-03, 02:46 PM

Hi Howard
I think you have two options
1 balance all the rotating assembly.
2 Use the larger Ford fly wheel and change the bell housing. Tornado or Mach 1 Transmissions can supply a Renault to Ford housing that takes the 152 tooth Mustang fly wheel.
The choice is yours but you won't get away with a V6 flywheel balanced for a 28 oz motor on a 50 oz motor.

Regards
Chris.

Frank Catt · 06-12-03, 02:55 PM

Hi Howard, we have built many Ford engines for the GTDs, and without exception there is only one way to do it without future problems, strip the motor and balance the whole rotating/reciprocating assembly, with the flywhhel and clutch. Frank

Iron Sheik · 06-12-03, 04:29 PM

Howard,

I have the same motor as you have (and flywheel, clutch...). Call or e-mail me, if you like.

Howard Jones · 06-13-03, 01:12 AM

Chris, So the V6 wheels are 28oz balance factor? Hmmmm you learn something every day. Ok Thanks.

Chris Melia · 06-13-03, 03:10 AM

Howard

the V6 fly wheels were modified to the Ford Bolt pattern at the crank then balanced for the common 28 oz motor.
I made my own fly wheel from steel and had it balanced as an assembly for my 28 oz motor. It needed over 70 grams adding and a few lightening holes drilling to achieve balance.
There is just no compromise on this.

Regards
Chris

Howard Jones · 06-13-03, 12:15 PM

Thanks Chris, gonna take it apart and get the v6 wheel matched to the v8 wheel that came with the motor. At least now, because of all the advice this group has given me, I will not be wasting my time. I never have a problem doing the work correctly, it's just that there are so many people that have a lot of very misinformed or incomplete advice. Thanks again! Your friend, Howard Jones.

I drove over to my drag race buddy's shop , mid 6 sec/200mph pro mod car, and talked to him about this and he pretty much said the same thing you did Chris, He wants me to stop running the motor much beyond idle speed and bring both flywheels to him so that he can rebalance the V6 wheel to 50oz standard. He wants to check the V8 wheel first just to make sure of what it is. He told me this is a common thing and the added weight goes on the same spot on the flywheel. He also told me not to try and add weight on the clutch presure plate as some less informed people have tried as this will not work and is asking for a blown up clutch presure plate. All in all this rebalance to new standard isn't a problem. There are also a lot of 50oz wheels that have weight removed to to put on 28oz motors also. This is easier because weight is just removed. This seams to be the bottom of this issue. The GT40 forum has solved another one!! Good Job Guys!!