I need a measurement

[supraluke]

My STi's header cracked and i'm having the flex sections removed with a straight section. I need the distance between the two studs on the exhaust header. I can't use my cracked header measurement because the broken flex section moves around.

http://i188.photobucket.com/albums/z291/benvr6passat/forums/Random/HeaderSpacing.jpg

Yes, I know the flanges are drawn backwards. I'm an idiot. I'm hoping one of you have a spare header you can measure the two holes center to center for me so I can give the measurement to the welder.

Thanks

[sperry]

I wouldn't try to replace that with a non-flex pipe. You'll never keep the cross-pipe gaskets sealed up as the headers expand/contract drastically when they heat/cool. Plus it would be better to measure center to center on the studs on the heads themselves, as a set of headers off the car will have moved around a bunch just by being off the car.

I've actually got a stock crosspipe with header wrap on it in fine condition I'll unload for cheap if you want it.

[supraluke]

Originally Posted by sperry

I wouldn't try to replace that with a non-flex pipe. You'll never keep the cross-pipe gaskets sealed up as the headers expand/contract drastically when they heat/cool. Plus it would be better to measure center to center on the studs on the heads themselves, as a set of headers off the car will have moved around a bunch just by being off the car.

I've actually got a stock crosspipe with header wrap on it in fine condition I'll unload for cheap if you want it.

I liked my APS header untill this happened. The newer APS headers got rid of the flex parts on there newer design, and many other companys like Full-Race don't use them either. I'm sure your right about measuring center to center on the heads, but how would I go about doing that? Any ideas?

I gave away my stock exhaust manifold and up-pipe to a WRX owner long ago so the cross section you have wouldn't be enough to fix my problem.

[Dean]

They all have some sort of expansion slide sleeve or flex. You can't just put in a solid section. Why not just pick up a replacement flex section at Summit and get it welded in?

[Kevin M]

Originally Posted by Dean

They all have some sort of expansion slide sleeve or flex. You can't just put in a solid section. Why not just pick up a replacement flex section at Summit and get it welded in?

That sounds a lot more difficult than just getting a complete OE header or the GrimmSpeed combo potentially. Then there's the ghetto fabulous factor.

[supraluke]

Originally Posted by Dean

They all have some sort of expansion slide sleeve or flex. You can't just put in a solid section. Why not just pick up a replacement flex section at Summit and get it welded in?

Well, APS got rid off there flex section completely. Similar to this one.




worried about putting another flex section in because I think this will just end up happening over again. It might crack without it as well, but I just thought that since APS got rid of theres flex section and I seen full-race not use one, that maybe not having one would be better.

Thanks for the replys.

[Dean]

That is a 4 long-2 header with a 2-1 up-pipe mostly ELH. Isn't yours a short path ULH with a single crossover, single up-pipe? Completely different design and expansion characteristics if it is.

You would rather have a flex fail than a weld and Summit may have a better designed Flex than what you had. What diameter tubing?

You could also fab a slide sleeve inside a flex to maximize life if you can't find one of a similarly sturdy design.

[supraluke]

Originally Posted by Dean

That is a 4 long-2 header with a 2-1 up-pipe mostly ELH. Isn't yours a short path ULH with a single crossover, single up-pipe? Completely different design and expansion characteristics if it is.

You would rather have a flex fail than a weld and Summit may have a better designed Flex than what you had. What diameter tubing?

You could also fab a slide sleeve inside a flex to maximize life if you can't find one of a similarly sturdy design.

My APS equal lengh header is designed exactly like the one above with the 4 long-2 and 2-1 up-pipe except I have a flex section in each of the two straight sections (staggered).

http://www.airpowersystems.com/wrx/a...02/headers.htm

I figured full-race didn't use the flex's and APS got rid off the flex section's in their updated design that not having the flex sections might be better than having them. The ID of the tubing is 1-7/8" which i think is larger than most. Summit sells 1.75" ID flex (which is too small) and 2" ID flex (which might be too big). I really hate this header considering how well it's held up (2 welds have already been repaired) compared to how much I original paid for this "high quality part" I hate to just give up on it and throw it away and buy another.

[sperry]

The unfortunate reality is, on a modded turbo car, flex pipes before the turbo are basically wear items. You just can't run 1600F exhaust thru them day after day and expect them to survive.

An ELH might have better luck w/o the flex section though because the expansion angles might be different. I don't really have any experience with them. But trying to convert from flex to straight may not work. Certainly a sleeve would be better, not only because it handles expansion, but because you might have an easier time getting the repaired header to fit.

I'd give the repair a shot simply because the gaskets I was talking about that would leak on the ULH don't exist on the ELH. Just don't drop a ton of money trying to fix it, because you might end up just needing a whole new header.

[Dean]

OK, did not realize yours was EL. Best way to fit solid would be to cut flexes out and tack or full weld solid in place with the headers bolted to the block. Unlikely to get a good fit otherwise no matter how well you measure anything IMHO.

I'd still be tempted to do flex over sleeve though.

Might also contact APS and see if you can get a deal on an upgrade to V2 no flex bit.

[supraluke]

Originally Posted by sperry

The unfortunate reality is, on a modded turbo car, flex pipes before the turbo are basically wear items. You just can't run 1600F exhaust thru them day after day and expect them to survive.

An ELH might have better luck w/o the flex section though because the expansion angles might be different. I don't really have any experience with them. But trying to convert from flex to straight may not work. Certainly a sleeve would be better, not only because it handles expansion, but because you might have an easier time getting the repaired header to fit.

I'd give the repair a shot simply because the gaskets I was talking about that would leak on the ULH don't exist on the ELH. Just don't drop a ton of money trying to fix it, because you might end up just needing a whole new header.

Thanks for you help. The repair would take around 3 hours and it's 90 bucks and hour. A new quality header cost between $1000 to over $2,000 like the one above (http://www.full-race.com/catalog/pro...oducts_id=1942

I don't want to gamble $300 bucks but spending another $1000 to rebuy another one is something I want to do even less.

[supraluke]

Originally Posted by Dean

OK, did not realize yours was EL. Best way to fit solid would be to cut flexes out and tack or full weld solid in place with the headers bolted to the block. Unlikely to get a good fit otherwise no matter how well you measure anything IMHO.

I'd still be tempted to do flex over sleeve though.

Might also contact APS and see if you can get a deal on an upgrade to V2 no flex bit.

I original tried to bring my car into a couple of quality welding shops. Nobody wanted to see me unless I took the header off the car and hence, need the measurements.

My APS header is a V2. My V1 weld's cracked and they replaced it. My V2's weld's cracked, they told me I was no longer under warrenty. V3's cracked as well and V4 got rid of the flex sections completely and had no more problems (that I know of). It's all moot anyways because APS doesn't import to the USA anymore anyways or seem to make parts for Subaru's anymore either.

[Dean]

Originally Posted by supraluke

I original tried to bring my car into a couple of quality welding shops. Nobody wanted to see me unless I took the header off the car and hence, need the measurements.

That is crazy. Anybody who understands geometry should know that the odds of getting it right so all 9 studs/bolts slide on and flanges mate flat on a bench in 3 axis without a jig which they do not have is basically zero.

Guess you need to find a better shop or a shop with a long block out on an engine stand you can weld on after cutting out the flexes.

[supraluke]

Originally Posted by Dean

That is crazy. Anybody who understands geometry should know that the odds of getting it right so all 9 studs/bolts slide on and flanges mate flat on a bench in 3 axis without a jig which they do not have is basically zero.

Guess you need to find a better shop or a shop with a long block out on an engine stand you can weld on after cutting out the flexes.

Yeah, your right. I think flex sections will have to work or not at all as there will be no way to line up all nine bolts unless it's absolutely perfect. I'll get online and hopefully find something that will work.

Thank you Dean and Sperry for your help.

[sperry]

Originally Posted by supraluke

I original tried to bring my car into a couple of quality welding shops. Nobody wanted to see me unless I took the header off the car and hence, need the measurements.

My APS header is a V2. My V1 weld's cracked and they replaced it. My V2's weld's cracked, they told me I was no longer under warrenty. V3's cracked as well and V4 got rid of the flex sections completely and had no more problems (that I know of). It's all moot anyways because APS doesn't import to the USA anymore anyways or seem to make parts for Subaru's anymore either.

On an aside... virtually all aftermarket headers fail eventually on a car that's run hard. I remember talking to Mike Warfield at GST about their L time attack car... at the time they had just switched back to stock headers because it was the only thing that could stand up to the punishment.

I ended up doing the same thing. I sold my Gruppe-S headers and went back to stock, though I did it because the Gruppe-S headers wouldn't clear the Cosworth oil pan I got. But in the long run, I think the OEM headers are the most reliable, even with that flex joint that will eventually fail. Grimmspeed does porting/polishing/coating of stock headers that seem to be the best of both worlds: aftermarket performance, stock reliability. I should have a set as soon as Kspeed gets back to me on a price.

[supraluke]

Originally Posted by sperry

On an aside... virtually all aftermarket headers fail eventually on a car that's run hard. I remember talking to Mike Warfield at GST about their L time attack car... at the time they had just switched back to stock headers because it was the only thing that could stand up to the punishment.

I ended up doing the same thing. I sold my Gruppe-S headers and went back to stock, though I did it because the Gruppe-S headers wouldn't clear the Cosworth oil pan I got. But in the long run, I think the OEM headers are the most reliable, even with that flex joint that will eventually fail. Grimmspeed does porting/polishing/coating of stock headers that seem to be the best of both worlds: aftermarket performance, stock reliability. I should have a set as soon as Kspeed gets back to me on a price.

I ending up having a new flex piece put in. I wasn't happy that isn't wasn't stainless but it was all that Summit sold. Ending up costing me $200 bucks total. I hope it holds up. If you want to use the stock headers, take a look at this EQ Tuning crosspipe:



Kind of makes me wish I kept my stock ones too.

[Dean]

That is pretty cool and stealthy to boot.