Intercooler core size - 45-65mm vs 75mm and more

[raziel]

hi guys

I found this intercooler http://cgi.ebay.co.uk/FORD-SIERRA-ES...item19c37cf5d5 and wondering whether it could improve response if mounted in front of the radiator (or behind it? heh) -> in order to have the shortest pipework possible (also - it has 45mm core - it shuld improve the overall response along with short pipework - aint I right? (im not after 600bhp - but healthy 300bhp max

thanks in advance

peter

[Tosseef Hussain]

I have the same size intercooler on my stage 3 CA. Does it's job and isn't too big for the T28 to fill up.

[raziel]

cool
Any tip which model / where shuld I get one?? (I need somethin what is not wider than 70 cm (to be able to fit it in front of the radiator - all of those on ebeay ar either 80cm wide or have the inlet and outlet on the sides (I need somethin that has them facing the engine...

any ideass??

thank yoou

[Tosseef Hussain]

Volvo or Saab ones then. Breakers, 10 quid.....ish.

[croustibat]

hi guys

I found this intercooler http://cgi.ebay.co.uk/FORD-SIERRA-ES...item19c37cf5d5 and wondering whether it could improve response if mounted in front of the radiator (or behind it? heh) -> in order to have the shortest pipework possible (also - it has 45mm core - it shuld improve the overall response along with short pipework - aint I right? (im not after 600bhp - but healthy 300bhp max

thanks in advance

peter

Many people says it *should*. People who have done it and not compared says it does.

This is called pride.

People who have really compared says it does not change anything, or the gain is too small to be measured.

If you want a real increase in spool time, port your head and intake manifold. It will spool 300 to 500rpm sooner, guaranteed.

Another little increase in response is also given by using a ball bearing turbo... If you want a healthy 300HP, you will need a T28 at the very least, so get a roller bearing one. It is called GT2560R now. you could also get a GT2871 (the smaller one), it will spool a little later but should give you room for up to 400HP and more.

Dont mount it behind the radiator anyway, or it will have little flow and hot air. You want to cool the air in the cooler, not heat it. The coolant radiator is used to get coolant to 80°C, but you want your air to be the coolest possible.


Finally, dont forget about the piping... at first i did not want an XSpower/ ebay jobbie, so bought a renault megane intercooler. Piping was a nightmare to do and would have cost a lot. I ended up buying an XS power one, that works perfectly . I get 0.3bar boost at 2000rpm, and IAT is not much above ambiant temp.
I could get boost sooner if i did not use e85 fuel, but considering its benefits ( cost is half the cost of sp98 here, it has 104 octane and reduces exhaust temps), ithink it is a really low price to pay. I wont use sp98 anymore, unless i am forced to

[alanjuggler]

the biggest problem with those RS500 ICs imo, is the way the end tanks are formed mean it will cancel out much of the gains from being a small volume - it'll cause a fair amount of turbulence and probably won't flow fantastically well.

that's why although the XSP/ebay items are generic and a bit larger than ideal because they're side entrance where the pipework usually does a more gentle bend, the flow is improved.

[raziel]

I simply dont belive that the shorter pipework and a bit thinner IC wont improve the response ,...
anyway, doesnt anybody know if this one http://cgi.ebay.co.uk/MITSUBISHI-EVO...item1c185ee69b would fit in front of the rad -> if the battery would be removed to the trunk..?

[IKRAM]

Try your luck with this.
http://cgi.ebay.co.uk/NISSAN-200SX-S...#ht_696wt_1135

Only a day left and its the proper one for an S13.

[alanjuggler]

I simply dont belive that the shorter pipework and a bit thinner IC wont improve the response ,...
anyway, doesnt anybody know if this one http://cgi.ebay.co.uk/MITSUBISHI-EVO...item1c185ee69b would fit in front of the rad -> if the battery would be removed to the trunk..?

people have fit the stock EVO IC on the S13 but it's not a popular choice.

you need to do the maths though.

evo IC on ebay : 500mm x 315mm x 90mm = 14175cm^3 volume.

generic, usual S13 IC : 600mm x 300mm x 76mm = 13680cm^2 volume.

so larger volume because of the greater depth - have to remember that greater depth results in less cooling on the rear fins, so isn't as effective.

the evo one also has 2.5" inlets, the generic one has 3".

shorter pipework may result in lower lag but the problem with a lot of ICs is the flow. that RS500 one with the crappy inlets will cancel out any gains from the short pipe run you could use.

you might see why most people just go for the generic S13 kits. it's a good balance of price and performance.

if you're really interested in trying something different that might actually be more efficient, have a look at the OEM skyline GTR coolers - they have decent formed end tanks that should encourage decent flow across the entire cooler.

http://www.skylineowners.com/forum/s...rcooler&page=2

see top post with dimensions, means it's more like 10440cm^3

(side note, I'm aware that the volume calculation isn't massively accurate for comparison between intercoolers given differing construction - it's meant as a guide.)

[raziel]

oh ok got ur point

and what about this setup (bumblebee's car)
i think it would be possible to fit it infront of the radiator?? - short pipework - nice inlets - good volume I guess... ??

[skyshack]

oh ok got ur point

and what about this setup (bumblebee's car)
i think it would be possible to fit it infront of the radiator?? - short pipework - nice inlets - good volume I guess... ??

It is in front of the rad.
Well the top of the rad. A "V" mount the rad is leant back at an angle and the IC fits in the gap, like top of a 7 with rad as the leg (should be called a "7" not a "V"). Needs a bonnet vent for the IC with ducting. Needs sides sheeting in so air coming though slam panel goes though both and doesn't just exit out the huge gap.

Robs rad of airflow. Rad needs electric fan as the angle means it would be carved up by viscous.

[raziel]

It is in front of the rad.
Well the top of the rad. A "V" mount the rad is leant back at an angle and the IC fits in the gap, like top of a 7 with rad as the leg (should be called a "7" not a "V"). Needs a bonnet vent for the IC with ducting. Needs sides sheeting in so air coming though slam panel goes though both and doesn't just exit out the huge gap.

Robs rad of airflow. Rad needs electric fan as the angle means it would be carved up by viscous.

yeah skyshack you are absolutely right - though I was aware it is a V-mount - its taken from my own topic about V-mount long time ago.. but I wanted to know if that IC could be mounted like SAAB ones - in front of the radiator...?

thanks

[alanjuggler]

you could - have a look for the parts shop max ones that sit in between the lights.

http://www.gtfactory.jp/cms/page.php?11 - about half way down the page.

again, the end tanks aren't ideal but better than the RS500 ones as they're angled slightly.

the other option is to look at the PACE / Forge offerings and see if anything suits. you'll pay the price though - forge stuff is upwards of £400 just for the cooler.

edit, the other option if you're pursuing response is to stay with smaller pipework - 60mm, for instance, instead of moving up to 3"/76mm.

really basically - v = pi * r^2 * h for a metre of pipework.

for 60mm piping.

v = pi * 9 * 100 = 2827.42cm^3

for 76mm piping.

v = pi * 14.44 * 100 = 4536.45cm^3


again, very basic, assuming a metre of pipework. not taking into account pipe bends etc but you can see that it's an appreciable difference. the problem with that is it might limit your ultimate flow (though I think that's unlikely if you're staying with a ~T28 size turbo)

[raziel]

-.....
edit, the other option if you're pursuing response is to stay with smaller pipework - 60mm, for instance, instead of moving up to 3"/76mm.

really basically - v = pi * r^2 * h for a metre of pipework.

for 60mm piping.

v = pi * 9 * 100 = 2827.42cm^3

for 76mm piping.

v = pi * 14.44 * 100 = 4536.45cm^3


again, very basic, assuming a metre of pipework. not taking into account pipe bends etc but you can see that it's an appreciable difference. the problem with that is it might limit your ultimate flow (though I think that's unlikely if you're staying with a ~T28 size turbo)

thanks for your response buddy, it becomes very technical - I appriciate that

have another question if you dont mind - what do you think about this one :

http://cgi.ebay.co.uk/LARGE-Universa...item1c1c3c2b45

I think (on the basis of your advice above) this intercooler could be the best option for me? 5.7cm inlets -> I would have 90degrees silicone bends on them (thus no decreased flow like with the other ones we were talkin about) , plus I measured the engine bay and it shuld be no problem to fit it in front of the radiator if I remove the battery to the boot...

also the core is 65mm thick - not 76mm like most of the intercoolers and yet - it has height of 23 cm which is again a lot less than the ones from kits..

so what do you think??

thank you

Peter

[alanjuggler]

it looks OK - but the ebay ad doesn't give you the core size, just overall, so difficult to make like for like comparison.

to estimate the core width, it's 69cm overall, so knock off 10(ish)cm per side = 7325cm^3.

I'd take that with a pinch of salt, given the estimation/guesswork involved, but looks to be a good size for what you're thinking of (at least, I think so, anyway )

there's loads of stuff to improve the flow between the turbo and the combustion chamber, just take each bit at a time, like croustibat says, there's the inlet plenum / manifold to port match, the head itself to do some work on (I'd just clean up the runners, mostly).

you can get very easily bogged down in the theory, fluid dynamics is complicated and many magnitudes more complicated than what we're talking about here

[croustibat]

Considering lag,volume of air and all, and why an ebay jobbie does not make a real difference, check this.

Your engine with throttle fully opened and no boost has a VE of around 90%. Meaning if you fully open the throttle at idle, it is already sucking in 13.5L per second (1.8L /2 as it is a 4 stroke engine *1000/60 then multiplied by 0.9)

Now, the turbo starts to spool, and helps. You hit around 2000 rpm, go positive boost, around 0.4bar on a T28. You turbo is now feeding your engine something like 37liter of air per second.

Now, you can see that shortening a couple of feet wont change a lot of things.

Another thing to consider, if you want the ultimate intercooler, is the flow inside. Basically, the best form factor is a half circle, with both intake and exit tanks next to each other, connected to the core on the same plan.

It really is a complicated thing. I too like theories, but i like results more. Fact is, head porting gives a real upgrade. It gives better throttle response, smoother power delivery, and faster spool. It increases volumetric efficiency, so you get more torque everywhere.

Better designed intercooled and piping do work too, but it needs a lot more work and expenses. I mean, if you end up using a gt3076r and feed your engine with 2.5bar of boost, you may feel the difference. If you are just using a T28, dont bother.

[alanjuggler]

Considering lag,volume of air and all, and why an ebay jobbie does not make a real difference, check this.

Your engine with throttle fully opened and no boost has a VE of around 90%. Meaning if you fully open the throttle at idle, it is already sucking in 13.5L per second (1.8L /2 as it is a 4 stroke engine *1000/60 then multiplied by 0.9)

I'm not an expert but thinking about your maths logically, if the engine is consuming 13.5 litres of air a second at idle and most people generally have the engine at stoich or richer at idle, that means it's using a little under a litre of fuel a second as soon as you go WOT from idle (which would be silly and theoretically, not possible with most injectors? since it's 370cc/min on standards.)

Most sources seem to suggest that VE at idle and at that sort of range is more like 10-15% (certainly at idle it's 15%, there's others that quote at 1000rpm something like 70% assuming no throttle plate.)

the more I'm reading about this, the more I'm getting confused.

anyway, just about the intercooler it's a worthwhile thing to do - it might not be the top of most people's lists but doesn't mean it's not significant.

[croustibat]

at idle with throttle nearly closed it does not consume 13.5L of air, but i said it was with throttle fully opened, basically i wanted to describe the moment when you start to accelerate @ WOT from idle .

Also, dont compare volume and weight, stoeich is about mass, not volume (1g of fuel for 14.7g of air ) .

The formula is surely a lot more complex, but this should be a nice approximation.

[tomo1]

it's a mass ratio not volume- 1m^3 = 1.225kg for air, 1m^3 fuel = 800kg ish

*EDIT*
a bit slow there.

I work it out at about 1cm^3 per min of fuel for 13.5L of air...

[alanjuggler]

cheers chaps - knew there was something missing. can you tell why I sucked at maths mechanics/physics at college?

tomo - my revised maths now agrees with you