Boost issue from manifold?

shiftycapone

shiftycapone

wandering the desert
Joined
Oct 26, 2007
Messages
2,034
So I built a log style manifold awhile back from some 1 1/2" sch. 40 pipe, with a wastegate adapter right behind the divider. T4 flange, divided, ported to match. The build of it is in the custom fab section. Now the problems....

Exhaust leaks? NO.
Low boost? YES.
So originally the truck had twins with this manifold (hx52 over ht4c, 67mm over 84) and a 50mm synapse gate into the hotpipe. Spooled alright, and still pulled well on the top, but power felt lower when compared to the older 62/4c setup with untouched mach 6's, as opposed to these bad boys from Weston. So I tightened the gate up as much as possible. Same results, about 50-55psi overall with about 35+ from the primary, WTF? Fast forward..

The mount for the primary, which is also the oil drain, begins leaking. No big deal, I remove the 4c and decide to run the 52 as a single, to see if I can track down the problem. Turbo makes about 35 at wot. Once again WTF? With less fuel I was driving a 471 to around 60psi. I get my hands on a much stiffer preload spring from synapse and throw that bad boy in there, hoping for results. No dice. Turbo makes 40psi at wot. Decide to block off wastegate and go balls out. Once again, 40psi.

I have tried everything. Change timing, dv's, wastegate ( 50mm down to the 39mm seat), no wastegate, tubo blanket, plate adjustment. Same thing always, not the boost it should make. I begin to question if the manifold is just flowing too much. But how? Many people have ran Bodies manifolds, or made their own with good results. I call Weston looking for a little help, and he settles upon the same conclusion. The only thing I have not tried is another manifold. So I put on a pdi t4 that I had around, and am waiting on a spacer to finish the install. We shall see how it goes.

If you have some insight or an opinion, let it out. I'm curious if I'm the only person who has had this problem. And as for fuel, which I do not see is the problem, the truck has the following: Dragonfly pump, #6 or no plate, Westons big 131's ( also tried 181's), 7x13's with .015 off the pintle and .015 of extra stroke, 4k's, and a raptor 150 feeding 50psi. Afc is tuned.
 
shiftycapone said:
So I built a log style manifold awhile back from some 1 1/2" sch. 40 pipe, with a wastegate adapter right behind the divider. T4 flange, divided, ported to match. The build of it is in the custom fab section. Now the problems....

Exhaust leaks? NO.
Low boost? YES.
So originally the truck had twins with this manifold (hx52 over ht4c, 67mm over 84) and a 50mm synapse gate into the hotpipe. Spooled alright, and still pulled well on the top, but power felt lower when compared to the older 62/4c setup with untouched mach 6's, as opposed to these bad boys from Weston. So I tightened the gate up as much as possible. Same results, about 50-55psi overall with about 35+ from the primary, WTF? Fast forward..

The mount for the primary, which is also the oil drain, begins leaking. No big deal, I remove the 4c and decide to run the 52 as a single, to see if I can track down the problem. Turbo makes about 35 at wot. Once again WTF? With less fuel I was driving a 471 to around 60psi. I get my hands on a much stiffer preload spring from synapse and throw that bad boy in there, hoping for results. No dice. Turbo makes 40psi at wot. Decide to block off wastegate and go balls out. Once again, 40psi.

I have tried everything. Change timing, dv's, wastegate ( 50mm down to the 39mm seat), no wastegate, tubo blanket, plate adjustment. Same thing always, not the boost it should make. I begin to question if the manifold is just flowing too much. But how? Many people have ran Bodies manifolds, or made their own with good results. I call Weston looking for a little help, and he settles upon the same conclusion. The only thing I have not tried is another manifold. So I put on a pdi t4 that I had around, and am waiting on a spacer to finish the install. We shall see how it goes.

If you have some insight or an opinion, let it out. I'm curious if I'm the only person who has had this problem. And as for fuel, which I do not see is the problem, the truck has the following: Dragonfly pump, #6 or no plate, Westons big 131's ( also tried 181's), 7x13's with .015 off the pintle and .015 of extra stroke, 4k's, and a raptor 150 feeding 50psi. Afc is tuned.
Click to expand...



Less boost is normal with a manifold, how is the power?
 
DIESEL_POWER said:
Less boost is normal with a manifold, how is the power?
Click to expand...

Good ish, but feels lower than it should. Its very smooth, which is unusual in my experience with big singles. It does hit, but not quite like the other singles I have ran. The 471 hit like a hammer. It may be due to differences in the turbine and the compressor, as it is Borg to Holset. I just think I should make more than 40lbs.
 
Mitch I don't think it's the manifold. The only thing i've experienced was faster getting up to 10psi boost when going from Bodie's piece back to a PDI t4 and slightly slower response above that. I can't say for sure but that's my opinion.
 
Mitch, Weston and I were talking about this the other day. I agreed with Weston as the manifold being the culprit. The Pro-71 on my truck when equipped with the VP with stock injectors and just a box will snap and hit 45 lbs easily. I'm running PDI's manifold.
 
Mr. Farmer, I don't see a boost leak as the problem. It could be, but then why did the 471 spool well and make such good psi? With smaller injectors and a t3 ats manifold as well. I will do a leak test to confirm.

Nick, bodies manifold is roughly the same size as mine, so I don't know why his didn't cause this problem.

The Natural31, I think weston has told me about your setup. This charger was bought new, and has hardly any miles. Everything feels good on it, and so I am stuck as to why it will not make over 40. I have changed most everything to try and narrow it down EXCEPT the manifold. I did not think it would flow so much as to limit boost, but it was my first time. 5k+ rpm and I bet it would kick ass.

The pdi manifold is on, I'm just waiting on a spacer so I can mount the charger. The manifold is flipped, so that I wont have to re-fab the downpipe and IC pipe. And if everything works out I can get the 4c back under the 52.
 
is this the manifold you had a thread on a while back? or am I thinking about someone else?
 
NickTF said:
Mitch I don't think it's the manifold. The only thing i've experienced was faster getting up to 10psi boost when going from Bodie's piece back to a PDI t4 and slightly slower response above that. I can't say for sure but that's my opinion.
Click to expand...

Nick,
the PDI manifold on Mitch's truck now is your old one. I traded him and he fixed the crack. Hopefully it solves the problem.

Mitch what was your time and speed with the 52 vs the 71? I can remember the 71 time and speed but I cant remember the last time we went to the track what you ran.
 
DieselBulldog10 said:
Nick,
the PDI manifold on Mitch's truck now is your old one. I traded him and he fixed the crack. Hopefully it solves the problem.

Mitch what was your time and speed with the 52 vs the 71? I can remember the 71 time and speed but I cant remember the last time we went to the track what you ran.
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A fockin slow 12.4, didn't even break 100mph:hehe: Gate opening early didn't help, gotta love 35psi.

With the 71 first run, 2.5(?) 60ft 12.49( I think)@116mph. I know the mph is right. Second and last run sprayed the .075 jet and cut a 1.67 60ft, 7.7@98mph 1/8th, and 11.8@119mph 1/4. With the mach 6's and lazer cut 181's that came in the pump. 20* timing.
 
O ya now I remember. I was wondering if you had the MPH to keep up with the previous run even though your et was slower. but I see that it wasn't close. I might stop by this weekend if I have the turbos to me by then. I'll call ya.
 
I know its not a fair comparison, but how the hell does Keating get his single tube big ass manifolds to work? Like the one on his rail?? I know that thing turns some good rpm, but come on!!
 
What size exhaust housing do you have? I have some good injectors if you want to try them
 
How would a manifold 'flow too much' and limit the turbo from boosting? No matter the the manifold, ultimately your turbine is gonna be the restriction, right?
 
DIESEL_POWER said:
Less boost is normal with a manifold, how is the power?
Click to expand...

This is 100% correct. Boost is nothing more than resistance to flow. You can make good power with a less restrictive manifold, but the turbos need to be matched to it. If you need better response, a different turbo or turbine housing is needed.
 
shiftycapone said:
Nick, bodies manifold is roughly the same size as mine, so I don't know why his didn't cause this problem.
Click to expand...

hard to say. It must be noted I was running a t66 from turbonetics during going between manifolds which apparantly sucks at higher pressure ratios. It is possible that there was no more boost to be had from this charger via the manifold swap regardless. I doubt it though. Good luck! I take it you don't have the other injectors to swap back in and try any longer?
 
mhuggler said:
This is 100% correct. Boost is nothing more than resistance to flow. You can make good power with a less restrictive manifold, but the turbos need to be matched to it. If you need better response, a different turbo or turbine housing is needed.
Click to expand...
Response is not the problem man, overall boost is.

NickTF said:
hard to say. It must be noted I was running a t66 from turbonetics during going between manifolds which apparantly sucks at higher pressure ratios. It is possible that there was no more boost to be had from this charger via the manifold swap regardless. I doubt it though. Good luck! I take it you don't have the other injectors to swap back in and try any longer?
Click to expand...

No sir they are gone to another home.
 
Tate said:
How would a manifold 'flow too much' and limit the turbo from boosting? No matter the the manifold, ultimately your turbine is gonna be the restriction, right?
Click to expand...

I thought the same thing. Increase flow and pressure drops, but your still going to run into the turbine wheel with sufficient "force". I have thought about heat loss through the manifold as well, but it's hard to test. The manifold is wrapped as best as possible though.
 
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