Engine/Transmission (1994 - 1998) -Aftermarket Ex Manifold, feedback, Question for you guys

[Joseph Donnelly]

Are the gaskets sealed well, at the turbo and at the head? If you took off the compressor discharge elbow, did yo check and re-install the orange O-ring? In summary, I would not blame the manifold. If you don't like the transition at the head end, they are easy to port a little with a die grinder and carbide bur. Having built a lot of " go fast cars" you should be familiar with the procedure. Actually, the manifold works well as supplied. A new stock manifold will shrink just like the original one did, and if it breaks an ear off the head, or breaks a bolt for #6, you won't be happy.

 

[budnate]

Joe, I triple checked everything, sealed tight as a frogs azz, I am a pretty meticulous mechanic, I couldnt take it anymore stewing on it and bought a brand new stock manifold yesterday out of Florida, I am going to go back with it, these manifolds shrinking are not a issue until the motors get 200k on them or more from what I have read, I doubt if I will get another 100k on it before I croak.



I can get around the porting issue in my mind at this point of the game but mostly I dont care for the way it changed the characteristic's of how the motor pulls with the BD it ran much better with a stock manifold, not to mention a guy shouldn't have to port a $580 manifold sold as ready to install, it wasn't purchased as a race manifold that needed massaging for my application.



I will post pics when I get it off for reference on how they prep a 12v manifold, have a great 4th.





B.

 

[Bob4x4]

Post pics of the manifold ports when you get it back off. Are you sure you got a 12v manifold and not a 24v.

In any performance app I have always at least match ported the manifolds and smoothed the transitions. On my own truck My ATS lost some serious metal before it got installed

My 12 valve loved the 3 piece manifold. a definite gain in performance.

 

[budnate]

it's a 24v manifold they half azz milled for a 12v gasket... ... .....

 

[Hootguy]

but isnt' the 24 V manifold have the turbo mounted much differently than the 12V,,,i have both side by side and they are different for sure,,,looks like the 24V has the turbo higher,,,that being said,,i hear a lot of BD stuff is ****,,,and customer service is not one of their strong suit,,,seems like they are trying to ride their name now,,,which is going to go downhill fast if they keep selling **** like they sold you,,,for that kind of money,,i expect ready to bolt on,,,not something some kid in the back tried to make work ok,,,LOL

 

[trudydog]

been following this thread closely and learning much thanks ALL! My 96 auto 4x4 struggles much the same with an associated rattle in higher gear (much sound like valve rattle). The rattle is coming from the pax side of the engine and I suspect manifold. I don't have trails or visible cracks that I can tell but was considering the BD change out BEFORE I read this string. anyway, ... B do you have the associated rattle I speak about too? I am ALL OEM btw 113k

 

[budnate]

Hi, no rattle for me... I could hear the faint ex note change and went looking and found a few holes with gasket blowby... take 5' of 3/8 fuel line start the truck and stick one end in your ear and take the other end and probe around all flanges and around the turbo gasket they like to leak also. . you will hear it right away when you find the leak.



ran over a few steep passes with the cruise locked at 74 rpms 2k... . at the hardest part of the hills it would hit 1100 and make 30#s of boost and pull the hill at around 70-72 and still had more power if i wanted it... not bad pulling a 21' sled weighing about 3k,truck full of fuel and some stuff in it... ... I will see what it does later on this summer when I drag it back home with the stock manifold.



sure love rolling up hills with the mighty cummins pulling and leave the other guys behind.....



B.

 

[trudydog]

Thanks! Will do... Yeah that rattle . . rattles me for sure..... want to isolate. Vales all check good so on to the manifold.

 

[budnate]

Hey gang a follow up, I bought a new Cummins Ex manifold , thing is sitting by the front door for a long month an no time to get it on, kids ,work, etc keeping me busy... . going to run the BD through the winter, anyway I hate when interesting threads get dropped, I will report back later with good pictures and butt dyno numbers, lol.

peace, B.

 

[JMcCoy]

My ATS manifold casting was horrible. I had to do so much porting it was ridiculous. After installing it, I noticed the turbo would spool up quicker. I am very happy with it now. There is no way you should be loosing power from installing the BD manifold, assuming the casting is good. I understand the train of thought that the exhaust manifold may be too large so low end power is lost. That would apply to a small block Chevy with large headers. Exhaust scavenging really isn't that importent with a turbo charged engine. I believe something else was left off, damaged, or wrong. I would not put a stock manifold back on. That would just be a step backwards. I would remove the BD and inspect the casting. Just my . 02. Keep us posted.