Exhaust manifold, HKS vs Sound Performance

My HKS exhaust manifold arrived this morning. I thought I'd post this to detail the differences between it and my Sound Performance manifold, which is a copy of the HKS, and not a cheap copy either, it is well used in the US on big horsepower cars.

1st up the weight, the HKS manifold weighs 7.9kg without heatwrap. The SP weighs 7.2kg with heatwrap. I'm normally all for weight reduction but if the extra weight means it's stronger then I'm all for that in this case.

A pic to show the general shape. Although very similar in terms of T4 flange & wastegate positions are slightly different.

Looking from runner 1 you can see straight away the difference in pipework. Although hard to see on the head flange side, it's very easy to see on the T4 flange side, the HKS runners are perpendicular to the flange for a lot longer than the SP manifold.

One of the problems my SP manifold suffered was the T4 divider warped, when you look at where the runners join the flange it's easy to see why, the exhaust gases are directed at the divider, on the HKS by the time the gasses pass the divider they are running smoothly past it.

This photo may help clarify, you can see the runners from the right are pretty much directing their flow at the dividing piece.

Also the quaility of workmanship inside the manifold is superior on the HKS. I'm not saying the SP was poor, just the HKS is cleaner/smoother.

It's a little bit fuzzy but the SP manifold has rough bits where the runners join each other, the HKS is perfect.

Here is a shot from runner 6. Again you can see how far down the HKS runners sweep before they join the T4 flange, the SP runner 6 is nearly horizontal and it probably joins the flange at around 45deg angle.

A shot from the head flange.

The last differnce is the head flange itself. The SP is around 11mm thick, the HKS is 14mm. My SP manifold had to be cut at the flange as it warped. Maybe the extra materal on the HKS will make it that bit more resilliant.

So to sum up, this is proof to me that although a lot of the time HKS products may be seen to be more expenisve for no more gain than other products, in this case to me it seems to be a quality piece of kit worth the extra (esp if it saves me from going through another turbo )

Good writeup

That is interesting regarding the angle of the pipes going into the collector and the subsequent damage to the divider. Sounds all rather plausible.

I've dug up some pics of my BL manifold for further comparison. I don't know how wide the manifold flang is but it's pretty beefy, and the holes are slotted to allow for expansion, avoiding warping. The divider is incredibly thick compared to the others, so no danger of that letting go. I'd say the angle of the collector tubes are about halfway between the SP and the HKS ones.

Edit - and the interior welds are probably the roughest of the three manifolds, but they are rounded so shouldn't cause hotspots or cracking (and indeed, haven't yet)

-Ian

Poached for tech

Good writeup

 

That is interesting regarding the angle of the pipes going into the collector and the subsequent damage to the divider. Sounds all rather plausible.

 

I've dug up some pics of my BL manifold for further comparison. I don't know how wide the manifold flang is but it's pretty beefy, and the holes are slotted to allow for expansion, avoiding warping. The divider is incredibly thick compared to the others, so no danger of that letting go. I'd say the angle of the collector tubes are about halfway between the SP and the HKS ones.

 

Edit - and the interior welds are probably the roughest of the three manifolds, but they are rounded so shouldn't cause hotspots or cracking (and indeed, haven't yet)

 

-Ian

I try my best

Yeah, it's hard to show in pics, but when you see the manifold runner 6 is pointing straight at the point damage occured & where the divider warped.

That BL divider is chunkier than both of mine, I meaured the HKS one and it's thicker than the SP one, just say.

I know there are next to no stories of the SP manifold being poor quality & I'm not here to start one. Maybe it's just the setup of my car (it has destroyed 2 GT4088Rs ). Hopefully the new setup will go some way to making the car more reliable and stop it chewing up turbos & manifolds

PS the dawg said both manifolds are crap, it would rather have a bone

Wonder if Paul could put up some comparison pics and measurements from the Whifbitz manifold as well?

What does your dog think of the new manifold? He looks very interested.

how did you manage to ruin 2 gt4088s??? i know there prone to failure every once in a while but 2!!! lol

 

So to sum up, this is proof to me that although a lot of the time HKS products may be seen to be more expenisve for no more gain than other products, in this case to me it seems to be a quality piece of kit worth the extra (esp if it saves me from going through another turbo )

How true. I had a sp manifold and changed to the HKS with the new kit, the HKS quality and fitment was much nicer.

Nice write up Jay.

Is your dog wearing a nappy btw

What does your dog think of the new manifold? He looks very interested.

She thinks the welding is a little woof.

how did you manage to ruin 2 gt4088s??? i know there prone to failure every once in a while but 2!!! lol

Not sure yet, high egts maybe??

How true. I had a sp manifold and changed to the HKS with the new kit, the HKS quality and fitment was much nicer.

It sure is quality Ernie

Nice write up Jay.

Is your dog wearing a nappy btw

Cheers Kev, yeah she is, she's incontinent, vet says no point operating if she's not in any distress, we do that to stop her dribbling all over the place

BUMP

Upon putting my engine back together, Michel inspected my SP manifold - similar problems as with Jay's car, cracking in some runners and also the divider was warping - mine has been running a single for 3 years or so, maybe worth checking with if anyone else has a SP manifold before there's anything that goes boom!

Nice write up. I have had the HKS header on my car for over a few years now. No problems at all. The black heat treatment hasn't even faded yet.