Turbo outlets: SPD vs AMS

[MudLovingFJ]

Any input on turbo outlet adapters?

Stock: 2.0625” or 52.4mm
SPD: 2.3125” or 58.7mm
AMS: 2.52” or 64mm

I’m hoping someone has run stock > SPD > AMS and has real world feedback.
I have the SPD adapters sitting in the garage in the box waiting to be installed, I’ll be picking up the AMS adapters on the current group buy going on the F150 forums. More than likely I will be installing the AMS units and mating them to SPD catted downpipes and stock exhaust.

 

[titanjc]

I'm interesting in feedback on these as well. I know the benefits of turbo adapters are highly debated, but the AMS group buy pricing is almost too good to pass up, and they offer a larger diameter than the SPD version.

 

[MadMaxx]

AMS, bigger is better.

Best would be to find a Downpipe that ditches the adapters as a whole and bolts directly to the Exhaust Housing. IIRC, the COBB ones do this, but they've been discontinued, so you'll have to find some NOS ones, if there are any out there.

 

[MudLovingFJ]

I wasn’t aware the Cobb downpipes ditched the adapters and bolted straight to the turbos, interesting.

 

[cwylie]

Not sure why people are worried how large the adapters are when the exhaust housing is the restriction. I had the cobb downpipes and the engine was far less responsive down low. Anything you think you gained by adapters is in your head.

 

[MudLovingFJ]

Not sure why people are worried how large the adapters are when the exhaust housing is the restriction. I had the cobb downpipes and the engine was far less responsive down low. Anything you think you gained by adapters is in your head.

Thanks for chiming in, that’s what I wanted to hear.
I’m worried the larger AMS adapters will lose low end torque but gain high end horsepower.
If you could do it again what would you run?

 

[MadMaxx]

Not sure why people are worried how large the adapters are when the exhaust housing is the restriction. I had the cobb downpipes and the engine was far less responsive down low. Anything you think you gained by adapters is in your head.

Were you tuned for the Cobb DP's or no?

You shouldn't have lost anything down low. Should have picked up a nice amount, and been a screamer up top.

 

[cwylie]

Yeah I had the Cobb tuner at the time. I recently switched to a custom tune from gearhead because I have a forged bottom end. Matt was willing to push it a little harder so I picked up some power for sure. Im running stock adapters and downpipes. Matt said there I could potentially pick up a little from a catless down pipe but I dont think it would be worth the noise. Im very happy with how the truck runs currently.

 

[xrocket21]

Thanks for chiming in, that’s what I wanted to hear.
I’m worried the larger AMS adapters will lose low end torque but gain high end horsepower.
If you could do it again what would you run?

you are thinking n/a, not turbo. they are different.

 

[xrocket21]

Not sure why people are worried how large the adapters are when the exhaust housing is the restriction. I had the cobb downpipes and the engine was far less responsive down low. Anything you think you gained by adapters is in your head.

Anything you think you lost with downpipes is in your head. This isnt a n/a engine where scavenging is important post turbo.

The most efficient turbo exhaust is none. Bigger is always better, post turbo.