MK7 "Random / "Stupid" Questions Thread"

[EpicTech]

Totally valid…. But I’m at the “can’t” point…maybe down the road

Still saving myself, I'm about halfway there but I'm getting MPI and RS3 LPFP at the same time. To me it only makes sense to do both. I dont need to the LPFP upgrade to push the IS38, but I'll need it later for sure.

 

[swcrow]

Still saving myself, I'm about halfway there but I'm getting MPI and RS3 LPFP at the same time. To me it only makes sense to do both. I dont need to the LPFP upgrade to push the IS38, but I'll need it later for sure.

I’ll use the hpfp to get as much out of the Garrett, then look at mpi and do it again

 

[Nineeightyone]

Long-term IS38 + E30 (or maybe flexfuel up to E85 if Cobb ever brings it), what all is necessary other than MPI/what supporting mods? Will the stock LPFP be fine for E tunes? I'm still not convinced that I need more power, BUT looooooooooooong term when the IS20 starts to give me reason I'd look at IS38/+ or maybe Garett comparable options

 

[scrllock]

Long-term IS38 + E30 (or maybe flexfuel up to E85 if Cobb ever brings it), what all is necessary other than MPI/what supporting mods? Will the stock LPFP be fine for E tunes? I'm still not convinced that I need more power, BUT looooooooooooong term when the IS20 starts to give me reason I'd look at IS38/+ or maybe Garett comparable options

stock LPFP is fine for e30, hit-or-miss for e85.

 

[EpicTech]

Now I am wondering about what my duty % is on the stock LPFP pushing the IS38 lol. I'm sure it's safe, just wondering how hard it's working.

 

[Diggs24]

It's running at 91% (max I go on stock LPFP) to ensure HPFP receives maximum fuel pressure. Without a sensor on the low side there's no way to tell how it's doing. HFPF pressure is best indicator, but that only tells you if the overall pressure is good, not if one pump or the other is not pulling it's weight. With MPI you get visibility to the whole system pressure.

 

[EpicTech]

roger that, all the more reason to go MPI.

 

[StorableComa]

You can do OEM+ MPI for a pretty decent price. Some might say you spent half of what an MPI kit would cost with Manifold, fuel hose, clamps and everything else needed to make it plug and play, on HPFP internals.. Shoot me a PM if interested, I've got my kits ready to go currently and offering a discount early adopter price.

 

[swcrow]

For those that have wrapped their downpipes…. Did you use a degreaser to clean the DP before wrapping?

 

[victorofhavoc]

For those that have wrapped their downpipes…. Did you use a degreaser to clean the DP before wrapping?

Nope. Mine was new when I wrapped it though. I would recommend cleaning it fairly well, using some 600 grit sand paper to scuff it up, and painting with some header paint first.

Wraps can pick up water and cause the pipe to rust, so you want some high temp paint on there below the wrap, even if it's SS.

 

[swcrow]

Nope. Mine was new when I wrapped it though. I would recommend cleaning it fairly well, using some 600 grit sand paper to scuff it up, and painting with some header paint first.

Wraps can pick up water and cause the pipe to rust, so you want some high temp paint on there below the wrap, even if it's SS.

Excellent input. Never thought about that so I appreciate you throwing that out there.

 

[Maiden69]

Wraps can pick up water and cause the pipe to rust, so you want some high temp paint on there below the wrap, even if it's SS.

If it is SS the only way it will rust is if it was over heated while welding, the welder used the wrong wire, or it is an inferior SS quality, ie. not 300 series. Other than that, the hardware can rust if it is not SS as well. On very extreme conditions the SS may pit, or form some thin surface "rust", this easily cleans out with any iron contaminant remover, metal polish, or super fine steel wool.

I have wrapped SS headers, including in PR while living less than 2 miles from the sea shore and never saw actual corrosion of the tubing.

 

[victorofhavoc]

If it is SS the only way it will rust is if it was over heated while welding, the welder used the wrong wire, or it is an inferior SS quality, ie. not 300 series. Other than that, the hardware can rust if it is not SS as well. On very extreme conditions the SS may pit, or form some thin surface "rust", this easily cleans out with any iron contaminant remover, metal polish, or super fine steel wool.

I have wrapped SS headers, including in PR while living less than 2 miles from the sea shore and never saw actual corrosion of the tubing.

I invite you to Google around for other experiences and how marine applications deal with stainless steel.

There are varying degrees of quality in SS like you pointed out, and just being SS does not mean it "will not rust", even if it's high quality. Even two 3xx SS tubes from the same company can vary in the additives used to generate that stainless property. It's not just chromium. It can only resist corrosion for so long and then will eventually begin to rust. Using a wrap which will absorb water and retain it close to the downpipe (which externally with a wrap will reach higher temperatures than without) will ultimately cause corrosion.

Corrosion under wraps is why ceramic coating headers and downpipes became popular in the first place. Headers also are a bit different since they're more protected from water by belly pans. The downpipe is fairly exposed and will become saturated quickly. Even on race cars that see little rain and often use higher quality ss, I've seen them rust quite a bit.

https://forums.nasioc.com/forums/sh...ollow proper,create a rust-friendly situation.

https://www.reddit.com/r/WRX/comments/pgrts5
https://grassrootsmotorsports.com/forum/grm/learn-me-header-wrap/62168/page1/

https://www.unifiedalloys.com/blog/what-is-stainless-steel

https://www.meadmetals.com/blog/wil...the iron infused in,or in common terms — rust.

 

[JerseyDrew77]

I invite you to Google around for other experiences and how marine applications deal with stainless steel.

There are varying degrees of quality in SS like you pointed out, and just being SS does not mean it "will not rust", even if it's high quality. Even two 3xx SS tubes from the same company can vary in the additives used to generate that stainless property. It's not just chromium. It can only resist corrosion for so long and then will eventually begin to rust. Using a wrap which will absorb water and retain it close to the downpipe (which externally with a wrap will reach higher temperatures than without) will ultimately cause corrosion.

Corrosion under wraps is why ceramic coating headers and downpipes became popular in the first place. Headers also are a bit different since they're more protected from water by belly pans. The downpipe is fairly exposed and will become saturated quickly. Even on race cars that see little rain and often use higher quality ss, I've seen them rust quite a bit.

https://forums.nasioc.com/forums/showthread.php?t=898107#:~:text=Actually, if you follow proper,create a rust-friendly situation.

https://www.reddit.com/r/WRX/comments/pgrts5
https://grassrootsmotorsports.com/forum/grm/learn-me-header-wrap/62168/page1/

https://www.unifiedalloys.com/blog/what-is-stainless-steel

https://www.meadmetals.com/blog/will-stainless-steel-rust#:~:text=When the iron infused in,or in common terms — rust.

I thought high quality wraps are waterproof and help wick away water.

 

[swcrow]

DEI titanium wrap is what I’ll be using