New intercooler for my BAT

[prodrive]

I bought a new 750hp core for my set-up but I need to do the piping now.
The inlet/outlet of the core is 2.75'' so what should be the piping size for the inlet and the outlet size for the best velocity ?
BTW ,I am selling my Evoms kit if anyone interested.

[blmlozz]

2" is reccomended for ko3\ ko4s so 2.5" or matching the 2.75 with your core for you bat should produce the best results. There's some kind of formula for generally caculating piping size based on hp but I can't remember

[prodrive]

Yup.I think it should be at least 2.50'' for the inlet but I am curious about the outlet size ,I can't decide 2.50'' or 2.75'' ..maybe 2.75'' is overkill ?

[A4 TSCHUSS]

I have read that you should match your intercooler piping size to the size of your turbo outlet and on the intake side increase the size .25" so it realistically should be 2" on the hot side since that is the size of the outlet on pretty much any turbo our car would be running. That will keep the velocity up as well. Just my opinion and what I have read. I think 2.75" would be overkill though.

[bassed]

Keep it 2.5" all the way through.

[mike-2ptzero]

Yup.I think it should be at least 2.50'' for the inlet but I am curious about the outlet size ,I can't decide 2.50'' or 2.75'' ..maybe 2.75'' is overkill ?

Best thing to do is match the outlet of the turbo, this will help keep the velocity up to push the air thru the core and you can go .25" larger on the cold side. The 3076r uses a 2" outlet so your best bet would be 2.25" on the hot side and 2.5" on the cold side. This is what ER uses for their Competition kits.

[t1demont1]

so 2.25 on the hot side and 2.5 on cold side is going to produce more power and faster spool than 2.5 all the way through?

[A4 TSCHUSS]

The thing is if you go to big on the piping then you lose velocity that is why it is recommended to match the intercooler piping to the turbo outlet size then they say to go slightly larger (.25") on the intake side of the intercooler to allow the gases to expand and cool faster while still maintaining velocity.

[Wizard-of-OD]

so 2.25 on the hot side and 2.5 on cold side is going to produce more power and faster spool than 2.5 all the way through?

Depends on what his horsepower goal.The whole point of intercooler piping size is to keep the air flowing through the tubes subsonic.
The ID of the T04S compressor housing is 2" and the OD is 2.5".My advice (for the anal people in here) is to get a 2" ID to 2.5" OD reducer and weld it to the compressor housing then go from there.

[1fstavant]

i think im runnin 3 on the hot and 2.5 on the cold with my prec 750 core on a journal bearing i see full boost by 4000

[prodrive]

I think I will go with 2.5'' all the way , I have the precision core too :)

[A4ringedONE8T]

When I did my new FMIC for the 30 series, I went from 2.25" hot side / 2.5" cold side to 2.5" hot side / 3" cold side. While everyone gave me shit for it, it made spool a bit quicker and the FMIC as a whole made a huge difference over the old one.

With 2.75" connections, I would do a 2.5" hot side and 2.75" cold side

Here's mine

[1fstavant]

no pics with out the bumper but i believe the reason for a smaller hot side is to prevent lag...and a larger cold to increase airflow into the chamber....but let me know how you like the 2.5" piping....

the core is amazing at wot and 18lbs im running 26*c iat temps with out meth or a intercooler sprayer on a 85 degree day after driving for a couple hours lol...great core and for the price you cant beat it

[prodrive]

Hey, thanks for the info. How is the fitment of the precision core ? I guess you have the S4 bumper ..BTW nice core A4ringed.. which core is it ?

[bassed]

Custom Precision core and endtanks, w/ 2.5" all the way through. You will have to trim the support with any of the bumpers and trim a bit even with a Rieger RS4, so I'd imagine just as much trimming with an S4 skin on there as well.

[1fstavant]

i mean it takes some trimming but you can leave some rebar behind and im using the stcok front bumper....

[bassed]

i mean it takes some trimming but you can leave some rebar behind and im using the stcok front bumper....

Do you have any with the bump skin off?

[Pete@IE]

We have tried all sorts of different sizes and found that it makes virtually no difference unless the charge piping is WAY mismatched (ie: all 2" piping on a 550whp car).

I would just go 2.5" all the way through. 2.75" is that much more of a pain in the butt to find cheap bends and silicone and everything for, and you won't gain anything.

[A4ringedONE8T]

Hey, thanks for the info. How is the fitment of the precision core ? I guess you have the S4 bumper ..BTW nice core A4ringed.. which core is it ?

Garrett B&P 22 x 11.3 x 2.5 (core only), the biggest that will fit behind a B6 bumper

Started like this

[A4ringedONE8T]

We have tried all sorts of different sizes and found that it makes virtually no difference unless the charge piping is WAY mismatched (ie: all 2" piping on a 550whp car).

I would just go 2.5" all the way through. 2.75" is that much more of a pain in the butt to find cheap bends and silicone and everything for, and you won't gain anything.

Good point, didnt think about that (2.75" stuff)!!

[prodrive]

We have tried all sorts of different sizes and found that it makes virtually no difference unless the charge piping is WAY mismatched (ie: all 2" piping on a 550whp car).

So ,according to your opinion I can stay with 2'' piping and still get more than 500whp with my precision core ?
1fastavat ; core looks good man

[A4ringedONE8T]

So ,according to your opinion I can stay with 2'' piping and still get more than 500whp with my precision core ?
1fastavat ; core looks good man

Pete is saying 2" piping on a 550whp car IS mismatched.

[Don Supreme]

So ,according to your opinion I can stay with 2'' piping and still get more than 500whp with my precision core ?
1fastavat ; core looks good man

2"

[mike-2ptzero]

2" pipe is way too small for a 500whp setup. But 500awhp on a GT30r? Maybe with a GT35r.

[1fstavant]

thanks and no unfortunately i dont...however rearended someone today so i need a new fender and i could get a new bumper got scratched up...so maybe soon and then maybe with an s bumper

[prodrive]

2" pipe is way too small for a 500whp setup. But 500awhp on a GT30r? Maybe with a GT35r.

Haha I know Mike ,I didn't say 500 whp for my Gt30r I bought the 750hp core also for the future plans like gt35r

[Pete@IE]

I meant that 2" piping with 500+ whp IS mismatched. I said that because i've SEEN it done, and i've seen the car gain power when going to 2.5".

That said, we stayed up late as hell one night and switched my buddies hatch from 2.5" to 3", and changed the throttle from a bored out ITR throttle to a 75mm accufab. He was making ~700whp at the time, and it made basically no difference. It was about 10whp, but at those power levels, on two seperate days / two batches of fuel / totally different weather, i'd basically call that a toss up.

Now that they are making ~900whp, i'm fairly confident if you were to stick the old 2.5" piping back on you'd see a some power loss. The other thing is, if you are maxing the the turbo out, that's when you'll really see the loss (or gains). That's because if the turbo is NOT maxed out, your boost controller will simply dial in more shaft speed to make up for the pressure drop and you still get what you wanted to the manifold. Fairly minor loss then- When the turbo is maxed out and you've got a lot of pumping loss in the intercooler / charge piping, that too can be a situation that's really hurting your power.

In other words, pressure drop isn't the end of the world, if you've got a whole bunch more pressure ready to back it up.

Generally, I would only use 2" on cars under 300whp, and I'd start thinking about going from 2.5" to 3" around the 600-650bhp range.

[prodrive]

It's more clear for me know. Thanks Pete