Who made your pistons?
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Timo wrote:
>
> No 10:1 on pump gas? I run 10.5:1 on 93 octane

 

I also run over 10:1 in my 350 Chev. This is a true blueprinted 10.6
compression ratio on 92 octane. Everything was CCed. It is not the norm to
be able to do this however. My combustion chambers are polished to an almost
mirror finish, and all sharp edges are removed from the piston tops. I also
have aluminum heads which is usually good for a half a point of compression
or so. They are more resistant to pinging because they draw more heat from
the combustion chamber. A bigger cam also lets you get away with a little
more compression. I also played around a lot with timing. My truck is light
(S10) and has 3.70 gears with 26.5" tires and a 3.06 first gear, so there
isn't as much load on the engine as there would be in a full size truck. I
wouldn't recommend running much over 9:1 for most 4wd applications on pump
gas though.

Chris


"Timo" <tfischer@sympatico.ca> wrote in message
news:kPN0c.2981$i_2.32328@news20.bellglobal.com...
> No 10:1 on pump gas? I run 10.5:1 on 93 octane
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:40429740.7810EA14@***.net...
> > Yup, just like the '64 Rambler engine. 270 degrees is the stock
> > grind for the TJ's 4.0 liter. Anything more than nine to one will not
> > run on today's pump gas. Thank God for leaded aviation fuel.
> > God Bless America, ßill O|||||||O
> > mailto:-------------------- http://www.----------.com/
> >
> > Drink wrote:
> > >
> > > I'm in Florida. So, there's no inspection. I don't intend to rely
on
> > > (0-throttle) idle to navigate obstacles since we don't have rocks in
> north
> > > FL:)
> > > Bill, you say that a 290deg cam will idle at 600-700RPM and I'm sure
> it
> > > will. My concern's that the Clifford site lists multiple
> > > requirements/preferences for that grind, i.e. aftermarket springs to
> prevent
> > > binding, 650cfm 4Bbl, 10:1 compression pistons, 4.0 head conversion,
> etc.
> > > All in all, a full race cam. I think I'm leaning toward the 272deg
cam
> but
> > > what do you think about a 280deg cam with Rhoades lifters to retard it
a
> bit
> > > at idle?
> > > Anybody have any experience with Rhoades lifters? How's this setup
> sound?
> > > o_o_o_o
> > > Best Regards, /| ,[_____],
> > > Jim, WP3JQ |¯¯¯L --O|||||||O-
> > > ()_)¯()_) ¯¯¯¯¯ )_)
> > > EM60qk 30.447439N 086.628959W
> > > "CRWLR" <CRWLRJEFF@YAHOO.COM> wrote in message
> > > news:1044r8q1getmrf5@corp.supernews.com...
>
>

 

I also run over 10:1 in my 350 Chev. This is a true blueprinted 10.6
compression ratio on 92 octane. Everything was CCed. It is not the norm to
be able to do this however. My combustion chambers are polished to an almost
mirror finish, and all sharp edges are removed from the piston tops. I also
have aluminum heads which is usually good for a half a point of compression
or so. They are more resistant to pinging because they draw more heat from
the combustion chamber. A bigger cam also lets you get away with a little
more compression. I also played around a lot with timing. My truck is light
(S10) and has 3.70 gears with 26.5" tires and a 3.06 first gear, so there
isn't as much load on the engine as there would be in a full size truck. I
wouldn't recommend running much over 9:1 for most 4wd applications on pump
gas though.

Chris


"Timo" <tfischer@sympatico.ca> wrote in message
news:kPN0c.2981$i_2.32328@news20.bellglobal.com...
> No 10:1 on pump gas? I run 10.5:1 on 93 octane
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:40429740.7810EA14@***.net...
> > Yup, just like the '64 Rambler engine. 270 degrees is the stock
> > grind for the TJ's 4.0 liter. Anything more than nine to one will not
> > run on today's pump gas. Thank God for leaded aviation fuel.
> > God Bless America, ßill O|||||||O
> > mailto:-------------------- http://www.----------.com/
> >
> > Drink wrote:
> > >
> > > I'm in Florida. So, there's no inspection. I don't intend to rely
on
> > > (0-throttle) idle to navigate obstacles since we don't have rocks in
> north
> > > FL:)
> > > Bill, you say that a 290deg cam will idle at 600-700RPM and I'm sure
> it
> > > will. My concern's that the Clifford site lists multiple
> > > requirements/preferences for that grind, i.e. aftermarket springs to
> prevent
> > > binding, 650cfm 4Bbl, 10:1 compression pistons, 4.0 head conversion,
> etc.
> > > All in all, a full race cam. I think I'm leaning toward the 272deg
cam
> but
> > > what do you think about a 280deg cam with Rhoades lifters to retard it
a
> bit
> > > at idle?
> > > Anybody have any experience with Rhoades lifters? How's this setup
> sound?
> > > o_o_o_o
> > > Best Regards, /| ,[_____],
> > > Jim, WP3JQ |¯¯¯L --O|||||||O-
> > > ()_)¯()_) ¯¯¯¯¯ )_)
> > > EM60qk 30.447439N 086.628959W
> > > "CRWLR" <CRWLRJEFF@YAHOO.COM> wrote in message
> > > news:1044r8q1getmrf5@corp.supernews.com...
>
>

 

I also run over 10:1 in my 350 Chev. This is a true blueprinted 10.6
compression ratio on 92 octane. Everything was CCed. It is not the norm to
be able to do this however. My combustion chambers are polished to an almost
mirror finish, and all sharp edges are removed from the piston tops. I also
have aluminum heads which is usually good for a half a point of compression
or so. They are more resistant to pinging because they draw more heat from
the combustion chamber. A bigger cam also lets you get away with a little
more compression. I also played around a lot with timing. My truck is light
(S10) and has 3.70 gears with 26.5" tires and a 3.06 first gear, so there
isn't as much load on the engine as there would be in a full size truck. I
wouldn't recommend running much over 9:1 for most 4wd applications on pump
gas though.

Chris


"Timo" <tfischer@sympatico.ca> wrote in message
news:kPN0c.2981$i_2.32328@news20.bellglobal.com...
> No 10:1 on pump gas? I run 10.5:1 on 93 octane
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:40429740.7810EA14@***.net...
> > Yup, just like the '64 Rambler engine. 270 degrees is the stock
> > grind for the TJ's 4.0 liter. Anything more than nine to one will not
> > run on today's pump gas. Thank God for leaded aviation fuel.
> > God Bless America, ßill O|||||||O
> > mailto:-------------------- http://www.----------.com/
> >
> > Drink wrote:
> > >
> > > I'm in Florida. So, there's no inspection. I don't intend to rely
on
> > > (0-throttle) idle to navigate obstacles since we don't have rocks in
> north
> > > FL:)
> > > Bill, you say that a 290deg cam will idle at 600-700RPM and I'm sure
> it
> > > will. My concern's that the Clifford site lists multiple
> > > requirements/preferences for that grind, i.e. aftermarket springs to
> prevent
> > > binding, 650cfm 4Bbl, 10:1 compression pistons, 4.0 head conversion,
> etc.
> > > All in all, a full race cam. I think I'm leaning toward the 272deg
cam
> but
> > > what do you think about a 280deg cam with Rhoades lifters to retard it
a
> bit
> > > at idle?
> > > Anybody have any experience with Rhoades lifters? How's this setup
> sound?
> > > o_o_o_o
> > > Best Regards, /| ,[_____],
> > > Jim, WP3JQ |¯¯¯L --O|||||||O-
> > > ()_)¯()_) ¯¯¯¯¯ )_)
> > > EM60qk 30.447439N 086.628959W
> > > "CRWLR" <CRWLRJEFF@YAHOO.COM> wrote in message
> > > news:1044r8q1getmrf5@corp.supernews.com...
>
>