Intercooler pipe size

[calcal]

Hey guys,
Putting a top mount cooler on and just wondering what size pipe I should use.
It's a ZD30 engine.
Cheers

 

[BP90]

From what ive read in almost all the intercooler threads on here. Theres no real point going any bigger then 2.5 which is roughly the size of the intake manifold pipe, as even if you go bigger its going to still go down to 2.5 at the intake manifold.

 

[Lawry]

2.5inch is what im running,
other blokes are running 2 or 2.25 or a mixture of diameter from hot to cold side of the intercooler.

What the perfect size is... very debatable.
The larger the size the great volume/flow capabilities however more lag. and vice versa.

 

[calcal]

2.5inch is what im running,
other blokes are running 2 or 2.25 or a mixture of diameter from hot to cold side of the intercooler.

What the perfect size is... very debatable.
The larger the size the great volume/flow capabilities however more lag. and vice versa.

Any lag with 2.5" pipe??

 

[ahinde85]

If someone has the turbine compressor wheel info and some diameters/etc I don't mind having a crack at the calculations to stimulate this thread ;-)

 

[terra88]

On a top mount the pipe size wouldn't make a huge difference on turbo lag but on front mounts I usually keep the turbo size (pre cooler) the same size as the turbo outlet and then run bigger to the intake. Maybe 2.25 or 2.5".

 

[Lawry]

Being a diesel/ constant air flow. The lag is a hell of alot lower than a throttle body petrol.
And yes mine is a front mount so instead of a 25cm pipe from turbo to manifold. Mind is around 3+metres. so logically is should have some lag. I never tested it before with the boost gauge as it wasn't fitted then. But to be honest it hardly has any lag like...1 second, and that's to reach 17-18psi.

If i was to do it again i wouldn't change it. Just make sure you run the shortest possible route. and have a good exhaust to back it up. Allows to spool quickly.
say 2.5-3 inch mine is 2.5 (one tiny hotdog muffler).

Ive been meaning to be some pics up of my set up. Its in my mind the shortest way to run pipes and doesn't require to much modification.

 

[calcal]

Being a diesel/ constant air flow. The lag is a hell of alot lower than a throttle body petrol.
And yes mine is a front mount so instead of a 25cm pipe from turbo to manifold. Mind is around 3+metres. so logically is should have some lag. I never tested it before with the boost gauge as it wasn't fitted then. But to be honest it hardly has any lag like...1 second, and that's to reach 17-18psi.

If i was to do it again i would change it. Just make sure you run the shortest possible route. and have a good exhaust to back it up. Allows to spool quickly.
say 2.5-3 inch mine is 2.5 (one tiny hotdog muffler).

Ive been meaning to be some pics up of my set up. Its in my mind the shortest way to run pipes and doesn't require to much modification.

Cheers thanks for that lawry.
I've decided to go with 2.5" piping. Also, instead of using elbow silicone bends like others, I'll be using sweeping bends so air can flow better. Also, I'm mounting a fan underneath the cooler to suck air down.

I have a 2.5" straight through exhaust at the moment but will shortly be upgrading to 3".

 

[Lawry]

no worries, im guessing your running a top mount???
Good idea with the bends. I did use silicone but only small straight joining pieces and one 45 short elbow. The rest is a mix of alloy pipe and custom welded exhaust pipe. Your end up with a smooth system.

As as for your top mount you wont get any lag in my opinion.
Some people also report a drop in boost.... as in they loose 1-2 pound from the system due to the resistance of flow. "air flowing past metal" friction.
However this didn't happen to me. get a boost gauge and install it before/ then you will have a good guide to see if there are any changes. You should also be able to report changes in lag from factory.

If you decide on going front mount. I can get some pics for you if you need.

Cheers Matt

 

[calcal]

Yeah mate it's a top mount.

Already got a boost gauge so can measure the difference one cooler is fitted.....then wind the boost back up again haha

 

[Craig09]

Lawry you reckon you could put some pics up of yours??im trying to decide what way to go with mine.going to try to protect this new engine as much as possible so intercooler is first on the list.

 

[Craig09]

ohh and do you have a winch?

 

[Dallas royal]

no worries, im guessing your running a top mount???
Good idea with the bends. I did use silicone but only small straight joining pieces and one 45 short elbow. The rest is a mix of alloy pipe and custom welded exhaust pipe. Your end up with a smooth system.

As as for your top mount you wont get any lag in my opinion.
Some people also report a drop in boost.... as in they loose 1-2 pound from the system due to the resistance of flow. "air flowing past metal" friction.
However this didn't happen to me. get a boost gauge and install it before/ then you will have a good guide to see if there are any changes. You should also be able to report changes in lag from factory.

If you decide on going front mount. I can get some pics for you if you need.

Cheers Matt

Hey Matt did you just use a patrol intercooler for yours? I'm keen to run a top mount due to the distance for front mount and having a gu airbox behind the headlight and was keen to see who's done what before.
Cheers Johnny

 

[ben85]

have a look here d22 intercooler

 

[Dallas royal]

have a look here d22 intercooler

Cheers mate