esorensen

So I got the BD boost fooler today and plugged it in. With the codes cleared, there was no change. So I blocked the boost elbow and that did the trick. 32 psi. It can still get 1300*+, but before it would reach 1500*+.

I am excited to see the difference when towing. I know some timing would help, but I'd like to try it without the electronics. Some tweaking, and I think this will be quite possible and effective.

What is the mod to the stock turbo so that the wastegate opens for all 6 cylinders? Will this mod help with temps and boost?

Thanks, Eric

cumminsdriver635

The mod you can do is on the exhaust housing. You can pull the cover off, and flip the wastegate flapper over out of the way and take a big drill bit and drill through the divider in that spot so that the wastegate can gate all 6 cylinders instead of just 3.

This wont help you run any cooler. Its only needed if you have so much fuel that you cant keep the boost down, or see spikes that are higher than what you would like to see. It basically helps the turbo/your headgasket live longer by allowing the people who are WAY overfueled to keep the boost down better. It can also give a little lower temperatures by allowing you to keep the turbo at the boost range that it does the best in. But, 32-36 psi is about the best for an HX35 in my opinion, and at 32psi, you are in good shape. I would leave it right there.

Eric

esorensen

Thanks. I was aware that HOHN had done this mod a long time ago. I can't remember if he liked it or not. I need to tow and see how the heat is. Otherwise I may be looking into some electronics for some timing for additional cooling. Injectors only with the HO are REALLY NICE though.

esorensen

Ok so today I used the old hard elbow and capped off the hose so basically I have capped off the turbo. I saw ~36 psi in a 6th gear floored out pull up a hill empty! about 1300*! Thats it! Before with 24 psi it woud have been near 1600*+. I'm very happy and will hook up the camper tomorrow. The injectors aroud town are VERY tractable and only smoke off boost and it clears up with boost readily. Any electronics and the clutch wouldn't hold and neither would the head gasket. I also got rid of the stock airbox and K&N and put the BHAF back in.

HOHN

Hey Eric-- lots of good advice in this thread from a lot of "been there done that" guys.

You have a couple of issues, not any one in particular. You tall gearing, big injectors, low boost, and a reasonable amount of fuel.

The mountains of CO make dialing in a combination difficult because you want shorter gears to let the rpm come up (helps breathing to a point) but taller gears really help with the 80mph speeds that are common out there.

Here's what I would do. First, dial in your gearing. 3.42s with taller tires just is SERIOUS handicap-- no combo of turbo(s) and electronics can do much with that.

You're running 1700 rpm or so at 70mph-- you should be running 2000 to 2300 at that speed. Especially in altitude. Especially in altitude with a trailer on back. Especially in altitude with a trailer on back with larger injectors in hot weather. yada yada.

Short of a gearing swap, you have some things you can do in the meantime.

First, plug that wastegate port with a 1/8" NPT plug. You'll never be opening the gate anway. Instead, control overboost with your right foot-- keep the boost under 35psi in the thin air.

Forget resistor mods to the boost sensor. Any mild box will do the trick nicely. Try quad's little timing box-- It's a great piece.

For turbos, forget any larger single turbo. In thin air, you're giving up essential response for a smidgeon more flow that you only need .01% of the time. If your thin-air turbo plan doesn't include twins, stay with the stock charger.

If you still want to upgrade the turbo, you can upgrade to a faster-spooling charger of similar size-- something like a Garrett GT3582 or a GT3788. The GT35 is pretty close to stock sized, but spools faster. For even higher altitude, the GT32 or GT30 is where you want to be (yes, even smaller than stock!).

JMO

esorensen

Thanks Justin! I already bought the bd boost fooler and it works well especially for what it is. As far as the gearing goes, I would like to swap to 4.10s and that will get me back to "factory " rpms. I can now hit 36 psi and that suits me just fine. Gears with this combo would probably be 100% towable. found a guy here in town that will put in a set for 275 labor. Now I just need to find someone to trade with! (3.55s)

I think the catcher somputer that I got so many years ago was either defective, or I had a stored overbost code that NEVER let me run any more that 24psi EVER. Shame on me for not knowing any better. It was a stout setup though.

I think the smarty is a very nice tool. However, I'm gun shy to electronics after spending $ for the catcher, having it eventually die and buying a second ecm. I could have bought something else for the amount I'm out already.

HOHN

Beware of a low-buck gear setup. Not saying this guy's not good, just be sure he knows what he's doing. A good gear setup job takes experience, knowledge, and lots of patience. You'll never get the shim combo right the first time.

I'd go with a 4.30 gear in your truck. It's about 150rpm more than a stock 3.54 truck with stock 265 tires--- PERFECT for running in the mountains.

Randy's has Yukons in 4.30 for both the D60 and the D80.

Mike Holmen

Eric you have a six speed right? How often do you tow? If you're just occasionally towing, just run a lower gear than normal. How heavy you planning on towing? I run 33in on 3.55 gear in an auto. I tow around 15k RV, and I don't have egt's issue. My experince is that I would run a smaller sticks than bigger when towing. I rather put my foot on the floor than feather the throttle and watch the pyro all day. If you ran twins, you should be ok, just use some water/methanol spray on big hills. I've towed with mach 6's and twins, it can be done, but the first hill, the truck would be over heating. You can get the power to the road, just that cooling system is under sized for any big power. I would also look into a exhaust brake. Thrust me as the brakes get hot coming down steep grades. I've put on about 50000miles towing with my truck. Which clutch you running?

esorensen

OK so I went out today and pulled a few hills. Its been close to 90*F and I pulled just fine @65 mph in 6th! Never would that have happened before. I have to agree with HOHN and say that gears would be the final solution. It slowed down to about 60 mph up a VERY steep grade in 6th and I had at least 30-32 psi boost the whole time and egts topped out at 1225*F. If I were to have another 2-300 rpm with final drive, it wouldn't be an issue.

Mike I'm pretty sure the 6 speed has a more significant overdrive than your auto. Plus the fact that I have 35" tires just exacerbates the situation. Maybe the fact that you are 5k heavier is a wash though. The 3.8s alone are a very nice injector. I'm very impressed how well they work in spite of the lack of mechanical advantage in have in gearing while towing.

HOHN

Nope:

Auto: .69OD
6sp: .73

All else being equal, and auto in locked OD will have taller overall gearing.

JH

esorensen

Dyslexia is a horrible thing! Sorry, got 'em bakcwards!

esorensen

Any ideas on a 14cm housing? Good idea or not?

HOHN

With your current rig, I'd never go larger than a 62/71/13ss from HTT.

I'd recommend a Garrett BB for the faster response in thin air..

jmo

Mike D

Just beware of the pit falls that come with the stainless housing...cracking and wastegate puck issues.

PS Hi Justin, long time no see.

esorensen

Sorry, I was thinking hybrid 35/40.