Stock 3rd gen turbo as seconcondary in twins?

cyric

cyric

Tinkerer
Joined
Jun 8, 2007
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69
I was just wondering if a stocker of an 04.5 will make a good secondary charger in twins. I can get one cheap and wanted some opinions before I spent the money. I realize it has a small turbine housing, but an external gate should take care of that. Any thoughts would be appreciated. I just am not happy with super 40 I am running in my twins now. Spoolup is fine as is drive pressure, but egts are out of control. The 35/12 I was running before kept things cooler. I don't know why but it just is.
Joe
 
Ive got a k31 under my stock turbo on my 04.5. Great towing setup. It can pump out 45 psi by 2000 rpm. Love it.
 
My first set of twins was stocker over a s400 and it was great.. IT had a manual wastegate that was made by the gentleman that made the kit...:rockwoot:
 
The exhaust housing on the He351 is a 9cm, kinda small, but if you can find the thread BigBlue wrote he shows how it can be ported out much larger. I want to say 27cm, but I don't think it was that big... Have you checked for any boost leaks? I am just under you on horsepower with my HX40 and I think my EGTs are within reason. Though, the 3rd gen turbo's measurements are almost identical to an Hx40. 60mm inducer and all.
 
Im using the stock wastegate on the hy9. Its set up manually like nathans mpi stock/s400 twins.
 
The stock hx35/12 wastegate has a 17mm cross section diameter that vents the back 3 cylinders because it is divided volute.

The stock He351cw from 04.5-07 5.9liter has a 19mm cross section diameter that vents all 6 cylinders because it is open volute.

I remember reading that MPI suggests you open up the stock wastegate hole if you are pushing big HP with their He351 over s400 setup.

When I modded my He351, I was able to open up the wastegate to 27mm without modifying anything else. If you have a welder, you could fab up a larger wastegate puck and probably get 32-35mm wastegate hole.

I personally think that the 27mm modded opening is plenty for a 600hp twins set that does not plan on shooting N02.
 
hey joe, i would mess with the wastegate, seems to me the super 40 may not be driven hard enough. or maybe go the route of a larger primary instead of a smaller secondary. with my 35/40 my egts got toasty, went to a 62./13 and i cant get them over 1125. have you check drive pressure, or stage pressure? just some thoughts, picks lloyds brain he tunes better than i do. josh

i hated my ext gate, it always got clogged at the worst times. course a tial would work better than mine did.
 
jkretzer said:
hey joe, i would mess with the wastegate, seems to me the super 40 may not be driven hard enough. or maybe go the route of a larger primary instead of a smaller secondary. with my 35/40 my egts got toasty, went to a 62./13 and i cant get them over 1125. have you check drive pressure, or stage pressure? just some thoughts, picks lloyds brain he tunes better than i do. josh

i hated my ext gate, it always got clogged at the worst times. course a tial would work better than mine did.
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I checked for boost leaks found none. Drive pressure is one to one, and half total boost comes from the primary. I have a s400 with a 75 mm comp wheel 1.32 a/r turbine housing I might have to try throwing it on. Spool up is fine and I am seeing right aroung 60 psi of boost. I had trouble with this super 40 as a single never did like it maybe I just got a bum charger. Llyod and I talked about it but he is using my truck now so maybe he can give me some ideas after he drives it around awhile. I need to do something cause towing just aint fun with this setup. the 35/12 kept things cooler towing. I must be doing something wrong.
Joe
 
On the same note, I would like to compare the He351 and the Htbg, or Super B as far as a secondary. Correct me if I am that far off but I would guess all of them as singles can support somewhere in the 425-450ish range with moderate temps. but yet are very different as far as the He351 being a 60/60/9cm and the others being a 57-58 /65/14cm.
What I would like to know is what would one notice from changing from one to another in a secondary application? Let's go ahead and consider that we were going to run a ext. gate with the He351.

Joe, I would expect the 40 to run hotter than the 35 everywhere but 3/4 to full thottle. I noticed that the 35 ran cooler on my setup almost all the time with the only exception being when I was really in the fuel.

Good thread :pop:
 
JFlagg said:
The exhaust housing on the He351 is a 9cm, kinda small, but if you can find the thread BigBlue wrote he shows how it can be ported out much larger. I want to say 27cm, but I don't think it was that big...
Click to expand...

I would really like this read more on this.. I cant find anything.. Help anyone?
 
Mountaineer said:
On the same note, I would like to compare the He351 and the Htbg, or Super B as far as a secondary. Correct me if I am that far off but I would guess all of them as singles can support somewhere in the 425-450ish range with moderate temps. but yet are very different as far as the He351 being a 60/60/9cm and the others being a 57-58 /65/14cm.
What I would like to know is what would one notice from changing from one to another in a secondary application? Let's go ahead and consider that we were going to run a ext. gate with the He351.

Joe, I would expect the 40 to run hotter than the 35 everywhere but 3/4 to full thottle. I noticed that the 35 ran cooler on my setup almost all the time with the only exception being when I was really in the fuel.

Good thread :pop:
Click to expand...

I have to agree with this. When I had a 35/12 and 14 as a top turbo, it always ran cooler cruising or towing temps. The 40 always ran a couple hundred degres hotter cruising. WOT there was no comparison. The 40 was way cooler, well over 200* cooler. IMO the 35 was a better all around setup for me. I'd give the he351 a try. I'm thinking it would be pretty close to 35/40 hybrid at about 1/3 the cost.
 
More on this? Considering putting a set together because I can do it cheap. Does someone have more info on the manual wastegate mod?

600hp max for this set? 3rd gen turbo over S475
 
Anyone do this combo with an external gate? and block off the stock gate?
 
97crewcab said:
Anyone do this combo with an external gate? and block off the stock gate?
Click to expand...

My vote is leave the stock gate and add an external, then add a duel regulator, one for each gate and tune it like that.....hum were did I hear that....Brad Ponci from back in 03'

You guys are thinking and that is all good.

Jim
 
cyric said:
So are you saying it would be worthwhile to swap out my hx40 for an he351?
Click to expand...

Sorry, I was responding to 97's question in your thread...

in your case, however, IMO - yes. The tight 351 will help you get a head start on the EGT curve, and the compressor will do a good job of compounding the K31's boost... just need to mod the Holset's hot side (especially the WG) for max bypass flow and use an external gate (maybe from a thick T3 flange) for sure if fueling heavy, spraying NO2, etc. that will skyrocket drive pressure. Basically, the secondary's turbine/WG combo should efficiently flow everything the primary's compressor can pump out...
 
Jim Fulmer said:
My vote is leave the stock gate and add an external, then add a duel regulator, one for each gate and tune it like that.....hum were did I hear that....Brad Ponci from back in 03'

You guys are thinking and that is all good.

Jim
Click to expand...

That was a while ago. People think its all the new way of setting up turbos. Hell back in 04 i had 3 gates on it. I had 2 on the secondary and 1 on the primary with 3 regulaters. I also ran a hx40 charger grafted into a 14cm housing. (Old news)
 
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