Yes, porting the stock headers produces very good results, did you ports yours, Tim?

 

congrats!! thats awesome you should be in the mid 5's that must feel wild!! i did not port them yet.. im waiting for my ic's to be built..then ill do the port&piggyback pump

 

I ported mine myself and had a local shop...(Process coatings) ceramic coat the externals for $150. They came out great. I must say if you are going to do the porting yourself set aside plenty of time

 

I agree... it does take a while! That stainless steel is HARD and so are the welds!

 

How much hp are you running?

 

Can someone define porting for me

 

Grinding material from header internals--to make cleaner(smoother) and bigger,wider,more open.

 

Rick the stock headers are not stainless they are cast.

and yes i think they do make a decent amount of a difference , i loved mine but moved to a external wastegate set up so i had to swap. or else i would of never sold them.

 

Any pics anyone before and after?

 

Cast... ? Which part??? Mine are steel with the factory part #'s stamped in the STEEL beginning w/996... Most steel pieces have the numbers stamped in them while cast pieces have raised numbers cast on the parts. I've worked in the auto industry over 30 years and I've never seen any cast parts with a weld on them (unless they were repaired.) My factory headers have several welds on them including a welded on flange... which is where I spent my time grinding. Cast pieces are one piece w/no welds... like heads, blocks or block halfs, transfer cases, transmission cases and most rear ends. Most vehicles w/serpentine belts have cast brackets to hold accessories like AC compressors, alternators & PS pumps which most are themselves a cast piece... Just... my 2 pennys

 

I would agree in saying that headers really make a difference for the larger turbos. When it comes to moving exhaust gas, you do want a certain runner and collector style to help spool the turbo up and be most efficient. Generally, headers on a stock K16 or K24 car might yield 8hp. On a 500HP car not that big of difference. However as you put the puzzle together, the addition will make sense. Remember that also Peak HP is not as important to some drivers as is the the low end torque gain or mid range RPM improvements for those road racing. I can say that adding headers will slightly change the exhaust note as well.

 

Why guess. Flow test the headers. From there you can use the available flow formula's to determine the maximum hp capable of being produced by using this part. Then make sure there is a match with the turbo's flow. Too much flow can be worse than too little flow when pairing header exhaust to turbo's.

 

What is the consensus on using headers with external wastegates?

 

What is the consensus on using headers with external wastegates?

 

Posted some photos 8 days ago. If only people would use the search tool...

https://www.6speedonline.com/forums/...positives.html