Looking for a little help with adjusting my tunnel mounted TA. It's a Spohn and a very nice piece, but I'm sure it could probably use some tweaking. The thing I'm concerned with is, what should the two small plates that hold the TA at the crossbrace be angled at, if at all? Should they aim straight up, towards the front of the car, or the back? Also I was wondering if anyone has made a set of plates that would have different holes in them to see if the front of the TA needs to be adjusted up or down? Any input would be appreciated. The car dead hooks now, but in the near future I'm adding a 125 HP shot of nitrous, so traction might be an issue. Thanks, Rick.

 

The plates that connect the mount pivot to the rod end pivot should be vertical, with the car at normal ride height. Adjusting the height of the front mount would be similar to the way the Madman TA can be adjusted.

 

Thanks for the response to how the connecting plates should be vertical. Any idea which way to go as far as the front mounting point, if I try some home made plates and a different setting? The front of the car is a little lower than the back, which is lowered just a bit.

 

Madman claims you can adjust how hard the tires hit by adjusting the height of the front mounting point. Since he has cars running 1.2x 60-fts, might be worth looking into. Check his page on the Thunder Racing site, and see if he has any info on adjusting the front height. On the other hand, BMR and Spohn have cars running similar times without the height adjustment.

 

I have been trying to understand madmans concept.......but he uses the slider vs. the links

I haven't gotten any info on how it works any better.

My buddy cut a 1.32 with a spohn arm.....

 

Iv'e checked out the picture on Thunders web site, and that is why I was wondering about making a few plates to adjust the front of the TA if needed. But when looking at the Madmad TA I just don't see anything that looks like a slider, even though the discription says it has one.

 

I don't see iut either......I put a post on ls1tech about it but brian never responded to it. I tried to call him also.....The gmhitech article does not look like it has a slider either

 

Thanks. The reason I'm wondering about playing with the front mounting point is the fact I use to be able to feel the rearend of the car come up a little under hard accelaration. The ride height is a little different now, I don't get that same feeling, but I'm pretty sure I still have the pinion angle set the same, at -2 degrees.

 

I've actually gotten into a bit of debate with Brian on the design of his TA. A buddy of mine had the Madman arm, and it ripped apart at the rear mount on a hard launch. My theory was that it did not have any provision for change in length, like the other arms have. Brian seemed to feel that the fact that his arm produced good times was adequate proof that the design was correct. Hard to argue with that logic - unless you ask the question "could it work even better with provision for change in length?". The arm in question was replaced free by Madman, with the failure ascribed to faulty welding. Brian also provided a lot of very helpful advice in getting the car's launch under control. Eventually the TA was replaced with a Spohn unit, and it turned better times with the Spohn components, but it wasn't just the TA that was swapped out by Steve Spohn. The car in question had great rear end lift with the Spohn TA.

 

Even the stock TA has a little give to it, as far as back and forth movement goes. I guess I'll just play with it till it feels right. (keep your jokes to yourself on that one) And work on getting the front end a little looser too. Thanks for everyones help, and if you have anymore please pass it on. Rick

 

Well, I was pulling a little weight out of the car today and took a look at the TA. The front mounting plates are pushed almost a half inch towards the front of the car. I guess this happened the last time I adjusted it. So hopefully once I straighten that out, I'll feel the anti-squat again.

 

More than a "little give"..... the stock TA is designed to slide back and forth in the front bushing. Movement is limited only by the length of engagement.

 

Doesn't changing the front mount (higher or lower) change the pinon angle?

 

Sure.... you would use the adjustment on the TA to put it back where it belongs.

 

Yep, and I'll wait till I'm done pulling some weight out (which will change things again) and adjust it the right way. Instead of just looking at the pinion angle.