check valve behind ISCV.

[supraguru05]

I am building a turbo engine for a friend and the check valve is missing out of the turbo manifold I have. most likely I took it a long time ago for the race car. My question is how important is this check valve for a engine that is just going to be on stock boost. I assume its there to prevent backflow through the idle valve under boost when it could be forced open. I can get one from someone on here but I was hoping to get the rings broken in this weekend so if its not entirely necessary then i would like to know.

thanks below is a link to the part its right behind the valve and IIRC is orange

http://www.cygnusx1.net/Supra/Library/EPC/291410/catalog.aspx?F=2211&P=2

its 25748 in that picture. also if anyone has one laying around I would love to get it from you.

 

[lowtaco]

I know its a need to have part, as far as running goes I dont think it will idle correctly without it, plus you would have a massive boost leak.

 

[mkIIIman089]

I think the massive boost leak would be your primary problem, as its just going to flow right back out into the intake pipe.

 

[Enraged]

if you run a maft pro on speed density, it's not required

 

[mkIIIman089]

Well, yes, it is...

 

[supraguru05]

alright that answers that. i didnt know if it was a backup or if the isc valve spring was that weak. ill have to find one then thanks

 

[Zumtizzle]

if you run a maft pro on speed density, it's not required

It's needed even more. :nono:

 

[dbsupra90]

kyle-

what management are you running? btw, i looked and don't have one.

 

[supraguru05]

kyle-

what management are you running? btw, i looked and don't have one.

friends car its just stock.

if your talking about my car its also stock with a safc

 

[jetjock]

i didnt know if it was a backup or if the isc valve spring was that weak.

Just FYI: First, there is no spring in the ISCV and even with the check valve missing it's position can't be changed by airflow. Second, stock boost can be achieved with the check valve missing. It's no different than running with a blown stock bypass valve, which has more conductance than the ISCV. Not that I recommend doing either...

 

[Enraged]

It's needed even more. :nono:

there are several people running without it. you have to adjust the idle, but it's not a big deal.

 

[Poodles]

Running without the ISCV entirely, not missing the valve...

If you're missing the valve and you're running a little filter instead of back into the intake you'll have a bad boost leak...

 

[Enraged]

Running without the ISCV entirely, not missing the valve...

That's what I meant.

 

[jdub]

That's what I meant.

Perhaps you should take the time to read the question...this thread is about the check valve under the ISCV, not about removing it.

Removing the ISCV disables all of the ECU idle-up functions...it's not a good idea when running the stock TCCS.

 

[Enraged]

misread it, whatever.

 

[ForcedTorque]

I've got a couple of them laying around. I'll PM you, as this is not a sale section.