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-   -   RS500 Front Mounts? (https://www.scoobynet.com/general-technical-10/943761-rs500-front-mounts.html)

Kwik 21 July 2012 11:09 AM

RS500 Front Mounts?
 
Hi,
I've been reading on here a lot recently about RS500 intercoolers. Are these genuine items taken from an RS500 or aftermarket parts fitted to some?
Like this? - http://www.ebay.co.uk/itm/COSWORTH-R...item19d3392296
What would be the benefits of having one over say a hybrid front mount?
Where would you then be able to get pipework to fit?
Thanks

**jay** 21 July 2012 11:24 AM

Not genuine as in from an rs500 but the same design.
Jay

Rob Day 21 July 2012 11:30 AM

Maybe ask Banny. He was going down this route.

Rob

jura11 21 July 2012 03:04 PM

Banny and other using Airtec RS500 intercooler core


Jura

prodriverules 21 July 2012 03:06 PM

The only real advantage over a good 'normal' position FMIC is that it shortens the pipe work right down as both inlet/outlet pipes are positioned at the top at slam panel height.
It also looks the bollocks as well mind:D

bustaMOVEs 21 July 2012 03:12 PM

Chat to big arf he has done it

CREWJ 21 July 2012 03:13 PM


Originally Posted by prodriverules (Post 10717253)
The only real advantage over a good 'normal' position FMIC is that it shortens the pipe work right down as both inlet/outlet pipes are positioned at the top at slam panel height.
It also looks the bollocks as well mind:D

How does that help?

Surely the cooling effect of the inter cooler would be diminished by only having the flow at the top?

prodriverules 21 July 2012 03:23 PM


Originally Posted by CREWJ (Post 10717258)
How does that help?

Surely the cooling effect of the inter cooler would be diminished by only having the flow at the top?



The intercooler is massive,it is as effective as any good FMIC but the inlet/outlets of the cooler are positioned at the top/up high so when put into position you can have a short run from turbo-IC and IC-throttle body.
It would over half the length of normal IC pipe work thus reducing lag[marginal though]

harvey 21 July 2012 06:10 PM

Too big or bigger than required to do the job is a bad thing.
The first two questions are what is the construction method? Tube and fin, preferable or bar and plate, not as good for our applications.
Next, measure the pressure drop, not the vendors claims but actual pressure drop in your installation. This can be done with a magnahelix guage or two boost guages with suitable welded or tapped nipples.
In operation, an ACT guage will indicate how well or otherwise the setup is functioning.

Kwik 21 July 2012 09:30 PM


Originally Posted by harvey (Post 10717472)
Too big or bigger than required to do the job is a bad thing.
The first two questions are what is the construction method? Tube and fin, preferable or bar and plate, not as good for our applications.
Next, measure the pressure drop, not the vendors claims but actual pressure drop in your installation. This can be done with a magnahelix guage or two boost guages with suitable welded or tapped nipples.
In operation, an ACT guage will indicate how well or otherwise the setup is functioning.

What are the main factors in deciding what IC to have Harvey? Is it not the case of "bigger is better"???
I'm eventually looking at 2.1, SC42 or 46.

harvey 21 July 2012 09:44 PM


The first two questions are what is the construction method? Tube and fin, preferable or bar and plate, not as good for our applications.
Next, measure the pressure drop, not the vendors claims but actual pressure drop in your installation. This can be done with a magnahelix guage or two boost guages with suitable welded or tapped nipples.
In operation, an ACT guage will indicate how well or otherwise the setup is functioning
.

Now a lot of people put effort in to reducing the pipe run length. It makes a small difference in the overall scheme of things and running far too big a core beyond a certain point just adds to volume and has little or no effect on ACTs if the core is efficient and already sufficiently large to handle the thermal load.

jura11 21 July 2012 10:29 PM

About the ACT,on our one we are seen maximum 38C on the drag strip(Santa pod) after 10-15 drag runs,around 28C when we are normal driving motorway and B-roads,33C on track days



Jura

harvey 22 July 2012 12:21 AM

The FMIC performance is measured in Deg C over ambient.
Obviously the outside air temp varies so you compare performance by the temp difference over the ambient or OAT and the ATC is usually measured just before the throttlebody.

jura11 22 July 2012 12:54 AM


Originally Posted by harvey (Post 10718052)
The FMIC performance is measured in Deg C over ambient.
Obviously the outside air temp varies so you compare performance by the temp difference over the ambient or OAT and the ATC is usually measured just before the throttlebody.

Harvey we have fitted ACT sensor fitted before throttle body

On drag strip outside temps has been around 20-25C,mixed motorway and B-road driving temps has been 25-28C,track days around 20-25C


Jura

Kwik 22 July 2012 06:07 AM

Let me see if I've got this straight...
Tube and Fin is preferable to bar and plate, is there a visible way of knowing which is which?
I'd then fit an ACT gauge before the throttle body to know how much boost can safely be used? Do we then get into the realms of how accurate an ACT is used or is a cheap and nasty one like this ok?
http://www.ebay.co.uk/itm/Air-Charge...item231fb18a3b

Could having a larger core have a negative effect on performance on a moderate build, or would it just be a case of overkill?

CREWJ 22 July 2012 09:54 AM


Originally Posted by prodriverules (Post 10717270)
The intercooler is massive,it is as effective as any good FMIC but the inlet/outlets of the cooler are positioned at the top/up high so when put into position you can have a short run from turbo-IC and IC-throttle body.
It would over half the length of normal IC pipe work thus reducing lag[marginal though]

Yes that's all well and good but you are only utilising the top of the intercooler. Might as well just have one as tall as the pipework and anything below is not cooling anything.

Rheid 22 July 2012 11:00 AM


Originally Posted by CREWJ (Post 10718186)
Yes that's all well and good but you are only utilising the top of the intercooler. Might as well just have one as tall as the pipework and anything below is not cooling anything.

Not true, if the end tanks are well designed there will be flow through the entire core.

eggy790 22 July 2012 02:45 PM

That aside, evryone running the rs500 cooler is runing 600+ bhp, (big arf/hard p1 etc.) so they cant be that bad? Specially since the guys who stuck them on had hybrid intercoolers before, so they must be an improvement?

Kwik 22 July 2012 03:25 PM

That's my point really. I'm aiming for 400/400 in the end, so not exactly needed but if I invest in one now I wouldn't need to change later if I went further. I just need to know if it would have a detrimental effect at all. Oh and where to get pipe work made up lol.

Arch 23 July 2012 02:25 AM


Originally Posted by eggy790 (Post 10718507)
That aside, evryone running the rs500 cooler is runing 600+ bhp, (big arf/hard p1 etc.) so they cant be that bad? Specially since the guys who stuck them on had hybrid intercoolers before, so they must be an improvement?

Thats a bit of an assumption as I would put money on no one having flow tested them. The main reason would have been for the pipework run.

stevep360 23 July 2012 02:59 AM


Originally Posted by eggy790 (Post 10718507)
That aside, evryone running the rs500 cooler is runing 600+ bhp, (big arf/hard p1 etc.) so they cant be that bad? Specially since the guys who stuck them on had hybrid intercoolers before, so they must be an improvement?

Banny said the hybrid was not functioning after 500 or so horsepower, think jef had the same problem.

CREWJ 23 July 2012 07:57 AM

I'm still sceptical until I see any data.

eggy790 23 July 2012 09:28 AM

It was 560 where banny had an issue mate. On WOT the temps were rising with revs. Pretty sure omar on here had the same at 600 on a 2.1 with meth

Kwik 23 July 2012 10:57 AM

Seen as i won't be anywhere near those figures i may just go for a Hybrid then. I'm not sure Banny has had a run or commented on it since the RS500 was fitted.

eggy790 23 July 2012 11:22 AM

he didnt get the rs500 in the end, got the hyperflow front mount instead, saving time and fabrication.. and on WOT temps are actually going down now at well past 600..

harvey 23 July 2012 10:38 PM


Originally Posted by Kwik (Post 10718106)
Let me see if I've got this straight...
Tube and Fin is preferable to bar and plate, is there a visible way of knowing which is which?
I'd then fit an ACT gauge before the throttle body to know how much boost can safely be used? Do we then get into the realms of how accurate an ACT is used or is a cheap and nasty one like this ok?
http://www.ebay.co.uk/itm/Air-Charge...item231fb18a3b

Could having a larger core have a negative effect on performance on a moderate build, or would it just be a case of overkill?

Tube and Fin is preferable to Bar and Plate on a petrol engine where there is a lot of throttle variation and therefore power variation such as you get on a road car but there will be applications where a bar and plate is preferable. For a start it is a heavier lump of aluminium and will absorb more heat over time but it will not react as quickly to varying conditions as will a tube and fin. This is a complex issue.
To try to explain further, on a constant speed diesel generator engine for instance a bar and plate with a good air flow to it would be preferable to a tube and fin. However, a tube and fin by nature of its construction will almost always have a far smaller pressure drop so the turbo has to work that much less to achieve the desired manifold boost pressure.
Bar and plate is exactly what it says as is a tube and fin. Layers of tube separated by thin aluminium wafers to dissipate the heat. Obviously the tube and fin is of lighter construction as it is not solid bar.
Now 400 bhp is not a big power figure and it will not take much of an intercooler (if it is efficient) to control charge air temperatures from the compressor on that particular engine providing the turbo is operating within its efficiency range. Manufacturers only want to manufacture a limited number of core sizes so it is quite normal for cars to be fitted with cores that are bigger than required, particularly at the bottom spectrum of the power range where an FMIC really starts to show benefits eg. 400 bhp.
All the current Hybrid cores are rated at 600 bhp or more with some of the GT2 being rated 700 plus bhp.
As explained above, too big a core could have a negative effect.
Until you have firm information on ACTs and ambient temperatures recorded at a particular time you cannot determine how well an intercooler is working or otherwise.
There are other factors to consider too.
Has the core been painted?
Is the pipework efficient, ie. correct diameters and smooth bends?
Is the cold side of the pipework lagged to keep out latent or radiated heat?
Is the hot side routed away from any heat source in excess of the compressor discharge air temperature which is generally 100-200 deg. C. but more likely around 160 deg. C?
Is the air routing to the core and around the engine efficient?
I cannot comment on the RS500 copy cores referred to as I have not tested or even seen one of these in the flesh but I can tell you that you will be very hard pressed to find a core that will out perform any of the Hybrid GT2 cores in like for like situations and I have specifically conducted tests on Perrin, APS, Hyperflow and others. Some of the cheap intercooler kits are total rubbish, presumably produced for visual effect only.
As already referred to above a big consideration is whether the turbo is operating within its effiiciency envelope and it is possible to observe quite stark differences in intercooler performance when a turbo is changed without any other change to the intercooler or engine.

As an example while rolling road mapping last Friday we struggled to get air charge temperatures more than 10 degrees C. above ambient ie. 34 degrees and 24 degrees. Previously same car but with a different turbo producing less power temperatures were as much as 16 degrees over ambient.

bigarf 24 July 2012 07:06 AM

3 Attachment(s)
i had the aps dr725 on mine before i fitted the rs500 cooler.i didnt take the aps off because it wasnt doing the job as it was a very good intercooler indeed.the reasons for me changing it were that i had spun my inlet manifold in the winter months when i had time to kill.i had seen the rs500 coolers fitted and thought what the hell i'll do it.i had one made by pro-alloy and fitted it myself which takes a bit of fabricating,then you need to do the same with the rad.all in all i dont think there is any major noticable difference from losing all the pipework but there was a couple of kilo in weight loss atleast,and it also cleared a lot of space in the engine bay.i think the end result is that its a hell of a lot of messing about but if you dont by a cheap ebay jobbie it will do the job.
Attachment 68368
Attachment 68369
Attachment 68370

harvey 24 July 2012 10:04 AM

That isn't Arf nice. :)
A fair bit of work there and very tidy.

As regards inverting the core so entry and exit are at the top, on our cores, as with most other kit cores, it involves a fair bit of work and I am undecided as to the wisdom of doing this anyway.
The reduction in pipework length or volume makes no difference that I can measure but it must make a small difference. Inreasing the core size at the same time will negate any benefit you have just created unless the existing core was too small or less efficient than the replacement.
As we all know, heat rises so I suspect hot air in at the bottom and coolled air out on the other side at the bottom is more efficient but I do not know for sure. I have only had two installations to play with to try to find an answer and this also included using an infra red thermometer to look at heat distribution across the core surface. I know that Hybrid spent a lot of time redesigning the intercoolers to improve heat distribution over as wide an area as possible and this is why the end tank design is substantially different as well as other suttle differences to improve flow.
I don't know all the answers but I know a man who will know more so I will ask some questions and get back with his answers.

Infected by sti 24 July 2012 10:31 AM

Nice one Harvey, certainly making an interesting read :thumb:

Intercooler certainly looks neat and tidy sat in there bigarf looks nice under the bonnet too ;)

banny sti 24 July 2012 10:39 AM

2 Attachment(s)
I was running a newage hybrid core with 2.5" pipe work and it was maxed at mid 500s, ACT's as eggy stated were rising with the revs. Decided on a hyperflow purely for less work and also changed the pipework for 3" on the inlet.

Even after repeated runs on the dastek dyno (which run hotter than a Dyno Dyanmics) with more boost the max I have seen is 40 degrees ACT.

Old cooler

http://i258.photobucket.com/albums/h...tercooler1.jpg

Attachment 68371

Old pipework

Attachment 68372

New cooler

http://i258.photobucket.com/albums/h...i/IMG_8319.jpg

New pipework

http://i258.photobucket.com/albums/h...i/IMG_2188.jpg


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