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Downpipes & Best Practices

KrackaC8

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Looking at lowers - I see AMS is using studs like oem for installation. Also AMS does not have a logo plate tack welded to the pipe - a plus for coating.

for the brands using standard bolts for installation, would you install all the nuts on the bottom side or keep same direction as stock?

for the logo plates, do you remove or just coat over them?
Bolt heads on top/nuts underneath (where it fits to do so - note the angled flange & o2 bung).

The logos get coated with the rest of the pipe. Or, you could request they get masked off and not coated if you want the contrast to highlight the brand.

The AMS brand commands a huge premium considering Spool sells their 3" non-resonated LDPs for $300 less ($199 vs. $499).
 
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thesilverbullet

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Bolt heads on top/nuts underneath (where it fits to do so - note the angled flange & o2 bung).

The logos get coated with the rest of the pipe. Or, you could request they get masked off and not coated if you want the contrast to highlight the brand.

The AMS brand commands a huge premium considering Spool sells their 3" non-resonated LDPs for $300 less ($199 vs. $499).
will using bolts instead studs make installation a two person job?

i am concerned with the coating peeling off with masking or coating over the logo plate. seems like the coating would be more robust without the logo plate.
 

KrackaC8

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will using bolts instead studs make installation a two person job?

i am concerned with the coating peeling off with masking or coating over the logo plate. seems like the coating would be more robust without the logo plate.
Bolts vs. studs shouldn't materially change the installation difficulty one way or the other. Often times, I actually prefer bolts vs. studs in confined work spaces.

The coating durability will not be impacted either way. Excessive heat and using too low of a temp rated coating are the concern points, along with quality of prep/workmanship of course. You're going to want something rated in the 1800-2000F range; stay away from the 1600F shiny metallic silver being that close to the turbo/cat.

My coated LDPs should be done late this week but due to travel I likely won't be able to pick them up until early next. I'll post pics as soon as I have them back.
 

KrackaC8

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I picked them up from the coater on the way home from the airport today!

SPOOL 3.0" resonated LDPs

Inlets measured 2¼" ID and outlets at 2⅞" ID. The titanium coating looks fantastic, especially as this is the highest temp rating they offer.

1000005367.webp
1000005368.webp
1000005369.webp
1000005370.webp
1000005371.webp
1000005372.webp
 

thesilverbullet

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Very nice - that looks good.

thanks for the measurements. is the inlet pipe OD a smaller dia. - machined down on the flange side and flared out on the resonator side?

I can’t wait for the upper cat outlet measurement
 

thesilverbullet

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KrackaC8

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Very nice - that looks good.

thanks for the measurements. is the inlet pipe OD a smaller dia. - machined down on the flange side and flared out on the resonator side?

I can’t wait for the upper cat outlet measurement
Regarding the inlet, the pipe matches the flange then tapers larger into the resonator. My guess is they started with a 2.5" pipe pre-resonator and pinched/flared it. You can see it in the pictures if you look closely. It's frankly exactly how I'd design mine if I were custom fabricate a set.
 

KrackaC8

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thesilverbullet

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is this because the upper outlet is ~2.25?
 

KrackaC8

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KrackaC8

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Spool products fabricated in-house?
They claim in-house here in Houston. From handling theirs and B6A pipes in my own hands, it's a pretty obvious difference.
 
 






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