silver86

iTrader: (10)

I just go the kit installed and have a question. While free reving in neutral the 4" 90 at the tb sucks in. I figure this might be normal since it isn't under boost yet but wanted to make sure. I dont know if I should find a stiffer hose or if its fine the way it is.

Thanks!

Orangemagic

iTrader: (2)

Pretty normal with a 90degree rubber elbow. Engine pulls vacuum right as the throttle body closes and sucks down the elbow.

torqen2k1

Possibly install a spiral spring on the inside of the elbow. Kinda like some of the radiator hoses have.

stevieturbo

post a picture, and just how much does it suck in ?

And what is your setup ?

There should never be ( a lot of ) vacuum between the throttle blade and atmosphere. If there is, there is quite a restriction somewhere.

You may see a tiny amount, but enough to collapse a hose sounds like far too much.

silver86

iTrader: (10)

It pretty much sucks in to about 1" of airflow.

My setup is a rear mount 76 turbo basically a modified STS kit. ported 241's and a 04z06 cam. At idel Iam pulling 19" of vaccum

The hose feel real flimsy too so I didn't know if I needed a thicker or stronger hose.

I will try to get a pic today or tomorrow. It collapses enough to cause a restriction while free reving. I know you shouldn't really free rev but it makes it to the point I can feel it and the car will barely hit 6500rpm with struggling.

stevieturbo

Rear mount probably explains it.

Use a decent 4/5ply silicone hose and it should be far less likely to happen, or switch to hardpipes where possible.

Or install a BOV reasonably local to the TB that will be partially open under vacuum and again it should never happen as this should offer the engine an air supply ( unfiltered...but hey ho )

Why do you want to rev the car to 6500rpm when sitting still ?

silver86

iTrader: (10)

Thanks for the info!

I do have a BOV pretty close to the tb. Once I finish this I want to get as many of the pipes welded rather than using the couplers.

As I said I know I shouldnt rev it while sitting still but I have reved it that high before the turbo and it seemed to get there rather quickly. When I was reving it I noticed it was struggling to rev past 5500rpm. Thats when a buddy told me that the couple was collapsing. So even though I know I shouldnt Im kind of glad i did if this is going ot be an issue.

stevieturbo

Not saying you shouldnt rev it, and yes you should be able to rev it...

But no sense making a habit of it just for kicks.

Just get a good quality hose on it, or even if you cut a short 3/" wide section of 4" pipe for example and slid this inside to re-enforce the hose, it should stop it.

Clamp the hard section from the outside to make sure it wont move.

dannyj661

hello I have a full silicon inner cooler set up on a suburban. I was told the kit is know for collapsing would that cause the system to not build boost and blow off like three separate times. Thats what my truck is doing. going from 3psi to 1psi boost and BOV hits like 3 different times.