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#16
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Re: Camshafts for the EG33.
At what revs did they say the hydrulic buckets will be a issue?
Tony
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1995 - SVX 700,000 K Mine, DMS Struts to lift car 2in. Tyres Wrangler Silent Armor 235/70R16, PBR Radiator. 6 speed with DCCD and R180 rer diff, Heavy duty top strut mounts front and rear. Speedo correction box fitted. New stero (gave up on the old one). Back seat removed and 2 spare tyres fitted for desert driving. ECUTune SC sitting in the box for the next SVX. 1992 - SVX 255 K Wife (Want to stay Married so not allowed to fit SC) 1992 - SVX Pearl with black roof race car roll cauge etc ready to race. Ex Tasman Targa car. 1995 - SVX Green low k mint condiation. 1995 - SVX Rally car, ex Matts car. Now to be used on track. 1992 - SVX red & Black being converted to Mid Engine. 1995 - SVX Red 143,000 bit rough. Owned 5 others Subaru back to a 1974 1400 GSR. |
#17
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Re: Camshafts for the EG33.
He didn't, said they can rev massive. Porsche run them, makes sense.
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#18
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Re: Camshafts for the EG33.
Quote:
Tony, good news. I now have the stock cam profile completely mapped and found another place for regrind for 350. Thinking massive regrind and super tech 92 mm valves to allow for big changes although prolly not required. Also I know what cam duration the 1200 bhp eg33 runs |
#19
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Re: Camshafts for the EG33.
The problem with the lift with hyd followers, is that the valves are too short, so that the spring binds at 9mm. Using solids and the longer WRX valves lets us use a longer spring, and higher lifts.
Hyd lifters are too heavy for high rpms. Have to use stronger springs to follow the cams, this causes cam/follow wear, and can end up pulling the head off the valve. The lightest valve gear, is needed for high lift with short durations. Harvey.
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One Arm Bloke. Tell it like it is! 95 Lsi. Bordeaux Pearl, Aust. RHD.149,000Kls Subaru BBS wheels. 97 Liberty GX Auto sedan. 320,000Kls. 04 Liberty 30R Auto Premium. 92.000kls. |
#20
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Re: Camshafts for the EG33.
Quote:
Example, rb20 wil rev to 10,000 +.... http://forum.r31skylineclub.com/index.php?topic=76252.0 |
#21
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Re: Camshafts for the EG33.
Quote:
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Remember that some of the Nissans that have hyd lifters, use finger followers, which eliminates the weight of the hyd from the reciprocating valve train weight. Harvey.
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One Arm Bloke. Tell it like it is! 95 Lsi. Bordeaux Pearl, Aust. RHD.149,000Kls Subaru BBS wheels. 97 Liberty GX Auto sedan. 320,000Kls. 04 Liberty 30R Auto Premium. 92.000kls. |
#22
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Re: Camshafts for the EG33.
Quote:
I will stay out of the debut on valves, I am pretty sure there is info in the RIT mags on this issue. Tony
__________________
1995 - SVX 700,000 K Mine, DMS Struts to lift car 2in. Tyres Wrangler Silent Armor 235/70R16, PBR Radiator. 6 speed with DCCD and R180 rer diff, Heavy duty top strut mounts front and rear. Speedo correction box fitted. New stero (gave up on the old one). Back seat removed and 2 spare tyres fitted for desert driving. ECUTune SC sitting in the box for the next SVX. 1992 - SVX 255 K Wife (Want to stay Married so not allowed to fit SC) 1992 - SVX Pearl with black roof race car roll cauge etc ready to race. Ex Tasman Targa car. 1995 - SVX Green low k mint condiation. 1995 - SVX Rally car, ex Matts car. Now to be used on track. 1992 - SVX red & Black being converted to Mid Engine. 1995 - SVX Red 143,000 bit rough. Owned 5 others Subaru back to a 1974 1400 GSR. |
#23
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Re: Camshafts for the EG33.
Harvey what are bike engines doing with valves?
Tony
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1995 - SVX 700,000 K Mine, DMS Struts to lift car 2in. Tyres Wrangler Silent Armor 235/70R16, PBR Radiator. 6 speed with DCCD and R180 rer diff, Heavy duty top strut mounts front and rear. Speedo correction box fitted. New stero (gave up on the old one). Back seat removed and 2 spare tyres fitted for desert driving. ECUTune SC sitting in the box for the next SVX. 1992 - SVX 255 K Wife (Want to stay Married so not allowed to fit SC) 1992 - SVX Pearl with black roof race car roll cauge etc ready to race. Ex Tasman Targa car. 1995 - SVX Green low k mint condiation. 1995 - SVX Rally car, ex Matts car. Now to be used on track. 1992 - SVX red & Black being converted to Mid Engine. 1995 - SVX Red 143,000 bit rough. Owned 5 others Subaru back to a 1974 1400 GSR. |
#24
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Re: Camshafts for the EG33.
I'm sure it is. My information as above came from Kelford though who mentioned they've got no issues running hydraulics to many rpms.
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#25
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Re: Camshafts for the EG33.
Something rather interesting, stock cam profiles from the cam place:
Intake: 4 thou: 247.24 duration 50 thou: 187.75 duration Lift: 7.1mm Exhaust: 4 thou: 255.33 duration 50 thou: 194.17 duration Lift: 7.9mm My friend also supplied the stock head flow to the cam place and they've suggest 272 / 272 with 9.5 mm lift and around 225-235 @ 50 thou IIRC. Shall be rather interesting - that shop can claim supplying a certain 1200 bhp with it's cams also... cough *310* duration.. 12-13mm lift so we already know they're capable... should be interesting. Last edited by bazza; 07-26-2012 at 06:37 PM. |
#26
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Re: Camshafts for the EG33.
This is the cam/valves used in the Ducati 1098’s 550 cylinder that I compared .to the EG33 before.
The EG33 550cc cylinder gets 38.3hp at 5600 , and 38 ft-lbs at 4800. The Ducati 550cc cylinder gets 58.5hp at 10,000, and 39 ft-lbs at 9500. ____________INLET__________EXHAUST. TIMING____O/C 11* 58*_____O/C 60* 20*@ 0.002" DURATION_____253____________260 LOBE CENT_____111.5___________110 LIFT__________11.8____________10.6 VALVE SIZE____41mm____________34mm You can see that they rely more on the valve size and lift to fill the cylinder, while keeping the duration and timing as low as they can, to provide the strong wide, useably torque curve, while still developing the HP that gives the speed. Harvey.
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One Arm Bloke. Tell it like it is! 95 Lsi. Bordeaux Pearl, Aust. RHD.149,000Kls Subaru BBS wheels. 97 Liberty GX Auto sedan. 320,000Kls. 04 Liberty 30R Auto Premium. 92.000kls. Last edited by oab_au; 07-26-2012 at 08:22 PM. |
#27
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Re: Camshafts for the EG33.
From my other thread:
EG33 spring height vs MY99+ spring height. EG33 using dual valve springs: Gutted hydraulic valve (EG33) vs MY00 style shim over bucket setup. Gutted to determine hydraulic height and valve height for "solid" bucket solution. MY99 is to short. MY98 is to long. Doh!! |
#28
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Re: Camshafts for the EG33.
Bazza,
FWIW, the advice I got (from a guy who worked with Cosworth motors for many years) is you'll be wanting to chase the lift...I can't remember exactly but stock coil bind is around 9mm...even with different grade springs, you might be able to get that higher but to what end? Solid buckets, shim under (not over) is really the way to go I think for reliable high revs. I realise people have had hydraulic buckets higher but is it worth it when valvetrain weight starts to become a factor. Interesting on the drag motor...glad you dug that up. 310 duration is decent...must have idled like a ***** and had a very narrow peak curve. The other thing worth considering is if you're doing a turbo build...a lot of the cam theory goes out the window in my experience. M |
#29
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Re: Camshafts for the EG33.
And I'm sorry you mapped the stock cams. I'd also had that done about 5 years ago. Could have provided you the numbers...and the stock head flows too!
M |
#30
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Re: Camshafts for the EG33.
Quote:
So we're going to run 8-9.5 mm lift with massive duration - LAN already has shown these to work and Kelford show in there charts that this can easily be done. Something else to note is you don't actually need more lift than that - the stock heads flow huge amounts to that lift however above that lift the heads don't really increase in flow (based on our flow figures) - HOWEVER this flow still supports 400 maybe even 500 kw ATW. So as you can see there aren't really any positives for us running lots of lift for the planned 300-400 kw atw. Above that yes. As for hydraulic buckets they're absolutely fine for my purpose. They'll do 6500-7000 rpm all day long: http://www.youtube.com/watch?v=qssbthwIb4s The only rule I stick with hydraulics is to use a SOFT RPM limiter only. A hard rpm limiter going off can pump the buckets up and you can lose compression in all cylinders for a few seconds.. BAD. Solids would be nice but given the "PITA" factor and the cost I'd only recommend them for a NA engine like Jack's or what Tony is planning on building. P.S. My mate wanted the heads and cams profiled to ensure we didn't make any mistakes - I believe his brand new billets arrive today Last edited by bazza; 07-31-2012 at 08:06 PM. |
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