Blow of valve

Post by **muddies** » Thu Mar 10, 2005 3:54 pm

HOW do blow of valves work and would they work on a turbo td4.2 with 3" exhaust and snorkel? Would their be any performance gains?

Post by **Dee** » Thu Mar 10, 2005 4:48 pm

when you are accelerating your turbo is pushing air into your cylinders, when you take your foot off (to change gear etc) your turbo is still spinning there fore pushing air, and if it has no where to go it puts strain back on to your turbo and slows down its spin, there for having to spool up again once u are in the next gear accelerating again, what the blow off valve does is vents that air that has nowhere to go either into your exhaust pipe or out into the open air under the bonnet, preventing your turbo slowing down to much between acceleration.

Somehting to that effect i think. however there will be much bigger petrol heads on here who will have a much better understanding of it than I.

As for diesel engines... i wouldnt know where to start in reference to power gains...

Post by **Brendan-s** » Thu Mar 10, 2005 4:55 pm

furthering what DEEV8 said, it allows the turbo to stay spooled up for longer so you're on boost consequently longer, hence more power and a flatter torque curve (dont have turbo lag with each gear)

Post by **muddies** » Thu Mar 10, 2005 5:11 pm

IF the car was under water would the blow off valve suckwater in it or would it close quick enough to stop water from getting in?

Post by **big bundy** » Thu Mar 10, 2005 6:19 pm

shouldn't be changing gears in water crossings :finger:

Post by **bazzle** » Thu Mar 10, 2005 7:12 pm

Wont work as no throttle plate to stop airflow req a BOV. See post in General Tech

http://www.outerlimits4x4.com/PHP_Modul ... blow+valve

This Forum is turning into a Ricer forum

Bazzle

Fri Mar 11, 2005 11:36 pm

After reading that link.. I have a little Question now. I have a 1986 Mk SD33T.. Needless to say some power might be nice.. Currently running 2.5" exhaust no mufflers... Whats all this turbo boost/Fuel adjusting thing.. Is it possible to dig some ponies out of this beast?? Its still a big heavy thing.... But can a few Hp be found ??????

Post by **morkz** » Sat Mar 12, 2005 8:45 am

Team Carpet RC Vehicles wrote:After reading that link.. I have a little Question now. I have a 1986 Mk SD33T.. Needless to say some power might be nice.. Currently running 2.5" exhaust no mufflers... Whats all this turbo boost/Fuel adjusting thing.. Is it possible to dig some ponies out of this beast?? Its still a big heavy thing.... But can a few Hp be found ??????

your best bet is either to take it someone who's a diesel tuner or you could try do it yourself.

1. you'll need a pyro and a boost guage.
2. Not sure how much boost you can get upto with these motors but if you put the boost to about 10-12psi.
3.next you'll have to add fuel to compensate. (as many people will say boost alone wont give you more power.. fuel is required)
4.you'll need to check exhaust temps if the temp is over 550-600c you'll need to back the fuel off.

im pretty sure thats just the jist of it all..

for about $200-$300 i'd just take it to diesel tech and get it tuned on a dyno.

also you may wish to check your injectors as well they could be dirty.

Post by **coxy321** » Mon Mar 14, 2005 8:36 pm

Also (depending on your budget), if you're after power an intercooler might be worth looking at. They will cool the charge of hot air (cause its been compressed by the turbo-and gets hot), therefore making the air entering your motor cooler, and more dense.

Denser air means more oxygen particles, which in turn equals a cooler running engine, with more power and torque. I think the heat reduction figure is around 30% average. They can also increase engine life and fuel economy, provided you dont go too over the top on the search for ponies.

Coxy

Post by **adam.s** » Mon Mar 14, 2005 9:11 pm

just dont bother buying one of those cheap hybrid fmic's.

waste of time.

the standard cooler off a soarer/supra is worth about $50 and good application for you guys.

is like 280x280x100mm, easy to fit somewhere and good enough size to do the job.

Mon Mar 14, 2005 11:15 pm

so let me see.. If I buy a "intercooler" that comes off a supre or soarer I can bolt this thing on my Mk patrol and get more power :lol:

...... Gee wizz talk about thinking outside the square. No wonder I come here you guys are full of surprises.. :armsup:

Tell me more what do I need and how much.. This is getting interesting

Post by **coxy321** » Wed Mar 16, 2005 11:29 am

Yeah, go and have a search on ebay. What do you think happens to all of the old intercoolers that get taken off when the racer boys upgrade? The workshops sell them to make a bit of extra cash on the side.

I've seen plenty go for anywhere between $30 and $80, all of which would do the job on our cars easy. Its just a case of buying one of those intercooler piping kits to hook it all up.

I'm yet to decide on front or top mount. Probly top mount, and i'll buy a second bonnet to cut a hole in it and throw a small scoop on it too.

Cheers - Coxy

Post by **GUJohnno** » Wed Mar 16, 2005 11:46 am

coxy321 wrote:Also (depending on your budget), if you're after power an intercooler might be worth looking at. They will cool the charge of hot air (cause its been compressed by the turbo-and gets hot), therefore making the air entering your motor cooler, and more dense.

Denser air means more oxygen particles, which in turn equals a cooler running engine, with more power and torque. I think the heat reduction figure is around 30% average. They can also increase engine life and fuel economy, provided you dont go too over the top on the search for ponies.

Coxy

I've been thinking about this. I understand about the cooler air being more denser but aren't you still getting the same amount of air from the turbo? I can see the benifits of having cooler air and therefore less strain on the motor but I can't see that you'll have more air.

Post by **Dee** » Wed Mar 16, 2005 12:24 pm

not "more air" but more oxygen particles, which, along with fuel of course makes makes it go *bang* better on each igniting stroke.

Post by **GUJohnno** » Wed Mar 16, 2005 12:40 pm

humm.........

Post by **Dee** » Wed Mar 16, 2005 12:58 pm

year 12 science mate :roll:

Post by **coxy321** » Wed Mar 16, 2005 3:49 pm

I'll try and make it as simple as possible for you:

Hypothetically, just for the sake of explaining this:-

Say 1 cup of oxygen at 90 degrees (eg. turbo charged) contained 1,000 molecules of oxygen

and, 1 cup of oxygen at 60 degrees (eg. intercooled turbo) contained 1,500 molecules of oxygen

and, 1 cup of oxygen at 30 degrees (eg. intake of N/A motor) contained 3,000 molecules of oxygen.

Basically, there's more of the good stuff, except packed into the same amount of space. You know the theory that things expand with heat?? Well so does oxygen particles, and they also shrink when they get cooler.

Because the oxygen is what makes the fuel burn in the cylinder, the more oxygen particles that are squeezed into the cylinder, the bigger the burning effect, which in turn pushes the piston back down harder and faster. Thus creating more power.

If you're after more info on how it all works, visit HowStuffWorks.com

Cheers - Coxy

Class Dismissed!!!

Post by **Dee** » Wed Mar 16, 2005 4:01 pm

ahhh...

Mr. Coxy, what you've just said is one of the most insanely idiotic things I've ever heard. At no point in your rambling, incoherent response was there anything that could even be considered a rational thought. Everyone in this room is now dumber for having listened to it. I award you no points, and may God have mercy on your soul!

juuust kidding. thanks for the laymans terms mate... took the words right outa my mouth

Wed Mar 16, 2005 11:01 pm

Ok... I've been watching this topic for a few days now and I have decide it will be an intercooler for me.... I'm going to try hunt down a Supre intercooler.. and a Bonnet scoop... Can anyone help with places to look/call (other than ebay) or maybe hook me up with some parts... Mk with a bonnet scoop :lol:

This is gunna be FULLY SICK !!! :armsup:

Any comment, suggestions or tips please let me know. I'll also keep posted on progress for people in the future who read thios post with the same ides :cool:

Thu Mar 17, 2005 12:42 am

Ok making headway already.. Found an intercooler on ebay for a R33 skyline.. Will this do?
I have email guy to get some pics.. None on his ebay auction

Am I going about this right.. Please advise.. SHould I buy these things???

Post by **muddies** » Thu Mar 17, 2005 5:03 pm

The red bonnet scoops are for vl brocks and should only be used on such.

dont become a spare part wannabe.

Post by **coxy321** » Thu Mar 17, 2005 5:22 pm

I was thinking of something more along the line of maybe a Bitsashitti Triton scoop, or a Rodeo scoop...??? Something a little more modest, that wont be a magnet for leaves, mud and small animals to get caught in. You dont want it getting all chocked up either, other wise it is useless.

It might be worth going to a wreckers for a look. It's not very often that you get written off 4x4's that have had the scoop wrecked. Most scoops are a removable section.

As for the intercooler, ask the seller if it has been leak tested - don't want one of those!! And just take a good look at where the entry/exit pipes are, and what diameter they are.

The location of the entry/exit pipes is key as to whether it is going to be a front mount or top mount.

Coxy

Fri Mar 18, 2005 11:13 pm

Ok. I think I got a scoop. A guy has offered me a GU copy (by FRP) for $80 is this ok??

Also with the pipes coming out... which do I want? both out the same way or one each direction.. :armsup:

I get the feeling the both the same way is the front mount.. Will keep posted.. anyone else gunna give this conversion a go??? I have a mate who owns a radiator place. i'm sure he can help me plumb this all together

Please check this out will it do?? :?:

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... 73164&rd=1

Or perhaps this one is better :roll:

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... 40263&rd=1

This one looks awesome

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... 22468&rd=1

Sorry there are so many links, but since I dont know the difference between top and front mount...unless they say. I dont want to let a good cooler get away.. Please advise which is best for my application.

Remembering I have a Mk with plenty of room under the bonnet
Thanks guys...really appreciate the help I'm getting YOU GUYS ROCK !!! :armsup:

Post by **coxy321** » Sat Mar 19, 2005 11:13 am

I reckon the Subaru one would be the best of those. The plate with mounting holes will make it easy to bolt down. The only thing is that you would probably have to remove the section with the blow off valve, and get another section made up to replace it.

Mounted as a top mount, all you would need is a few 90 degree piping sections to get the pipes to run back over to the passenger side where the turbo is.

It looks like it is built a bit stronger and would last longer that the others there. You should jump on ebay again and have a look at intercooler piping kits too.

Just remember that the WHOLE system has to be 100% air tight when you're finished.

Might be an idea to also run some steel type fly-screen (fly-wire) over the exposed side of the intercooler so bugs etc. dont block it up.

Coxy

Post by **bilby** » Sat Mar 19, 2005 11:43 am

Team Carpet RC Vehicles wrote:After reading that link.. I have a little Question now. I have a 1986 Mk SD33T.. Needless to say some power might be nice.. Currently running 2.5" exhaust no mufflers... Whats all this turbo boost/Fuel adjusting thing.. Is it possible to dig some ponies out of this beast?? Its still a big heavy thing.... But can a few Hp be found ??????

run it with LPG :lol:

tap it in before the turbo as gas is cold it keeps turbo temps down ( more boost available ) and it increases diesel burn rate to about 90% i think :armsup:

Thu Apr 28, 2005 3:37 am

Hey guys.. quick update .. got the $$ ready is this the inter.. I want.. comments please.. Suits NISSAN. has all the extra bits .. what do we think?? and whats it worth?
http://cgi.ebay.com.au/ws/eBayISAPI.dll ... Track=true

Dammit pick up only

Post by **totto** » Thu Apr 28, 2005 8:20 am

Team Carpet RC Vehicles wrote:After reading that link.. I have a little Question now. I have a 1986 Mk SD33T.. Needless to say some power might be nice.. Currently running 2.5" exhaust no mufflers... Whats all this turbo boost/Fuel adjusting thing.. Is it possible to dig some ponies out of this beast?? Its still a big heavy thing.... But can a few Hp be found ??????

I'm running 11 psi in mine for the moment (same car, year and engine), but i'm awaiting an intercooler before i go further. Had to adjust the wastegate and build a 3-inch exhaust. No diesel adjustment or ic yet.

in here are some picures...
http://www.outerlimits4x4.com/PHP_Modul ... hp?t=17281

Another guy up here ran 17.5 psi with a cut-down Volvo FH12 truck intercooler and adjusted dieselpump, but i'll probably settle for something in between... :cool:

Post by **muzza_fattire** » Thu Apr 28, 2005 9:15 am

coxy321 wrote:You know the theory that things expand with heat?? Well so does oxygen particles, and they also shrink when they get cooler.

Particles don't shink or expand - The distance between particles changes which makes things expand/contract...

Year 7 science...

Post by **Patroler** » Thu Apr 28, 2005 9:34 am

fish_man wrote:shouldn't be changing gears in water crossings

Blow off valves aren't related to gearchanges, they open when you back off the throttle - when the pressure between throttle body and engine turns to vacuum, and then dump the positive pressure on the turbo side of the throttle body.
Not much use if u aint got a throttle body.
Also on most factory petrol turbo cars the BOV vent is plumbed back into the intake between the intake of the turbo and the airflow meter to minimise noise and because the air thats been vented has already been measured by the airflow meter (unless you have a map sensor) and fuel has been calculated for that amount of air... So in that setup water couldn't be sucked in. :finger:

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