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Hi guys. I thought I'd post this here as I know I just won't get the level of discussion in the 8P section that I will here
I've been investigating the core size that I'll need to order to effectively cool the charge air on my 2.0 TDI. At present there is an aftermarket FMIC connected (by previous owner) but the stock FMIC was plumbed back in as he reported bad lag in the higher gears. I've not yet had a chance to measure the size of this core but I have been looking at what I will need.
I have found a few interesting articles with mathematical equations to roughly work out the core size:
How to Go Fast Faster: The Math Behind Turbocharging. Part 7: Intercooler Selection | Take me beyond the Horizon
Calculating intercooler size - HomemadeTurbo - DIY Turbo Forum
intercooler size calculator :O) - Evo Owners Forum
The 3rd link was the easiest to understand so I went with the equations there and compared them to core sizes I'd seen on the net/eBay to see what would be best suited.
Ok so here's the math:
-----------------------------------------------------------------------------------------------------------------
3-litres of volume per 100 bhp = 3L
a cross section of 50cm squared per 100bhp .. hight x depth = 50cm2
eg.
as a rough guide
for 300 bhp you would be looking for a 9 L cooler with a cross section of 150cm2 .......... 3 x 3L and 3 x 50 cm2
for 400 bhp you woulds be looking for a 12 L cooler with a cross section of 200cm......... 4 x 3L and 4 x 50cm2
for 300 bhp , if say you where looking to get a cooler with a 2.5" core " 63.5 mm" to get the 150cm2 cross section you would be looking at a cooler with a height of around 24cm h x 6.35cm or 240mm x 63.5 mm = 152.4 cm2 "close enough" .
you will also be looking at a length of 9L devided by 152.4 to get your volume = 9000/152.4= 59 cm giving us a cooler of
240mm h 590mm w 63.5mm d for our 300bhp i would treat this as a minimum size needed
So to finish for my 420 bhp i have chosen a new cooler
300mm h 600mm w 76.2 mm d . 3 inch core
420 bhp x 3L per 100bhp = 420 x 3 = 12.6L needed
cross section of
420 bhp x 50 cm2 per 100bhp = 210 cm2 needed 4.2x50 =
the new cooler works out to have a
228cm2 cross section 300hx76.2w =
13.68L volume = 600w x 228cm2 =
making the new cooler good for around 456 bhp ..
remember this is just the cooler not the pipe work
----------------------------------------------------------------------------------------------------------------
So if I apply the above to my situation I get the following:
220bhp x 3 = 660 (6.6L)
2.2(220bhp) x 50 = 110 cm2
These are the core sizes I've seen online and their stats:
1) 140mm x 550mm x 65mm - 5L - 91cm2
2) 180mm x 560mm x 65mm - 6.5L - 117cm2
3) 230mm x 560mm x 65mm - 8.3L - 149cm2
4) 415mm x 610mm x 57mm - 14.3L - 236cm2
5) 440mm x 610mm x 55mm - 14.7L - 242cm2
So as I need 6.6L - 110cm2 the closest core size is number 2
Obviously none of this takes into account the boost pressure the turbo is producing or the size of pipework so it really is just a rough guide.
Can any of the engineering types out there add any info to this that might help me ensure I don't end up suffering with too much lag or a core that won't be up to the job.
I've been investigating the core size that I'll need to order to effectively cool the charge air on my 2.0 TDI. At present there is an aftermarket FMIC connected (by previous owner) but the stock FMIC was plumbed back in as he reported bad lag in the higher gears. I've not yet had a chance to measure the size of this core but I have been looking at what I will need.
I have found a few interesting articles with mathematical equations to roughly work out the core size:
How to Go Fast Faster: The Math Behind Turbocharging. Part 7: Intercooler Selection | Take me beyond the Horizon
Calculating intercooler size - HomemadeTurbo - DIY Turbo Forum
intercooler size calculator :O) - Evo Owners Forum
The 3rd link was the easiest to understand so I went with the equations there and compared them to core sizes I'd seen on the net/eBay to see what would be best suited.
Ok so here's the math:
-----------------------------------------------------------------------------------------------------------------
3-litres of volume per 100 bhp = 3L
a cross section of 50cm squared per 100bhp .. hight x depth = 50cm2
eg.
as a rough guide
for 300 bhp you would be looking for a 9 L cooler with a cross section of 150cm2 .......... 3 x 3L and 3 x 50 cm2
for 400 bhp you woulds be looking for a 12 L cooler with a cross section of 200cm......... 4 x 3L and 4 x 50cm2
for 300 bhp , if say you where looking to get a cooler with a 2.5" core " 63.5 mm" to get the 150cm2 cross section you would be looking at a cooler with a height of around 24cm h x 6.35cm or 240mm x 63.5 mm = 152.4 cm2 "close enough" .
you will also be looking at a length of 9L devided by 152.4 to get your volume = 9000/152.4= 59 cm giving us a cooler of
240mm h 590mm w 63.5mm d for our 300bhp i would treat this as a minimum size needed
So to finish for my 420 bhp i have chosen a new cooler
300mm h 600mm w 76.2 mm d . 3 inch core
420 bhp x 3L per 100bhp = 420 x 3 = 12.6L needed
cross section of
420 bhp x 50 cm2 per 100bhp = 210 cm2 needed 4.2x50 =
the new cooler works out to have a
228cm2 cross section 300hx76.2w =
13.68L volume = 600w x 228cm2 =
making the new cooler good for around 456 bhp ..
remember this is just the cooler not the pipe work
----------------------------------------------------------------------------------------------------------------
So if I apply the above to my situation I get the following:
220bhp x 3 = 660 (6.6L)
2.2(220bhp) x 50 = 110 cm2
These are the core sizes I've seen online and their stats:
1) 140mm x 550mm x 65mm - 5L - 91cm2
2) 180mm x 560mm x 65mm - 6.5L - 117cm2
3) 230mm x 560mm x 65mm - 8.3L - 149cm2
4) 415mm x 610mm x 57mm - 14.3L - 236cm2
5) 440mm x 610mm x 55mm - 14.7L - 242cm2
So as I need 6.6L - 110cm2 the closest core size is number 2
Obviously none of this takes into account the boost pressure the turbo is producing or the size of pipework so it really is just a rough guide.
Can any of the engineering types out there add any info to this that might help me ensure I don't end up suffering with too much lag or a core that won't be up to the job.