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 7765 Posts Member #: 74 I pick holes in everything.. Chief ancient post excavator |
12th Feb, 2010 at 01:40:16pm
On 12th Feb, 2010 gr4h4m said:
Vegard, supercharged my head made very good power with 33.3 and 27.8 with a std cam. In fact I think this is why it was so good, (61ATW) as it shocked us at the time, however I didn't know the valve size then. IMO the sizes work well on a FI car. I understand that they are a little big NA. IMO you need a good exhaust size to get all those gasses out when your forcing everything in. On the 1275 length valve: My car ran with odd size valves from 06 until now, when I'm taking the opportunity to have the head ported. I had the head rebuilt 12 months ago because I was trying to trace a problem I think the guy reamed them out too much as is smoked ever since. Maybe I have been lucky on a couple of fronts like not blowing a hole in the wrong spec inlets being used as exhaust valves. I have used a std cam. I have to point out that I'm running shims under the rockers and for the last 18 months I've been running 1.5's. the car does about 3-5k a year inc some track days. I drive it with good sprinkling of mechanical sympathy. Probably been lucky with Morspeed sinking the valve seat. After loads of chats with Phil and my RR operator. I have gone with all stainless race spec 1275 valves 33.3 inlets and 29mm exhausts which I have at a machine shop for them to turn down to match the old ones removed. Is this the correct way to do it maybe not, it would be nice to have 295 valves, but I don't want to go back a size to 26.x mm, for the points above. I might be wrong in all this but it has worked well since 06, I hope even better with a cam designed for a supercharger and a bit of Turbo Phil porting magic. I will however check the clearance before I fire it up... maybe with the blue tac test. But with my luck recently, and if the exhaust valves do touch the block I'm not sure of my next move.. Why didn't you fir a 940 in the first place? HAve you got a picture of the exh seat with a 29.4mm 94 valve? I'm very curious on what the throat looks like. On 13th Jul, 2012 Ben H said:
Mine gets in the way a bit, but only when it is up. If it is down it does not cause a problem. |
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 4890 Posts Member #: 1775 Post Whore Chester |
12th Feb, 2010 at 01:50:05pm
V , Morspeed fit the mis match in the first place, I purchased the head form them in this state and I knew a lot less than I even do know, which isn't much.
I run a supercharger and I don't care the TB is on the wrong side.
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 1137 Posts Member #: 1450 Post Whore Near Paris - France |
14th Feb, 2010 at 08:43:10pm
Back to V quizz :
Rusty by nature
On 23rd Jun, 2008 paul wiginton said:
They said "That sounds rough mate." I said "Cheers it cost me a fortune to make it sound like that!" |
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7765 Posts Member #: 74 I pick holes in everything.. Chief ancient post excavator |
14th Feb, 2010 at 09:54:15pm
The chamber does indeed overhang the block. The chamber shape there's nothing wrong with, it's the lack of bore that's wrong On 13th Jul, 2012 Ben H said:
Mine gets in the way a bit, but only when it is up. If it is down it does not cause a problem. |
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 12307 Posts Member #: 565 Carlos Fandango Burnham-on-Crouch, Essex |
14th Feb, 2010 at 09:57:06pm
On 14th Feb, 2010 Vegard said:
I THINK that 26,5 is safe. That's the biggest exhaust you can fit with no worries, Edited by Joe C on 14th Feb, 2010. On 28th Aug, 2011 Kean said:
At the risk of being sigged... Joe, do you have a photo of your tool? http://www.turbominis.co.uk/forums/index.p...9064&lastpost=1 https://joe1977.imgbb.com/ |
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4890 Posts Member #: 1775 Post Whore Chester |
22nd Mar, 2010 at 08:21:00pm
Well just for an update... Everything cleared and the car started up today... A big thanks to Phil..
I run a supercharger and I don't care the TB is on the wrong side.
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1137 Posts Member #: 1450 Post Whore Near Paris - France |
22nd Mar, 2010 at 09:10:14pm
Cool !
Rusty by nature
On 23rd Jun, 2008 paul wiginton said:
They said "That sounds rough mate." I said "Cheers it cost me a fortune to make it sound like that!" |
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1137 Posts Member #: 1450 Post Whore Near Paris - France |
22nd Mar, 2010 at 09:10:22pm
Cool !
Rusty by nature
On 23rd Jun, 2008 paul wiginton said:
They said "That sounds rough mate." I said "Cheers it cost me a fortune to make it sound like that!" |
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4890 Posts Member #: 1775 Post Whore Chester |
22nd Mar, 2010 at 09:16:42pm
will do hoping for a few more Banana's this time but we will see. I'm not sure if the carb will flow enough now, as the bike carb is only a 38.. I run a supercharger and I don't care the TB is on the wrong side.
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4890 Posts Member #: 1775 Post Whore Chester |
22nd Mar, 2010 at 09:16:45pm
will do hoping for a few more Banana's this time but we will see. I'm not sure if the carb will flow enough now, as the bike carb is only a 38.. I run a supercharger and I don't care the TB is on the wrong side.
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4890 Posts Member #: 1775 Post Whore Chester |
31st Mar, 2010 at 10:16:20pm
Well a Turbo Phil head and a 266 cam 3deg uplift across the map up to 67ATM from 58. This was at 5800 and it was still pulling. Rev limiter 6k. With more guts to rev to say 6500 I recon you could see 70.. not bad from a 998
I run a supercharger and I don't care the TB is on the wrong side.
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 4629 Posts Member #: 20 My sister is so fit I won't show anyone her picture Lake District |
31st Mar, 2010 at 10:24:27pm
Good stuff ! Am I being daft but was does ATM mean ? |
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4890 Posts Member #: 1775 Post Whore Chester |
31st Mar, 2010 at 10:35:12pm
Sorry I meat ATW. At The Wheels I run a supercharger and I don't care the TB is on the wrong side.
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4629 Posts Member #: 20 My sister is so fit I won't show anyone her picture Lake District |
31st Mar, 2010 at 10:52:42pm
Aaaah ! Good stuff. So a 9hp gain at the wheels. :) |
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4890 Posts Member #: 1775 Post Whore Chester |
1st Apr, 2010 at 04:00:30pm
yep.... flowtastic I run a supercharger and I don't care the TB is on the wrong side.
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1137 Posts Member #: 1450 Post Whore Near Paris - France |
3rd Apr, 2010 at 03:08:26pm
I am being lazy, what was the boost again ?
Rusty by nature
On 23rd Jun, 2008 paul wiginton said:
They said "That sounds rough mate." I said "Cheers it cost me a fortune to make it sound like that!" |
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4890 Posts Member #: 1775 Post Whore Chester |
3rd Apr, 2010 at 04:05:05pm
boost is 7 - 9psi dependant of the revs. I will have to scan the graph. I run a supercharger and I don't care the TB is on the wrong side.
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1137 Posts Member #: 1450 Post Whore Near Paris - France |
3rd Apr, 2010 at 07:14:14pm
cheers.
Rusty by nature
On 23rd Jun, 2008 paul wiginton said:
They said "That sounds rough mate." I said "Cheers it cost me a fortune to make it sound like that!" |
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