Barnes
Well-known member
Don't forget that objects near an uncovered manifold will experience a large amount of heat flux due to radiative heat transfer. So even though an object doesn't get much hot air from the manifold, it can get baked.
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FP Race manifold
- Thread starter cheekychimp
- Start date
jnava
Staff member
Recently purchased an FP manifold and Amber from FP said to get rid of the wrap that was on the manifold. She said that the wraps will help increase the likelihood of crack on the manifold. She also said that the best option is to use a blanket or modify the stock shield to cover it.
blacksheep
Well-known member
Would welding bungs on the manifold be easy to allow for bolts for a custom heatshield? It is cast, so I don't know how easy it would be? Also, would it hurt the integrity of the manifold?
4thStroke
Well-known member
brianawd went from a ported Mitsu manifold (can't remember which one) to a tubular DNP and noticed a big difference. Zach, who used to work at English dynod his FP and swapped it out for a tubular DNP, hoping it would make better numbers (this was on a 450awhp/500+awtq 16g DSM), the numbers were very close, enough to say that the changing condition attributed to the different numbers, it was within a few horsepower.
The FP holds heat very well, and thus sending hotter exhaust through the turbine which makes a big difference (another example of this is with retarded timing, the turbo spools faster). The tubular manifolds have longer and more equal length runners which work better for our application, but they dissipate heat too quickly and the gas cools off more so than the cast manifolds.
It ultimately ends up being a wash, but with the durability of the the cast manifold, it is enough reason to stick with a cast manifold until I'm ready for a T3 or T4 setup.
I have ~35k miles on my FP manifold and have not had a single issue with it. No rust, no cracks, although the discoloration is less than desirable.
The FP holds heat very well, and thus sending hotter exhaust through the turbine which makes a big difference (another example of this is with retarded timing, the turbo spools faster). The tubular manifolds have longer and more equal length runners which work better for our application, but they dissipate heat too quickly and the gas cools off more so than the cast manifolds.
It ultimately ends up being a wash, but with the durability of the the cast manifold, it is enough reason to stick with a cast manifold until I'm ready for a T3 or T4 setup.
I have ~35k miles on my FP manifold and have not had a single issue with it. No rust, no cracks, although the discoloration is less than desirable.
mitsuturbo
Well-known member
You "can" weld to it without hurting the manifold. I'd be more worried about the welds cracking though. I've seen some wastegate flanges welded to cast manifolds, and they've all shown cracks within a fairly short period of time.
I'd think a viable option for a heatshield would be something that uses the existing manifold to head studs. The two outer ones on the top should be able to hold a heat shield okay. I bought my coated FP GT30r bolt on turbine housing "used". For some reason, the PO had welded a little stud to the center of the forward facing part of the flange. It may have been for a turbo blanket, or some sort of heat shield. I don't really see that as a high expansion area, and a 3rd mounting point could be utilized there without substantial fear of cracking taking place on the weld. I'd think using those 3 mounting points, one should be able to come up with a halfway decent heat shield.
I'd think a viable option for a heatshield would be something that uses the existing manifold to head studs. The two outer ones on the top should be able to hold a heat shield okay. I bought my coated FP GT30r bolt on turbine housing "used". For some reason, the PO had welded a little stud to the center of the forward facing part of the flange. It may have been for a turbo blanket, or some sort of heat shield. I don't really see that as a high expansion area, and a 3rd mounting point could be utilized there without substantial fear of cracking taking place on the weld. I'd think using those 3 mounting points, one should be able to come up with a halfway decent heat shield.
prove_it
Well-known member
I've also played with the idea of using long manifold to turbo studs and using them to bolt down a heat shield. Seems like the simplest solution to me. Just haven't spent the time to figure out a source of good studs in the length needed.
blacksheep
Well-known member
Prove_It - I like your idea. 4 of them should easily keep the shield from moving. If we used long studs, we could use 2 sets of nuts - 1st set secures manifold to turbo and then put shield on and secure shield to the studs.
prove_it
Well-known member
Indeed, I'm never comfortable using standard studs though, I want some that can handle the heat. So I haven't found some, but i really haven't looked hard. If you make the shield out of 1/8" sheet metal it should hold up great and keep it's shape. Yea, my idea was to just use two nuts jammed together as the "perch" for the shield, that way it stays tight, only downside is that maybe over time the uppper most nut could seize and could loosen the stud rather than the nut.
Barnes
Well-known member
1/8" sheet is completely unnecessary from a radiative heat transfer perspective. I don't know if I'd even bother with anything over 1/32". Hell, a piece of aluminum foil would provide a large heat shielding benefit.
RedTwo
Well-known member
Now there's an idea... I shall watch what you do with this and copy it /ubbthreads/images/graemlins/laugh.gif
mitsuturbo
Well-known member
Quoting prove_it:
Indeed, I'm never comfortable using standard studs though, I want some that can handle the heat. So I haven't found some, but i really haven't looked hard. If you make the shield out of 1/8" sheet metal it should hold up great and keep it's shape. Yea, my idea was to just use two nuts jammed together as the "perch" for the shield, that way it stays tight, only downside is that maybe over time the uppper most nut could seize and could loosen the stud rather than the nut.
Maybe you should have a look at a tape measure, or a ruler.
I wouldnt really call 1/8 inch thick metal of any sort "sheet metal". More like "steel plate". I certainly don't think it would be suitable for ANY sort of "heat shield".
Indeed, I'm never comfortable using standard studs though, I want some that can handle the heat. So I haven't found some, but i really haven't looked hard. If you make the shield out of 1/8" sheet metal it should hold up great and keep it's shape. Yea, my idea was to just use two nuts jammed together as the "perch" for the shield, that way it stays tight, only downside is that maybe over time the uppper most nut could seize and could loosen the stud rather than the nut.
Maybe you should have a look at a tape measure, or a ruler.
I wouldnt really call 1/8 inch thick metal of any sort "sheet metal". More like "steel plate". I certainly don't think it would be suitable for ANY sort of "heat shield".
Sheet metal is expressed in gauge for thickness and an 1/8" in carbon steel would be between an 11 and 10 ga, which is pretty thick and overkill; in stainless it's 11 ga...more common sizes are say 14 ga (.075" in CS; .078" in SS) and the smarter thing to do is get something in higher gauge (#) of say 20 and sandwich some insulation between it, so it truly does not allow the heat to pass thru (within reason).
prove_it
Well-known member
I just threw a number out, settle down boys. Tossing ideas around. All I really know is that it will need to be thick enough to keep its shape with only the center of it being supported.
James
Well-known member
Can't it be built like so many we've seen before?
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^^^ if you catch my drift?
prove_it
Well-known member
I have no idea how it will need to be made. Cylinder #2 runner sits kinda high and the studs get too long then it will be difficult to tighten the manifold to housing. I only thought of an idea and haven't spent any time figuring out the details. It's one of a hundred projects I want to get done.
yeah, know too well how that goes, with too many things on the list!
I'm just going to coat mine, even though a custom heat shield would be nice as far as functionality goes...I made a shield for the more important areas though, like blocking off the PS pump and alternator area, + wrapped the O2, so hopefully that will help. If I had the money, I'd coat the turbine housing, or run a turbo blanket, but can't even seem to buy a damn 10 cent helicoil right now for it /ubbthreads/images/graemlins/frown.gif
I'm just going to coat mine, even though a custom heat shield would be nice as far as functionality goes...I made a shield for the more important areas though, like blocking off the PS pump and alternator area, + wrapped the O2, so hopefully that will help. If I had the money, I'd coat the turbine housing, or run a turbo blanket, but can't even seem to buy a damn 10 cent helicoil right now for it /ubbthreads/images/graemlins/frown.gif
