Ok, so a little history on the old setup and the new one. Previously, the truck had this motor, a MPT70 turbo with .68 a/r. Built 4L60e tranny and TB Stall. Race weight was about 5400 with me in it. DA was about 8000+ (track is 4800') Best pass with that combo was 12.2@110mph with a 1.76 60' running 15psi of boost.

Now for today, TVS1900 being feed by BW S475 turbo. 4L80e tranny with 10.5" Circle D single disk 2800 stall. Race weight is about 120+lbs heavier with the blower, tranny and 3/4 tank of gas. DA was about 7800'. Was running about 13psi of boost.

First pass was fresh off the drive up there, track is about a hour drive away. Truck sat about 20 min with getting teched and all then strait to the staging lanes. It was VERY heat soaked, IAT's were hi just sitting there, 130* or so, then made the pass in full street trim. Was a 13.8@100 with a 2.3 60' Leaving with about 7psi of boost. IAT's where 160* at the end of the run which I know was pulling a bunch of timing. So I went over to the convince store across the street and bought a couple bags of ice and than back to the track. I filled my intercooler reservoir with as much as I could and got the water all cooled off and and made another pass in full street trim. Was much better, 13.3@105 with a 2.0 60'. IAT's started at 95 and 120 at the end of the run. AFR was 11.5-12.2 a tad leaner then I like to run, but I didn't bring my EFILive. Timing was about 20.5.

So I decided to see what it would do in normal full race trim. I pulled the spare, tail gate, head light and cutout plate. This was right at the lunch break for the track crew so it got to set for over an hour and cool everything off really well. Was MUCH happier with this run, I left on 9psi of boost and pulled a 12.7@109 with a 1.87 60', BUT, didn't want to make the 2-3 shift and bounced off the rev limiter (6400rpm) 2-3 times and I lifted briefly so I know that cost me a couple tenths. Since I didn't have my tuning software I couldn't fix it . Made another run, but bounce off the limiter a little harder and I didn't lift, so was a bit slower. So that was my day.

Oh, and one other thing, with 13psi of boost and cutout open, had 7-8psi of back pressure BEFORE the turbo


:::Cliff Note, truck ran best of 12.7@109:::

 

id like to see what it puts down with the little bugs worked out...

 

Wow...you lost 1.1 seconds and gained 9 mpg on IAT's, and weight(not that much either). That's a pretty good day at the track!! So what do you think you'll run down at sea level? Break into the 11's?

Oh and congradulations!!

 

Good to see you got it out there. Obviously not dialed in perfectly, but I still see your point in wanting to remove the blower. For the cost of the turbo setup and having a 6,000 dollar or so intake with a pulley it's not the results you'd have been looking for. Even if you tweeked it to run 11's you wouldn't be much ahead of the single small turbo setup you had before. Those are very good times for the altitude though. Nice runs...

 

thanks for getting the times before you pull this apart. Now I want to see what the thumper runs

 

Wasn't really disappointed with that time, after all I was 2psi less boost, heaver and bounced of the rev-limiter. Add those to it and would have probable been about where I was, maybe a tad better. I think If I played with it a little more, got the boost up a bit and don't hit the rev-limiter on the shift, I could get to 11's up here.

As for what it think it will do at sealevel, I'll give you this for comparison. Ran the t70 at 15psi and ran 12.2@110 here, but when I took it to SAR in TX last Feb, ran that same 12.2@110 only with the T76 with only 10psi of boost. So should pick up a BUNCH at sea-level.

The truck is a lot more responsive on the street with the blower, but just wasn't worth the cost.

The funnest part about the whole day, is that it wasn't a normal track day. A diesel club had rented the track for a event they wanted to do with "truck" drag racing, drag towing and some stuff like that, with prizes for things like fastest "truck". I showed up with my truck and first they were like "this is for diesels only!" "Your a GASSER!" I was like WTF???, radio only said "trucks" not "diesel ONLY trucks" After me and another guy with a 2wd RCSB with a camed 5.3 spraying a 175 shot fought with them for a while and they realized they only had about 15 other truck at the time they let us run our "gassers", but for TIME ONLY, BUT still had to pay the $50 entry fee. I had already driven the hour to get there, so I did it any way.

Everyone loved my truck, but were pissed when I "smoked" ALL there diesels asses . I had the fasted truck, but they wouldn't give me the prize cuz I was a "gasser" and not a "diesel", lame

 

very cool none the less. you set out and accomplished what others feared attempt.

edit: lame diesel drivers suck....no respect!

 

they should double your payout for being a gasser! go ahead and pull off that heat sink air restricter. my truck runs 12.80's up here with 10 psi and 16 deg. timing. and thats at 5800 ft. you should be low low 12's with your setup and turbo only!

 

No, your WRONG!!!





I should be high 11's!!!