So, the manifold arrived and I fitted it.
Sorry for lack of photos!
Manifold:
Looks like it's worth the £99 I paid. Little finishing to remove flashing where not necessary, which is fine.
No internal flow guides like the standard manifold. This worries me a bit. As you look into the exit of the oem unit. you can see it is profiled to
guide the gas into the turbo. With the Toyo one it is just a void, all cylinders feed into an unflowed volume.
Mating surfaces are milled flat, but finish is rougher than oem. On mine there were a couple of dinks at the edges during handling that I filed off before fitting. No biggie. Seems flat enough.
Internal volume is significantly larger than oem. Each pipe is quite a bit wider as it leaves the head. More on this below.
The mating flat that bolts to the turbo is significantly different to oem. It is much thicker which has some consequences.
1. The oem bolts aren't long enough. You'll need 3x M10 x 70 (rated 8.8 or higher, I used 10.9)
2. The bolt nearest the head MUST BE DROPPED INTO THE MANIFOLD BEFORE IT IS BOLTED TO THE HEAD. I didn't and had to unbolt the manifold to fit it (which was a total c**t).
By far the biggest (short term) issue with this manifold is that the increased pipe diameters has reduced the space around the mounting nuts on the top row to such an extent that NO STANDARD TOOLS ARE USABLE. Sockets wont go on, ring spanner wont go on and an open ender wont turn 60 degrees so it not usable. I had to modify a 12mm ring spanner - ground it's width to about 3mm and reduced the annular width around the ring as much as I dare (to about 2mm). Then bend the neck just above the ring to 45 degrees. Then leave off the normal washers. It's the only way. Even then the torque you can get onto the top row is questionable. I spent 2 hours bolting on just the manifold a few degrees at a time. Then had to undo it to fit the M10 turbo bolt!
USE NEW BOLTS AND GASKETS as you only want to do this once!
The turbo and exhaust lined up just fine one it was in place.
I've driven a few dozen miles today, most were slow (newborn in back), but it seems fine. Difficult to comment on performance as at the same time I fitted a refurbished turbo and a 3" Dp + decat. But the overall package is bloody quick for a stg1 LC tune. Part throttle is lovely and WOT likewise. Boost kicks in hard from 2.2k and showed no sign of giving up at 6k.
If this manifold lasts for 30k miles then it will be worth the saving. If it fails before that then I'll be back to report.
