Hopefully will be going FMIC soon and looking for any input on the technical reasons to select an appropriately sized intercooler.

I am looking at 2.5" pipework Probably Stainless as my calculations have indicated an internal velocity of circa Mach 0.27 at circa 400bhp which I have been advised is a good ballpark figure for a compromise of flow restriction and mega lag induced by large volume of pipes.

I am now looking at trying to size an intercooler core. Most seem to opt for a 300mm High x 600mm Long and 75mm thick core. This is pretty much as big as is possible to fit the ST205.

A) Is this big a core required for 400 ish BHP?
B) Is this a sufficient number of rows to keep the pressure drop low enough?
C) Would a core with a greater number of rows that are shorter be more effective at cooling whilst offering a lower pressure drop?
D) Tube & Fin or Bar & Plate design?
E) Lightweight or Heavy (Go for some thermal mass?)

Any comments/ experience welcome and greatly appreciated.

_________________
JP
GT4DC Treasurer

Grey St185 RC
Silver BMW E46 M3
Multicolour yawn Honda VFR400
Silver Honda Civic Type-R

JP, from my meagre knowledge:

A - no problem. Hitch runs a 300 x 600 x 75? and is >500hp
B - I suppose the larger the height and width then the less pressure drop? Mind you I would've thought that the end tank deisgn and internal deisgn of the IC would also play a alrge part in its efficiency?
C - Yes I would've thought so since the air has less distance of "small" bore pipe to travel through, but more of them. I woud've thought that there would be a trade off between distance travelled and the amount of heat given up? i.e. a short pipe from end tank to end tank would not be very good since the air has less chance to give up some heat?
D - as I understand it bar and plate is superior but is a little more costly?
E - I'd worry more about the design...if it weighs more then so be it

I'm also of the opinion that the IC needs to be sized appropriately, and I would be conscious that the engine water radiator also has a job to do and wouldn't want to restrict air flow through this important kit of kit?

_________________
Kris
95 ST205 - slept for 10 years, now waking up...
Avensis
http://www.gtfours.co.uk
_______________________________________
Turbocharging - the replacement for displacement

The standard Evo front mount is supposed to be good for 400hp. Somethings making me think Evo6 onwards but I could be wrong.

Tube and fin is more efficient, bar and plate it a bit old school, but some monster GTR's run them to help prevent the core flexing I believe.

Erm,

Other way round Malc from everything I have read

Bar and plate is more efficient than tube and fin

This is due to the increased area of the flat tubes compared to the rounded tubes

You can picture it if you think about it

Tube/plate ICs use rectangular sections for the air to flow down. This means that you can have cooling fins (or plates as they're called for some reason) that run the entire front to back depth

Tube and fin on the other hand uses a bullnose and bulltailed (?? lol) tube for the air to go down. This means that you cannot have cooling fins for the entire depth of the tube. Hence they are less efficient

advantages :- A given sized bar/plate cooler will always outflow and outcool the equivalent tube/fin one

Downsides :- bar and plate is more expensive. It is also more restrictive to airflow across the core (not flow through it if you see what I mean)
So a gurtmongous bar and plate core whaped in front of the main water radiator will have a bigger water cooling impact than the same sized tube/fin one

Basically, if you want smaller go bar/plate
If you want cheap go bar plate