I have Mines performance manifold (w/ external wg) and a downpipe that I had custom made. The turbo is a 50trim 48a/r turbo and the motor has springs retainers, rods pistons, and all the ARP bolts. My questions are:

1. What are the draw-backs of heat wrapping the manifold? Cracking, loss of longevity?
2. What kind of IAT difference will it make?
3. How does that translate to HP?

 

1. It can trap moisture and cause rusting (although you can use sealants/coatings to prevent this)
2. Not sure but definately not a HUGE difference... it's main benifit is lowering underhood temps and keeping heat in the turbo/DP to keep exhaust gases flowing well.
3. it doesn't. You may spool a little faster the IAT may drop a little but it's not like you put it on and gain 20hp or anything like that.

 

I dont know how much I believe the trapping moisture thing.....turbo pipes get hot enough to evaporate any moisture that might be in the wrap after a good soaking from a puddle.....maybe if the car sits alot in a damper climate but for the most part I just dont believe it to be an issue.....Manifolds go through alot of abuse just from the heat cycles and need to be replaced after a while anyways. IMO they are a wearable item just like the rest of the exhaust. I have seen manifolds after the wraps have been removed and they do have some surface rust on them but nothing I would believe to harm the structual integrity of them.....

I dont know where this rumor of wraps causing problems came from, maybe the V8 crowd because most of their headers were just mild steel and I could see that being an issue. almost all the tubulars you see these days are SS.

I always suggest contacting the manufacturer and doing what they suggest for heat retention just to avoid voiding your warranty

 

Nice! I wouldn't mind spooling a bit faster. I can just get some for free if I want it. I will definitely ask Mines about it though. Thanks.