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NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
rough block measurements
Posted by: NixVegaGT
Date: January 26, 2010 08:14PM

Hey team. I've finally gotten a bit of time to measure stuff on the Rover blocks I just picked up from Tidewater in NC. First things first, these blocks are in really great shape. No signs of liner slipping or cylinder scoring. WOW! Ok on to the measurements:

Front cam journal dia. (w/o bearing): 1.920"
Main journal dia. (w/o bearing): 2.666"

Crank/Cam center to center: 4.325"

Sleeve length: 5.375"

Deckheight: 8.975" (that seems high but I measured it a bunch of times)
Distance between the inside block skirt: 7 3/4".
Outside width of the cylinder banks (across the centerline of the cylinders): ≈ 5 1/4"

I know there's a bunch of documentation on this but the bore centers are indeed 4.24". LOL! Ok so with 4.5" it's pretty tight to the cylinder head bosses and potentially narrow inside the water jackets between the outside block and the sleeve. The distance between the 4.5" weld-in bore and the ID of the head bolt holes is about 0.175". That looks to be just about the wall thickness of the head bolt bosses inside the casting. The bosses get smaller in dia. after the threaded portion and goes all the way through the block. It looks like the flow of water will be, obviously, more restricted. I wonder if this is an issue however. Any opinions?

Do those measurements square? Does anything look way off?

Does anybody know if the crank/cam center distance is the same for all SBB's? It looks like there is room for the mega stroke using the "Honda" journal but at this point it's all mathmatical. I'm sure with practical tests I'll have a clearer answer. While I was measuring I did notice one of the mains is pretty badly damaged. Can this be fixed with TIG??



Edited 1 time(s). Last edit at 01/26/2010 08:24PM by NixVegaGT.


mgb260
Jim Nichols
Sequim,WA
(2463 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: rough block measurements
Posted by: mgb260
Date: January 27, 2010 02:36AM

Nic, Instead of 4.5" O.D. aluminum, you can get 4.24" O.D. at the onlinemetalstore. Schedule 10 4" aluminum 6061(T6) .120" wall pipe.Then hone/bore to 4.097" for .003" interference fit for the tractor liners(4.1 O.D.)Roverman... please check for typos,thanks again.



Edited 2 time(s). Last edit at 01/27/2010 04:43AM by mgb260.


pcmenten
Paul Menten

(242 posts)

Registered:
10/08/2009 10:40AM

Main British Car:


Re: rough block measurements
Posted by: pcmenten
Date: January 27, 2010 03:13AM

Nic, is there a paint mark on the inside of the lifter valley walls? What are they, blue, yellow, red? Or, perhaps a number written in there? The 4.6 blocks were sorted out from the 4.0 by cylinder wall thickness.

Too bad about the bunged main journal. Time to bore it for a 300 crank?


NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
Re: rough block measurements
Posted by: NixVegaGT
Date: January 27, 2010 07:45AM

The other block is perfect. I'm not seeing any paint marks on either block so I'm betting they are just standard 4.0. I didn't notice the massive chamfer at the top of the sleeves last time I did this but it was a few years ago. The bores look tiny. LOL! I can't remember how small the 3.5" bores looked like now. Well this morning I meet with the machine shop about boring out the blocks to remove the cast liners.

I'm not sure the main can be fixed. It's pretty bad on the one block. I'll find out today.


roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: rough block measurements/precision please?
Posted by: roverman
Date: January 27, 2010 11:04AM

Nic', "bunged rear main bore"? Sounds like a "natural" for a 340/350 sbb. crank? 2.75" mains,(427 Ford)? ALL 215-350sbb's are same for cam-crank c/l's. Consider sbc. cam drive in gear,(lengthened twin idler bar), or belt,(VCD.)? Since 4.25" od. alum. would effectively be "symesed", what's to gain vs larger with flange ? Deck dim. sounds high. Calipers right ? They have to be absolutely "square". Make sure your "factoring" the correct main bore dim. I hope (1) of these will have, "bunch-o-cams" on top?Good Luck. Your going to share with "MIKE"-right? FWIW, I just ordered (2) "tractor" sleeves. Should make good torque right? lol, roverman.



Edited 2 time(s). Last edit at 01/27/2010 04:10PM by roverman.


NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
Re: rough block measurements/precision please?
Posted by: NixVegaGT
Date: January 27, 2010 06:20PM

Great info, Art. So you got a couple of those Ford 3.9" bore sleeves coming to you? Let me know some more detailed dimensions when you get a chance. There's not much info on those websites. Thanks man!

I like the sound of using the 350 main dia. It will probably weaken the main cap but I could use a bottom girdle. That may be a good idea either way with the long stroke 350 crank. If I use the tractor sleeve with this crank I really should use the probe 1.05" height 3.902" piston and the 6" Honda rod with a slight destroke on the crank (3.8"). That makes a sorta boring 6.0L. Been done. Well the size anyway. I'm sorta tempted to go out to 4.06" for a full 400 cid. I'll have to do some experimentation to do that. Maybe let a couple cats outta the bag when the time comes. I'd use Probe's PRS 1" height 4.06" pistons with the Honda 6" rod and as much stroke as I can get without it hitting the cam or block. I'd only need an extra 20 thou of stroke to break the magic 400 barrier. Now that would be wicked.

I'm planning on sharing everything including all my failures too. I think it helps strengthen the community. The blocks are being chewed out this week. I'll have the water jacket dims shortly after that.

I suppose I could be off on the squareness with the main bore and the deck. It is pretty hard to measure with calipers. Ha ha. Ya know what it might be is I had the caliper on far enough that it engaged the wider portion of the caliper jaw. That would account for some extra length.


roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: rough block measurements/427 mains
Posted by: roverman
Date: January 27, 2010 08:06PM

Nic, I know it's a little more work, but using Ford 427 mains will leave the caps and block stronger and with less bearing speed. I'm not sure if 340/350sbb;s have "wider" CL's on main cap bolts. Bet Jim B. could figure ? roverman.



NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
Re: rough block measurements/427 mains
Posted by: NixVegaGT
Date: January 28, 2010 07:34AM

Do you mean literally using the FE main caps? Or something that looks like them.


roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: rough block measurements
Posted by: roverman
Date: January 28, 2010 10:59AM

Nic, actually you would bore Rover block/caps approx .25" instead of .5". Not a lot of different main bearings for 2.75".One would need to "narrow" #3. roverman.


NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
Re: rough block measurements
Posted by: NixVegaGT
Date: January 28, 2010 03:04PM

Right. Got it. The 350/340 mains are 3". That's right. Thanks man! I'm sure 3" just wouldn't happen. 2.875" looks to be about 100 thou from the bolts. I think we'll be in good shape though. I'll let you know.


NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
Re: rough block measurements
Posted by: NixVegaGT
Date: January 28, 2010 10:08PM

Sorry Jim. I never answered your post about the 4.25" OD tube. I guess I'd feel more comfortable going a bit larger and turning it down to something more like 4.35". That leaves me with 125 thou of wall thickness for the aluminum bores. I think the cast bores have about that, right? Or is it 120 thou. Anyway it's close. I suppose I could leave some around the top like a "flange" too.It would give me more margin for the iron sleeve's flange to fit into. Might not be necessary...


mgb260
Jim Nichols
Sequim,WA
(2463 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: rough block measurements
Posted by: mgb260
Date: January 29, 2010 12:55PM

I was thinking, with the flange on the liner, the thinner aluminum would go between the flange on the tractor liner and the lower block with just the cast iron liner going through the lower block.Kind of like the stepped Caddy liner,everything interference fit. You could heat the aluminum with a radiant quartz heater and freeze the iron liners. Use a stepped aluminum mandrel and dead blow hammer to pound/slip together. Then use the heater on the block and refreeze the combined sleeves and pound/slip into block. It will make a ringing noise when seated. I would use an old head gasket and torque down to make sure all are evenly seated. You should figure .003 for interference fit for aluminum to liner and liner to block.Plus, a couple of thousand for liner to protrude above block. Like Roverman said, the 4.24 would touch anyway, anything thicker would have to have flats milled. Maybe I stumbled on Mike's secret method.The dead blow hammer/heating/freezing is how you install "tractor" liners.



Edited 4 time(s). Last edit at 01/31/2010 02:03PM by mgb260.


NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
Re: rough block measurements
Posted by: NixVegaGT
Date: January 29, 2010 03:15PM

Ok. I think I get what you're saying so it clamps the upper flange better by running it through to the bottom.

We are sorta on the same page. I was thinking I'd install he T6 bores into the water jacket area from the deck to the lower part of the block. Weld them at the siamese, deck and, if possible, to the lower block right at the bottom of the water jacket. Then bore out the hole and press the tractor liner in. The thing is I was thinking the walls of the aluminum bores would need to be thicker.

You may have already gotten that from my ambiguous posts, I'm sorry if it was obvious but just for the sake of documenting the conceptualization phase.

Thanks for the input, Jim. That pic of the deck plate is SUPER descriptive. Thanks for that.


roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: rough block measurements
Posted by: roverman
Date: January 29, 2010 05:31PM

Who's to say we can't make the "underside" of deck plate, "like" a MID liner, ie. coolant channel with transfer holes through orig. deck and head ? I definately like welding,"All" alum. first , then finish boring for installation of cast sleeves ,last. roverman.


mgb260
Jim Nichols
Sequim,WA
(2463 posts)

Registered:
02/29/2008 08:29PM

Main British Car:
1973 MGB roadster 260 Ford V8

Re: rough block measurements
Posted by: mgb260
Date: January 29, 2010 06:31PM

My idea was no welding, just pressing/interference fit.



roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: rough block measurements/sleeve-no seive
Posted by: roverman
Date: January 29, 2010 08:20PM

Well clan, It appears, " a very warm place will freeze-over", before "Mike" spills beans! Jim, yes it would be simpler if press fit was all that was needed to hold the "skeleton" together. I don't think it would be. While tig is more trouble, if the method proves worthy, then it's worth it. I'm told, "furnace brazing' will need to be close to alum. melt temp, not good. This latest procedure appears mostly, labor intensive , with sleeves and liners being cheap. roverman.


NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
Re: rough block measurements/sleeve-no seive
Posted by: NixVegaGT
Date: January 30, 2010 11:16AM

Yeah. That's the only reason I'm looking into it. I can afford the time it takes. I'm not trying to sell the idea or make a bunch of them. It's really just a hobby. Hobbies need time spent on them. Fringe benefit is a big motor at the end! LOL.

One thing that is definitely less expensive is the cylinder liners. $30 beats the @#$%& outa $60 or more ea. Still gotta pay to have somebody do the block setup. I'm really not set up for that: Decking, boring, pressing. I can weld though and that's the labor intensive part.


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