mcfarlnd

iTrader: (15)

im not doubting you and i understand what your saying but, why would the truck tb open more than the the car tb as the op stated if they are both angled the same way on the intakes?

CI DENALI

Firstly, the GM trucks don't have a 90mm Throttle Body, it's actually an 87mm. Secondly, the truck throttle body has a huge ridge at the bottom of the TB in front of the blade that is a very apparent WOT flow restriction. Thirdly, The truck (87mm) TB blade rotates in the opposite different direction from the Car 90mm TB. I have looked at both side by side with the TB harness connected and the throttle floored and also with both mounted on the truck intake and the Car 90mm TB is DEFINITELY NOT opening fully. I don't know whether it's 83% or 85 % or 89%, But it is NOT going WOT. As far as I am aware, WOT is when the blade is perfectly parallel to the throat of the TB right? Am I stupid or something? I've looked down enough carbs and throttle bodies over the years to know when one isn't opening fully!
Besides, I've communicated with DR. X and they have confirmed that there is a difference between the two and that they were working on a harness, but the lack of demand caused them to shelve their prototype. Also, if you look at the install instructions on their website, it is clear that there is a difference between the truck 87mm and the car 90mm throttle bodies, since you have to cut two looped wires on their harness for the the car TB, whereas you don't for the Truck TB.
Maybe there just isn't enough people out there who actually checked to see if their 90mm TB is actually physically going to WOT on their trucks. I did, and I know mine doesn't. AND, worse yet, there doesn't seem to be a fix.

skyhighsami

iTrader: (8)

I hope my wife isn't thinking the same thing....

skyhighsami

iTrader: (8)

Are you saying even the stock one doesn't go WOT? If the stock one does why not just take your dremel and smooth the ridge out blocking flow until a new harness comes out and offers the fix

CI DENALI

The stock one does go full WOT. I am going to port it but I want to do a couple of baseline runs first, N/A and w/ the Nitrous, so I can see what difference, if any, it makes.

CI DENALI

Here's what the two throttle bodies look like side by side. You can see the large ridge on the Truck TB (the one with the gold throttle blade).
Note also that the blades rotate in different directions (NB: one of the photos shows the truck TB upside down).

mcfarlnd

iTrader: (15)

not to be a smart *** but, couldnt you just bolt the car throttle body upside down to make the throttle blade open the correct way? i know it doesnt fix the 100%wot but if the bolt pattern is the same and you have clearance, its a thought. what wires on the tb are coorelated to the ones you cut for the dr.x harness?

Just Enough

CI Denali, After seeing your pictures I noticed that your throttle body has the truck ridges, what year 6.2 do you have. Here are pictures of my 09 TB without the ridges. It measures 3.440 inches across the narrowest point (old school venturi) in both directions, top to bottom and side to side. What are you inside diameter smallest dimensions?

CI DENALI

I have the '08. Thanks for the info and the photos. I haven't measured it as yet but mine does look a lot different. The '09 looks much less restrictive. I'm going to try to order one of those. That may be the answer. For now I'm just going to port mine this weekend and try it.

CI DENALI

That might have helped but it can't physically bolt up, since the throttle motor hits the alternator.
I can't remember exactly, but there are two looped wires on the dr. X harness that you have to cut to run the 90mm. If you look at the install instructions on their website you'll see what I'm talking about. I'm still convinced that there has to be an easy tuning/voltage adjustment fix out there somewhere...