which exhaust manifold to replace on LBZ

[08lmm72mm]

The benefit with Rick @ ProFab is customer support and a much higher quality product. I'm not dogging PPE at all but they aren't the same caliber/quality as Rick's stuff.

I won't disagree with you. Ive read so many threads now dating back the last 10 years I can't find anyone yet other than gmduramax that has said with confidence that up pipes alone has given concrete gains. I most definitely wanted to go with Rick's but I got brand new PPE up pipes with gaskets for $350 CND and free shipping. Rick's up pipes with no gaskets are I believe $400usd + shipping + gaskets + customs and duty.

Will Rick's outflow and outperform the PPE up pipes? Probably. Will it be enough to justify paying double? Maybe if I was racing but it's just for my DD

 

[08lmm72mm]

IMHO on all the PPE and larger style manifolds and up pipes, you gain turbo lag.

This is a concern of mine hence why myself I just want to upgrade the uppipes. I'm hoping to increase the spool time a bit. I got some blankets from Levi coming aswell.

 

[Bdsankey]

IMHO on all the PPE and larger style manifolds and up pipes, you gain turbo lag. you have a larger volume pipe that needs to be filled more and also means the speed will slow untill volume has caught up. been in a few stock head/cam trucks with either stock turbos or 300 frame trubo trucks that proved that. Cams and heads mitigate this but its much like matching a converter with a turbo. manifolds and up pipes should be matched with the heads/cam/turbo/s

I have never done any back-to-back testing on trucks other than a friends LB7 with a 10mm, SAC45%, and a Dan's 64mm supercore. While we didn't look at logs, seat of the pants shows it to be about the same (within error from run to run) and he insists he saw a 200f temp reduction going to the DHD manifolds/up-pipes (same as PPE/DMax Store/Rudys etc).

 

[Chevy1925]

I have never done any back-to-back testing on trucks other than a friends LB7 with a 10mm, SAC45%, and a Dan's 64mm supercore. While we didn't look at logs, seat of the pants shows it to be about the same (within error from run to run) and he insists he saw a 200f temp reduction going to the DHD manifolds/up-pipes (same as PPE/DMax Store/Rudys etc).

doing the lag test that Yellowchevy and i came up with would show additional lag. Dont get me wrong, there are ways to midigate the issue but with alot of guys (not on here) that like to just bolt on and go fast, they wont put that kind of time in to fix the issues.

 

[Bdsankey]

doing the lag test that Yellowchevy and i came up with would show additional lag. Dont get me wrong, there are ways to midigate the issue but with alot of guys (not on here) that like to just bolt on and go fast, they wont put that kind of time in to fix the issues.

I'll have to do that test on the next truck I put them on before and after. Also, that bolded line is extremely accurate in today's market.

 

[N2BRK]

I remember an old thread on this site with a stock max effort LBZ... hang on. Here it is:

 

[08lmm72mm]

I remember an old thread on this site with a stock max effort LBZ... hang on. Here it is:

Well that's depressing haha. If I spent all that money on those mods before the built trans, big turbo, Injectors and pump I'd be heavily discouraged lol.

 

[TheBac]

Im just going to sit over here in Stock-LB7-580hp-Land and agree to disagree concerning larger uppipes and manifolds, stock turbos and spool times vs power......because I like my "job"......

 

[Chevy1925]

Im just going to sit over here in Stock-LB7-580hp-Land and agree to disagree concerning larger uppipes and manifolds, stock turbos and spool times vs power......because I like my "job"......

Oh Tom, you know I don’t give a crap. Let it fly!

 

[KyleC4]

I agree. Let it fly Tom. With all the variables that effect spool, air speed, egt’s, blah blah blah who can be wrong ? These always make for good discussions when people share their experiences.

 

[N2BRK]

I'd love to learn and gather more info on this. A lot of what is out there is from the gas world, and while the theory is the same, the felt/measured impact can be very different for us.

 

[08lmm72mm]

Found some evidence haha

 

[Dozerboy]

I believe Empire diesel has some videos on YouTube of them testing parts like this. That might be the information on N2BRK screen shot.

 

[N2BRK]

The screen shot I put up was from a post on this site a few years back.

 

[N2BRK]

Little Product testing on the Engine Dyno Results

Hey guys we just recently did some engine dyno testing with a bone stock LBZ with 280,000 miles on it. Quick run down of the motor. - New Stock Cp3 - New Stock Injectors All remaining parts of motor 100% stock (Intake, Intercooler, Motor Internals, Cylinder Heads, Turbo, Up-pipes, Manifolds)...

www.duramaxdiesels.com

 

[08lmm72mm]

I would 100% recommend up pipes I picked up 3mph in the 1/4 with the stock turbo and while spraying also, they also help spool

I agree 100% with this statement. My PPE uppipes are on with the drivers side LML manifold and I can say they are a definite improvement. Stock up pipes were choking out my turbo down low. I've gained all kinds of throttle response and when the turbo starts to spool its pretty much instant now and it hits with a violent hammer of torque its awesome

 

[RickDLance]

I asked Rick (Profab) and he said I'd have no gain changing my stock uppipes. And that's with a 68stg2r and 12mm/40-overs Hmm.

Not sure where you got that. In the early dyno tests 25 hp is what the up pipes made on a bone stock LLY.

 

[RickDLance]

ou guys need to understand there is a speed and flow that is the main concern.

Is the stock manifold and uppipes causing higher EGT's due to restricted flow path and increasing drive pressure? or is it the turbo? bad tuning?

there is such thing as too big of exhaust manifold and too small. IMHO, the best setup for a truck on a stock turbo that is going to be pushing it either as a single or as the high pressure turbo in a twin kit is an LML manifold and ricks tow flow up pipes. Why? because you are still going to be limited on flow out of the turbo and you cant be turning rpm's well beyond what the stock turbo can provide for air. Thus velocity out of the head and flow out of the head is limited. BUT when you are trying to get everything you can, the up pipes and driverside maniflold has some restriction.

IMHO on all the PPE and larger style manifolds and up pipes, you gain turbo lag. you have a larger volume pipe that needs to be filled more and also means the speed will slow untill volume has caught up. been in a few stock head/cam trucks with either stock turbos or 300 frame trubo trucks that proved that. Cams and heads mitigate this but its much like matching a converter with a turbo. manifolds and up pipes should be matched with the heads/cam/turbo/s

A lot of good stuff here.

 

[N2BRK]

I went back and re-read the email. I didn't ask about power, I asked about damaging them at 45psi with my current set up. Sorry to misquote you!

On Sep 14, 2021, at 4:36 PM, Rick Lance <[email protected]> wrote:

I don't no what the limits of stock are. I don't think you're there yet though.
On 9/14/2021 3:20 PM, N2BRK wrote:

Oh. I asked you if you knew or had an opinion on the limits of stock. I’m wondering if I should step up, or at 45psi am I still fine with the stock uppipes.

 

[RickDLance]

You can't just rate by PSI, you need to know the egt's too. What egt's are you seeing?