Making the au i6 headwork count?

**Stav** · 21-11-2006, 09:32 PM

I have to ask this question to all in internet land.Has anyone got a real measureable real life improvement from cylinder head porting? I know that windsor heads with a port can get terrific gains but when it comes to these sixes it seems that the best in the business are yet to provide a real measure of increase.

Has anyone got any real life gains?

NeishaXR8_347 · 21-11-2006, 10:03 PM

In my opinion they dont need much work, just a tidy up on the short turn radious's and remove all casting marks and can benifit from cutting down the intake guide and shaping them into a point so it cuts and splits the air rather then hitting a round area. Thats all we do at work but if **** factor is what is wanted then we will do mega port but it does nothing, unless the flow is needed. Ill ask you this how many people get heads ported and then do nothing to the intake manifold? or make sure things align properly.

There is no point getting a head ported so it will flow 450hp when they struggle to make 300hp.

**Stav** · 21-11-2006, 10:26 PM

Yes but these heads die at around 470 lift so putting a bigger lift cam than this is well..useless.

What sort of gains have you seem in real life though?

Gianz · 22-11-2006, 08:23 AM

Quote:

Originally Posted by neishaxr8

In my opinion they dont need much work, just a tidy up on the short turn radious's and remove all casting marks and can benifit from cutting down the intake guide and shaping them into a point so it cuts and splits the air rather then hitting a round area. Thats all we do at work but if **** factor is what is wanted then we will do mega port but it does nothing, unless the flow is needed. Ill ask you this how many people get heads ported and then do nothing to the intake manifold? or make sure things align properly.

There is no point getting a head ported so it will flow 450hp when they struggle to make 300hp.

someone needs to do their homework and read a book on aerodynamics. cutting down the intake guides and shaping them into a point to apparently "cut and split the air" is far beyond the truth and crazy. my advice, go and see jim mock motorsport, he will show you "real porting" and the exact gains you can expect. i will be getting mine done soon and i will post the results once its done.

**Stav** · 22-11-2006, 04:52 PM

Quote:

Originally Posted by Gianz

someone needs to do their homework and read a book on aerodynamics. cutting down the intake guides and shaping them into a point to apparently "cut and split the air" is far beyond the truth and crazy. my advice, go and see jim mock motorsport, he will show you "real porting" and the exact gains you can expect. i will be getting mine done soon and i will post the results once its done.

Please do post up your results as far as 1/4 mile differences if possible. I would like to see what a great head port will do.I am still yet to be convinced or seen real gains from head porting so far.

. While I have my own theories on porting I have read these from engineering books which I am skeptical about.So my thoughts dont really count unless I put down the numbers at the track.

Well see these results next june /July.

NeishaXR8_347 · 22-11-2006, 06:33 PM

Jim mock please go and see a real machinist, Have you seen a job from say Flow Craft? Give him a ring and tell him to stop all his guide pointing on his 10 sec engines.

Sapper · 22-11-2006, 06:44 PM

Quote:

Originally Posted by neishaxr8

Jim mock please go and see a real machinist, Have you seen a job from say Flow Craft? Give him a ring and tell him to stop all his guide pointing on his 10 sec engines.

Are these 10 sec engines falcon I6's? If not, what has he done with the Falcon I6? Useless is interested in what can be done on the SOHC I6 which is currently a tough nut to crack. There are plenty of other motors in cars running 10's but if this guy is getting the SOHC I6 into the 10's, why didn't anyone say something before? There are a lot of us looking to find some concrete information about good head work for our motors and if someone's cracked it, it would be nice to see who they are and what they've done.

Sapper · 22-11-2006, 08:56 PM

Quote:

Originally Posted by Gianz

someone needs to do their homework and read a book on aerodynamics. cutting down the intake guides and shaping them into a point to apparently "cut and split the air" is far beyond the truth and crazy. my advice, go and see jim mock motorsport, he will show you "real porting" and the exact gains you can expect. i will be getting mine done soon and i will post the results once its done.

Can i ask a few questions so we can get an idea for what gains you'll be getting from the head work. What engine do you have mate? What have you done to it? What are you going to have done to it for the head work? What power are you putting out now? Please be specific.

Thanks in advance.

Gianz · 23-11-2006, 09:17 AM

Quote:

Originally Posted by hot xr6

Can i ask a few questions so we can get an idea for what gains you'll be getting from the head work. What engine do you have mate? What have you done to it? What are you going to have done to it for the head work? What power are you putting out now? Please be specific.

Thanks in advance.

Yeah No problems,

I've got a series II VCT Engine.
Currently fitted with:
Complete HMS exhaust system.
large tickford air intake snorkle with pod filter in air box followed by a 3 inch intake.
autolite spark plugs + spiral leads (made a noticable difference)
unichip ecu (soon to be changed)
Current power output is 135 kW @ rears (somehow lost power after unichip??)

So what do i want to accomplish.
cc and polish every chamber and bump up compression via jmm multi layer head gasket.
Port and polish where needed, only to remove casting imperfections and insert stainless steel valves.
Camshaft would be good but i have not heard of anything amazing for the vct engine.

Aim is to hopefully reach the 180+ rw kW of good smooth power.

So basically i want what everyone else wants.....MO POWER! without taking away the awesome characteristics and sounds of a VCT i6. :hihi:

any suggestions?

EvilChief · 22-11-2006, 01:23 AM

for headwork to work effectively you need to match it with an appropiate cam.

We matched my camshaft with a reasonable head port, port match and increased compression.

It showed good improvements over the stock condition, the combination of improvements painted the big picture thou.

MRJUCY · 22-11-2006, 05:51 PM

Tickford

stiddy · 22-11-2006, 06:43 PM

Jim Mock Motorsports LMAO... ahh Gianz, heres an idea, you go see JMM and get your free kw's and let the rest of us go to reputable workshops and get some real work done

poolkeeper · 22-11-2006, 06:47 PM

Quote:

Originally Posted by stiddy

Jim Mock Motorsports LMAO... ahh Gianz, heres an idea, you go see JMM and get your free kw's and let the rest of us go to reputable workshops and get some real work done

Id have to agree, very rude in answering my questions about their parts.

stiddy · 22-11-2006, 06:55 PM

Quote:

Originally Posted by D1XR2C

Id have to agree, very rude in answering my questions about their parts.

You should ask them about the 25rwkw Free Voucher you get when you get a dev5 cam.. :Up_to_som

**Stav** · 22-11-2006, 07:03 PM

Guys please dont fight or poke fun at particular people or businesess.Its not good. Hot xr6 thanks mate. This is what I am chasing..some real verifiable statistics from head porting. I have information in front of me which expalains head porting on a few heads .An example is a 2 litre sohc pinto engine. They show a 25% increase in horsepower at the wheels. A kent crossflow head..up to 30% increase.

If these results are true then why the heck am I yet to see on this forum one person who has done the head up and gained substantial better 1/4 mile times or substantial increase in power on independant dynos ? Without having a dig at anyone why hasnt anyone done it? Including the e series owners? The ba's are achieving 168rwkws na on the same dyno I get 131? Same capacity but more power.Sure they have a dohc but it does show what real potential that these sohc motors have.

NeishaXR8_347 · 22-11-2006, 07:16 PM

Quote:

Originally Posted by useless

Guys please dont fight or poke fun at particular people or businesess.Its not good. Hot xr6 thanks mate. This is what I am chasing..some real verifiable statistics from head porting. I have information in front of me which expalains head porting on a few heads .An example is a 2 litre sohc pinto engine. They show a 25% increase in horsepower at the wheels. A kent crossflow head..up to 30% increase.

If these results are true then why the heck am I yet to see on this forum one person who has done the head up and gained substantial better 1/4 mile times or substantial increase in power on independant dynos ? Without having a dig at anyone why hasnt anyone done it? Including the e series owners? The ba's are achieving 168rwkws na on the same dyno I get 131? Same capacity but more power.Sure they have a dohc but it does show what real potential that these sohc motors have.

Same capacity but have you seen the heads up close and stripped? When you look down the intake port in the ba6 head you can almost see all of the intake valve's so the air basically falls in and falls out, it doesnt have to turn much which will cause turbulance. With the pointed guide idea what i was getting at is like the nissans and all new designed heads, they are basically tappered and will be less of a restriction also having the slightly backcut will help on the intake valve aswell. Im not saying these tappered guides will give you 10kw but im just saying the more little things you do to help it will all add up in the end. The bigger port is not always the better port, not even in a turbo, ezy10's crossflow was an unported head he lost power and times with a portjob.

Shaun.

Gianz · 22-11-2006, 07:29 PM

all im saying is that jmm has definately done his homework to an extent and has, in some cases the figures to prove it. If anyone knows a ford performance shop that has spent as much r&d time as jmm and also has ported heads to suit our i6's please let us know before i get one. i spent many years as a race tunner working on moto gp bikes and i can sure tell the difference between good and bad port jobs. in many cases extensive porting radically changes the characteristics of an engine, especially in power delivery, when what we all want is smooooth clean power, so often as mentioned its just a matter of cleaning up what the original castings have left behind.

**Stav** · 22-11-2006, 08:47 PM

Ok so whos got the results on this forum from head porting? 2 cases that I have heard of proffessionally done made no real difference on the dyno or the track.

FS5 · 22-11-2006, 06:45 PM

mate as you know with mine i picked up about 25nm of torque and lost a couple of kw.
i think with your edit and a good tuner you will get some good results.with mine i think its to much for the ecu to handle ,mine flowed 368 @500 thou.its like putting in a bigger cam you loose a lot of vacume @ idle and the ecu dosen't like this.it throws heaps of fuel in and generaly has a spaz.to get it idle half decent and behave itself i had to have the cam advanced 5 degrees .but with your edit they should be able to tune this out.
i do believe there are good gains to be had with a cam matched to the headwork and a decent tuner.
while we are on the subject has anyone had a bbm manifold flow tested yet?maybe these are a restriction also to what a ported head can do

stiddy · 22-11-2006, 06:51 PM

FS5, the BBM's on these engines make well over 300rwkw in a forced fed application, I dont see how they can be a restriction n/a. I could be wrong, but I just dont see them being a restriction.
I think the restriction is lack of compression, head and a small cam..

**Mechan1k** · 23-11-2006, 07:34 AM

Quote:

Originally Posted by stiddy

FS5, the BBM's on these engines make well over 300rwkw in a forced fed application, I dont see how they can be a restriction n/a. I could be wrong, but I just dont see them being a restriction.
I think the restriction is lack of compression, head and a small cam..

I know someone who has ditched the BBM for the older log-style manifold (which has beem ported/extrude honed to suit his head .... I don't have exact spec on what was done to the head though.

mik · 22-11-2006, 10:18 PM

i dont think huge gains are possible na, because the variable intake runners and long bendy air intake and variable runners, take the edge off extra efficiancey of head work,etc, too many angles slow down air speed, ........would love too see individual throttle bodies velocity stacks, big cam and after market ecu or flash tuned if possible, no proof just my theory

jonbays · 23-11-2006, 09:18 AM

Quote:

Originally Posted by mik

i dont think huge gains are possible na, because the variable intake runners and long bendy air intake and variable runners, take the edge off extra efficiancey of head work,etc, too many angles slow down air speed, ........would love too see individual throttle bodies velocity stacks, big cam and after market ecu or flash tuned if possible, no proof just my theory

This is real world here. The Falcon six is a long stroke tractor engine with all the wrong bore stroke ratios to rev and get good flow from a head limited by the width of the bore and the short height of the head and the 90 degree turns of the inlet and exhaust.

Sapper · 23-11-2006, 11:17 AM

Hmmm, started doing a bit of research on engine theory and i think that the engine internals need to be balanced with the head work. Here's a section of text from wikicars thats a simple explanation of this.

Quote:

One important factor in engine design is the rod/stroke ratio. Rod/stroke ratio is the ratio of the length of the connecting rod to the length of the crankshaft's stroke. An increase in the rod/stroke ratio (a longer rod, shorter stroke, or both,) results in a decrease in piston speed. However, again due to strength and size concerns, there is a limit to how long a rod can be in relation to the stroke. A longer rod (and consequently, higher rod/stroke ratio,) can potentially create more power, due to the fact that with a longer connecting rod, more force from the piston is delivered tangentially to the crankshafts rotation, delivering more torque. A shorter rod/stroke ratio creates higher piston speeds, but this can be beneficial depending on other engine characteristics. Increased piston speeds can create tumble or swirl within the cylinder and reduce detonation. Increased piston speeds can also draw fuel/air mix into the cylinder more quickly through a larger intake runner, promoting good cylinder filling.

An engine where the bore dimension is larger than the stroke is commonly known as an oversquare engine, and such engines have the ability to attain higher RPM. Conversely, an engine with a bore that is smaller than its stroke is an undersquare engine. Respectively, it cannot attain as many RPM, but is liable to make more torque at lower RPM. In addition, an engine with a bore and stroke that are the same is referred to as a square engine.

Question is, which way to go? Do we accept the fact that getting air into the chamber is always going to be tough and make the most of what there is or do we go after getting as much air into the chamber as possible?

Gianz · 23-11-2006, 01:43 PM

Knowing all this, we should be very greatful that there are people out there making some attempt to find whats the best combination of porting / headwork, cams ect for these so called "tractor engines". The real question is...who has worked it out with real figures to prove it? and of course who is the best man for the job?

poolkeeper · 23-11-2006, 05:43 PM

Quote:

Originally Posted by Gianz

Knowing all this, we should be very greatful that there are people out there making some attempt to find whats the best combination of porting / headwork, cams ect for these so called "tractor engines". The real question is...who has worked it out with real figures to prove it? and of course who is the best man for the job?

One company that comes to mind, when heads and porting is being talked about is these guys...

http://www.trickandmanswetoracing.com.au/

mik · 23-11-2006, 10:21 PM

Quote:

Originally Posted by jonbays

This is real world here. The Falcon six is a long stroke tractor engine with all the wrong bore stroke ratios to rev and get good flow from a head limited by the width of the bore and the short height of the head and the 90 degree turns of the inlet and exhaust.

probably some truth in that, but can always be tinkered with, shouldnt be too much trouble to get decent power , the xr8 motor can be made to rev ok with 105 mm stroke , my brothers 3.0 supra has a similar bore stroke ratio and runs happily too 6400 +

jonbays · 24-11-2006, 10:31 AM

Quote:

Originally Posted by mik

probably some truth in that, but can always be tinkered with, shouldnt be too much trouble to get decent power , the xr8 motor can be made to rev ok with 105 mm stroke , my brothers 3.0 supra has a similar bore stroke ratio and runs happily too 6400 +

BA V8's bore stroke ratio is not ideal look how much better the 4.6 engine can be tuned in the US mustangs.

Even so the BA 5.4 heads 3V or 4V are streets ahead of the AU six.

E-AU sixes are truly tractor engines with BS ratio for Torque and you can't change that and make them something else. You can get good mid range and a flat torque curve 3-5000rpm but going further they will just get very peaky and blow up from the high piston speeds.

Sapper · 24-11-2006, 11:43 AM

Can we start having actaul figures put down rather than "this is good" or "this is bad" type comments. If the I6 engine has a bad/good characteristic, please quantify this. That way, we can start to get a genuine idea of what can be changed. Jonbays, what do you reckon is a ratio we should target for our rod length/stroke ratio and our bore/stroke ratio? You never know, it may be possible to get a hold of internals that helps fix up these problems.

For instance, the Falcon bore/stroke ratio is 0.93, the supra bore/stroke ratio is 0.91 for a MkIII and 1.0 for a MkIV. The AU's have a rod length of 153.67mm which gives a rod length/stroke ratio of 1.55. Now, how can we apply this? Well, if we wanted to reduce the rod length/stroke ratio, we could put some EL internals in (EL rod length is 149.33) and possibly shave the head to get back some compression. It will take more than just those little steps but you see what i'm getting at.

So what does this have to do with headwork? Well, according to my previous post, the reduced rod length/stroke ratio will increase flow for large ports and reduce detonation. Hopefully, making the most of a big porting job. Question is, can we make the ports flow well enough for this to be useful? Otherwise, it may be better to go the other way and try and maximise torque. That is, if there's enough room at the base of the cylinders for longer rods.

Does anyone else have any information to add to this list? What would be useful at this time is some information about the head, flow rates, valve and port diameters etc and what workshops offer what headwork options. I've heard that the Au head is good for 300bhp. Has anyone tested this? What were the results. When i get some time i'll dig through some old posts on here and on FordMods to find some porting results.

Please feel free to correct any information i've posted but if you do, please supply some evidence as i'd like to check it out for myself.

FS5 · 22-11-2006, 10:36 PM

when i was talking to jmm about there heads he told me i would gain around 10rwk for the streetfighter and 14rwk for race spec .
i decided to get mine professionaly done by headsense ,along with the 3 angle valve cut.like i said i lost a couple of kw,but in all fairness the head i pulled off our series 2 was different to the series 1 i had ported.
i've been talking to some speed way guys and they seem to think you can go to big with your porting (going to big on the exhaust side)and kill performance .from what i understand airspeed was more important than the flow rate????