I'm gathering the last few pieces to put on my budget turbo kit. Since I'm running : 1.8 swap, mspnp2, wideband o2, and no afm, I ask a straight forward question of the opinion of those who have boosted before me.

Which style of blow off valve is the best bang for your buck? I am going in on a project that is mostly budget oriented, so any suggestions? Later on im thinking of a beautiful GFB bov but for now I need cheap function. Thanks a ton

 

I don't know what works best on a miata, but when I had my DSM I fell in love with the sound from a genuine greddy type-s.


Regardless of performance, I'd throw this on anything if I could keep hearing that sound lol. I checked those ebay replicas, but they don't sound the same, and any bov for 30 bucks is bound to not be as effective.

GFB or gofastbits makes some really awesome products, Blow off Valves/Diverter Valves

 

I'm trying to comprehend the question still

Not sure if clueless about bov's in general, or just ricer and by style you mean how it sounds

 

Forge motorsports makes a great oem 3/4" replacement if you can find it.




This might be a newer design, email forge and make sure it's the correct size.

http://www.forgemotorsport.com/Turbo...duct--756.html

$161 on Amazon -

 

he says msm then talks about a pieced together turbo kit

 

Yea I'm just going with 'msm' and provided a factory replacement link...

From previous posts claiming maaad HP on oem internals, vehicular intelligence is questionable



OP, fwiw... Greddy FV

 

Cheap, works, not ricer sounding.

 

I was curious which style works the best in your opinion. I have read that ssbov works best on air metered cars. Since I'm not metered and running a mspnp2, I'm looking for the most reliable style. Thanks

 

I guess I should of put in the title, " ihi rhf5 turbo " custom setup

 

In my own experience when using MAF, my greddy FV solved a lot of tuning headaches when I put it on my turbo system. (VS the old ebay copy greddy type rs that was on the car, had o-ring seals & a bad adjustment design.)

If using MAP, anything should be fine as long as your tuning is on point.


Are you using a MSM turbo setup?


Do you have a cat?

 

For vehicles running a MAF sensor, pretty much the only design rule is that you want a valve that can recirculate its exhaust back into the intake pipe downstream of the sensor. I can't imagine why any one specific make and model (eg: Blitz) would be superior in this regard.


Then just buy an OEM-style diaphragm valve. They will be more reliable, as a general rule, than piston-type valves, including the SSBOV you refer to earlier. Over time, the pistons tend to stick in their bores, which eventually leads to the valve hanging in a partially-open state.

The plastic-bodied Bosch valves are a good, reliable choice here. The one 90civichhb linked to on eBay appears to be an approximate copy of one, and is probably as good as any other in this regard.

On my '92, I used a cheap, Chinese made knockoff of a Greddy RS, for which recirculating adapters are available.

 

huh? I was just about to recommend the piston style cause IMO it is more reliable than a rubber balloon that will deteriorate over time and leak

also the bosch plastic valves are notorious for leaking, even at low boost.

We seem to have polar opposite opinions lol
(though all the piston style valves I've used were new or near new, so you might be right regarding super old ones with bad seals)

 

The one I linked is aluminum but is a replica of the Bosch unit for sure. I use that one on my car and it seems to be doing fine at 180kPa. I did, however, take it apart and used quality grease on the bits that rub stuff.

 

Yeah I've tried that one and it worked fine

 

I've had very good luck on a previous car (mk4 GTI) of using a stock evo diverter valve. I believe evo 8s and 9s both have the nice metal valve. If you Google "mad max diverter" it will show how you can modify them to hold up to ~30psi of boost as well.

 

Awesome input guys! That is the thought(typed) process I was hoping to evoke. I may jump on the non piston diaphragm to start with. I have my eye on a gfb but need to get it plumbed up and running beforehand. Save $ to get a proper tune.

 

This is approximately the valve that I settled on for my '92, after going through two others:

Black Turbo Type RS BOV Blow Off Valve Adjustable PSI Boost Accord Prelude RSX | eBay





I don't remember exactly who I bought it from, and I have no idea how many different places are actually manufacturing these knockoffs (relative to the number of vendors selling them under different names), but it gave me years of reliable service.

The recirc adapter is a separate piece. I cut my own on the lathe, but you can also buy them for about $15.


A lot of these have dual, coaxial springs inside. For lower-boost applications, or for a softer transition into and out of venting, you can open it up and remove the smaller of the two.

Regardless, you'll want to open it up anyway to clean it out thoroughly (this sort of Chinese **** is notorious for coming out of the box full of machining chips and abrasive dust) and put some light grease on the moving parts.



Tubes are also widely available with a mating flange for it pre-attached, in case you're not up for welding. Example: 2 5"T 6061 Aluminum for Greddy Turbo Intercooler Blow Off Valve Flange Pipe Tube | eBay

 

Thanks joe!!! Good call on the initial go thru. I'll pretend it's a "new" 91/30 and clean the nasty stuff out of it.