Ultimate Racing VQ35 Heads
04-17-2006, 01:19 AM
#6
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Hope its not worth much...
Some of its ok, but some is completely wrong.
Who ever is doing it obviously has no idea of what air does in a head.
Knife edge on the intake is wrong.
The Combustion chambers have been polished BUT the valves havn't been deshrouded.
Backsides of the valves havn't been touched.
Unfortunatly what has been done has only about 10% effect of what could be acheived.
IMHO more can be acheived in an hour to make hp than what has been done there.
Some of its ok, but some is completely wrong.
Who ever is doing it obviously has no idea of what air does in a head.
Knife edge on the intake is wrong.
The Combustion chambers have been polished BUT the valves havn't been deshrouded.
Backsides of the valves havn't been touched.
Unfortunatly what has been done has only about 10% effect of what could be acheived.
IMHO more can be acheived in an hour to make hp than what has been done there.
Last edited by Spanners; 04-17-2006 at 01:37 AM.
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04-17-2006, 02:54 AM
#8
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Originally Posted by Spanners
Hope its not worth much...
Some of its ok, but some is completely wrong.
Who ever is doing it obviously has no idea of what air does in a head.
Knife edge on the intake is wrong.
The Combustion chambers have been polished BUT the valves havn't been deshrouded.
Backsides of the valves havn't been touched.
Unfortunatly what has been done has only about 10% effect of what could be acheived.
IMHO more can be acheived in an hour to make hp than what has been done there.
Some of its ok, but some is completely wrong.
Who ever is doing it obviously has no idea of what air does in a head.
Knife edge on the intake is wrong.
The Combustion chambers have been polished BUT the valves havn't been deshrouded.
Backsides of the valves havn't been touched.
Unfortunatly what has been done has only about 10% effect of what could be acheived.
IMHO more can be acheived in an hour to make hp than what has been done there.
I would love to hear more on how we can make the heads better. Thank you for your input,
Az
04-17-2006, 01:40 PM
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Just a couple of tidbits for now.
If you plot camshaft openeing over time you will end up with a bell shaped curve.
If you work out the middleof the curve based on lift and area inside it, you will find that, XX% of the time involved is at relativly low lift (due to opening and closing events.)
eg: if you have 65% of the camshaft events at 5mm or under lift, then you want to acheive the most ariflow you can in those situations.
If you see the picture I 'drew' on below you will not 3 areas.
1: Shrouding of the valve into the side of the head. The ridge you can see wants to be almost completly gone and the deshround continued around as much of the valve as possible. This is very often a issue with inlet valves as they are basically as big as the head will take.
2: Same thing, but on the firing side of the valve.
You can see/feel a step or transition here.
Its from the machining of the head for the valave seat.
Once again, remove it all.
On a proper race head, we'd blend the whole top of seat into the head, and then have a skim taken off the seating face as you always end up running the mop overe the face.
3: As the seats are actaully an insert there is ALWAYS a transition between the head and seat which is UGLY!
It looks like on this head that someone has had a go at it, but one of the other photos still shows a pretution.
For DIY at home jones, best thing to get a is a piece of 6mm stainless bar, and cut a slot down the top with a hacksaw.
Slot a piece of emery paper into it and wrap tightly. Secure base with piece of duct tape.
This is what we call a 'mop' and is perfect for getting in and doing backside of valve seats and deshrouding. You will have able to grind both seat and heat at once to blend them.
If you plot camshaft openeing over time you will end up with a bell shaped curve.
If you work out the middleof the curve based on lift and area inside it, you will find that, XX% of the time involved is at relativly low lift (due to opening and closing events.)
eg: if you have 65% of the camshaft events at 5mm or under lift, then you want to acheive the most ariflow you can in those situations.
If you see the picture I 'drew' on below you will not 3 areas.
1: Shrouding of the valve into the side of the head. The ridge you can see wants to be almost completly gone and the deshround continued around as much of the valve as possible. This is very often a issue with inlet valves as they are basically as big as the head will take.
2: Same thing, but on the firing side of the valve.
You can see/feel a step or transition here.
Its from the machining of the head for the valave seat.
Once again, remove it all.
On a proper race head, we'd blend the whole top of seat into the head, and then have a skim taken off the seating face as you always end up running the mop overe the face.
3: As the seats are actaully an insert there is ALWAYS a transition between the head and seat which is UGLY!
It looks like on this head that someone has had a go at it, but one of the other photos still shows a pretution.
For DIY at home jones, best thing to get a is a piece of 6mm stainless bar, and cut a slot down the top with a hacksaw.
Slot a piece of emery paper into it and wrap tightly. Secure base with piece of duct tape.
This is what we call a 'mop' and is perfect for getting in and doing backside of valve seats and deshrouding. You will have able to grind both seat and heat at once to blend them.
04-17-2006, 06:32 PM
#14
Originally Posted by upperguy
Yeah, but Dave at headgames is just the man, hands down.
Upperguy(was half pitched when he shook his hand)
Upperguy(was half pitched when he shook his hand)
I'm going to take some pictures of the last set of heads that Dave did for me later this week, complete work of art!
I'll call Dave tomorrow and see if he could post some details on what he does to make so much power with these heads. The last set made over 125hp by just adding his heads, and my new set are even more impressive - I think he's got these heads pretty much figured out.
04-17-2006, 09:22 PM
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Originally Posted by Philthy
I agree 100% with you.
I'm going to take some pictures of the last set of heads that Dave did for me later this week, complete work of art!
I'll call Dave tomorrow and see if he could post some details on what he does to make so much power with these heads. The last set made over 125hp by just adding his heads, and my new set are even more impressive - I think he's got these heads pretty much figured out.
I'm going to take some pictures of the last set of heads that Dave did for me later this week, complete work of art!
I'll call Dave tomorrow and see if he could post some details on what he does to make so much power with these heads. The last set made over 125hp by just adding his heads, and my new set are even more impressive - I think he's got these heads pretty much figured out.
04-17-2006, 10:02 PM
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Those are some pics which I found floting around on the Internet. These heads have been done by HeadGames Motorworks. The link
Last edited by aalzuhair; 04-18-2006 at 04:47 AM.