Attention: TDR Forum Junkies 
Hoping some "Diesel Tuners" see this.
Last year, I replaced the stock turbo on my '07, 5.9 with a Garrett stage one with the billet compressor wheel. Tom at Turbo resource set it up for me. At the same time, I also changed the exhaust manifold with a two piece DDP exhaust manifold. The DDP has larger inside diameter porting in the manifold than stock.
My truck is a 2007, 5.9, G56. I run a Smarty JR at the 70 hp setting and the engine is stock. The very best boost I can get is 30 psi at close to 2900-3000 rpm in fifth W.O.T. and I feel that I should have better boost at lower RPM. Tom has been a help in his and continues to tell me that I should be getting closer to 38 psi.
I pressure tested my intercooler and no leaks. I see no apparent leakage at the intake cover on the head but I am not sure what kind of gasket or sealer Cummins used to seal it.
I have wondered about putting back the STOCK exhaust manifold as the I.D. of the manifold is smaller than the DDP manifold and in my thinking, the smaller manifold would increase the exhaust gas velocity and help to drive the hot side of the turbo faster at lower and higher speeds. Many turbocharged diesels I see, light duty as well as heavy duty seem to not have real large exhaust manifolds on them.
I have the O.E. Cummins gaskets to change the manifold but wanted to ask some of you guys first. Otherwise, I am considering having Tom rebuild my stock turbo and going back with it.
Last year, I replaced the stock turbo on my '07, 5.9 with a Garrett stage one with the billet compressor wheel. Tom at Turbo resource set it up for me. At the same time, I also changed the exhaust manifold with a two piece DDP exhaust manifold. The DDP has larger inside diameter porting in the manifold than stock.
My truck is a 2007, 5.9, G56. I run a Smarty JR at the 70 hp setting and the engine is stock. The very best boost I can get is 30 psi at close to 2900-3000 rpm in fifth W.O.T. and I feel that I should have better boost at lower RPM. Tom has been a help in his and continues to tell me that I should be getting closer to 38 psi.
I pressure tested my intercooler and no leaks. I see no apparent leakage at the intake cover on the head but I am not sure what kind of gasket or sealer Cummins used to seal it.
I have wondered about putting back the STOCK exhaust manifold as the I.D. of the manifold is smaller than the DDP manifold and in my thinking, the smaller manifold would increase the exhaust gas velocity and help to drive the hot side of the turbo faster at lower and higher speeds. Many turbocharged diesels I see, light duty as well as heavy duty seem to not have real large exhaust manifolds on them.
I have the O.E. Cummins gaskets to change the manifold but wanted to ask some of you guys first. Otherwise, I am considering having Tom rebuild my stock turbo and going back with it.
