So why is there no BOV on the SC motor??? Having always owned a turbo car and missing my old hks ssqv from my twincharged unit, I set out to see why roots style SC's have no bov... I've been told because there is no backpressure from a SC so there is no reason for one... they are used with prochargers.... belt driven... I just like the sound, reguardless of the need! haha... But once the air is in the "charge pipe", ie... SC horns and IC... that area is under load correct? One the SC stop's spinning, the air stops... but it does not stop instantaniously so there is still pressure in the lines yes? Who will justify with me that we need a M45 BOV

 

My understanding was that unlike a turbo, where it actually stops making boost and has to respool on shifts, a positive displacement blower still makes boost, thus it's better to recirculate it than blow it to atmosphere. I'm not very well versed on blow off valves, never been into them.

 

The simple explanation is that the blower comes after the throttle body, and that the blower is linked directly to the engine, because of those you dont get the sudden pressure spikes associated with rapid on off throttle application like you do in turbo cars, hence no need for a BOV.

There was a thread about this about a week ago, try and dig that up.

 

Well the bpv kinda works to this affect right?? Closes at full "spool" so to speak of the SC and is open to vent the air back to the intake...
This is mainly a boring Sat night and me looking for a reason to put a BOV on my M45 or if it would even work...

 

Oh yea? Hmm ill have to see what i can find... So there is no need for a BOV... but... would one werk??

 

You could fit a BOV in theory, but as they work on positive pressure it would only work when the bypass valve is closed (accelerating)

 

I don't know much about how they work or why to fit one. There are tons of people that have asked over the years though and there's lots of good info.

 

I'll just have to go back to twincharged to get one i suppose than...

 

Why did you abandon the TC to begin with? I know it roasted your piston, but being as how you'd just need new pistons and could then more reliably run TC, why did you not stay with it?

 

I had to sell the kit to help pay for some medical expenses as my dad has been bad this last year... wont go into detail but he has double knee replacements, diabetes and has had gangreen... having to cover work for him so he didnt loose it all cost us all quite a bit...

With the advances of the market now tho, i dont know what i should do, go back to TC, or a differnet route... full boost at 2200rpms was very nice tho!! 24lbs is crazy in a mini...

 

I know there is at least one person on NAM who runs a BOV on the M45, let me find the thread...

 

ok sweet!!
And put up a pic of those angel eyes... i wanna see!!!

 

Here you go:
https://www.northamericanmotoring.co...Blow+off+valve

Typing in "Blow off valve" into search also yielded about 2 pages of results.

I will send you pic or to of the Angel eyes in a PM.

 

Yea i noticed a few in there... sorry... its late and i was too lazy to search... haha...