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  1. #1
    Join Date
    Sep 2003
    Sonora, California, United States.

    Stroking the RV8 in the States

    This is my first post to this forum, and it appears to be the best place to ask questions about the RV8. There are not very many experts on Rovers in the States.
    I am in the process of building a stroked engine. I have aquired a 1996 4.0 engine, had it bore aligned ~.022 to accept the Buick 300 crank and bearings. Cylinders have been honed .010 over for the use of Ford 255 pistons with standard 3.5 connecting rods. Heads are p/p Buick 300 with 54cc combustion chambers. Calculated compression will be ~10.00 to 10.8 with a metal gasket. What will the compression be if a composite gasket is used. (looking for 9.0 to 9.5) Second, is there a list of breakers who are willing to ship to the States for those hard to find bits?

    No Cobra yet, but looking at a Hawk 1.8 for the RV8


  2. #2
    Join Date
    Apr 2004
    East Leake, Nottinghamshire, England.

    RE: Stroking the RV8 in the States

    Hi Klatka, Russ is the expert on RV8 so hopefully he will pick up on this thread. As far as using the composite gasket goes I read on a previous post by Russ that it will cost 0.75 ie, 10.8 - 10.05. I think I am right in saying that if you go this route you should also use the later stretch head bolt fitted to later engines.
    If you are having problems getting spares over there, there is a company which will supply you new parts, and ship them anywhere called Rimmer Bros got most of my bits from there and they are quite reasonably priced.

    Best of luck and I hope this is of some help.

    Martin :tu :tu :tu :tu

    351W 416.7 HP and 466.8 ft-lbs

    Running Mega Squirt and Edis 8

  3. #3
    Join Date
    May 2003
    High Wycombe, Bucks, UK.

    RE: Stroking the RV8 in the States

    Contrary Mary

    As Martin says Russell is your man on this subject, I think 3/4 of a ratio is about right. I tryed metal gasket on my 3.9 which was 10.5 CR and it blew every one I fitted Eric.

  4. #4
    russell_ram Guest

    RE: Stroking the RV8 in the States


    Been doing a few sums on your question - so here goes.

    Buick 300 crank has a stroke of 3.4inch.
    Std 3.9/4.0/4.6 bore is 3.7 + your .010 over bore. = 3.710 inch.

    Engine capacity 4818cc.

    Buick 300 heads have 54cc combustion volume (as you say) compared to 36cc for std Rover heads.

    Tin gasket compressed volume (94mm bore) = 3.524cc
    Composite gasket compressed volume (94mm bore) = 8.105cc

    Comprssion ratio is governed on most RV8 engines by piston bowl volume typically 15 to 25cc dependant on derivative. I assume your Ford pistons are however, flat top which with your heads, engine volume and tin gasket gives 11.47:1. With composite gasket, the same sum gives 10.7:1. To get down to your desired 9.5 you either need the pistons not to reach the top of the bores or a bowl/dish in the piston to increase compressed combustion volume. You need approximately a piston bowl volume of 8.5cc to get 9.5:1 or 13.5cc to get 9.0:1. Alternatively, with flat top pistons they need to be 'down the bore' at TDC by 48 thou to get 9.5CR or 76thou to get 9.0CR.

    Hope that helps.


  5. #5
    Join Date
    Feb 2004
    Stoke On Trent.

    RE: Stroking the RV8 in the States

    Well you took the words right out of my mouth.

    I feel like a dumbo on earth do you manage to work all that out. Took me long enough to work out how much petrol to put in the tank.


  6. #6
    russell_ram Guest

    RE: Stroking the RV8 in the States


    Sorry I didn't let you answer first then!!!

    Perhaps I is gud at sums?


    ps When it says E, then that is the time to put some in. .Quite often in a Cob actually.

  7. #7
    Join Date
    Sep 2003
    Sonora, California, United States.

    RE: Stroking the RV8 in the States

    Thanks for the sums, this will give some direction when I go shopping for pistons. If needs be I can get them machined down to achieve the proper C/R.

    Thanks to all for their responses.


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