Are you sure that at your power level that is even necessary. do you really think that there is so much a difference. Problem is that with IC's who knows where the difference will be. Is there anyone with the same kit who has had both types of intakes and compared them?

I would say that you log your Inj Duty Cycle, AFR's, boost Presure before and after. If the first two factors change much then that may be the cause of your increased performance not necessarily the hardware change. You can do this by leaving less a safety margin right?

I hope your changes give you more power, sucks to spend 8k and gain 2 tenths of a second.

look at the evoms GT30 cars. They don't have those intakes and they have 3.5 inch IC's and do you think you will be at those power levels?

 

I agree with Todd, thicker is not always better when it come to cooling. Concerning Sean's original question, the solution to his question involves calculating various properties, such as velocity, pressure, density, and temperature, as functions of space and time. Referencing my build, I increased the size of my intercoolers for two reasons. The first was to reduce the friction coeffecient by increasing the diameter of the IC in hopes of improving the responsiveness of my turbos and secondly decreasing the temperature charge in an attempt to maximize total hp. I would defer to the two Todd's for what size of an IC you need.

Good luck
Robert

 

I have just moved over to a Porsche from years of messing with Cosworths where after basic stage 1 mods you fit what we call a RS500 size cooler. To give you an idea of the size this is a 60mm core fitted to my old car that had a turbo around the size of a GT30, and there was no change in lag from the original cooler that is around the size of a 996 cooler.

 

Simple answer, if it's not Secans, it's cheap and so are you

What real world results are you using to insinuate there is no additional lag? 60-130 is not a legitimate test of lag especially when a lot of guys are power shifting, there is no time for lag, so the times may not be affected, or actually improve. I could power shift my old 800whp corvette with rear mounted turbos and not get lag, so that doesn't tell you much. Are there dyno runs with boost logs at certain rpms? That is the only way to really tell.

A great test would be a no shift, one gear 0-top of 3rd or 4th. The car with the least lag will get there first.

I would be glad if the bigger cores did not make lag because they in theory can handle more heat and would be great for the road course, but from what has been said, that does not seem to be the case.


Time for Secans.

 

Going to have to put the 20K towards other things.

Just look at the SPI Sledghammer package...putting down 700 whp on stock internals/pump gas and a key piece of that package are the 6 inch IC's.

 

I hate to disagree with you Sean, but the ICs are not the key to that package.

 

They are not the key so much as a piece of the puzzle, Rob (I said "a key" not "the key").

The standalone is the centerpiece, but I guarantee it would not make the big power on 3.5 inchers.

 

I will guarantee that a 700 package will not vary in peak hp on a dyno with changing EVOMS 3.5 with 5 in who ever. The EVOMs 3.5 is a DAMN good IC for its size.
Robert

 

I think Sean wold do just fine on the Evoms ICs...

 

Here's the question I need answered are 5" in any way detrimental for performance compared to 3.5"? (eg. less spool time or cooling ability due to thickness & pressure.) So if you could have 5" vs 3.5 with 24/18's which would you use regardless of price. Will the cooling ability of the 5" be better? These questions are based on using 24/18 turbo's. At what point does heat soak become a factor?

Sorry if any of these questions are silly,I am trying to learn about the benifit of IC's.

 

most bar and plates cores are superior to tube and fit( assuming they are made by a good company).. with that said.... look at the end tank design on a stock IC.. its scary...
good cores with decent end tanks is a win win situation over what you already have.... the cooling is what most forget... yet a very important factor when it comes to HP...

here is my 3.5 direct replacement (no expensive hoses needed) prototype...
3.5x9x14 BEll core.








CnCed custom end for direct fit hoses...

 

Markski thank you for the above info.

 

But peak hp does not tell you anything about lag. Could be a lag monster and make tons of power.

 

Right. Lets see the dyno, not for the numbers, but for the curves...

 

actually for drag racing a lag monster is a good thing

having said that I am getting secans, and since they are 5 times better than everything else I am putting one in my turbo and the other in my VEETEC!!!!! that leaves 2.5 times better than all else.