Never run in D. Always run in 3.

 

I've heard to always run it in 3rd, however I'm not sure why. I've run mine in Drive and have my tow haul button engaged and shift points tuned that way.

Now that you have a dyno graph, you can actually do some math and figure out what your ideal shift points are. Do some digging on the interwebs on how to calculate ideal shift points. Using the torque curve (tq and rpm) you'll want to figure out what the trucks acceleration is in each gear, and then plot them on a graph (not needed but helpful). When the trucks acceleration in 1st gear at high rpm drops below the trucks acceleration at the corresponding mph/rpm in 2nd gear, you've found your shift point....something to that effect!

Hope to see you reporting some badass track times shortly!

 

Selector in 3rd engages the overrun clutches I believe, and you certainly dont want to try to shift to 4th under power unless your trans is built for that!

 

Leaving it in Drive will have all the power running through the roller clutch only. That part is very weak and can explode and send metal through the transmission.

You need to run a 4L80e in D3 so both the roller clutch and overrun clutches are engaged.

 

I never knew and have made lots of passes in D, I must have gotten lucky or whatever damage I did hasn't made itself apparent. I'll be sure to make future passes in 3rd. What are the differences in regards to their ability to handle more power (if any) between an 85e and an 80e? Mine came out of an 05 8.1 Suburban so it's an 85 but I'm not sure if that means it's stronger.

 

All these summer time project updates everyone is posting have really made me excited to hit the track. In the meantime, I've been taking care of some much needed maintenance items. Other than that, I've just been DD'ing the truck as usual and keeping my eye on Craigslist for 265/60/18 tires as they don't seen to last very long. I did score a sweet set of Michelins (one had a patch but holds air fine) for the unbelievable price of $40 for the set of 4. Used tire shop where I get my tires mounted says he usually gets $100 per tire for Michelin's since they're an OEM size and everyone wants them. Here is my growing stack of used tires I collect, along with my spare that I took off:



I removed the Cal Tracs bars themselves temporarily, as the ride was simply too punishing on a day to day basis. A few months ago I did a number on my back. I think I was dragging a heavy pallet around, which I will never do again. Had to get an epidural shot which completely helped, but the jarring ride in the rear of the truck simply did not feel good. Maybe I never noticed it before, but even with no preload on the bars, the ride in the back was seriously like a covered wagon. Removing the bars has made the ride normal and compliant again. And strangely enough, the truck is way more controllable when the rear tires light up. It will fishtail smoothly without jerking and catching itself, but of course it squats way more. I'll reinstall them at the track and put the same 1 full turn of preload on them. I also threw on a pair of Monroe Sensatrac shocks for the ultimate ride comfort lol. It will only take me 20 mins to swap the Calvert shocks before I go to the track.



I also needed to fix two leaks. The passenger side IFS axle seal had started to leak pretty good. Enough so that I didn't want to put it in 4WD without fixing it. I pulled the IFS case half and did a new needle bearing and seal on that side only. Kinda a pita but seems to have worked.

I also had a pretty decent drip coming from the 4L85E bulkhead connector that left the fluid a little low every 30 days or so. I was sick of putting fluid in it regularly so I bought a new valve body harness off ebay for $40 bux. I've read this is a common problem. It required me to drop the trans crossmember, support the transfer case, remove shift cable, drop pan, etc in order to install the new harness. The bulkhead connector has several tabs that hold it into the case. After 20 mins of struggling to compress those, I said f*ck it and put a punch into the middle of the connector and gave it a whack and sure enough it pushed through.



The new Trick intercooler is working great. I put a light coat of flat black on it for the stealth factor, so it's totally undetectable. I can cruise around and it's just another truck with a Flowmaster and 4" tailpipe. The slight lope and ethanol smell at idle is the only thing that gives it away. You'd really have to be a car guy to know though.



At the end of the day, it's just another chebby with wheels and shackles . I'm stoked on it though, it's never ran better and off idle response is crisper than stock. Overall the driveability is nailed and it's a reliable driver that gets 15mpg on the freeway, and 11 mixed (on corn), which isn't too bad considering the price of E85 here is ~$2.20 and the price of 91 is ~$2.90. So considering E85 is 22% cheaper than 91, I'm getting roughly 19mpg freeway/ 14mpg around town if I was on gasoline.

 

yep in that pic you can not see the inter cooler at all..

 

Glad you are liking the driveability much better!

 

It made a huge difference no doubt

 

Well I never would have guessed it, but my Walbro 450 F90000267 went out. I was driving through town and the idle started to fluctuate like it wanted to stall. I took a glance at the gauges and sure enough the fuel pressure was going 17psi - 26psi. I was able to limp it back but the pump was on its last legs. As soon as I shut it off, that was it. Zero fuel pressure and wouldn't restart. I am running E85 with a BAP so it's possible the BAP shortened the lifespan of the pump. Either way these are cheap pumps and I had been meaning to install the F90000274 (higher bypass) pump.

I think the dual pump will actually require a retune (anyone know?) so I'd like to give the F90000274 pump + BAP a shot for the time being. Takes me 30 mins to raise the bed but start to finish the pump swap is still a 2hr job at least.