bov ?

[Shawn C]

TYPE H
Hey, I have a turboxs bov, I was just wondering where u put the line that comes off the top of the bov to the engine? I heard it was suppose to be hooked back to the intake but I do not know where.

[duplox]

The BOV itself goes on the intake pipe before the throttle body, the line off the top goes to the intake pipe/intake manifold after the throttle body. if the BOV senses a pressure difference before and after the throttle body(quickly closed throttle on boost results in vacuum after throttle body, boost before) it will open and vent the extra boost. BOVs arent really neccesary for fuel injected cars, imho... the only reason i've ever heard to run them on a fuel injected car would be to prevent pressure waves from bouncing off the throttle blades and reflecting back and somehow damaging the turbo, but I've never seen a turbo damaged as a result of not running a BOV. However, on a blow thru carbureated car, the massive pressure difference before and after the throttle blades would cause a massive surge of fuel into the engine, stalling and vapor locking it. (fuel bowls are pressurized by residual boost, emulsion tubes are subject to vacuum from below the throttle blades... result is lots of fuel!). I know lots of you like the sound of BOVs, but I personally don't like to advertise what I have under the hood. After all, I need someone to race! If I could avoid running a BOV I would.

Speaking of which, does anyone know where I could get a quiet BOV? All the aftermarket ones i've seen seem to brag about how loud they are... If no one does, I'll just run a pair of stock ones vented to the turbo's inlets.

[Polygon]

Like you said Duplox, Blow Off Valves and Diverter Valves are to prevent backpressure when the throttle plate closes. This can be damaging to the turbo bearing or even the blades. Ball-bearing turbos can usually handle this but sleeve-bearing turbos can easily be destroyed by this backpressure. I would run one no matter what. If you don't like that noisy ones Duplox, give a diverter valve a try. Instead of venting the air they divert it back through the intake. They are very quiet unless you have an open filter element, and even at that they aren't very loud. A good one to get is the stock DV off a first generation DSM. They can hold a lot of boost and are very cheap.

[duplox]

Learn somethin new every day. I think that perhaps for very high boost applications(20+) backpressure would be a significant problem, but I've seen many more cars without BOVs than with them... If it really was that damaging to the turbo then everyone would have one. Perhaps it'll shave some mileage off the turbos life, but I personally dont think one is neccesary for a EFI engine. After all, for the $100+ it costs for one of em, you could have your turbo rebuilt! If a turbo without a BOV lasts 30,000miles and a turbo with a BOV lasts 35,000, I'll save my 100 bucks and get 60,000 miles out of the same money. I'm not recommending anyone follow my advice, I could very well be wrong, but thats just what I'm gonna do.

Another thing... In Corky Bell's book Maximum Boost, he doesn't mention BOVs(he refers to them as anti-surge valves) when discussing EFI, only talking about them in reference to blow through carbureated designs... I don't think Corky would have left out something that is that detrimental to the turbo.

[Polygon]

Yeah, it is really only necessary for people with sleeve bearing turbos. Also the first gen DSM diverter valve can be bought for around $35.

[duplox]

Is there some website that sells them? I'm interested.

[DeleriousZ]

going for the ultimate sleeper car duplox?

[duplox]

hehe yep... two turbos hidden inside the firewall along with the air-cold water intercooler, stock air cleaner assembly that has the nice stock pickup tube, with the boost line hidden inside... never know what hit em. shootin for 500hp at the rear wheels.

Although it can't really be that much of a sleeper... 69 mustang with a roll bar and 12" wide slicks on the back. But I dont think anyone will suspect a 10 second 1/4.. hehe

(old picture... rollbar and slicks are missing!)

[DeleriousZ]

h0t damn dude!!! is that thing street legal??

[tran_nsx]

sweet car duplox, i was considering of getting a 72 mach 1 for a while but decided not too due to my unfamiliar territory in v-8's, its issue of gas guzzling, and highly worried about reliability.

[Hypsi87]

Originally Posted by Polygon

Yeah, it is really only necessary for people with sleeve bearing turbos. Also the first gen DSM diverter valve can be bought for around $35.

The bigshaft sleve bearing turbochargers can handle it to. Have you seen the bearings in a bigshaft turbo? They are absouly massive!!!

[Polygon]

Originally Posted by duplox

Is there some website that sells them? I'm interested.

You could do a search on google. Most people just buy them at junk yards or on eBay. If you buy from someone online try to find a modified one. They can hold over 30 PSI if modded correctly.

Originally Posted by Hypsi87

The bigshaft sleve bearing turbochargers can handle it to. Have you seen the bearings in a bigshaft turbo? They are absouly massive!!!

Hmm, never seen them. Then again I only really pay attention to the BB turbos.

[duplox]

yeah its street legal. Any car over 25yrs old in my state doesnt have to pass emissions, and inspection isn't anything difficult to pass. Right now my state(CT) is redoing the entire DMV. All I had to do to get it registered is bring it to the DMV and get the VIN verified.

Yeah gas mileage sucks, but thats what you pay for speed. It weighs around 2850lbs, I'm guessing with the turbos and intercooler it should weigh at most 3000lbs. With me in it brings it to 3150lbs, usin this calculator: http://www.rpmoutlet.com/dyno.htm it estimates a 10.75 1/4 mile. My goal when I got the car is under 11, so 10.75 will do.

[DeleriousZ]

wow man.. that kicks ass!! but how's the traction on those slicks?

[duplox]

the tires in that picture suck, I was bleeding my brakes when the rear master cylinder blew so I had no rear brakes... When I tried to put it in the garage, if I stepped on the brakes while it was idling, the rear tires would just spin. Now thats low end torque