Tuning Fitting a PRV and boost guage.

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Tuning Fitting a PRV and boost guage.

craig20vturbo

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Anyone here run there 20v turbo with a PRV? Is it easy to fit?

How much work is required to fit a boost guage?
 
Hi Craig, PRV and boost gauge, two cheap, easy mods, and probably the most popular next to chipping. I'm not mechanically minded, but managed to fit both myself from asking questions on the fccuk forum. Anyway, I'll impart my wisdom... :)

Boost gauge - Gotta be the first mod on the coupe, or any turbocharged engine for that matter! Easy to fit, although finding a way for the hose through the bulkhead can be a pain. See the circle (1) for the correct location to tap into a boost hose:

enginepic.jpg


It's a "goal post" shaped hose, mine is Samco hosing as the original hose had a split. It should be black on your coupe. Just slice it in two with a sharp knife and add the T-Piece you get with your boost gauge. I then ran the hose through to the right hand side of the bonnet and then through the bulkhead, there's a way in that's used for wires etc. (See 2) You need to fit a boost gauge before the PRV, obviously!


PRV.jpg


PRV - Pressure relief valve, you probably know what one does, very simply it's usually a copper housing with nothing more than a ball bearing and spring inside, by turning the gnurled dial you can set boost, usually from base boost to about 1.3 bar although they do vary. Bypasses the ECU controlled EBV or electrical bleed valve, which has it's drawbacks as it removes certain safety features such as the limp home mode which cuts boost if the ECU detects a problem.
However the plus is instant boost! and a big advantage is no spiking or overboost which over time can temporarily wear your engine. Your coupe will feel faster but you have to be careful with your right foot, there's no boost limit in first and second like with the EBV and it's easy to spin 'em if you are not careful. You just have to adapt your driving style for the PRV and you won't look back. I tried my EBV again after running the PRV and the car just felt lethargic :D
Easy to fit, you just find the EBV which looks like a little dalek, it lurks by the front of the battery tray and will have a hose on the top of it and two pipes underneath. You'll need to remove the intercooler piping to get to it properly. See no. 3 in pic for rough location. You unplug the two pipes from the underneath of the EBV, they will have a red and blue bit of tape round them. You connect the red to the Right hand (straight) side of the PRV and the blue hose to the other (bent) side. I'm not 100% sure which is which TBH but I can find out easily if you need to know. After you have connected the two pipes to the PRV, block off the two holes in the EBV with a short piece of hose.
I then cable tied my PRV to the original EBV so it doesn't go walkies. Now take her for a spin and check what boost you are seeing with your swanky new Boost gauge. It's easy to adjust the boost by turning the bolt on the PRV one way or the other. When you have found the boost you are happy with, there is a securing thread on the PRV to make sure it stays in that position. I wouldn't recommend running more than 1.2 bar on the standard turbo and intercooler however. I run 1.2 and it's nice :p
PM Cosmograph on the FCCUK forum for the Armval PRV that 99% of the forumer's use, it's a quality PRV and I recommend it. I think they are £22 delivered or thereabouts.

http://www.fccuk.org/forum/showprofile.php?Cat=0&User=85&page=2&what=showmembers


I'd suggest getting the fueling checked out before upping the boost, if you are running a bit lean now, more boost may cause damage. Also I would fit a G-Tech chip at the same time as the PRV, this increases the fueling to cope with the extra boost. And it's the best £35 you'll ever spend :devil: looking at a good 20BHP increas with this mod. GrahamL is not yet on the new forum, but here's his ebay profile. Contact him, say Pinin prestatyn sent you and are looking at a G-Tech 1 I'm sure he'll sort you out.

http://feedback.ebay.co.uk/ws/eBayISAPI.dll?ViewFeedback&userid=traumax&iid=

Err I think that's it sorry if that's more information than you wanted :eek:
Well I hope I have been helpful. ;) :p
 
pinin__prestatyn Thanks very much for your post. I'll save it and then I think I'll get the parts over the next couple of months and do the work in the summer when it's a bit warmer and the tarmac is a bit stickier, will give me something to look forward to. :)

Cheers
Craig
 
What a post dude!!!!!!!!!!! One other thing i would mention is make sure its properlly secured, because if the wrong pipe comes off ur gonna hit infinate boost! :O

Ross
 
Yes as I found out once when taking mates to Llandudno, I have never felt such G-forces on the way there, It flew to the ton in about 12 secs flat. On the way home I looked at the boost gauge, I had been seeing 2 bar for at least 30 miles :eek: the blue part of the hose had come off the PRV.
still, the engine's not blown up thus far! (touches wood frantically)
 
Lol! Hopefully it was a nice cool day and ur fuel pump was on overtime!!

Ross
 
Just having a search in relation to bleed valves, pressure regulators and relief valves and I'm a little confused by this thread.

I'm going to have a go at tuning my TD Brava, and have been mooching round the net looking for info. I decided on using a pressure relief valve and a pressure regulator.

The pressure regulator (self relieving) to, well regulate how much pressure gets to the wastegate, a bleed valve would be a crude example.

The pressure relief valve, this prevents any airflow passing through it until the input pressure reaches a certain (adjustable) level.

For example, this valve can be set to 10 psi. Below this pressure the valve will be shut, above it the valve will open and allow air to flow through it. The control is of how much pressure it takes to open, not how much pressure it passes.

A PRV eliminates wastegate creep, it doesnt control maximum boost. Fitting one in the way described in this thread, would leave the wastegate actuater deciding the maximum amount of boost, which in the case of the Coupe would be less than standard

You see my confusion, I searched all the threads here with 'PRV' in them and see no dispute or contradiction. I'm guessing if I did the same on the fccuk forum it will be the same.

Now surely the collective members of two forums couldn't really be thinking they were running more boost, when they are in fact running less, especially with the aid of a boost guage. So is this actually a relief valve and regulater in one, or have I missunderstood something ?

Has anyone got a model number for it ? Maybe someone with a account at fccuk could have a search (must be registered).

While on the subject, does anyone know why/if it should be a self relieving valve. I see lots of statements saying it should be, but no explanation as to why. Surely the pressure will be either building towards your maximum boost or it will be at or over that point and will be relieved by the wastegate.
 
Alright, I've figured out the source of the confusion. The name 'pressure relief valve'.

I figure this PRV is what I would call a self relieving pressure regulator valve, but the name relief valve could possibly be applied to too.
 
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