Datsun Roadster Forum-311s.org

All,

One of my projects this year will be a Rover V-8 in a 311. Has anyone done this, or know of a project that is underway? I need to find a few facts first. Weight difference, size ( width and height mostly). I also need to find a different rear Diff, as the stock diff wasn't designed to hold 250 -300 HP. I've been wanting to find a full floater diff with removable center, I.E. Ford 9 or similar, again weight comparasion. This is starting out as a street machine so I'm not looking a IR diff's ( yet).... So you get the idea. This car will be a street machine, unless SCCA / Vintage finds a class for such a car. I'm planing on a full glass front clip and rear 1/4's as well. Basically a Cobra in different clothes. Many of the MG guys have been doing this, so I figured why not a 311, its built better and has nothing to do with Lucas. Again this is one of many projects, but it will happen and at least get started this year.

JC

Its not the diff that is the issue, its the axels. I have seen a V-8 in a roadster but how is it going to mess with the weight distribution? I think the one that I saw was a ford, it wasn't that well installed. I think getting it to fit under the hood is the issue. If you went with a dry sump, that might help but they tend to be on the tall side. With the MGs, they were actuially raced with a rover v-6 or perhaps a v8. It was a MGC that was most commonly done. There is no replacement for displacement however.

Just my $.02
Will

Will,

The Rover V-8 is all Alum. therefore the weight is very close to the iron four that is coming out. The Ford, Chevy's etc.. are way too heavy and large. The Rover is a compact 8 with a small footprint ( the exact size is what I'm searching for currently) I may need a sump depending on how it sits in the frame. The axle's in the 311's are indeed not up to the task, but side bearings and pinion are not as well. I'm going to persue a light weight locking diff. Which will be easier to find than a LSD for the 311 anyway.
The MG guys ( I used to work for British Leyland ( Jaguar), so what they are doing is very familar to me. They are using the Rover 8 due to it's cubic inch, up to 308 in its last state in a Rover. It started life as a 215 cc for GM back in the early 60's. Anyway, the project is not without road blocks, but they will be worked out in order. Don't get me wrong, I love a highout 4 cylinder, but this project just seemed natural. I have been setting up 427 Cobra's for a vintage race the last 2 years, driving those cars is the something everyone should expirence once in a lifetime.

JC

I started looking into this, let me check my history file. I think the V8 weighs LESS than the 4 cyl.

Found this:
Courtesy of:http://au.geocities.com/p76cortina/P76intoTC.html

I thought this was interesting:

Brief History of the Leyland P76 4.4 V8 and how it relates to the Buick/Rover 215/3.5 V8 and the Buick 300 V8

* Buick 215 sold to Rover in 1963 apparently because of high production costs (lots of blocks thrown away due to poor casting technology/metallurgy of the time).


* Buick 300 replaces Buick 215 in 1964 but has cast iron block and for 1964 only the heads are aluminium and will fit Rover 3.5/Buick 215/P76 4.4 without modification. 1964 Buick 300 heads are considered superior to Buick 215 and early Rover 3.5 heads because of larger exhaust port outlets and ability to easily fit larger valves.


* Buick 300 gets cast iron heads in 1965 which can still be made to fit the Buick 215/Rover 3.5/P76 4.4 - but much more work required. See for example here .


* Leyland Australia P76 gets raised (approx 17mm higher) and stroked Rover 3.5 block+crank with same pistons but longer rods and bigger main bearing shells in 1973 - new capacity is 4.4 litres. Everything from Rover 3.5 except crank and rods can be used on the P76 4.4. P76 4.4 crank can be used on the 3.5 as a stroker crank. See for example here. By comparison, the stroked Rover engines (4.2 and 4.6) kept the same rods, block height and bore as the 3.9 but reduced the piston crown height to accomodate the extra stroke on the crankshaft. The Rover approach is superior because you get the capacity increase without having to change the block height, rod length, inlet manifold width and external dimensions as well as the crankshaft.


* Rover 3.5 gets more webbing and more metal around cylinder liners in 1983 - result is known as the "stiff block".


* Rover 3.5 "stiff block" gets bored out - 3.9 litre, and then stroked - 4.2 litre. These blocks can be retrofitted with stuff from the 3.5 such as the front cover, heads, inlet manifold etc. 4.2 would have different crank and pistons to the 3.9 to provide increase in stroke & capacity.


* More stroking and addition of cross bolts into the main caps results in the 4.6. 4.0 is crossbolted 3.9 - apart from crossbolted main caps new blocks are much the same as the "stiff block" and can still be be retrofitted with old parts from the 3.5/3.9 such as heads, inlet manifold, front cover etc. 4.6 would use different crank and pistons to the 4.0 to provide increase in stroke and capacity.


* Table showing comparisons between engines:

Engine Bore x Stroke Capacity
Buick 215/Rover 3.5 88.9mm x 71mm (3.5" x 2.8") 3528cc
Rover 3.9/Rover Crossbolted 4.0 94mm x 71mm (3.7" x 2.8") 3950cc
Rover 4.2 94mm x 77mm (3.7" x 3.0") 4278cc
Leyland Australia P76 4.4 88.9mm x 88.9mm (3.5" x 3.5") 4416cc
Rover Crossbolted 4.6 94mm x 82mm (3.7" x 3.2") 4554cc

Check out: "Tuning Rover V8 Engines" by David Hardcastle, 1993 (J.H.Haynes and Co. London)

courtesy of: http://au.geocities.com/p76cortina/P76intoTC.html

I'd love to see this swap done. Every time I see an older Range Rover I think about that engine. It's been put in almost every small sports car over the years.

Very strange to see twin SU's on top of a V8 motor. But there are FI models as well.

Let us know if you find any more info!

Leigh Brooks

If you want to short circuit the development process, Craig Halsted has (had?) a Roadster chassis that was already modified to fit a Buick/Rover V8.

On the weight issue, the Buick/Rover should be a little less than the Roadster motor. The Ford small block in stock configuration (iron exhaust, iron intake, iron heads) is about 100lbs more than a U20. With the tube headers, alloy heads and intake, they are about the same, or the scale is tipped to the Ford according to the info that I have seen published.

On the rears, consider a Ford 8 inch. Less parts choices than the 9", but a lot cheaper to run and basically the same design. I think that a Ranger may be a good donor for a rear, but that is either the 7.5" or 8.8" iirc.

There is a junkyard up your way called Perry City Auto, in Trumansburg NY. A friend and I used to buy Jaguar engines and all kinds of "Barn Cars" back in the late 80's from him. (XK 140' and XK 120's for $1000.00 or less) He had huge old chicken coops filled with cars, Super Bees, Superbirds, anything you can imagine. He liked Nash's, there were 72 of them in there last time I went up. The owner was a real character, but he may be worth a try. If he likes you, he'll show you his good stuff. He was old then, so he might not even be around anymore.

I kid you not...My friend did all the business dealings with the guy, It was like I wasn't there. He wouldn't even talk to me until his cat came over and sat in my lap, then all of a sudden I was no longer invisible and he acted like we were old friends. Worth a try, he had lots of cool stuff

All,

Great ideas and information. I will definetly be looking up Perry City, XK120 very nice, but I'm sticking with the 311's...can't afford what it takes for the Jag's. So it sounds like weight is not a problem, now to find a couple of Rover engines and researching 5 speed gearboxes. The Ford motorsports 8.8 diff has had issues as of late, Superformance used them in their 427 Cobras, the track cars are coming apart, very messy, the axles are breaking away from the diff. But the Ford 8" may be a donor, if a good LSD or locker can be had. Thanks all for the input, it would be great to keep this thread going somehow, so we can keep adding information till one gets built. I'm planning on full documentation and photos for this project as it will most likely become a how to.

JC

I thing I did run into 1 thing, the olds and buick heads an blocks don't interchange, one of them, the olds I think, had more head bolts because they were available supercharged, so be careful if you are buying pieces.

Maybe move this to swaps and keep it as an open thread?