is a bov on a vnt a worth while mod?

[89CSX#17]

I am considdering installing a BOV on my CSX mostly for making it easier on the turbo. I was wondering if this is even needed simply because of the design of the VNT's with their vanes instead of the wastegate.

[DirectConnection]

Yes. It is a worth while job. You want to vent the compressor spikes no matter what turbo you are using. Given the high shaft speeds of the VNT, it is very important I think. All '90 VNTcars came equiped with the BOV in the airbox. Any '90 T-I car will have the exact same airbox/bov setup as the VNT. Only thing is getting the lower piping to vent to the bov.

[crazyace]

The other reason that a BOV is extremely important on our cars is due to the very small shaft size in the VNT turbo. Unfortunately it is much smaller than the one used in the T3 turbos. Therefore that BOV can help eliminate the twisting motion the shaft goes through when the throttle slams shut. Chris at TurbosUnleashed has a very good photo of the two turbo shafts side by side and it is frightening to see how much of a difference there really is.

[DirectConnection]

I just got my VNT back on the road after a 3 year hiatus. You just scared me about the small shaft issue. Maybe it'll run the stock boost for now

[crazyace]

I got to digging in PC last night after posting that. I found the pic he sent me. The difference is quite noticeable, if anyone wants a copy of it just let me know.

[89CSX#17]

Thanks for the info guys, I am planning to install it in the lower hose before the intercooler. It looks like the easiest way to install it. Let me know if this good or bad. My buddy has a bunch of cut hoses and piping that I am going to try. I don't want to cut my good stock hose.

[Shelby VNT]

I found it easier to install my BOV on the upper intercooler hose. I just yanked the stock air box and used a hard pipe in it's place. The lower hose / combination pipe is located over the top of the tranny and it's pretty tight. It's also not straight enough to actually weld on a BOV flange as easy.

[crazyace]

It is just as easy to install on the lower pipe.

[Shelby VNT]

Not really! It doesn't get much easier then a hard pipe in place of the stock air box. The lower intercooler connection is partly hard pipe and partly hose. The hard pipe has some bends in it to wrap around the tranny. Take into consideration your turbo intake hose is also running over the top of the lower IC hose. Clearance can get tight.

[crazyace]

You can get as exclamation mark happy as you wish, but anyone with a little welding ability and thought can easily install a BOV in the lower tube. Besides that, if you are going to the trouble of installing a different BOV 9 times out of 10 you are making a custom intake tube. After that you now have plenty of extra space.

[sleeping8t7]

I preffer on the bottom hose. First, if I remove the airbox, then I don't get any air flow through the computer. Where I live, (I use mine as a daily driver) there is alot of traffic and I need air going in there. Second, if I do remove the airbox, the left over boost pressure has to pass through the intercooler before going out the BOV. It would make more sense to do that so the air gets out right away.

[crazyace]

Sleeping8t7,
It has been proven many times over that Chrysler running the air intake through the computer is plain and simple over kill. I know quite a few people running their vehicles where temps regularly go above 90-100 degrees and they have been for years now, with no troubles. But, anyway we look at it the whole thing will just boil down to preference of the owner. Do what floats the boat.

[Douglas Dircks]

I've got a Talon BOV on the CSX. Compared to the GLHS the car is slow which could be due to the fact the CSX has tiny exhaust which somebody must have put on the car at some point.

[Dan Culkin]

Don't forget, if you're only running stock or near stock boost, a stock BOV from another turbo dodge works perfectly. If you take one off of an 88up T1, along with the insert into the rubber hose, you can put it in the little hose between the airbox and the throttle body. This way you don't have to remove the stock airbox, or hack up one of the intercooler hoses.

[IllusionalTA]

VNT's have BOV"s STock.. at least my 90 Does..