The V8 Owners Forum -

Hi there guys, once again find myself thinking up ideas for my next rebuild even though ive just finished my current (landy 5.0) - was wondering if anybody had any experience with the rover V8 5.5 litre stroker kit? Cost? and is it worth it? What pistons and rods? Any block mods? Is it better just to optimise your 5 litre?? Any power figures?? Why arent they more popular??

The Rover heads struggle to feed 5 litres, for 5.5 litres I think they would struggle to get past 5,000 rpm. I suspect that is the main reason, although I would expect that big an engine to be quite fragile as well.

Alan

Well maybe, but in combination with stage 4 or Merlin/Wildcat heads couldnt it work - there are 5.5s about - boost apparently sell them and V8 Dev - would be great for low down grunt

You need to speak with Rob Robertson. He is member of the forum (v8rob).

Hi
If you can afford wildcat heads I would not wast money going for 5.5 litres. Build a bullet proof bottom end around an engine with a displacment about 4.8 litres, big bore as you can go with short stroke 2" big ends. If you stick the wildcat heads on a 5.5litre bottom end it will shake itself to bits before it makes peak power.
With a 2" big end you have a good choice of chevy rods, you can bore it for chevy 305 pistons and add a bottom end brace and it should make an engine with a good spread of power on a sensible budget. you may even be able to find a set of used NASCAR rods in the right big end size at a good price which would be plenty strong enough!
Best regards
Mike

If engine will shake, it need rebalancing.
V8 developments 5.5race engine will rev +7000rpm without issues say Rob..
4.8L bottom end is quite small for wild cats if engine is road use.

5.0 WILD CAT ENGINE 398 BHP @ 5950 RPM, 340FTLB @ 5600 RPM
http://www.automotivecomp.com/v8engines.htm

In my mind i don´t see any sense for those heads before someone give me +420hp dyno results..
You can get same and better results for 5.5litre bottom end and stage 4/5 heads for V8 developments or J.Eales..
And lot of more low rpm grunt witch is very important..

You may even get better performance ported rover heads, because you have got more torque to use hole rpm range..

Buzz up 7000RPM is not really the problem but how long can you stay in this RPM ?

5.5 has a rod/stroke ratio of 1.54. A guy on PH has one of this 5.5 engine and it uses chevy 5.7" rods.

Where is daxtojeiro?

He has got V8Developments 5.4/5.5litre bottom end, not sure witch heads?
I think he can tell more of this bottom end..

I was thinking is there any reason to go over 5.3litre. 5.4/5.5 is only 100-200cc bigger.. Of course it is ultimate engine, but..........

If the 5.5 is a new casting and well balanced and not just a ground out 5.0 litre then Shirley it will be strong enough for mid range grunt. But wandered about cost, block mods and dunk results, Chevy 5.7 has signIficantly bigger valves then wildcat stage 1 heads, and ford 5.0 also does It not, but
Nobody says they are to race orientated???

Add the cost of 5,5 litre bottom head and matching heads and you wil have figures that don´t make sense compared to e.g Chevy LS series engine. IIRC weakest variant is easily 300 hp and the practical limit for a street engine is somewhere around 600 hp mark. If you tolerate lumpier idle the limit is way beyond that.

If youor car and wallet can justify Chevy LS that is the way to go. Ford Modular and Chrysler Hemi are currently well supported in US aftermarket business but tend to cost more than Chevy.

£4250.00 for 5.5 short block : http://www.v8developments.co.uk/prod_eng.html

I was wondering how long it would take for somebody to mention a chevy LS block;-) But think of all the fabrication and fitting to the transmission, engine mounts etc, would not just drop into my defender, by the time i spend money and time sorting all that out, I could just purchase a 5.5 rotating assembly (about 2 and a half grand) and 1800 for wildcats, 1300 for merlins or 600 to put bigger valve seats and Tuscan valves into my stage 3 heads and im at the power level of a mid range LS, without any fabrication or faf. would be at least 4-5 grand for just the LS engine and then i would have to fit it. The point is with a RV8 i that I am already half way there. If I had no engine and a blank canvas I may agree with you.. But then again I love the rover, if we abandon it we may aswell abandon all tuning and development of any older engines, isnt that what this forum is all about??

I'm running a 5.7 twin turbo in a Dakar (RR classic) and there's a defender running a 7.6L Big block:
http://mez.co.uk/forum/viewtopic.php?t=793

Discussing this topic today over my mates crank grinder - how would one piece together this 5.5 kit - is it a 95mm stroke and 96mm bore?? Can you use off the shelf rods and pistons from Chevy?? Thinking of what my 300 heads will eventually feed...

Hi
If you are prepared to go wet liner then you can go up to a 3.875" or even 4" bore and use 1.8" big end chevy rods and you can probably get close to a 3.75" stroke. . .but why waste the money? it will be delicate, you will still have problems with the cam selection and the lobes being too close to the crank, basically you have to fill the rover with chevy small block bits until there is no rover engine left, just buy the chevy in the first place! Or You could buy an LS engine and make some decent power reliably. . . If you have buick 300 heads then just buy the rest of the buick 300 or even a 340, that is a better place to start as it has close to large capacity already.
Best regards
Mike