I'm a newbie with a 2001 996TT. Planning on upgrading to K16/K24 hybrid, europipe exhaust and ECU upgrade (already have stage 1 GIAC ECU upgrade and had to replace diverter valves ). My goal is about 600hp.

My questions are these:

1) aftermarket headers versus ported OEM headers? I realize this was discussed in another thread and the general opinion seemed to be to port the OEMs? Any disagreement?

2) What are the benefits and drawbacks (other than cost) of ceramic coating?

3) What air intake systems do people favor - I'm leaning towards Evo

4) Have any of you had issues with check engine lights using european 100 cell cats?

Thanks

 

Ceramic coating won't buy you much on this car- spend the time/money on other stuff. Never had any issues with 100 cell cats. At a stage IV the intake should be fine (people with GT700s have had issues with the MAF going but not at your level) and in terms of the "headers" you'l hear different camps.

1)Some will say "don't do headers" the factory ones are great etc... and just port them.
2)Others will say get some longer tube equal length headers with fancy merge collectors.

I've used both and I will say it depends on the application. Right now I have pretty large turbos and the factory headers choke. I gained quite a bit from jumping to larger primaries and so forth. On a K16/24 hybrid you're still dealing with a pretty small turbo. I've seen dynos that have shown about 20-25hp more and about 200 rpms less lag with different headers....

 

Sharkster: That 20-25hp more and 200rpm less lag on headers is on the K16/24 or with bigger turbos?

Thanks.

 

Sally those plots are from K24 turbo based cars. Somewhat similair to a K16/K24 set up. I think a K24 turbo would benefit more than a K16/24 would though since the K24 is inherintly more laggy to begin with.

 

Shark-

Which headers have you had the best results with?

 

Rad these ones here....
http://www.sharkwerks.com/products.php?pid=50

If you're interested in them don't get them today. Wait a day or two because they'll be "on sale" for Xmas shortly

 

the experts have answered but answer from a none mechanic track junkie is IF you WANT to do a header upgrade at that level most would recommend porting and EXTERIOR ceramic coating.
I dont think you will notice much of a difference and I agree the money is better spend in other areas. I have left mine alone.

 

I think on any K16 based turbo it's a moot point but certainly on the K24 based GT2s and X50s I've seen a good gain on dynos and even just driving. Those suckers are laggy and you do get back a couple of hundred RPMs of lag which is nice. The dynos show no loss in torque down low (if they were longer tube then they would loose) and from the mid-to-top end a decent 20-30hp gain on a stage IV.

 

I've wondered about this recently...

Originally I assumed that larger headers would get the additional air (after upgrades, higher boost , etc) out of the enigine easier, therefore more HP.

Then I considered that unlike a NA eninge, the turbo engine may need the air speed (velocity) created by the smaller primary tubes to assist will spool-up. But now that I've pondered the scenarios of larger primaries vs. more velocity thing for a few weeks, I'm back to my original thought that the larger tube headers would be a benefit on a car with K24 turbos and some mods.

The larger tubes will allow more air, and easier air flow for cars that need to get more air out of the engine (modded cars), and the velocity is really created at the header collector and turbo inlet anyway. So, more air volume via larger headers would equal more velocity at the turbo inlet.

For each person/car, it's really just a matter of determining how much air can be moved through the stock headers, and at what point your car will reach that barrier? After closely looking at my stock headers, I think any of the aftermarket 41mm or 44mm headers would offer an improvement once a few mods have been done.

I really don't see any downside to larger headers other than cost vs. necessity for each individual application.

 

As far as headers go, I've always liked 'em. Typically they're very low involvement; you can even watch SportsCenter if you like. Plus they're so much less complicated. No changing the sheets or even necessarily getting a room. No worries about birth control, pregnancy, or even pleasing your partner. It's typically anywhere from 50-120% of the pleasure, with very little actual "cost" involved, and no other mods required. But, as Sharky said, your results will depend largely upon the application . . .

 

I need to do something to help with the lag of my x50 k24's!

 

[quote=sharkster]Ceramic coating won't buy you much on this car- spend the time/money on other stuff. Never had any issues with 100 cell cats. At a stage IV the intake should be fine (people with GT700s have had issues with the MAF going but not at your level)quote]

When you say the intake should be fine do you mean the stock intake or EVO V-flow? Have you heard of any problems using the Vflow? Someone on another thread said it burned out his MAF or something?

Thx

 

[quote=rad]Hey Rad,

Actually the V-Flow should be a-ok/fine on your set up. People have killed MAF's only on the GT kits but not at the other levels. But you'll be fine either with or without it

 

That is an instant classic +1 rep... Kevin

 

rad have evo air box no probs at all get the paper filter alex has em (sharkwerks) also have 01europipe loud is great you will love it...