Boost issue from manifold?

I've heard turbos get alot of their drive from heat. Maybe there's a major internal heat reduction with the type of pipe you used. sche 40 1 1/2
 
shiftycapone said:
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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missed that.
 
Hmm. I know a boost leak on mine popped up between turbo swaps and I lost ~20psi. I run one of Keating's manifolds with 2" primaries. The s471 would do 55-60 psi and the K31 would do the same. Have you changed the load presented to the engine? Less load would mean less happy turbine?
 
joefarmer said:
Hmm. I know a boost leak on mine popped up between turbo swaps and I lost ~20psi. I run one of Keating's manifolds with 2" primaries. The s471 would do 55-60 psi and the K31 would do the same. Have you changed the load presented to the engine? Less load would mean less happy turbine?
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Less load as in less weight? Not following completely man. Are those 2" primaries 2" ID? Thats even bigger than my manifold, as mine is on 1 1/2" ID.
 
shiftycapone said:
Response is not the problem man, overall boost is.
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Well, I think we have different definitions of response, but anyway...Could we see a picture of the manifold? Who knows if someone would see an error in design and/or construction that would cause this.
 
mhuggler said:
Well, I think we have different definitions of response, but anyway...Could we see a picture of the manifold? Who knows if someone would see an error in design and/or construction that would cause this.
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Construction is solid.
Design seems logical and straight forward, but take a look.
 
shiftycapone said:
Construction is solid.
Design seems logical and straight forward, but take a look.
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Wow, that manifold looks strong and well made! The only thing that I noticed was that it doesn't have as much of a "pulse manifold" design as a cummins or ats, ect. has. In other words, the ports going from the head to the "log" part of the manifold don't have much of an angle towards the center of the manifold, especially cylinders 2 and 5. This angle gives the manifold more of a venturi effect which scavenges better. I'm not going to dare to do the math, but I wouldn't doubt that the diameter of the pipe itself is too large. This kills the velocity of the exhaust. I don't know how bad this is for your manifold, but it would pretty much ruin the venturi effect made into a pulse style manifold.
 
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shiftycapone said:
Less load as in less weight? Not following completely man. Are those 2" primaries 2" ID? Thats even bigger than my manifold, as mine is on 1 1/2" ID.
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Yep. Less weight or different gears. Yes, mine are 2" ID. It spools fine with the right converter.
 
joefarmer said:
Yep. Less weight or different gears. Yes, mine are 2" ID. It spools fine with the right converter.
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15 gallon fuel cell was installed, thats it. Gears remain the same. My charger spools fine too, just doesnt make much boost:bang I'll keep fighting the good fight though.
 
Did you get the T4 install done yet? I'm curious if the manifold is the problem because I had saved all your pics and bookmarked that thread. I was planning to build one just like it for my new motor for my puller next year. :what:
 
maybe you could put it on the dyno and feel for leakage around the manifold welds and openings? something could have warped while welding?
 
Got Smoke? said:
Did you get the T4 install done yet? I'm curious if the manifold is the problem because I had saved all your pics and bookmarked that thread. I was planning to build one just like it for my new motor for my puller next year. :what:
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The new spacer just came today, so I will be getting it finished tommorrow as long as I don't get rained out.
SLIPPY said:
maybe you could put it on the dyno and feel for leakage around the manifold welds and openings? something could have warped while welding?
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I'll let you cheak for leaks on the dyno under full bost man...:hehe:
No missed spots when welding, and with the nice MLS exhaust gaskets I have no leaks.
 
what were boost numbers before the new manifold?

you mentioned being able to drive a 471 to 60psi. before or after the manifold?
 
Update: Got the spacer in the mail and the turbo mounted. Despite some rain I got to make a quick test run. Boost remains around the 40psi mark. Boost rises a tad quicker though, and feels a bit more repsonsive. I'll have to go out again for another drive to confirm, hopefully during the day. That being said I did find some interesting things as to why boost is low.

I got home and figured I would look around the engine and check for any leaks. Got out the leak testing stuff and filled the compressor to cold side of the intercooler pipe up with about 10psi, and could immediately hear an audible leak. Got the soap bottle and started checking. Minor leak around the compressor discharge clamp, tightened it up and no more. BUT, both intercooler boots had pinhole leaks that made some good suds at 10psi, took it up to 40psi and had some pretty decent leaks. You could not see these holes just by looking, but under pressure the soap made them plenty visible. Also had some leakage around the clamps, so I'm replacing those as well.I'm ordering new boots, since these are the stock boots. Guess they just finally began to give up the ghost. How long they have been like this? I don't know, but I am hoping this will solve the issue. Focker Out....
 
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