har-vey

My tial is now on the car but i have just measured the weld on flange and the ID is 47.5mm

CynicG

Many thanks

chrispayze

For those who are interested, I've just carried out a little experiment whilst trying to quieten down my TTS kit. It has the Rotrex C38-81 charger runnin 12/13psi of boost (420ish BHP), so the air flowing should be similar to your HKS kits. I originally had the TTS-supplied 25mm Sytec BOV (vent to atmosphere), which gave a brief flutter when coming off the throttle at high revs (sound familiar?!). I swapped it out for a Turbosmart Dual Port 32mm for maximum flexibility.

The connection to the intake pipe is 25mm, connected by a short piece of hose, rather than the bolt-on flange on your kits. But I've fitted the 25mm adapter to the BOV to see if it was the BOV internals causing the restriction or the size of piping itself. I've also got a couple of sizes of output fitting to see it that was the restriction. My findings are interesting:

1. The 25mm intake connection does NOT cause enough of a restriction to cause flutter - with an adequate output port size, there is no flutter. All the findings listed here are with this size of input to the BOV.
2. With the normal 'trumpet' to vent to atmosphere, there is no flutter. Noise is as expected, a fairly loud 'shhhhh', but quieter than the 'tttsssssss' that the Sytec made.
3. With the standard recirc fitting (32mm I think - same as the standard intake fitting), there is no flutter, but vastly reduced noise (if whispered the word 'haw', that's the noise it makes, more quietly than the trumpet).
4. With a 25mm recirc fitting, there is flutter at the top end, but not as bad as the original Sytec.

Conclusion - the escaping gas needs to expand as quickly as possible, but can cope with remaining compressed for a little while (hence keeping the 25mm intake port is successful), but now that the internal BOV restriction is removed, the next greatest restriction is the output port size. This needs to be bigger than 25mm, and 32mm is ok. So, minimum BOV size (assuming the internal flow is equal to, or greater than, the output flow) is somewhere between 25 and 32mm. In short, buy a 32mm or bigger, but don't worry too much if your input connection is smaller. So the cheapest Turbosmart options are the 34mm kompact plumb-back (which you can run to atmosphere if you want) or the Vee-Port Pro (38mm input).

Hope that helps someone.

CynicG

Har-vey, any chance of some close ups of the BOV in situ. I'd like to see the clearance in that area and the recirculating connections. It all looks quite tight?

har-vey

ill try and get some pictures but the clearance isn't any closer than the inlet tube to the SC pulley. I would estimate around 15mm

har-vey

Hi all

Got the quote through today and each bracket is going to be around £60 based on the 4 interested. Is that something you would all be interested in?

Mods if this needs to be made into a GB let me know, i don't want to break any rules.

CynicG

That is a good price. I'm in.

Just to clarify, I know you guys went for Tial QR, Supercharger spring (2 psi) but what outlet? I've seen 1" and 1.37" but there was mention of 1.5"?

Did you fit a converting piece of hose to the 22mm HKS hose?

Bodyboarder1981

I'd be speaker to si @ Hendy ..... sure he would want to stock a few , might save some agro when he sells some more HKS kits !

Trunkz

Harvey stick me on the list for a bracket

Also - yes this would need to have its own separate thread in the for sale section. PM lovegroova or MB for guidance!

d1000rr

Ya I'm in for one at that price.