Pros and cons of a cut and weld type AWD conversion, might need to move to OT, but it does relate to the celica.... Options

[stephen_lee]

Now THIS link started what i believed was a VERY good, and also very informative topic on a "cut and weld" type AWD conversion. Although it was a little heated, I think we need to continue this topic as it is very important to someone who is looking to do a cut and weld type conversion, skilled or not.

Now, I do believe cost and ease of mass production was a big factor in Toyota's mind when they sold the production GT4. Also weight is a consideration. So in many areas of the car, Toyota engineers may have designed a weaker than perfect setup to save cost, man/robot hours of production, and weight. Any GOOD fabricator/welder can build a system that will take a SH!T load of abuse without breaking, but an engineers JOB is to make a device thats capable of the same job, but using the least amount of materials, time to build, and over all cost/weight.

[njccmd2002]

Take my info with a grain of salt, i am not an expert but im tearing down a RA24 and also did it on a RA29.

For those who have never seen this, our cars, and most cars in the market are spotwelded mostly and couple of areas that are braced.

This allows the chassis to flex to a certain degree. The problem with fabrication, is for the experience person to know to weld right and not excessive.

Why is excessive too much? because with time the metal will fatigue and have stress fractures. I know and i saw the cut and paste with two celica chassis done. I believe it was a very good conversion, but not a very good candidate for stress or rallies, why because it will fatigue the metal very quick.

Grab a piece of metal and try to bend it several times, 10 at the most, youll suddenly see fatigue....

The best conversion will be to build a subframe that can be adapted to the rear end of the car, as this will probably be the most difficult way, but it will probably last the longest...

I never understood this until i saw my strutbar crack.. I was riding my car too hard....

[czwalga]

I welded in rear mounts, i'm going to tear the whole car down here in about another 3 weeks after my last race until january so I'll see how it handled the abuse. One rally is probably 5 years of normal abuse.

That said, my chassis doesn't flexed, all four strut towers tied in to the cage. If you push down on a corner of the car the chassis doesnt even bounce.



If Jmeyer were to rally his car, it would have a full cage in it so the point is moot. That body isn't providing the main structural part of the car.





This post has been edited by czwalga: Aug 25, 2011 - 7:41 PM

[czwalga]

This is pat richards rally car after he rolled it several times. They pieced the entire thing back together canabalizing another car. All rally cars are stitch welded along their seams becase the spots flex too much.

[njccmd2002]

forgot about the cage, you are right. Actually that is better for rally...

[94GreenLantern]

What if you get the rear subframe of a GT4 with the floor attached and you basically cut out and weld new floor in?

[99gt3sge]

living here in socal, it would be cheaper to build your own gt4 rather than buying one. i looked into it b4 and i was looking at 15,000 to bring one over from japan and i still had to register it. but the way these guys are swaping there awd stuff is bad ass!!!!! it looks awsome. if i had the money i would have these guys build me one, and that way i can still have registered as a regular celica. thats my two cents.

[czwalga]

What if you get the rear subframe of a GT4 with the floor attached and you basically cut out and weld new floor in?

Anything is possible if you do it right. That's why the thread was started. There's a group of people that think its impossible to do right and the car is going to snap in half. I will say... thats certainly not the approach for everyone.

This post has been edited by czwalga: Aug 26, 2011 - 6:41 AM