BritishV8 Forum

Sbf, I do belive. This aids in using the sbf raw forgings for sbb/rover cranks.  roverman.

John C. You "might" want to grind a junker 340/350,(3.7" stroke) sbb crank to a Honda journal size, to check your block clearance issues ? As I think about this, you could easily "fab" a plastic/alum. dummy/ partial crank,(2 mains,2 rod's), just for clearance checking. Rover's are narrower at the pan rail than sbb's.  Good Luck, roverman.

Don't know about pan rail clearance but cam lobe clearance is the usual issue. It gets real tight with aftermarket rods.

Jim

Jim and clan, Your speaking of 3.850" stroke with 2.0" rod journals ? Not a good option for Rover V8. As we have seen, 300 block is better suited for this much stroke. I suspect even a 3.7" stroke with a 2" journal will "bang" a rover block. Most folks springing for a forged custom crank, will want lot's of rev. potential. BadAssed torque is 455 territory.  Onward, roverman.

Art, in UK Rob Robertson at V8D built 5.5 RV8 with a stroke of 3.7" for a bore of 3.8" with 5.7" small journal SBC rods. Crank is full counterweight cast and can rev happy to 6500RPM. Cheers.

A Buick 350 crank won't "bang" a P76 block.  Well, not so much with stock Buick rods anyway...



Greg

Greg, Bravo !  Appears to have same pan width as regular rover ? What are the mains sized at ?

P76 main bearing size is actually 2.5495" .

Yes same pan width as regular rover.

STD P76 rods are decent forgings, too....Good for 6500 in road use...A shot peen & some ARP bolts wouldn't hurt, either.

Do you have a 4.0/4.6 block to try that crank in? 3.7 bore + 3.850 stroke would give 5.4L??

John, too many tangients already. Not a good swap IMHO. 3" mains down to 2.5" ? Deck way too short, piston skirts will bang counterweights. Poor rod ratio/etc. 300 iron block is better suited. Just ask Jim B., our resident task master of sbb;s. Onward, roverman.

Crower can produce a custom billet RV8 crank but 12 to 14 week delivery.

Someone mentioned Laystall cranks, they are somehow amalgamated with Allen Crankshafts Ltd. So they can still be obtained.

Art - Any word from Scat? I'm beginning to wonder if there's enough meat on the Rover crank to make a light weight crank like they do. Not like chunky Chevy/Ford cranks.

Upward.

Julian

Really, I suppose you could do that, (3.7 bore/3.85 stroke) if you were going for a light weight 5.4L engine. A bit undersquare and the block isn't all that strong and has other issues as well. But, with the right rods and slipper skirt pistons it could be done I expect. The real question is, how much is 80 lbs worth to you? Because what it will buy you (300 iron block) is a block that can handle well over 700 hp, has no liner issues, has much stronger threads and needs no thread inserts, has a larger bore already, and will easily give you a 5.7L displacement with an almost perfectly square bore and stroke (3.80 x 3.85). Then there is the whole issue about pulling the piston so far out of the bottom of the bore. May not be a problem but may also increase wear.

The MGB won't notice the weight difference, are you really confident you will? Because it will cost you money, engine life, and displacement. All of which I have a really hard time with giving up. As for bragging rights, have you noticed the subtle shift towards iron block engines? It still isn't much but we're seeing more and more SBFs and V6s. I have to think a lot of the reason is reliability, and this is the same reason I've gone to the iron block SBB. Some of us saw that trend coming and the only thing I know of that can slow it down is a new aluminum engine. Won't be the LS, too big. The 1UZ might stand a chance though, if it will fit. Now there's an engine with potential. Otherwise we're looking at the modern 4 cylinders and how much traction is one of those swaps going to get in the face of the V8 traditions?

Jim

Julian, Rover crank got sent to Scat, 3/12/12. I also spoke with them yasterday. They would start with the "chunky" sbf forging, if it is to happen. I'm apprehensive about lightening a cast rover crank,"maybe" pendulum cut the counterweights for a maximum cast effort. IMHO, their just not suited for serious, continous racing ventures. Onward, roverman.

Art - Was it a long nose crank you sent? Also could I have the name of your contact? I'm dealing with Alex Gonzales.

Julian

Long nose. Alex is the guy.

I just called Scat, to follow-up. They have the Rover 4.6L crank I sent. Tom is working on the project. Word is call back in 4-6 weeks.  Cheers, roverman.

Well "Aussie John".  You asked about a Buick 350 crank in a Rover block.  You got it!  This is what it looks like.  Forget the date on the pic.  I just took this an hour ago. The main size was cut to 2.5495" (P76 size) so I took out the bearings, greased up the mains and dropped it in.  It rotates freely.  Hits nothing.  As to what rods you'd use.... I have no idea...

You did ask...

Greg

I had to dig through my mucky garage to ferret this stuff out....  

Greg

Thanks Greg, Can't help but wonder if rods may hit oil port in block, etc. It looks like your also into Mopars and a Hemi ? You know Greg, a Jensen Healey will swallow a Hemi - no problem, jus' sayin. Onward, roverman.

Yeah, I'd have thought a 350 crank in a Rover block would have been done long ago.

Jim

Now that's an encouraging sight, Greg!! Do you have  a P76 or Rover rod & piston handy? It one could be attached to the crank, cam slipped in and the whole assembly rotated for the clearance check.

There would be alternative ways of getting oil to the pump if the internal gallery is the primary issue.

Jim B is correct in his view that a 300 block would be a better option in most cases.

In my part of the world, registration authorities & insurance companies make life difficult when alloy engine blocks get swapped for cast iron...Dont ask me why.....

I'm still trying to get my Bryant crank photos to load, as well.....

Cheers

John

These are old pics.  This is the same crank in a P76 block but with a stock 73-80 Buick 350 rod and some piston I dug up that fits the bore.  With this long rod, the capscrew just kisses the oil galley.  On a P76 block, no problem to grind a bit of relief for clearance.  No problems with the cam as well.  Rod angle is the same as the 350 so no worries.  The Rover block would get real interesting in there.  But... I would say if hot rodders have already figured out how to use the stock 300 rod on this crank, would it be that tough to have a custom piston fabbed up to use?   Also, the 75-77 Buick 3.8 odd fire rod is the same length as the Buick 300 rod but is shaped like the later 350 rod.

Some years ago I had a phone conversation with John Harcourt about the 350 crank in a P76 block.  He told me a friend of his had actually done this swap but kept the 3.5" bore and used mildly ported P76 heads.  He was disappointed with the result.  I'm quoting "She wouldn't rev...".   Things might be different now....

Greg






left to right: Buick 215, Rover 3.5\\3.9, SB Chevy 327, Buick 3.8 V6 (odd fire), Buick 300, P76, Buick 350(73-80), Buick 340\\350(66-72)

Well, with a 3.85 stroke and 3.5 bore would you expect it to rev?
Just curious, if you were to either powder coat or jet hot coat the 300 block do you think they'd notice it was iron?

Jim

Perhaps I'm too old school ? I think a lightweight sports car should rev. Not having experienced the bliss of Bad Ass Torky Accelleration,(BATA) for short, perhaps I'm too quick to judge. Not knowing any better, It "seems" like having 30-40% more rpms available, might be fun ?  Long Live RPM, roverman.

A bigger bore could fix that.