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PostPosted: Wed May 20, 2015 11:25 am 
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Looking for the opinion of someone with roller tips fitted.

On the engine I have the head is being de coked and the valves re laped in and a small bit of cleaning and porting this is being done by Chris in WMR, I was tempted to send the head to a machine shop for a full on porting and polishing and slight skim and pressure test.

I have a hif44 with a yellow needle and K&N I will be getting an LCB and Rc40 as well, the engine will be getting some light maintenance new oil pump, water pump, thermostat and copper head gasket set, lightweight flywheel and new AP clutch

I didn't want to split the engine from the box to fit a cam at this point but I am wondering will 1.5 roller rockers make much of an appreciable difference I understand the theory and the altered lift in the same duration but is it worth it for real world results? In time I might uprate the cam and it may be worth working the head a little more at this stage?


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PostPosted: Wed May 20, 2015 12:07 pm 
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Whats your location?: Longford
Region: Eastern
What Minis have you?: 1971 Mini Marcos.
1984 Mini Sprite
PROJECT X
Modifications: 1380cc
Weber45
S/C CR gearbox and drop gears
Location: Longford
Probably a waste of time fitting 1.5 rockers on an old worn cam to be honest. You'd be better served by fitting a new cam while the head is away getting the work done, fit an adjustable timing chain and new cam followers while you are at it .

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PostPosted: Wed May 20, 2015 12:18 pm 
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Bit of a minefield when it comes to what to do with head work and cams. I am new to mini engines, I thought it would be fast road rally etc but minispares alone have so many options.

The original engine is actually only on 40k so the existing cam is probably fine in terms of wear. The adjustable timing chain is this just a varient of the duplex kit?


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PostPosted: Wed May 20, 2015 12:35 pm 
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Whats your location?: Longford
Region: Eastern
What Minis have you?: 1971 Mini Marcos.
1984 Mini Sprite
PROJECT X
Modifications: 1380cc
Weber45
S/C CR gearbox and drop gears
Location: Longford
If you are looking for power then you need to be able to time the cam correctly, every little bit of hp helps.
Standard cams are little more than pips on a gerkin, and never going to produce anything in the way of power, the MG Metro cam is probably the best standard cam.
I'm a bit old school so would suggest a 276 cam or if you are doing more town/city driving then a 266.
The current version of the SW5 isn't bad either.

The roller rockers can always be added at a later date.

Woody is off line at the IMM in Lithuania at the mo, but I know that at this stage he would be screaming about getting a dizzy with an advance curve to suit the cam at this point, so that's something else you will have to consider.

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PostPosted: Fri May 22, 2015 11:25 pm 
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I was reading up on David Vissage and tuning the A series engine. You have me thinking as well now about uprating the cam and skipping the roller rockers for now as its not a head off job to re fit.

In terms of distributors is lumenition and Aldon relatively equal or which would you reccomend. I hadnt intended on looking for power at all as the car is for my wife to be, but it makes sense or so i tell myself, to not only freshen up the engine but tune it a little at the same time.

Saorla's daily is a 1.2 fiat 500 so the mini will be more than quick enough for her with a lightened flywheel, stage 1 and a fast road cam


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PostPosted: Sat May 30, 2015 12:18 pm 
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Whats your location?: Drogheda
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Leave the dizzy as is (if its the one that came with the engine) and fit the high lift rocker for an instant power increase on any engine. Parts like rockers, manifolds and carbs are sound investments as you can carry them to the next phase of development. What engine is in the car?

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PostPosted: Mon Jun 01, 2015 3:01 pm 
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I was talking to Chris in Waterford Mini Resto's, he is doing the work on the car. He reckoned for now to leave well enough alone, that it will have enough poke for her and given that the list of parts I was buying was growing every day maybe it's no harm for a while to leave off it's not a blank cheque car I have been saving my arse off for it.

I have a pretty new HIF44 bought with a water cooled manifold and a K&N pancake filter, a stage one needle and a maniflow LCB and downpipe and rc40 sidestyle back box. I also picked up a light weight flywheel a while ago, so am adding an AP clutch in as well

I am still tempted to go further though. It's a 1275 sprite engine on 46,000 miles, Chris is taking the head off the de coke and clean it up a bit, I ordered up a new gasket set, oil pump, water pump, thermostat, new radiator and hoses, new plugs, leads, and I wasn't sure about the distributor and condensor etc. I also ordered a new loom as the original was spliced and tatty looking, so the engine bay should look nice and fresh

I was just really tempted by the minisport camshaft when I saw how cheap it was, and it's a more involved job than roller rockers so I thought it might make more sense to do now, when the engine is off the subframe and the shell is away for paint.


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PostPosted: Mon Jun 01, 2015 3:09 pm 
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Whats your location?: Longford
Region: Eastern
What Minis have you?: 1971 Mini Marcos.
1984 Mini Sprite
PROJECT X
Modifications: 1380cc
Weber45
S/C CR gearbox and drop gears
Location: Longford
Making the whole head breath a bit more will give the biggest gains.

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PostPosted: Mon Jun 01, 2015 5:53 pm 
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I have a track car that I had the head polished on and a 4 branch and the difference was huge so I would be really tempted to get the head flowed and ported a little.

I have been used to modern jap stuff for a while where power gains are cheap to start then gains have massively exponential increases in price and results.

It's nice to see that with an A series it looks like a few hundred quid can totally change the character of the engine.

Are the minisport and minispares heads a special casting or just a standard head flowed and worked to the specifications they have developed?

If a standard head could be worked likw a stage 2 or stage 3 for a reasonable out lay i would just do it now


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PostPosted: Mon Jun 01, 2015 6:02 pm 
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Joined: Fri Feb 04, 2005 10:05 am
Posts: 4657
Whats your location?: Longford
Region: Eastern
What Minis have you?: 1971 Mini Marcos.
1984 Mini Sprite
PROJECT X
Modifications: 1380cc
Weber45
S/C CR gearbox and drop gears
Location: Longford
They are all just standard castings.

You can get alloy versions though in 5, 7 and 8 port configuration. Then you are on to twin cam heads.

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PostPosted: Mon Jun 01, 2015 6:26 pm 
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Any idea what cost is involved in going to stage 2 or 3, as in do you have to go with uprated or larger valves and do the tappets and springs etc also get changed.

I'm based in Wexford but I have heard of a rally man around Gorey that's meant to be very talented with head work.


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PostPosted: Mon Jun 01, 2015 7:17 pm 
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Joined: Fri Feb 04, 2005 10:05 am
Posts: 4657
Whats your location?: Longford
Region: Eastern
What Minis have you?: 1971 Mini Marcos.
1984 Mini Sprite
PROJECT X
Modifications: 1380cc
Weber45
S/C CR gearbox and drop gears
Location: Longford
It's 22 years since I got any engine work done so can't help you with current prices.

I went down the route of getting a 1380 engine from MED in the UK, it's still going grand when it gets out.

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PostPosted: Mon Jun 01, 2015 8:44 pm 
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I might look up the guy that did the head in my saxo vts track car and see what he would charge.

At some point in time I would like to build a mini for myself but I might not go A series so it would be nice to have one for the other half with a more faithful to the originals tuning set up


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PostPosted: Wed Apr 05, 2017 10:43 pm 
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Whats your location?: Dún Laoghaire, Dublin
Region: Eastern
What Minis have you?: '93 SPi cooper
Location: Dún Laoghaire, Dublin
Sooooo.... how did this work out?

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PostPosted: Sat Jun 03, 2017 4:50 pm 
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Whats your location?: Dún Laoghaire, Dublin
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What Minis have you?: '93 SPi cooper
Location: Dún Laoghaire, Dublin
?

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