Advice / Sanity Check

[jaluhn83]

Looking for some opinions:

Right now the motor I've got was rebuilt ~30k miles ago and fitted with a custom turbo setup based on a Banks WG turbo. I am fairly happy with the power improvement over the non turbo, but would like to add a bit, especially low end. I'm only making ~5 psi at 2000 rpm and 8-9psi @ 2750 which seems low but we have not been able to figure out why. My suspicion is either a defect in the turbo or losses in the cobbled up exhaust piping I have.

The main goal is to increase low end (1500-2000) rpm torque as much as possible without compromising durability or spending too much money.

I am going to have to pull the motor and replace pistons soon to rectify what seems to be a loose wrist pin and because some of the pistons have damage from a dropped valve right after the first rebuild. I'm planning to have them shaved 0.015" (I calculate this should give ~20:1 cr) and have the crowns ceramic coated. The motor already has head studs, and I'm planning to put one of Russ' torque cams in as well.

I'm also planning to install a proper turbo up-pipe setup, hopefully off a Banks turbo kit if I can find one. The piping I have now is sort of redneck engineered and probably flows poorly, in addition to overheating the clutch slave and locating the turbo too high and fwd. The plan is then to install a larger turbo, possibly a HX/HY35 and intercooler.

So, questions:

1) Any other suggestions while I've got the motor out? I'm not expecting to need any replacement parts other than pistons. The heads were done recently with new exhaust valves. Is there any valve to ceramic coating the valve heads?

2) I've got a line on a HY35 turbo off a 01 cummins. What can I expect from this turbo? I know it's pretty small as far as the holsets go, but since I'm going for low end that should be ok provided it doesn't choke too badly at higher rpm.

3) How well does the HY/X35 fit on our motors? Any major issues?

4) Anyone have experience with "Speed Pro" brand pistons? There's a set on ebay that would work for me for pretty cheap but I want to make sure they're not chinese junk. From what I've found this is a Federal Mogul brand but I've not seen them before.

This truck is mainly used for towing, mostly around 15k gvw with my horse trailer. I'm not looking to make crazy power and don't really care about numbers, the main goal is getting the rig where I want to go reliably and without bogging down too much.

Thanks,
~John

 

[jaluhn83]

And one more.... are the HY35 and HX35 the same housing size / mounts? They look like it to me. The reason I ask is to see what it would take to put a HX35 in place of the HY35 should I wind up wanting to upgrade later.

 

[icanfixall]

Is the Banks turbo a sidewinder type setup. If so they still sell the crossover pipes that connects to the exhaust Y collecter. Look over all the exhaust joints for any black soot. If any are found those are leaks. Turning up the fuel will make more boost because your making more exhaust heat. Do this only if there is a pyro installed. Any fuel turn up will make more boost pressure. It takes heat which is turned into power to spin the turbo more strongly so the boost goes up accordingly. Can't answer the piston issue. Adding thr typ4 cam will definetly give you more bottom end torque... Everyone thats installed them speaks of this. Before removing the rods plastigage them first. That way you will know if the rod bearings are still ok. Do the mains too. Your that far into it the idea is to not being going back in again soon. Look closely at the main seals. If they have worn a groove replace them now before they leak in another 15 or 20 thousands miles..

 

[FordGuy100]

The HY35 flows more air, but the housing is smaller (9cm) and I feel that is to small for a 6.9-7.3l engine...especially if you are towing. Backpressure will be higher, and so will EGT's. Upgrade to at least a 12cm housing, 14-16cm would be better.

 

[Devon Harley]

The above is correct its a small turbo an will spool very well but back pressure will be high as well as egt's will rise quite high. An easy fix is a new exhaust housing off over ebay. I would go with a 14mm or 16mm just because it will loose alot of flow up top an will loose boost when intercooled so you need to off set it some how.

 

[gingrass179]

ya the hy only being a 9cm housing will choke your poor girl up the hx you can get it in a 12-14cm housing which will be better for egts and gas mileage...the hx on my truck i see 5psi by 1500 and 12ish by 2000 and then it lights hard up to 18 but thats when im out of fuel i think the hx is double the bottom end the 093 setup gave me and the 093 gave me more than double the n/a...well you get the point

 

[jaluhn83]

Okay, roger.

I don't have any stock exhaust system parts - only thing Banks on the truck is the turbo and crankcase vent adapter. I'm looking for a Sidewinder y-collector. Would like to find a crossover pipe, but I can fab one pretty easily. What I have now is clunky but no leaks. I've got plenty of fuel. My best guess is that I've got the wrong turbine housing. The turbo is a ebay special that was solf new but missing the wg actuator and turbine heat shield. I subsequently discovered that the wastegate port was about 2 mm too large for the valve which at the time I thought was a matter of a machining oops, but now I wonder if maybe it's an entirely wrong housing. (too large of a/r?) The wg problem I corrected by machining a press fit seat insert and I don't think I'm getting leakage past that. My guess is the turbo was an OEM QA reject that somehow made it out of the factory on the side.

I'm replacing all the seals and gaskets for gp while it's apart and will assuredly check all the bearings.

Any idea of numbers for the HY35? The consensus is that it's too small, got it, but what can I expect out of it without excessive egts? Say at 2000 rpm. Can anyone confirm that the HY & HX mounts are the same? My plan is to put the HY on and then assuming it's the same I can slap a HX on there without much problem later. If it is different than it's a different ball of yarn since I'll have to redo fab work over again.

I really don't care much about performance over 2500 rpm, or super high boost. What it boils down to at the moment is if the HY will give me anything over the half functional TE06 I have now, and how badly that's going to restrict the motor.

Devon, are the HY & HX housings the same? I've seen HX housings, but nothing for a HY35 and I'm pretty sure the turbine is different between the 2.

 

[jaluhn83]

Are there any valve spring upgrades for idis? Would it be worthwhile given I'm running higher boost as well as an exhaust brake?