V8 Just out of curiosity??

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V8 Just out of curiosity??

Postby cooperman » Tue May 07, 2019 11:15 am

I know people have fitted a Rover V8 into an OHC using front crossmember but is there any reason why you can't fit a V8 onto an OHV crossmember? The engine mounts will need modifying anyway, is it OHC brakes will cope (as long as you're not racing it) and the OHV will need brakes and stub axles beefing up, or is there something more involved? Springs won't fit, arms not strong enough etc? Just spitballin' but interested in any knowledge.
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Re: V8 Just out of curiosity??

Postby 1972nail » Tue May 07, 2019 5:32 pm

You need OHC springs, brakes and stub axles at least, the Rover V8 is and alloy lump which is about the same weight as a slant 4. The simplest brake upgrade for OHC stub axles is to fit M16 calipers. A vast improvement over the P14 standard OHC calipers. Bigger pistons and the larger pad area certainly add a lot to the braking power.

Strictly speaking you need special bolts to fit the metric caliper onto the imperial threaded stub axle but I've done it (and many other owners who use their cars for competition) using the existing bolts without problems.

The P16 caliper is the imperial equivalent of the M16 but they are now difficult and expensive to find. Also the P16 has 15% less pad area than the M16.

A rear axle upgrade should be a priority as well, probably OHC is the easiest option here but a modified Salisbury 4HA is the ultimate but a Salsbury 6HA from an MGB or a 7HA from a Morgan could be cheaper alternatives but with fewer ratio and LSD options. They are weaker than the supposed 4-500 BHP rating of the 4HA but they are still a lot stronger than the OHC axle.
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Re: V8 Just out of curiosity??

Postby cooperman » Tue May 07, 2019 9:27 pm

Thank you David
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Re: V8 Just out of curiosity??

Postby pbottomley » Tue May 07, 2019 9:59 pm

OHC subframes are also a little stronger, but its no issue to weld on bits and bobs to strengthen a subframe to the right standard.

OHV one suffer stress fractures where steering rack bolts on due to extra weight of OHC, to these have a thicker grade steel in this part of the subframe
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Re: V8 Just out of curiosity??

Postby cooperman » Tue May 07, 2019 10:02 pm

Interesting... thanks Paul
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Re: V8 Just out of curiosity??

Postby 1972nail » Tue May 07, 2019 10:50 pm

pbottomley wrote:OHC subframes are also a little stronger, but its no issue to weld on bits and bobs to strengthen a subframe to the right standard.

OHV one suffer stress fractures where steering rack bolts on due to extra weight of OHC, to these have a thicker grade steel in this part of the subframe


I thought that was just HB and very early HC subframes. From late '71 on all HC subframes were the same except for the engine mounts and the fixings for the ARB on the rear outriggers, or am I mistaken. Mind you, I have seen a later HC OHC one crack there when used in competition, so worth checking anyway.

Worth doing in any case would be to reinforce the holes for the bottom wishbone bolts by welding on large washers. This does wear and elongate on OHC cars more often than OHV cars, especially if you fit wider wheels.
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Re: V8 Just out of curiosity??

Postby BobbyMel » Wed May 08, 2019 7:26 am

Sounds like you've got an interesting project lined up Marcus...
HB 368

1970 - Vauxhall HB Viva Estate....114 BOB
2015 - Vauxhall Astra 1.4 Excite...NL65 MDO
1987 - Austin Montego 1.6L....E375 JRV
1995 - Rover 216 Coupe....N622 VOA
1968 - Vauxhall HB Viva Estate....TMH 833F
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Re: V8 Just out of curiosity??

Postby cooperman » Wed May 08, 2019 7:14 pm

No no Bob, it's a HC shell that I've bought from Fred and it's an 1159 on the log book. Because it is a shell I immediately thought V8, not for speed but for sound! Then it looks like the bulkhead needs cutting plus running gear and then it's IVA time which is a headache I don't want. So I picked up an SL90 1159 engine and box which drops straight in... then when at Donington with Fred at the weekend I heard the Baron and I started thinking again if you could drop the V8 onto the existing crossmember but as far forward as possible without cutting the bulkhead, therefore no IVA. I think it's going to be the 1159 but that V* sounds so good!
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Re: V8 Just out of curiosity??

Postby 1972nail » Wed May 08, 2019 8:18 pm

I'm planning on introducing the idea of a modern transplant in the next club magazine...... No IVA involved and the potential of lots of go. Might be right up your street Marcus.
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Re: V8 Just out of curiosity??

Postby cooperman » Wed May 08, 2019 9:48 pm

Interesting David, I'll look forward to reading that
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