Thread: P76 crank and a 3.5 Stiff Block?

Heard of all sorts of cranks going into blocks that you'd wonder how they fit or with so much throw how the pistons stay in the bores.

Usually happens though from a bit of mucking around like custom oil sump and machining out clearance in the bottoms of the bores to allow the conrods and counterweights to not hit when they rotate. Sometimes they convert from two bolt mains to four or six depending just to hold the crank in there. Depends on what potential they aspire the engine to have though this doesn't come cheap.

If you to alot of research and measuring beforehand you might be able to fit into that 3.5 block. Then again why not get a block with the crank you want already in it and redrill to whatever transmission bolt pattern you need ?

There is a guy in NZ who has one I've seen it on a web site somewhere.

If it will fit, you'll need shorter conrods.

Ron

Not neccesarily, changing the the gudgen height in the piston has the same effect, ie find pistons the same size with the pin in a differnt spot and machine the crowns to suit if need be. This is how lotts of strokers are done. Holden used this trick to make 202 and 173 engines a 202 is a stroked 186 and 173 is stroked 161 but all holden reds have the same lenght con rod it's just the crank and pistons that are different. You can also make a 235 cui red motor by machining a 170 pursuit Falcon crank and pistons to slot in a 186 block these also use holden rods. You cut the ends off the Falcon crank and drill the ends, you then machine the ends of a holden crank and make them an interferance fit in the Falcon then weld them in, grind the main and big ends to holden bearings and your away. This make a really tough red motor with heaps of torque. Super quick in and LJ Torana takes a good 350 in HQ to catch one.

Hey Shaun,

Any info on what to use stroke a Rover V8 3.5? - what pistons / crank to use etc? as most parts of a stroker kit would come from a production which of some sorts?

I was also told:

<div class='quotetop'>QUOTE</div><div class='quotemain'>details for the 5.2 -
they use 3.9 block, 4.4 leyland crank either ford302w or chev307pistonswith
the right deck height , 3.9 conrods are used, ive even seen jaguar
pistons used also .

mine is a 3.5 stiff block from 84>RRand as i said
it has 4.4 leyland crank, 3.5 rods ,and pistons that had the right deck
height, the maching I had done at a place in ferntree gully[vic] called
prostroke engineering unfortunately no longer in business.

and a mate
of mine who is a fitter by trade assembled it up for me all up costs
was around $4800-$5000 installed its not any thirstier than 3.5. 4.5
kilometers per litre on gas, ie I get 450 kfrom 98 litres of gas ,
petrol 260klms from 45 litres and i run .996:1 transfercase gears in
lt95 gbox and bfg32x11.5x15tyresi used a wade 259a cam it has good lift
and duration and power from idle to 4500rpm it produces about 225hp
approx [/b][/quote]

This gives a healthy 4.5 litres!!!

Originally posted by shaunp
Not neccesarily, changing the the gudgen height in the piston has the same effect, ie find pistons the same size with the pin in a differnt spot and machine the crowns to suit if need be.

True. I was thinking of using Rover conrods.

I just happen to have the old 4.6 (pulled out of my P38A) which I may be selling shortly.....

Ron

See heres the problem.
I have put a new 3.9 into my 86RR.
I have the old 3.5stiff block sitting in my garage and the versitility of the rover engine has me confused what to do with it, I have bought an engine stand and it is going to be my new pet project but what do I do rebuild it standard but hotter, make it into a 3.9, stroke it...so much you can do has me confused...
So I welcome any..polite suggestions from this esteemed and knowledgble community..

DD

See if your local library has "Tuning Rover V8 Engines" by David Hardcastle.

Ron