cheap turbo upgrade

[TFaucette]

i would like to add more performance to my first gen which was manufactured on 9/89, what size exhaust housing do i have stock, and what would be a good upgrade. i've heard of putting an hx35 wastegated houssing on. also i've heard of throwing on a complete third gen he turbo on all i would have to do is fab up a boost tube. the full power screw is not yet turned up but i have rotated my fuel pin and turned up the ac star wheel, not sure how the stock exhuast housing and being non-intercooled likes it, although i'm sure the stock exhasut housing is huge and dosen't create high egt's but what kind of pressures doese the stock turbo capble of and efieceint at. i do not yet have a egt or boost gauge but plan on it but however do not plan on a charge air cooler.

 

[fox]

First put a pyrometer on it and see where it is.

I would guess that a HX35/12wg would be a great up grade.

i did a 91. 5 and he loves it.

 

[RSchwarzli]

First, get an EGT and Boost gauge. You will not know if you are doing damage or what your base line is if you do not do those first.



THEN the turbo comes.



I would suggest a HX35 with your current exhaust housing if you want cheap. Thats what I run. Love it. It is also a 90 model. Was built 10/89.



Should you want a bit more, go to a smaller (like 16) housing. 14 or 12 might be a bit small if you plan to tow though. EGT goes down 150 F (if memory serves) for every 2 points you go up in housing size. IE 14-16. etc. So if you are at a 12... . might be a bit warm but she will spool great!

 

[TFaucette]

i love the way the old h1c sounds though. what will i get out of using the hx35 compressor over the h1c, what size housings are the hx35's, and if wastegated i guess a smaller housing doesen't affect egt's?

 

[Bob Beauchaine]

I have had a PDRHX35 and a 14wg hot side for quite a few years and this setup has served me well, under all conditions. Running up Cabbage Hill in eastern Oregon I could not get my Snow W/M to come on do to high temps. My EGT guage would not go over 950.



Bob

 

[NIsaacs]

Unless you are looking for huge power gains in the future, I would stay with the stock turbo. It has the #18 turbine housing from the factory. In '91. 5 they used the #21, a poor choice, then due to customer complaints went back to the #18 in '92. 5. If you live at high elevation, you might want a #16 or even a #14 for quicker spool. Your stock turbo as is, will support 240 hp/ 600 tq. no problem and spools quick with the short distance of no intercooler.



Nick

 

[ENafziger]

also i've heard of throwing on a complete third gen he turbo on all i would have to do is fab up a boost tube.

I think a 3rd gen turbo swap is a great choice!!! It's a Holset 351cw. However, there's more to it than just fabbing up a boost tube. That is one part of it. Some other things that need done are:

- Do something with the electronic wastegate. I removed mine, welded an 1/8" pipe bung, and bought an adjustable boost elbow to thread in.
- You'll need to get the right size exhaust flange to mate up with the 351... it's an odd size.
- You'll need to clock the compressor to allow the wastegate to clear the exhaust manifold as it works back and forth
- Slight modifications to the oil lines
- To get the most benefit, you'll want to port the wastegate hole a little bigger. I drilled mine out with a 1" bit, and it turned out slightly larger than that... about perfect.

--Eric

 

[JLEONARD]

I would stay with the stock turbo

Thai is not good advice. The non intercooled engines have what has been called a "baby H1C". It has a very small diameter compressor turbine.

I ended up running a 16 cm exhaust housing which really reduced turbo lag from the stock 18 cm. I then installed a compressor wheel and housing from a 94 H1C which was significantly larger, then made up a larger crossover pipe. It was a really good drivable combination without going crazy. EGT was never a problem.

 

[TFaucette]

- To get the most benefit, you'll want to port the wastegate hole a little bigger. I drilled mine out with a 1" bit, and it turned out slightly larger than that... about perfect.



should i port the wastegate hole on my third gen? egt's skyrocket on that thing

 

[TFaucette]

my buddy broke a shaft in his 01 H. O. and replaced it with a silver bullet 64, can his exhuast housing bolt onto my h1c. i am guessing that is a hy35, which i heard is the same as an early third gen he341

 

[fox]

The 2001 and 02 had a hx35 not the hy9. Hy9 was used in those years on the auto trucks and those were not ho's.

To break a shaft on those he must of been barking it, and that is ussually from trying to bark it.

Best bet at the power you are at is a hx 35 with either a 12 or 14 exhaust housing.

 

[TFaucette]

so an 01 6 speed H. O. is an hx35 turbo? i was actually with him when it happened, we were accelerating onto the highway pulling an old 656 international, i think it is just a factor of the programer turned up and over 300k on the turbo that caused it, the edge attitude reported 41 psi as highest pressure which i assume is way oversppeding it.

 

[NIsaacs]

It's not good advice?? It's all factual, just a different suggestion then you, another option. I am a big fan of, "if it ain't broke don't fix it", I am also thrifty, if it is not needed I don't spend the time or money.



The OP didn't say he was after big power. The three trucks in my sig. are all fuel modified with stock turbos, intakes and exhaust. They are all old yet very dependable and must have usable power to tow. The Ford spent years in the log woods hauling stupid sized loads. The '91 does have a #16, the factory #21 did not like 6,000 ft where I live.



On the dyno, the Ford has 241 hp/644 tq at 25 psi boost, the '91 has 263 hp/708 tq at 28 psi boost and the '01 has 335 hp/852 tq at 32 psi boost.



Nick

 

[cerberusiam]

should i port the wastegate hole on my third gen? egt's skyrocket on that thing

There is a lot more going on there than just the WG. Porting the WG will nothing for your EGT's, thats not how it works.



An HX35 on a 12cm housing is a good upgrade but Iwouldn't touch one with a broken shaft unless its rebuilt. You need a bigger compressor wheel along with the housing to make a difference.



If you want a project, an HE351VE works great on a 6BT.

 

[ENafziger]

There is a lot more going on there than just the WG. Porting the WG will nothing for your EGT's, thats not how it works.

I should've been more clear. The above is right. Porting the WG doesn't lower EGTs. In fact, anytime you are "waste gating" exhaust, you are losing usable power and efficiency. The reason for porting the WG is to keep drive pressure down when overdriving the turbo... particularly with 9cm housing. The benefit is you get a great spooling turbo that will handle 300 - 350 hp and offer tremendous driveability and towing.

--Eric

 

[cerberusiam]

The reason for porting the WG is to keep drive pressure down when overdriving the turbo... particularly with 9cm housing.

Drive pressure really has nothing to do with the WG port either.



DP is a function of the exhaust housing size\flow to the amount of exhaust trying to go thru it. If you smooth and port the exhaust housing you can influence the DP but the WG port is not going to make much of a difference. Once it opens DP is going to drop anyway becuase the flow is venting thru the WG and the housing.



The only reason I can think of to work on the WG housing is to clean it up so the gate actualy works correctly and doesn't hang closed or open.

 

[ENafziger]

Drive pressure really has nothing to do with the WG port either.

DP is a function of the exhaust housing size\flow to the amount of exhaust trying to go thru it. If you smooth and port the exhaust housing you can influence the DP but the WG port is not going to make much of a difference. Once it opens DP is going to drop anyway becuase the flow is venting thru the WG and the housing.

The only reason I can think of to work on the WG housing is to clean it up so the gate actualy works correctly and doesn't hang closed or open. <!-- google_ad_section_end --> <!-- / message --><!-- BEGIN TEMPLATE: ad_showthread_firstpost_sig --><!-- END TEMPLATE: ad_showthread_firstpost_sig --><!-- sig -->

I don't think I agree with this. Sure, exhaust housing size has something to do with backpressure, but the main restriction in the exhaust flow path is the exhaust pinwheel. Since the compressor wheel and exhaust wheel are directly connected by a shaft, it takes a lot of pressure to drive the exhaust side when you start pushing the turbo out of it's efficiency range. When this occurs, drive pressure to boost ratio can climb to 1. 4:1 or higher.

When the wastegate opens, a portion of the exhaust flow bypasses the main restriction (exhaust pinwheel) and expands into the exhaust downstream of the turbocharger. The stock wastegate port is ~ 0. 750" diameter. By opening the port up to 1 1/16", you effectively open increase this "bypass" diameter from 0. 442 in2 to 0. 887 in2. Now obviously, the wastegate flapper doesn't open a full 90°, but effective flow area is doubled by drilling out the hole slightly.

--Eric

 

[cerberusiam]

When the wastegate opens, a portion of the exhaust flow bypasses the main restriction (exhaust pinwheel) and expands into the exhaust downstream of the turbocharger.

What do you think happens to DP when the WG opens? If you add an additional path for the exhaust to flow to what happens to DP?



Unless your seriously over fueling, bypassing the turbine will drop DP and boost both.



Rather than opening the WG channel, I think smoothing and opening the actual exhaust port is going to do more for reducing DP while retaining boost than anything.

 

[ENafziger]

What do you think happens to DP when the WG opens? If you add an additional path for the exhaust to flow to what happens to DP?

Unless your seriously over fueling, bypassing the turbine will drop DP and boost both.

When the WG opens, drive pressure instantly drops!!! The point of the wastegate is to keep turbine speed (and thus DP) in check!

That's why I originally said:

The reason for porting the WG is to keep drive pressure down when overdriving the turbo... particularly with 9cm housing.

You said,

Drive pressure really has nothing to do with the WG port either.

But, as I understand it, the WG has everything to do with controlling drive pressure. The wastegate opens, DP goes down.

Am I missing something?

 

[cerberusiam]

But, as I understand it, the WG has everything to do with controlling drive pressure. The wastegate opens, DP goes down.

The WG opening will drop the DP because its an alternate route, but, thats not what the function of the WG is intended for.



The WG is intended to control the boost and keep the turbine speed in check. To control DP you need to match the turbine flow to the existing exhuast flow. You can control DP by also matching instead of opening the WG.



You don't really need to open up the WG port as the stock port will limit boost and DP just fine when it opens. The work needs done on the housing to make the flow better when the WG is closed.