advise needed
Turbo Mini Forums

is this the correct way to go for a blow trough setup? (see image) and what position is best for the blow off valve? number 1 in front of the inter-cooler so no pressure builds up in there or number 2 on the plenum chamber so pressure drops as fast as possible in front of carb.

(hope the image comes with the post)

Edited by Rammie2000 on 30th Dec, 2012.

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

I would put the blow off valve at the plenum rather then pre-intercooler.

Plenum all the time

Owkey. So for the rest everything looks ok?
Not sure how it all works yet ( meaning the bypass valve and actuator thing who opens it) but getting the idea in the brain slowly but surly...

What is the best gasket to use on a blower engine? I seen that there are metal head gaskets build up by thin plates riveted together.

Also how much work is it to adapt a standard 1275 electronic ( Lucas) ignition ( dizzy in English?) for the use on such a engine? Or isn't it worth the money? ( have one laying on the shelf)

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

Hallo Rammie,
BK450 (or 470?)for headgasket is most popular choice here.

I would strongly suggest using Megajolt for the ignition; it's a bit of investment but will pay out in the end; have a search.

Dazed and Confused....

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

Location of the BOV is not important...however, I absolutely would not mount it close to a carburettor where there is a risk fuel may get expelled from it.

The plenum is a bad idea IMO.

What type of blower is it, that you're adding some sort of boost limiting device ?

With suitable control, a BOV can be used to perform both functions ( and a suitable BOV of course )
Also, a SC BOV will ideally be open at idle. Even more reason not to have it mounted on the plenum.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

The nature of the blower you are using, when geared correctly it will offer pretty much maximum boost immediately, and throughout the rpm range, up until it cannot supply anymore air.

So I think all you need to do, is sort the gearing correctly.

There are various pop off valves to vent boost above a certain pressure, but they are a bit crude, and really only intended as a safety, or regulatory thing.

If you can find a valve ( some people use a turbo wastegate ) etc where you can gain access to the lower port to blow it open, that will allow you more control as to when the valve opens.

I think you'd be better trying to get the gearing right, and forgetting about trying to dump boost altogether though.

Although my car isnt a Mini, I do vent boost in the lower gears to try and maintain some sort of traction. I use my BOV and a 4 port solenoid so I can either blow it shut, or open as required and use my ecu to control it.

It would be harder to achieve the same level of control though mechanically, other than a simple setup like you had suggested. Ive been searching for links to sellers of specific pop off valves to do what you want, but cant seem to find them. They are readily available though, and would be better calibrated to do what you want.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will