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diesel turbo questions

Posted: Wed Dec 13, 2006 6:54 pm
by bigbennymq
hi this may seem like a stupid question but i dont know anything about it i will have a turbo sd33 and i wanted to know can u put a blow off valve, wastegate on a diesel and if ya can how do u so
thanks

Posted: Wed Dec 13, 2006 8:01 pm
by MQSWBUTE
why would you need a bov on a diesel

Posted: Wed Dec 13, 2006 8:18 pm
by bigbennymq
well i dont know much about this shit man isint it just like ya petrol engine owhy shouldnt ya put one on

Posted: Wed Dec 13, 2006 8:25 pm
by killer_garden_gnome
i dont know about yours but i owned a non turbo mk and the basis of a blow off valve is to release excess pressure while releasing the throttle and unlike most diesels my mk had a throttle body and the pump ran on a vacuum in the manifold, since yours is boosted i cant see how your pump would run on vacuum but if it does have a throttle theoretically u should be able to put one on it, dont worry i know plenty of ppl that want BOVs on diesels

Posted: Wed Dec 13, 2006 8:28 pm
by bigbennymq
yeh because people hav said ya cant but then some have said ya can...do ya know if ya can fit a wastegate to a diesel aswell

Posted: Wed Dec 13, 2006 8:37 pm
by badger
if you have a throttle body on your inlet you can run a bov.
mates mq has throttle body and is a non turbo with a schweitzer turbo on it
could run a bov but the giant truck noise as u push the clutch in is way cooler and bov doesnt surve a huge purpose like a petrol

Posted: Wed Dec 13, 2006 8:57 pm
by MQSWBUTE
bov are useless on diesels theres no reason why you wouldwant to look the inlet manifold pressure

its all noise bov waste of time and money unless you got a petrol turbo thats plumbed back

Posted: Wed Dec 13, 2006 9:26 pm
by txhog
mmmmmmm, BOV, the SAAB boosts to about 30PSi so they may make it more possible. Dunno

Want one on my ute :cool:

This Videos about 2 minutes long, towards end you will see gas escape though bonnet ejectors.

http://www.youtube.com/watch?v=hf_Pf77Y9Ws

Posted: Thu Dec 14, 2006 6:26 pm
by bigbennymq
u reckon u could find out of ya mate how to fit one or some sort of diagram off him

Posted: Thu Dec 14, 2006 10:36 pm
by bogged
MQSWBUTE wrote:why you would want to look the inlet manifold pressure
fooly sik...

Re: diesel turbo questions

Posted: Fri Dec 15, 2006 9:24 am
by tweak'e
bigbennymq wrote:hi this may seem like a stupid question but i dont know anything about it i will have a turbo sd33 and i wanted to know can u put a blow off valve, wastegate on a diesel and if ya can how do u so
thanks
wastegate? if its a turbo its allready got one!

you can fit BOV and they work well IF it your motor has a butterfly in the intake.

a BOV they can work if fitted on non-butterfly sytems but they only pop off very rarly so its pointless for most people. kinda like fitting a BOV to an auto.

Posted: Fri Dec 15, 2006 9:03 pm
by bigbennymq
u know how to fit one?

Posted: Sun Dec 17, 2006 7:27 am
by king55
Why would you still want to fit one when everone has just told you it's useless doing so. Let me guess it's all about the noise (wank factor) right. you would be just wasting your money.

Posted: Sun Dec 17, 2006 9:55 am
by bigbennymq
They do help but not as much as a petrol but when it was for free and i got nothing to do why not fit it ,wtf with wank factor king 55(by the way great name lol :roll: ) and u are pretty much callin anyone wit a bov on there truck a wanker and plenty of diesels hav bovs , wouldnt hav a clue how to fit one thats why i was askin for guys help and opinons and who cares if i fit it i dont give a shit what (king 55) thinks i dont even know u so dont insult people u dont know or never met

Posted: Sun Dec 17, 2006 10:04 am
by txhog
Fit one it will be cool, I just dont know how to do it, if you find out post the details :twisted:

Posted: Sun Dec 17, 2006 11:51 am
by bigbennymq
once i muck around wit it and get it right i'll send ya all the info

Posted: Sun Dec 17, 2006 12:54 pm
by king55
all everyones trying to say is that it's pointless putting it on a diesel so why would you want to waste your time trying to put it on there if it does nothing in the first place.

Posted: Sun Dec 17, 2006 1:05 pm
by bigbennymq
ok

Posted: Sun Dec 17, 2006 1:35 pm
by tweak'e
king55 wrote:all everyones trying to say is that it's pointless putting it on a diesel so why would you want to waste your time trying to put it on there if it does nothing in the first place.
not quite. SOME deisels respond very well to BOV's. however most of them you simply disable the things that cause the problem rather than fitting a bov.

some people have electronicly triggered BOV's which has helped but normal 4x4 driving style they don't do much. you realy have to be driving it hard to make use of a BOV on a deisel.

concidering how much hassle it is welding pipes etc on i wouldn't bother.

Posted: Sun Dec 17, 2006 2:33 pm
by bigbennymq
well they have a releif valve on the throttle bbody could u replace that wit an aftermarket releif valve or a new bov

Posted: Sun Dec 17, 2006 2:39 pm
by tweak'e
if the releif vavle is on the turbo side of any butterflys then you could replace the releif valve with a bov.

Posted: Sun Dec 17, 2006 3:04 pm
by bogged
bigbennymq wrote:plenty of diesels hav bovs
yea? where...

Posted: Sun Dec 17, 2006 3:28 pm
by tweak'e
a good example is http://www.hiluxsurf.net/index1.htm

cheers to dandownunder

Posted: Sun Dec 17, 2006 5:22 pm
by bogged

Posted: Sun Dec 17, 2006 5:43 pm
by shakes
many people have said dont bother with blow off valves on diesels but EVERYONE is yet to explain why?

from what i understand they prevent turbo shudder caused by the throttle closing. I know squat about diesels too, so could quite easily be missing something.

if ya gunna hassle the bloke about it only being wank factor, at least explain yourselfs as to why!!

Simon

Posted: Sun Dec 17, 2006 6:32 pm
by bigbennymq
your spot on mate

Posted: Sun Dec 17, 2006 6:34 pm
by bigbennymq
one more thing where does the rubber line off the top of the bov go to on a deisel where do i put it lol i will say again dont know much

Posted: Sun Dec 17, 2006 7:31 pm
by tweak'e
shakes wrote:many people have said don't bother with blow off valves on diesels but EVERYONE is yet to explain why?

from what i understand they prevent turbo shudder caused by the throttle closing. I know squat about diesels too, so could quite easily be missing something.

Simon
on a petrol when you back off the throttle eg when changing gears, the sudden closing of the throttle butterfly causes a pressure wave to bounce back to the turbo which can cause it to slow down or even stall.

also by letting off pressure it takes some of the load of the turbo allowing to continue spinning at high rpm.

now a good diesel doesn't have a throttle butterfly so there is no pressure wave bouncing back so no need for a bov. however a lot of diesels have butterfly's that partially close at low throttle positions. this for emission purposes eg it helps suck in more EGR to reduce emissions. because EGR causes performance/economy loss and often goes faulty, the emission system is often disabled ie butterfly is disable therefor no need for a bov.

you can still get some gain with a bov, simply because it drops the load off the turbo during gear changes helping the turbo keep spinning at high speed. probably not that big a deal on standard boost vehicles.
where does the rubber line off the top of the bov go to on a diesel
if your motor has a butterfly AND you get vacuum then you can simply connect it to the inlet manifold, the motor side of the butterfly.

if you don't have a butterfly you need to use the vacuum system to run it and use a solenoid connected to a throttle or clutch switch. i lot of mucking around but i hear it works very well and has very fast response.

Posted: Sun Dec 17, 2006 7:39 pm
by bigbennymq
sorry to be a shit do u know if mq patrols hav butterflys and where on the throttle body do ya connect it or how does it connect to manifold

Posted: Sun Dec 17, 2006 7:47 pm
by tweak'e
i have no idea what those motors have. you will need to work it out before hand. it would be a good idea to get familar with the motor and what everything does on it before doing ANY mods.