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buguy Samba Member
Joined: November 17, 2003 Posts: 4915 Location: Port Orange, FL
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Posted: Wed Apr 01, 2020 7:18 am Post subject: Advancing the cam |
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So since my clutch disk broke and I'm waiting for the new one to arrive I've been thinking. I put too big of a cam in my turbo engine. I advanced it 2 degrees when I installed it and I was wondering if I went another 2 degrees would it be worth all the work of tearing the engine down. I put it in hoping to spin it to 6500 rpm but it won't make power past 6000. Must be the stock heads holding me back
Anyway, what would I gain by advancing it 2 more degrees?
Stock 1600 engine with a Web 163. EFI, turbo, infercooler, and E85 on 30 psi
Of boost. |
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Nightshift Samba Member
Joined: December 31, 2019 Posts: 222
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Posted: Wed Apr 01, 2020 7:26 am Post subject: Re: Advancing the cam |
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What is the LSA on the cam you have? Did you degree the cam when you put it in. If so where does it stand? |
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buguy Samba Member
Joined: November 17, 2003 Posts: 4915 Location: Port Orange, FL
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Posted: Wed Apr 01, 2020 7:34 am Post subject: Re: Advancing the cam |
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It's on a 112 and no I didn't degree it. |
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risk Samba Member
Joined: June 24, 2004 Posts: 710 Location: Stumpbroke, Arkansas
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Posted: Wed Apr 01, 2020 7:40 am Post subject: Re: Advancing the cam |
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Could be valvetrain float.. what springs are you running? |
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jason Samba Member
Joined: August 07, 2002 Posts: 3444 Location: Garage
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Posted: Wed Apr 01, 2020 7:51 am Post subject: Re: Advancing the cam |
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You can advance or retard it with the oil pump removed. Saying its advanced without checking it doesnt make it so, could be a few degrees off. |
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buguy Samba Member
Joined: November 17, 2003 Posts: 4915 Location: Port Orange, FL
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Posted: Wed Apr 01, 2020 7:52 am Post subject: Re: Advancing the cam |
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Definitely valve float. Single HD springs and 30 psi doesn't work. |
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buguy Samba Member
Joined: November 17, 2003 Posts: 4915 Location: Port Orange, FL
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Posted: Wed Apr 01, 2020 7:57 am Post subject: Re: Advancing the cam |
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jason wrote: |
You can advance or retard it with the oil pump removed. Saying its advanced without checking it doesnt make it so, could be a few degrees off. |
Agreed. But from what I've read the Web cams have been pretty good. |
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buguy Samba Member
Joined: November 17, 2003 Posts: 4915 Location: Port Orange, FL
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Posted: Wed Apr 01, 2020 8:04 am Post subject: Re: Advancing the cam |
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I'm not sure I can do mine through the oil pump. I have the washer type and they weren't easy to get in the holes when the cam was out. It's a CB gear.
I just don't want to go to the trouble if it's only going to gain me like 100 rpm lower end of that makes sense. |
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74 Thing Samba Member
Joined: September 02, 2004 Posts: 7389
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Posted: Wed Apr 01, 2020 8:28 am Post subject: Re: Advancing the cam |
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How about some beehive springs in your heads instead of the HD singles?
What HD singles did you use and did you shim them up to approx .050" from coil bind? |
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Nightshift Samba Member
Joined: December 31, 2019 Posts: 222
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Posted: Wed Apr 01, 2020 8:34 am Post subject: Re: Advancing the cam |
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buguy wrote: |
jason wrote: |
You can advance or retard it with the oil pump removed. Saying its advanced without checking it doesnt make it so, could be a few degrees off. |
Agreed. But from what I've read the Web cams have been pretty good. |
To install a cam without setting correctly will not help you. Its like trying to hit the dart board in the dark. |
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Stripped66 Samba Member
Joined: May 31, 2005 Posts: 3470 Location: Charleston, SC
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Posted: Wed Apr 01, 2020 8:39 am Post subject: Re: Advancing the cam |
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Advancing the cam timing shifts the HP/torque curve to a lower RPM range. _________________
66brm wrote: |
Bodacious wrote: |
Why not just make a custom set of wires with a Y splice in them. Then you could just run one distributor. |
I don't think electrickery works that way |
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Nightshift Samba Member
Joined: December 31, 2019 Posts: 222
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Posted: Wed Apr 01, 2020 8:47 am Post subject: Re: Advancing the cam |
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74 Thing wrote: |
How about some beehive springs in your heads instead of the HD singles?
What HD singles did you use and did you shim them up to approx .050" from coil bind? |
I have ordered a set of beehive springs and retainers. As always to people setting up springs, just don,t throw them in and expect them to work. spring bind and seat pressures must be accurate. If you are to heavy over the nose you have the wrong spring. |
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Nightshift Samba Member
Joined: December 31, 2019 Posts: 222
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Posted: Wed Apr 01, 2020 9:07 am Post subject: Re: Advancing the cam |
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buguy wrote: |
Definitely valve float. Single HD springs and 30 psi doesn't
work. |
We need to know your valve area(square inches) - the stem diameter to figure in your calculated spring pressure needed.
rule of thumb 30PSI X area = additional pressure
This is just a rue of thumb.
Last edited by Nightshift on Wed Apr 01, 2020 9:31 am; edited 1 time in total |
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buguy Samba Member
Joined: November 17, 2003 Posts: 4915 Location: Port Orange, FL
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Posted: Wed Apr 01, 2020 9:20 am Post subject: Re: Advancing the cam |
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I don't remember what springs they are I bought them in 2007! But I don't think I will be putting any money into these. They have whatever stock valves are. Certainly they need a valve job. Guides didn't feel too bad though. I did some home porting and a little smoothing in the chamber. These heads just aren't going to ever be what I need, so I'm just trying to do what I can with what I have. |
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buguy Samba Member
Joined: November 17, 2003 Posts: 4915 Location: Port Orange, FL
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Posted: Wed Apr 01, 2020 9:28 am Post subject: Re: Advancing the cam |
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Stripped66 wrote: |
Advancing the cam timing shifts the HP/torque curve to a lower RPM range. |
Yes.... But by how much?! Is there a rule of thumb? |
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halfassleatherworks Samba Member
Joined: December 09, 2018 Posts: 641 Location: Reno NV
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Posted: Wed Apr 01, 2020 9:40 am Post subject: Re: Advancing the cam |
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only 200-300 rpm. it does not change the cam characteristics just moves it a little n the RPM. to increase your max RPM you need a cam profile that will run that high. _________________ Halfass Leatherworks*****GOT LEATHER Made to order Leather crafts, you can find us on that face book thing
Belts, wallets, mouse pads, drink coasters, Engraving, most things made in leather.
personal items if you want it in leather in Reno Nv, ***** |
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Nightshift Samba Member
Joined: December 31, 2019 Posts: 222
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Posted: Wed Apr 01, 2020 9:40 am Post subject: Re: Advancing the cam |
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buguy wrote: |
Stripped66 wrote: |
Advancing the cam timing shifts the HP/torque curve to a lower RPM range. |
Yes.... But by how much?! Is there a rule of thumb? |
You must have a starting point. To advance or retard the cam you will need to set up a degree wheel and a dial gauge and will need to know exactly where TDC is not just the timing mark on the pulley. if you are going to this much trouble. Degree the cam correctly, take it for a ride and see how preforms. Keep an eye on your boost as it will tell you a lot. |
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Stripped66 Samba Member
Joined: May 31, 2005 Posts: 3470 Location: Charleston, SC
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Posted: Wed Apr 01, 2020 9:44 am Post subject: Re: Advancing the cam |
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buguy wrote: |
Stripped66 wrote: |
Advancing the cam timing shifts the HP/torque curve to a lower RPM range. |
Yes.... But by how much?! Is there a rule of thumb? |
The 163 is the Web equivalent of an Engle 110. Its advertised powerband is ~1500-5500 rpm. It doesn't care what the displacement is. So, by originally installing the cam advanced, you shifted that powerband to an even lower RPM range, and you're wondering why you're not making power above 6000 rpm.
And you were expecting power to 6500 rpm?
I won't opine on your valve spring situation. It may be related to your power dropping off above 6000 rpm; but, the obvious issue is your cam install. _________________
66brm wrote: |
Bodacious wrote: |
Why not just make a custom set of wires with a Y splice in them. Then you could just run one distributor. |
I don't think electrickery works that way |
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buguy Samba Member
Joined: November 17, 2003 Posts: 4915 Location: Port Orange, FL
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Posted: Wed Apr 01, 2020 9:51 am Post subject: Re: Advancing the cam |
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The 163 is advertised as a 6500 rpm cam. And generally a turbo will add 1000 rpm on top of that. Figured advancing it 2 degrees might drop it 500 rpm.
But I figured since I'm not getting the rpms I want I may as well advance it and get the low end I lost back. |
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Stripped66 Samba Member
Joined: May 31, 2005 Posts: 3470 Location: Charleston, SC
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Posted: Wed Apr 01, 2020 9:53 am Post subject: Re: Advancing the cam |
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buguy wrote: |
The 163 is advertised as a 6500 rpm cam. And generally a turbo will add 1000 rpm on top of that. |
Nope and nope. _________________
66brm wrote: |
Bodacious wrote: |
Why not just make a custom set of wires with a Y splice in them. Then you could just run one distributor. |
I don't think electrickery works that way |
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