Opinions on downpipes??

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Rednose

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@Rednose - I totally co-sign that. Makes complete sense to me also. I’m just wondering if the DP’s will cause a code and lingering check-engine light....??

The only code I got was the shutter code which has nothing to do with the Dp, but like @zombiekiller said no codes from the SPD catted Dp.
 

WHYUMAD

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The only code I got was the shutter code which has nothing to do with the Dp, but like @zombiekiller said no codes from the SPD catted Dp.

But is there any benefit to doing the catted SPD DP’s other than changing a part? The flow isn’t improved much at all, at least that’s what was said. The adapters make the difference... but really, is there any benefit doing the catted DP’s too? just curious before I do this mod.
 

Rednose

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But is there any benefit to doing the catted SPD DP’s other than changing a part? The flow isn’t improved much at all, at least that’s what was said. The adapters make the difference... but really, is there any benefit doing the catted DP’s too? just curious before I do this mod.

Other than a better flowing air and higher sound I cant specify any additional benefit but in my experience with the catted Dp I had it on the truck with tune and without. I noticed without having the tune the sounds is there but I felt the truck is losing back pressure and dose not have a very strong top end compering it with the tune installed.

On papers it doesn't make a difference but in real life scenario or a race wining by a fender is considered a win and this is exactly what the dp does giving you the nose win or the slow walk away when your neck to neck with the other car.

Ex: Having 2 manual trans cars both have the same bolt on kit running the same hp numbers but one of them runs a racing clutch, and 90% of the time the one running the racing clutch will reach the end line first.

Sorry if what I said is complicated but I tried to simplify in the best way.
 

Nood1es

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@Nood1es - what kind of dps, and will it cause a code???

spd catted, no codes. Catless will cause codes obviously..but you either have your tuner code it out(been mentioned mpt won’t) or use anti foulers.

Same dyno a week apart, same tank of gas. Diff was dp with tune and I gained +31wtq. No hp gain. Just something to think about and you can def feel that gain. I guess it’s not same day dyno so I’ll let you decide.
 

xrocket21

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Other than a better flowing air and higher sound I cant specify any additional benefit but in my experience with the catted Dp I had it on the truck with tune and without. I noticed without having the tune the sounds is there but I felt the truck is losing back pressure and dose not have a very strong top end compering it with the tune installed.

On papers it doesn't make a difference but in real life scenario or a race wining by a fender is considered a win and this is exactly what the dp does giving you the nose win or the slow walk away when your neck to neck with the other car.

Ex: Having 2 manual trans cars both have the same bolt on kit running the same hp numbers but one of them runs a racing clutch, and 90% of the time the one running the racing clutch will reach the end line first.

Sorry if what I said is complicated but I tried to simplify in the best way.

back pressure is for N/A vehicles

the best exhaust for a turbo vehicle is open air after the turbo. Scavenging is a non-issue post turbine
 

WHYUMAD

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Other than a better flowing air and higher sound I cant specify any additional benefit but in my experience with the catted Dp I had it on the truck with tune and without. I noticed without having the tune the sounds is there but I felt the truck is losing back pressure and dose not have a very strong top end compering it with the tune installed.

On papers it doesn't make a difference but in real life scenario or a race wining by a fender is considered a win and this is exactly what the dp does giving you the nose win or the slow walk away when your neck to neck with the other car.

Ex: Having 2 manual trans cars both have the same bolt on kit running the same hp numbers but one of them runs a racing clutch, and 90% of the time the one running the racing clutch will reach the end line first.

Sorry if what I said is complicated but I tried to simplify in the best way.

Makes sense... so it does make a slight difference. Obviously the non-catted would yield better results, but that’d be way too loud imo & I’m not looking to throw codes. I’m gonna probably do the DP’s when I do the turbo adapters then. Thank you.
 

Rednose

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back pressure is for N/A vehicles

the best exhaust for a turbo vehicle is open air after the turbo. Scavenging is a non-issue post turbine

What I know is turbo equipped engines will have back pressure. For example when your engine gets to a point that it does not make enough power and boost and one of the reasons could be too much of back pressure.

Which means less back pressure equals more power.( I might be wrong )

And I was just trying to describe how it felt when I had the dp with no tune.


Sent from my iPhone using Tapatalk
 

MudLovingFJ

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I’ve heard it go both ways with downpipes on gen2 Raptors; they’re needed when you’re trying to get the maximum out of the truck OR they won’t do anything for you at all and you’re wasting your time.

Personally, I bought SPD downpipes and turbo adapters and will be tuning the truck through MPT hopefully.

I think the bigger argument on the forums is whether an aftermarket intake is worth the investment or not.

With all that being said, there is likely more power to be had by going FMIC vs downpipes. Only because +40° intake manifold temps over ambient kill more power than downpipes can ever release.
 
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