Oil pressure vs volume
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Re: Oil pressure vs volume
[attachment=0]487660F6-78ED-4825-99B1-4F7C36AFE1A6.png[/attachment
Thanks to Kevin Johnson for sending me one of his screen assemblies. Just getting it fabbed in. I’ll get some pics when bolted in. Fit perfectly Kevin!!
Thanks to Kevin Johnson for sending me one of his screen assemblies. Just getting it fabbed in. I’ll get some pics when bolted in. Fit perfectly Kevin!!
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Re: Oil pressure vs volume
All in place with locks.
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Re: Oil pressure vs volume
Well borrowed some 1.8 crowers to double check lift. The 1.73 net .748int and .731 ex with zero lash. The 1.8 give .770 int. And .759. The cam is ground for .780 on both. The difference in both shows the difference in valve train geometry and likely difference in rockers themselves. . The bt heads are quite different. Has Anyone else seen this? Also opened up pushrod holes and the screen offered by Kevin. Still debating on cam and vac pump. Thanks.
Re: Oil pressure vs volume
Yes, large lift variation between rockers. Very good chart in D.Vizard's BBC book, where he tested different rockers with interesting results.
Re: Oil pressure vs volume
Geoff im getting variation between intake and exh with same rockers. Never seen that on other Cleveland heads before.
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Re: Oil pressure vs volume
Steve, are you saying that the same two rockers on different cylinders is giving different lift numbers ?? Please expand. Mark H.
Re: Oil pressure vs volume
Have you set the push rod and rocker geometry up correctly on both the intake and exhaust for these heads?
Paul
Re: Oil pressure vs volume
Yes. Verified lobe lift. Use same rocker on both valves and do everything identical the exh ends up close to .011 less lift every time. Switch to 1.8 rockers same result.The geometry for both intake and exh must be different somehow. I’ve had another guy tell me head has some unusual quirks. That must be what he was referring to.
Re: Oil pressure vs volume
G,day Steve,
Are you using a shaft or stud rocker? How are you setting up your geometry?
With stock heads i see different stand heights and different length push rods between intake and exhaust to get them set up correctly.
Advertised rocker ratios mean very little,
Those BT heads are an excellent head.
Paul
Are you using a shaft or stud rocker? How are you setting up your geometry?
With stock heads i see different stand heights and different length push rods between intake and exhaust to get them set up correctly.
Advertised rocker ratios mean very little,
Those BT heads are an excellent head.
Paul
Re: Oil pressure vs volume
Rockers are on studs yes. I like the head just this little quirk the i can see.
Re: Oil pressure vs volume
I’ve seen difference between intake and ex before with stock heads.
IMO with shaft rockers you have a better chance of getting your geometry correct by being able to change both stand height as well as pushrod length.
Bit of a compromise as you can see with a stud rocker
IMO with shaft rockers you have a better chance of getting your geometry correct by being able to change both stand height as well as pushrod length.
Bit of a compromise as you can see with a stud rocker
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Re: Oil pressure vs volume
Slightly tangental to the topic but perhaps useful nonetheless.
Recently viewed a x-y graph comparing oil pressure to engine speed across the full range while on track.
The irregularity of pressure trace was quite surprising. It showed oil pressure behavior never expected.
If your data logger can measure oil pressure, plot the pressure against rpm.
Add cornering and braking G forces in place of rpm.
Recently viewed a x-y graph comparing oil pressure to engine speed across the full range while on track.
The irregularity of pressure trace was quite surprising. It showed oil pressure behavior never expected.
If your data logger can measure oil pressure, plot the pressure against rpm.
Add cornering and braking G forces in place of rpm.
Re: Oil pressure vs volume
Schrick has a dyno that rotates in X and Y axes and can simulate g-forces on various road courses. Obviously limited to 1.0g. We data logged our circle track car and saw a high of 1.8-1.9g on a super late model, depending on tires and setup.