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Obviously if you've landed on website, then you have some interest in cooling products. It can be seen from the content and effort put into website that it is designed not only to promote products but also to educate you, the customer.
The information below is my opinion on intercoolers, based on the experience and sights we see everyday at work, our hundreds of hours on the flow bench, & all the times at a dyno with accurate digital, both probe & infra red, thermometers. We hope this will help you in choosing which type of intercooler is best suited to your performance requirement, pocket, driving style & car.
Before we start, remember that almost every motorized component is a compromise to some extent. Adding an intercooler to your super/turbocharged engine costs power & throttle response whilst in vacuum & very low boost! Fit an intercooIer to a naturally aspirated engine & see what it does to the power output curve. For a couple of decades when nearly all competition & modified street engines in Malaysia were naturally aspirated, opening up the ports or at least matching them with the intake manifold was almost mandatory. So we worried about a small mismatch of usually no more than 0.5mm. then, but some people now buy a great monstrous chunk of alloy that tortures the same intake charge (& isn't cheap) without much thought at all ! An intercooler causes a static pressure drop across the core because of the extra resistance of the Intake charge "rubbing" on the internal walls of the "tube" & cooling "fins/ribs" create. This can vary between approximately 0.3 to 5.0 psi. static pressure drop. The trick is too cool the intake charge the most, with the least static pressure drop. The more temperature that is pulled out of the intake charge, the higher the dynamic pressure drop has to be, because the cooler air is denser & occupies less volume. Simple physics. To judge a core properly on pressure drop, you have to know the static pressure drop & subtract it from the dynamic pressure drop, with the higher resulting figure indicating a more efficient core - the exact opposite to what you may first think. The denser the air, the more oxygen ( there is approx. 22 % oxygen in the atmosphere, & it is only oxygen that will burn in the combustion mixture), the more kw. produced. A rough rule of thumb is for every 10° farenheight - 1% extra kw. is produced ! So even though it does theoretically cost power with pressure drop, the denser intake charge easily compensates for this, with a power gain between not much to a bloody lot, realized !! The more the charging device beats & heats up the intake charge, the higher the power gains from intercooling & more importantly to me, the safer (engine component life) the gains are made. No point in winning the race back to the mechanic for a new headgasket , or worse, a new set of pistons, each time.
The heat from the intake charge is dissipated by contact with the surface of the interior walls (fins or extrusions), and then it transfers through the thickness of the "tube" wall to the surface of the exterior fin, from where it is transported away by the passing ambient air flowing through the core.
It seems that due to the cost of new fabricated intercoolers, a lot of people are looking for a cheap alternative. However, as the old saying goes, 'you only get what you pay for' and usually the same applies to intercoolers. There are significant differences in intercoolers, not only in core construction (bar and plate or tube and fin etc.), but also their design (especially end tank design).
There is usually a reason for the cost involved in buying a new intercooler and they do offer advantages over other options, especially cut down truck intercoolers
Not all Chinese intercoolers are created equal. I can not stress this enough ! They do not come from the same factory. There are at least 8 factories that have contacted us with total different addresses & then there are different named companies within these addresses, which is how some flaunt the copyright laws that western compan - ies must abide by. A couple of factories make very good units, some are okay, & some are downright bad. To complicate purchasing further, some size intercoolers from the same factory are good & other sizes bad. How do I know this, we tested some 75mm units from an importer, which came up good in all aspects & unfortunately for us quite good in a couple of aspects, so they represented excellent value. We have sold a few of these without one complaint. They also imported some 90mm & 100mm intercoolers from the same factory. After getting some returned with vocal complaints because power output & response dropped when these were fitted (often replacing a 75mm unit), they sent one each up to me for testing. Just looking at them showed a close fin pitch. Results are listed below. We are talking all bar-plate construction with these imported intercoolers. The sad part of all this is there is no way of accurately listing who's who, most factories will stamp any name onto there product!
Intercooler - Size Type Flow Rate-corrected Notes.
Chinese 600x300x90mm. Bar-Plate - 3" inlet. 299.3 cfm
Chinese 600x300 x100mm. Bar-Plate - 3" inlet. 330.9 cfm.
RRP-610x302x91mm. Tube-Fin - 3" inlet 471.4 cfm.
RRP-610x302x91mm Tube-Fin - 3" inlet 493.3 cfm. With our optional venturie plate option
A few intercoolers have weeps, or sometimes leaks, out of the box, which makes me think that they will develop more leaks ( maybe even if they don't have any when new) early in their life, with the rigors of hot-cold / press-ure - vacuum cycling of normal use.
Our testing & feedback from some reputable dyno shops suggest that the majority of Chinese 'coolers do a good job up to the point of being worked hard & then gains exponentially taper off. A couple of years ago, they generally had a basic fin design @ a course pitch in a small 'tube', meaning they had a low pressure drop but not good cooling efficiency, so do a good job for an engine with an efficient turbo operating in the low-middle of it's efficiency map. Try & run too much boost & they will 'choke' & pressure drop will soar. The later trend seems to be much closer fin pitch, but still in a small 'tube', restricting flow even more, & worse still 'choke' more at a comparative lower boost. The closer fin pitch which gives better cooling rates, would only increase performance if the tube length was shorter, as the cooling efficiency quickly exponentially decreases (we have placed probes @ 100mm increments along tubes of both air-air & dry ice intercoolers) & the pressure drop (more slowly) exponentially increases along the length of a tube, meaning there is a 'sweet spot' where cooling rate & pressure drop give maximum performance. Sorry guys, but our parchment 'for big is better' philosophy & the fact that the Chinese factories don't seem to have much technical inkling of how an intercooler works, means that allot of purchases will never give near the gains possible & some, well, they're just a waste of your 'cheap money' !!!
They really have there place in the market, are very good for anyone seeking a moderate power gain with a limited budget & for more gains than this, become increasingly more difficult to gauge if they will do the work you need , all this - is of course if you get a good one !
Intercooler Tech/Foto
http://rossracing.fotopages.com
The information below is my opinion on intercoolers, based on the experience and sights we see everyday at work, our hundreds of hours on the flow bench, & all the times at a dyno with accurate digital, both probe & infra red, thermometers. We hope this will help you in choosing which type of intercooler is best suited to your performance requirement, pocket, driving style & car.
Before we start, remember that almost every motorized component is a compromise to some extent. Adding an intercooler to your super/turbocharged engine costs power & throttle response whilst in vacuum & very low boost! Fit an intercooIer to a naturally aspirated engine & see what it does to the power output curve. For a couple of decades when nearly all competition & modified street engines in Malaysia were naturally aspirated, opening up the ports or at least matching them with the intake manifold was almost mandatory. So we worried about a small mismatch of usually no more than 0.5mm. then, but some people now buy a great monstrous chunk of alloy that tortures the same intake charge (& isn't cheap) without much thought at all ! An intercooler causes a static pressure drop across the core because of the extra resistance of the Intake charge "rubbing" on the internal walls of the "tube" & cooling "fins/ribs" create. This can vary between approximately 0.3 to 5.0 psi. static pressure drop. The trick is too cool the intake charge the most, with the least static pressure drop. The more temperature that is pulled out of the intake charge, the higher the dynamic pressure drop has to be, because the cooler air is denser & occupies less volume. Simple physics. To judge a core properly on pressure drop, you have to know the static pressure drop & subtract it from the dynamic pressure drop, with the higher resulting figure indicating a more efficient core - the exact opposite to what you may first think. The denser the air, the more oxygen ( there is approx. 22 % oxygen in the atmosphere, & it is only oxygen that will burn in the combustion mixture), the more kw. produced. A rough rule of thumb is for every 10° farenheight - 1% extra kw. is produced ! So even though it does theoretically cost power with pressure drop, the denser intake charge easily compensates for this, with a power gain between not much to a bloody lot, realized !! The more the charging device beats & heats up the intake charge, the higher the power gains from intercooling & more importantly to me, the safer (engine component life) the gains are made. No point in winning the race back to the mechanic for a new headgasket , or worse, a new set of pistons, each time.
The heat from the intake charge is dissipated by contact with the surface of the interior walls (fins or extrusions), and then it transfers through the thickness of the "tube" wall to the surface of the exterior fin, from where it is transported away by the passing ambient air flowing through the core.
It seems that due to the cost of new fabricated intercoolers, a lot of people are looking for a cheap alternative. However, as the old saying goes, 'you only get what you pay for' and usually the same applies to intercoolers. There are significant differences in intercoolers, not only in core construction (bar and plate or tube and fin etc.), but also their design (especially end tank design).
There is usually a reason for the cost involved in buying a new intercooler and they do offer advantages over other options, especially cut down truck intercoolers
Not all Chinese intercoolers are created equal. I can not stress this enough ! They do not come from the same factory. There are at least 8 factories that have contacted us with total different addresses & then there are different named companies within these addresses, which is how some flaunt the copyright laws that western compan - ies must abide by. A couple of factories make very good units, some are okay, & some are downright bad. To complicate purchasing further, some size intercoolers from the same factory are good & other sizes bad. How do I know this, we tested some 75mm units from an importer, which came up good in all aspects & unfortunately for us quite good in a couple of aspects, so they represented excellent value. We have sold a few of these without one complaint. They also imported some 90mm & 100mm intercoolers from the same factory. After getting some returned with vocal complaints because power output & response dropped when these were fitted (often replacing a 75mm unit), they sent one each up to me for testing. Just looking at them showed a close fin pitch. Results are listed below. We are talking all bar-plate construction with these imported intercoolers. The sad part of all this is there is no way of accurately listing who's who, most factories will stamp any name onto there product!
Intercooler - Size Type Flow Rate-corrected Notes.
Chinese 600x300x90mm. Bar-Plate - 3" inlet. 299.3 cfm
Chinese 600x300 x100mm. Bar-Plate - 3" inlet. 330.9 cfm.
RRP-610x302x91mm. Tube-Fin - 3" inlet 471.4 cfm.
RRP-610x302x91mm Tube-Fin - 3" inlet 493.3 cfm. With our optional venturie plate option
A few intercoolers have weeps, or sometimes leaks, out of the box, which makes me think that they will develop more leaks ( maybe even if they don't have any when new) early in their life, with the rigors of hot-cold / press-ure - vacuum cycling of normal use.
Our testing & feedback from some reputable dyno shops suggest that the majority of Chinese 'coolers do a good job up to the point of being worked hard & then gains exponentially taper off. A couple of years ago, they generally had a basic fin design @ a course pitch in a small 'tube', meaning they had a low pressure drop but not good cooling efficiency, so do a good job for an engine with an efficient turbo operating in the low-middle of it's efficiency map. Try & run too much boost & they will 'choke' & pressure drop will soar. The later trend seems to be much closer fin pitch, but still in a small 'tube', restricting flow even more, & worse still 'choke' more at a comparative lower boost. The closer fin pitch which gives better cooling rates, would only increase performance if the tube length was shorter, as the cooling efficiency quickly exponentially decreases (we have placed probes @ 100mm increments along tubes of both air-air & dry ice intercoolers) & the pressure drop (more slowly) exponentially increases along the length of a tube, meaning there is a 'sweet spot' where cooling rate & pressure drop give maximum performance. Sorry guys, but our parchment 'for big is better' philosophy & the fact that the Chinese factories don't seem to have much technical inkling of how an intercooler works, means that allot of purchases will never give near the gains possible & some, well, they're just a waste of your 'cheap money' !!!
They really have there place in the market, are very good for anyone seeking a moderate power gain with a limited budget & for more gains than this, become increasingly more difficult to gauge if they will do the work you need , all this - is of course if you get a good one !
Intercooler Tech/Foto
http://rossracing.fotopages.com
