[TR] racing a tr4

emanteno at comcast.net emanteno at comcast.net
Thu Sep 13 20:54:28 MDT 2007


-------------- Original message -------------- 
From: "Mark Vaden" <markvaden at gmail.com> 

> What are the most important modifications for safety? And after that what are the must 
> do modifications for performance? 

The most important thing to do with the TR4 is to have the rear axles converted to Ford axles via the Southwick conversion. The stock axles will not hold up to the rigors of racing and one will break, a wheel will fall off, the axle tube will dig into the ground, and you will most likely end up upside down. The Southwick conversion was designed by TR4 vintage racer Jack Drews, along with machinist Bob Southwick, and uses the stock diff and axle assembly modified to use 1 piece Ford axles rated to take over 300 hp. Jack got involved when his first TR4 was destroyed after an axle failure at over 100 mph, which resulted in 3 rollovers. In the years since this conversion was created, we haven't heard of 1 failure.
You can contact Jack to arrange for a conversion at 
vinttr4 at geneseo.net
Don't expect an answer from him right away, he's at Road America this weekend.
After that, I would reinforce the front hubs and/or buy the aluminum billet hubs from Southwick if he still has any available, and buy the front axle and bearing spacer kit. You'll be able to go a lot faster if you can keep the wheels on the car. 

Irv Korey
74 TR6 CF22767U
Highland Park, IL


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