most aftermarket direct replacement cores are 3.5" tall. then the 4.5s", 5"s, and 6".
Stock is about 2.5"+. but its also tube and fin vs. bar & plate. Also look at the amount of plates in a core across.. some have only 11.... some 13.. and the $15K ones have 15 or even 16. that all matters... as well as the design of the core.. the cheaper end Asian ones have def. a less compacted design if you look thru the core... not to mention the end tanks... thats another story... you want the core to get air across the compete core not just the center... thus the end tank design does matter.... etc etc... bottom line is most of the vendors here sell really good products... each with some diff. approaches...
this is mine... 3.5s and 4.5s....






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Le mapping sera refait sur banc et non pas un ECU générique acheté tout fait (pas plus à un autre qu'à FVD d'ailleurs), donc pas d'obligation, mais merci de ta bonne intention.

 

Alright, enough of the french please.

 

Dont you speak french ruf? I know some words but i think they are all rude .

 

TPC has one of the best I/Cs out there

 

Product quality offered by Mark is awesome...Years ago,he was the first to get to 9s...show us some more photos mark...Are 4,5inch ics necessary for stock VTgs?or 3,5 would be fine?

 

I think Markski would agree with me.....if you're still running stock VTG's, or even upgraded VTG's, you will be fine with the 3.5" cores. When you're still using VTG's, the size of the core is not as important as it's efficiency. Bigger isn't always necessarily better. In order for a larger core to become efficient, you'll need to be pushing an ENORMOUS amount of air through (from a non-VTG turbocharger for example), much more then most modified VTG's are capable of.

 

Most tuned 997s do run a decent amount of boost... thus smaller turbos produce more heat then bigger turbos at the same boost level.... the smaller ones work harder ... produce more heat...
I found that our 4.5s work 12 degrees Celsius( on average) better over our 3.5s... I also found that its very hard to simulate the efficiency of a IC just by a dyno run... a 0 to 150mph for example showed me different results....
I also noticed that some discuss only the hight of the ICs... although there are pluses and minus to both.. the width as well as the amount of bars does matter too....
All in all the 3.5s available my most tuners are good quality... there are some differences between them ... like ease of install, price, what's included in the kit... etc etc...
Just generalizing.... not making any claims that one is better over the other...

 

I don't know any words but I do know some gestures.

Er, on second thought, maybe it's Italian that I know.