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Acceleration Feel After Uprading Intercooler

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Tacoma, WA, USA
#1
Have any of you noticed that acceleration feels different after upgrading the intercooler? My FiST feels like it doesn't pull quite as hard after upgrading to a CPE IC. The e30 tune still blows my tires off but it feels less frantic. I thought maybe I had a boost leak from not tightening the clamps enough, but I'm still hitting close to 25 psi of boost on a warm day. I don't think the car is actually slower, I think it's just different. Wondering if anyone else has noticed a change after upgrading?
 


TyphoonFiST

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#2
Could be a pressure drop across the core itself. Most cores will be no more then a .5 pressure drop on a quality unit. Some that are not really thought out well will drop more across the intercooler core therefore decreasing the snappiness.
 


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#3
seemed the same to me. and as crazy as it seemed I had progressed to the point with new goodies a new plugs were necessary. one range colder and a tighter gap. not sure what it was all about but now it is crisp again.
 


TyphoonFiST

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#4
The tuner most likely be able to address your needs if you tell them what you are looking for with adjusting throttle response.
 


OP
P
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Thread Starter #5
Could be a pressure drop across the core itself. Most cores will be no more then a .5 pressure drop on a quality unit. Some that are not really thought out well will drop more across the intercooler core therefore decreasing the snappiness.
The pressure drop causes the turbo to spool slower right? Maybe I'm just feeling that. The CPE is way bigger than stock, but it seems like it is really well designed
 


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Destin
#6
That's exactly correct, what you're feeling is turbo lag. We talk a lot about boost threshold with larger turbos and hybrids but there's almost no discussion on here about turbo lag experienced from various intercooler/piping options.
There's probably a way to quantify boost lag timing but it seems to be a lot harder to measure than changes in boost threshold which are easily seen when comparing dyno runs.


Most relevant bit starts 1:52
 


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Location
Twin Falls, ID, USA
#7
Have any of you noticed that acceleration feels different after upgrading the intercooler? My FiST feels like it doesn't pull quite as hard after upgrading to a CPE IC. The e30 tune still blows my tires off but it feels less frantic. I thought maybe I had a boost leak from not tightening the clamps enough, but I'm still hitting close to 25 psi of boost on a warm day. I don't think the car is actually slower, I think it's just different. Wondering if anyone else has noticed a change after upgrading?
I have noticed a similar change after upgrading my hot-side charge pipe to c-PE (which has a much larger ID and volume than OEM). I am on a stock turbo and a conservative tune so I am sure the apparent change is less dramatic then what you're feeling but I noticed a latency added to my throttle. Not much, but enough that I could notice in daily driving. When going WOT and the turbo is at full boost I noticed more efficiency but less instantaneous throttle response. After watching the video that @LargeRubberFist posted it would make sense that this is turbo lag.
 


OP
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Thread Starter #8
I have noticed a similar change after upgrading my hot-side charge pipe to c-PE (which has a much larger ID and volume than OEM). I am on a stock turbo and a conservative tune so I am sure the apparent change is less dramatic then what you're feeling but I noticed a latency added to my throttle. Not much, but enough that I could notice in daily driving. When going WOT and the turbo is at full boost I noticed more efficiency but less instantaneous throttle response. After watching the video that @LargeRubberFist posted it would make sense that this is turbo lag.
Thanks for the input. I was paranoid, so I'm glad other people have had a similar experience!
 


the duke

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#9
I have noticed a similar change after upgrading my hot-side charge pipe to c-PE (which has a much larger ID and volume than OEM). I am on a stock turbo and a conservative tune so I am sure the apparent change is less dramatic then what you're feeling but I noticed a latency added to my throttle. Not much, but enough that I could notice in daily driving. When going WOT and the turbo is at full boost I noticed more efficiency but less instantaneous throttle response. After watching the video that @LargeRubberFist posted it would make sense that this is turbo lag.
It's larger volume. More volume for air to occupy. Simple physics.

If you want to get smart about it you could start playing with tubing diameter, path lengths, bends, etc. to try and keep the airspeed up while reducing the piping size. Colder side piping could use a smaller piping diameter as the air is higher in density. The pre-intercooler density is greater than post-intercooler, so 1 psi between the two contains differing amounts of actual air. The airspeed between the two is also lower, as the cooler denser air is moving slower than the less dense, hotter air (Less energy). That doesn't even get into what's happening in the intercooler and how the pressure/airspeed changes in the core, or more importantly how the entrance/exit of the intercooler/tanks are designed (I want to do some testing on modified inlet/outlets of intercoolers).

This is one of those ideas if I had a shop I'd love to play around with this stuff for a week, but I would guess on a non-race car it's not worth the hassle for the terribly small gains. F1, sure. These cars, nah.
 


Last edited:

gtx3076

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#10
It's larger volume. More volume for air to occupy. Simple physics.

If you want to get smart about it you could start playing with tubing diameter, path lengths, bends, etc. to try and keep the airspeed up while reducing the piping size. Colder side piping could use a smaller piping diameter as the air is lower in density. The pre-intercooler density is greater than post-intercooler, so 1 psi between the two contains differing amounts of actual air. The airspeed between the two is also lower, as the cooler denser air is moving slower than the less dense, hotter air (Less energy). That doesn't even get into what's happening in the intercooler and how the pressure/airspeed changes in the core, or more importantly how the entrance/exit of the intercooler/tanks are designed (I want to do some testing on modified inlet/outlets of intercoolers).

This is one of those ideas if I had a shop I'd love to play around with this stuff for a week, but I would guess on a non-race car it's not worth the hassle for the terribly small gains. F1, sure. These cars, nah.
I followed a guy with a mazdaspeed that removed his intercooler and used methanol to cool the charge. Boost came in much faster, but obviously he was going through meth very quickly.

Sent from my SM-G930T using Tapatalk
 


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Location
Southeast
#11
So is a tune the actual solution here? Or going with a smedium sized intercooler?
Makes me weary of getting a larger intercooler if I’m going to lose the driving characteristics.
 




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