Where To Get Head Work Done?

[SLED]

i will be keen sled, but i should mention i will be on my quad....

can that big fuel guzzling twin turb beat a 4 cyl?

you better have your front wheels in the air if you hope to keep up.

i certainly will have

lol Darren, I think the 2.7 tonne I'm hauling may give your quad a slight advantage

[whatsisname]

Brendan, so it was your Stag' at BW! I thought that might of been your beast. I had a look at the spec's list a week or so back (whilst lending a hand at BW and having just taken my 33 down there) thought it sounded familiar.

Sorry to hear (see, smell, and get gassed out by) the cracked block issue She was looking like a smoke machine for a while. Poor old Andrew, he pulled the head apart twice in the process of that job (initial and then to diagnose the issue) and then Troy got a go, along with the bottom end. I had a look at the crack in the block, makes me think it was a little 'unhealthy' prior to the latest mod's.

And here I was suggesting for you to 'do' the bottom end whilst you were planning to do the head... I didn't mean that kind of 'do'!

[Tangles]

Brendan, so it was your Stag' at BW! I thought that might of been your beast. I had a look at the spec's list a week or so back (whilst lending a hand at BW and having just taken my 33 down there) thought it sounded familiar.

Sorry to hear (see, smell, and get gassed out by) the cracked block issue She was looking like a smoke machine for a while. Poor old Andrew, he pulled the head apart twice in the process of that job (initial and then to diagnose the issue) and then Troy got a go, along with the bottom end. I had a look at the crack in the block, makes me think it was a little 'unhealthy' prior to the latest mod's.

And here I was suggesting for you to 'do' the bottom end whilst you were planning to do the head... I didn't mean that kind of 'do'!

lol at your lungs, sorry I know, what a head-f'k

yeah, but very happy with the outcome.

prior to going in the car was faultless, honestly. as far as I know....

boostworxs are awesome, I wasnt worried about the time (7.5 weeks) but the family was stuck-up me

looked after me car-wise and cost-wise, and again, very happy with the outcome

will do more tuning time in a cple months time, prior to next service + the additional fuel mockup

oh- whats that about the block? maybe I dont know something , , , lol

[whatsisname]

Ha-ha no harm done mate. Yeah I felt sorry for you, and the guys trying to sort out the issues.

Shaun is as good as they come in the performance workshop game. His Boostworx business certainy gets busy, but I guess that to be expected when you're recognised as being a decent and sensibly priced outfit.

Maybe it was another bottom end with a cracked block? I knew your RB had issues after the head work, and I was checking out a cracked RB block sitting on the eng' stand near your Stag' on the hoist. Then again, given the number of RB motors that are in at BW at any given time it might have been totally unrelated to your beast.

Anyway, it's up and running now and that's the main thing. And with a bit more work (bigger turbo) you should start to see the benefits of that head work.

[Tangles]

garrett gt3071r-iw is what Im searching for

cheers all

great to drive, loving it

[mid life crisis]

i want first dibs on ya high flow tangles if ya sell it

[dangerman4]

2k for a 3071, or 3k for my 3582 plus etm manifold.

[ovrtym33]

or $1,100 for my gt30/40 with .82 external gate housing (which u can get changed for IW)

[The Bogan]

Been investigating head work and polishing the ports is bad due to the fact the air sticks to the smooth surface creating drag whereas a rougher surface creates a thing (cannot think of the correct word) that lets the air flow more freely. Like the rough skin of a shark helps it go through the water without creating much drag.

Was told to leave the ports with the machine marks or shoot peen them with glass beads to get the disired effect.

[mid life crisis]

that applys more too a n/a motor reason on a n/a if the ports are too smooth the fuel goes into the chambers as droplets where if the ports have a semi machined surface it atomises the fuel more into a mist . this also applys more to carby motors than injected ones where the fuel is a finer spray anyway . with forced induction the fuel goes in a shitload faster than been drwn in on a n/a motor.

and too the guys trying to sell me there big turbos lol def not needed in my case but a nice steel wheel highflow would suit my car and mods nicely -)

[dangerman4]

All i can say Dean is Soft....

very soft...

time to live a little me thinks, mid life crisis or not a highmount gt35 will make you feel 10 yrs younger.

[mid life crisis]

All i can say Dean is Soft....

very soft...

time to live a little me thinks, mid life crisis or not a highmount gt35 will make you feel 10 yrs younger.

yeah i know dangerman but 20 yrs of racing speedway has calmed me down on the road somewhat time to live a little lol ive done most of it and had fun now just is relax time :-)

[Carbon 34]

Been investigating head work and polishing the ports is bad due to the fact the air sticks to the smooth surface creating drag whereas a rougher surface creates a thing (cannot think of the correct word) that lets the air flow more freely. Like the rough skin of a shark helps it go through the water without creating much drag.

Was told to leave the ports with the machine marks or shoot peen them with glass beads to get the desired effect.

parasitic drag is the word i think???. air flow and liquid dynamics , if its too smooth it actually beads the fuel up , not ideal for sure. you want the best fuel atomization you can get, like a super fine mist ?

this is very true, intakes work better if left glass beaded/sand blasted texture inside .but port matched to the gaskets and intake plenum and all burs removed, extrude honing is a great way to fix up the head but not sure if anyone does it here in Adelaide? (kinda like shooting sandy toothpaste with extreme pressure thru the ports smoothing the walls )

the exhaust side needs to be polished up and flowed , also port matched to gaskets and extractors ,

also by cc'ing the head to balance the power in each cylinder and polishing the combustion chamber to keep the carbon buildups minimized, saves the carbon buildup from misfiring over time or even jamming in the ring lands like abrasives

tidy up the head gasket to match the water jackets as well. a little bur/ slag in the water jacket can cause a lot of hotspots on turbo cars. creates a spot of bubbles which dont transfer heat out of the head correctly, cavitaing the water pump at high rpm if severe, all easy to do for the best insurance and head performance

when my head is due I'll port my own and take photos of it for ya, later this year prob.

I've done a lot of them in my past for formula fords ,datto, formula VW cars. for those of you who want to do it just take your time ...it's not hard to of good info here for the DIY

http://www.sa-motorsports.com/diyport.aspx

Edited January 18, 2009 by sapphiregraphics

[mind_riot]

The 'thing' the rougher surface will create is a thicker boundary layer. The boundary layer is where viscous effects dominate over fluid flow effects, and if you're looking to minimise the amount of effort required to move the intake charge through the head, you want the boundary layer to be as thin as possible (hence the head as smooth as possible).

This is just basic fluid dynamics and is only really half the story. As mentioned previously, the thicker boundary layer MAY prevent fuel from condensing on the walls, I'm not really too sure and there are more qualified people here to answer that. I thought this was more an issue with carby fed cars, to the point where a lot of old cars had their entire intake manifold heated to encourage the fuel to evaporate off the walls.

[SLAPS]

Polish it all up if you want all out 'top' end performance.

If you wish to improve economy and low end torque for a bee's dick loss of top end performance roughen up the inlet. Nothing 0.2psi can't fix.

Edited February 11, 2009 by TheRogue

[mind_riot]

Polish it all up if you want all out 'top' end performance.

If you wish to improve economy and low end torque for a bee's dick loss of top end performance roughen up the inlet. Nothing 0.2psi can't fix.

How will a rougher surface on the inlet improve economy and low end torque? I'm not saying it wont, I'm just saying u haven't really explained your statement and/or given any evidence to back it up.

[mind_riot]

Also just a thought, someone mentioned previously the golf ball and shark skin rough surfaces that reduce drag.......just for the record these are different scenario's to flows within an engine because in one case your talking about external flows and the other is considering an internal flow.

Drag is bad. Drag should be reduced where possible as long as there aren't negative side effects.

There are two types of drag, form drag and skin friction drag. In the case of the shark and the golf ball, the rougher surface will increase skin friction drag (because the rough surface makes the boundary layer turbulent, and the skin friction coefficient is larger for a turbulent boundary layer).

SO WHY DO THIS if it increases drag??? Because in these examples it can reduce form drag by a lot, which more than offsets the increase in skin friction drag.

HOW? The turbulent boundary layer delays flow separation, which is the main cause of form drag.

So if we're talking about an internal flow scenario (where form drag doesn't really apply), such as fluid flow in a pipe for example, a smoother surface will always have less drag than a rough one. Period.

If people are getting good results by 'roughing' up the inlet, it has nothing to do with drag reduction, its due to other effects.

Edited February 12, 2009 by mind_riot