Need fast input on twins, towing or street/strip?

[Glacier Diesel Power]

Here's what I'm up against. Piers is installing twins on my truck in a couple of weeks. Today he mentioned that he could also do towing twins for the 3rd Gens. Reading his site I didn't realize this. Thought they were only for the 1st and 2nd gens. I was running the new TST program which doesn't really come on until 1800 rpm so we decided that the 35 would be a better choice for me than the 40. This is where thing get a little interesting.

Today I received a new TST that has been flashed with the twins program. The original one I was running started to add fuel at 10 lbs and wasn't all in until 34 lbs. This is why I thought the 35 might be a better choice. The new box is an animal! It's starts adding fuel at 1 lb (yes, ONE!) and is all in by 12 lbs. Bottom end fuel is no longer a problem! The third Gen's don't fuel until they see boost but this new box makes my truck feel like my turned up 97 when it came out of the hole.

This is where I get confused on the nature of twins. Since I now have fuel almost straight off idle would I be better off with the 35 to cool the egt almost instantly or would the 40 spool quickly enough with the extra bottom end fueling to not be a problem. What I'm worried about is hitting the 35 with too much in the way of instant egt's and drive pressure and taking out the shaft and bushings.

I don't drag race or pull but I play hard on the street and tow quite a bit. One more question. Can you bark twins? Never heard it mentioned.


Richard