paul_mcq
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| posted on 14/2/05 at 02:52 PM |
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head choice??????????
well lads hows it going, i'm tuning my a series up and need to now if there is much difference between a stage 3 and a 4. theres bout £100
difference is there any performance change?
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stevebubs
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| posted on 14/2/05 at 03:18 PM |
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To be honest, it depends on who is doing the tuning.
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Marcus
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| posted on 14/2/05 at 08:21 PM |
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I agree with Steve, one man's stage 3 is another man's 4!
I was once offered a stage 3 crossflow with STANDARD sized valves.
You're probably not going to get the benefit from stage 4 (also known as full race) on the road. If it's going to be a track car it may be
worth it, depends on the spec of the rest of the engine.
Marcus
Marcus
Because kits are for girls!!
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Jon Ison
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| posted on 14/2/05 at 09:14 PM |
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if they a proffesional heads ask how much they flow......if they dont know they aint been developed properly.
compare the flow rates, not as stated above "stage 3" "stage 4" that could meen anything.
allso beware polished ports....
[Edited on 14/2/05 by Jon Ison]
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paul_mcq
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| posted on 18/2/05 at 01:32 PM |
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cheers lads. i'm looking to change the pistons in the engine which i need bit of adive which ones to go for. i'm putting bigger ratio
rocker arms in and a race cam. keeping the 1.5 in su carb. is there anything else i can do to inhance the engine?
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britishtrident
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| posted on 18/2/05 at 01:45 PM |
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Put a 998 Imp engine in :-) been done a couple of times using the Mini gearbox and lots of alloy welding but the results are IMPressive.
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Stu16v
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| posted on 18/2/05 at 05:42 PM |
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quote:
Originally posted by paul_mcq
cheers lads. i'm looking to change the pistons in the engine which i need bit of adive which ones to go for. i'm putting bigger ratio
rocker arms in and a race cam. keeping the 1.5 in su carb. is there anything else i can do to inhance the engine?
With an A series engine, the only thing that restricts engine tuning is the amount of money you want to spend.
I have played with quite a few A series motors over the years. The head is a good place to start, and the biggest restriction in getting power out of
the motor. I wouldnt advise fitting a race cam, especially if you intend to run a single carb. All it does is push the usable power right up the rev
range - to the point where you need better/bigger carbuation, so you end up with an engine that is a pig to drive, and restricted power at the top.
Net result, a worse engine than before! The high ratio rockers will accentuate this. Instead, go for a fast road/rally cam (with your rockers...), a
lot better suited IMHO.
If you can find one, fit a carb and manifold off an MG Metro. Not the ideal solution, but far better than an 1 1/2 SU. A nice LCB exhaust manifold and
a decent exhaust, to finish off, and you will have a lovely little engine.
A word of warning, make sure that the valve springs are capable of coping with the extra lift of your chosen cam, with high lift rockers. Quite a few
standard ones wont...
Finally, they are quite expensive, but IMO make *such* a difference to the sound/smooth running of the engine - a cam belt conversion kit. Quite
simply the best thing I did with my Mini...
HTH Stu.
Dont just build it.....make it!
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NS Dev
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| posted on 18/2/05 at 05:45 PM |
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Just to back up Stu's point, bin the 1.5" su and fit 1 3/4" su and water heated manifold from an MG metro, definitely the simplest
and most effective mini trick in the book!
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Peteff
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| posted on 18/2/05 at 08:09 PM |
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A good exhaust, something like the Maniflow system with a Cooper 3 branch or LCB really makes a difference to a standard engine. My old one pulled
like a train with just a head clean and skim, exhaust and carb/manifold sortout. It was only a 998cc but it used to go well.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Marcus
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| posted on 19/2/05 at 10:25 AM |
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My mate just had his 1275 Midget on the rollers, was expecting 50 - 60 at the wheels, has 45 weber, oselli head, 285(ish)cam and an LCB manifold. Was
gobsmacked when readings came back at 85 bhp at wheels!! That's a serious A series. (tested at John Noble in Chesterfield so I believe it)
Marcus
Marcus
Because kits are for girls!!
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