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Engine Ideas - Advice
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Author:  Albino_Hedgehog [ Tue Jun 14, 2016 8:30 pm ]
Post subject:  Engine Ideas - Advice
Introduction

Hello,

I am Matt, I am from the UK, in fact I lived just a 5 minute walk from the former Mini birthplace the Longbridge factory.

I drive a 1990 Mini City E, I have been on the road for around 18 months, and have loved every minute of it!
So far I have done nearly 20,000 miles in my little car, and have no intentions of stopping anytime soon!

My Ideas

I am looking into ways of improving my standard 998 in terms of daily driving.

Now I know over there in Australia, you are quite familiar with the 1098cc engine, so I believe you guys may be best qualified to give me advice...

I have the opportunity to purchase an 1100 engine quite cheaply, but they seem to have a bad reputation over here, and are often passed over in favour of the 998, or the 1275!

I also have recently been given a few other items that I feel would make a difference, including a 12g940 Metro Monaco head.

The proposed setup of my car would be the following:

1098cc Engine
Reece Fish Carburettor
Maniflow alloy Inlet manifold
12g940 Metro Monaco cyl head
Cooper freeflow exhaust manifold
RC40 exhaust


What are your opinions on this?
Author:  slide [ Wed Jun 15, 2016 12:52 pm ]
Post subject:  Re: Engine Ideas - Advice
Which cam are you thinking of using? This engine was installed in the Min K here. There even used to be a race series for them back around 1970. They're long stroke, which is good for making torque, but can be harsher than a 998 and more prone to crank breakages if revved too high for too long. But for a road car they can be made to go well. Not so sure about the Reece Fish; weren't these fitted mainly to the smaller bore engines?
Author:  timmy201 [ Wed Jun 15, 2016 1:47 pm ]
Post subject:  Re: Engine Ideas - Advice
What type of engine are you looking to build? Stock, a fun road engine or a full on powerhouse? Do you have a target hp figure in mind?

The Reece Fish has a different stud mounting pattern to SU carbs, so you'd have to get a special manifold, or redrill the minispares one. You might be better off with an HS4 for a mild engine, or an HS6 or HIF44 for a worked one.

The 12G940 has much smaller combustion chambers than a 12G202 or 12G295 head, so you'd need to make sure your compression ratio is correct and suits the cam etc.

If I was in the UK I'd be building a 1275 engine. They are much cheaper and easier to find over there (one of the reasons we use 1100 engines) and they have a lot more potential for power..
Author:  1018cc [ Wed Jun 15, 2016 3:43 pm ]
Post subject:  Re: Engine Ideas - Advice
timmy201 wrote:
If I was in the UK I'd be building a 1275 engine. They are much cheaper and easier to find over there (one of the reasons we use 1100 engines) and they have a lot more potential for power..


If Matt is quite young he may run into insurance $$$ problems for a 1275 in the UK.

I'd personally go for a 1275 if I could find one cheap enough but then again, once you are over that 'magic' age of 25, insurance deem you instantly responsible to own whatever you want :-P

I have heard of people running Reece fish carbs but having never played with one I'd probably just go an SU because I know how they work and I have a wideband in a box for tuning the needle.

People like GR (on this forum) can get big numbers out of his small bores so if I were you, read up on the "project smallbore" and "project 68mm" articles from here for ideas: http://russellengineering.com.au/articles/
Author:  Lillee [ Wed Jun 15, 2016 4:33 pm ]
Post subject:  Re: Engine Ideas - Advice
Hey Matt!

All the advice given here so far is good. Having done this exact thing in the past here are my tid bits:

1) One thing that may influence your decision of 998/1098 vs 1275 is brakes. I could not find what type of brakes Mini City E's come with up front. If it's drums then going 1275 may be an issue for you to get MOT or whatever. If you are running discs then no worries.

2) Here changing engines requires inspection and certified clearances to change your engine number from what it is now to something different. The law here is that you have to have a receipt for the engine block you have purchased in order to transfer it. Laws may vary over there so better to research this ahead of time as it is all extra costs basically.

3) If you are going to build an engine from scratch on a bench before lowering it into the car then yeah as others have said, the amount of money you need to spend to rebuild an engine you may as well invest this into a 1275 as the costs for rebuild will be about the same more or less. You just get more bang for buck on 1275's

4) I'd stick with SU's and a good intake manifold and exhaust manifold to suit. You'll get plenty of hp out of a single HIF44 and they are cheap to find, rebuild and fix.

5) From memory throwing a 12G940 head onto a small bore block isn't exactly straight forward. The amount of money and effort required to do this may be better spent on porting and installing bigger valves on a small bore head, which you can still get plenty of power from if you find someone who knows what they are doing.

6) Cam is a very important consideration for making power

Read this (3 parts) and absorb as much info as you can! http://russellengineering.com.au/projec ... gine-pt-1/

Good luck!
Author:  Albino_Hedgehog [ Wed Jun 15, 2016 6:20 pm ]
Post subject:  Re: Engine Ideas - Advice
Thanks all very much for your comments!



I know the Reece Fish carb is good enough for the engine I am planning, they were used on 1200 Beetle racing so will be good for a fun road Mini!


As you say over here the 1275 is the more favourable engine, because of this reason makes me want to build a small bore, that can also surprise people!

I don't have a hp figure in mind, so would know what to expect from an 1100 in all honesty!

As for the head I am aware that the block will require machining and have taken costs into account!

Thanks
Author:  timmy201 [ Wed Jun 15, 2016 6:59 pm ]
Post subject:  Re: Engine Ideas - Advice
Stock = 50hp
68mm bore GR engine = 120hp
http://russellengineering.com.au/project-68mm-pt4/

Somewhere in the middle would make a great engine for the road...
Author:  simon k [ Wed Jun 15, 2016 9:47 pm ]
Post subject:  Re: Engine Ideas - Advice
leave the 12G940 head - it's a big bore (1275) head, it can be used on a small bore, but if you use anything other than a standard cam you need to grind pockets in the top of the block and other messing around, not worth it
Author:  Albino_Hedgehog [ Wed Jun 15, 2016 10:36 pm ]
Post subject:  Re: Engine Ideas - Advice
Right then,

Assuming I leave the 940 head

Keeping the standard 1100 engine and head combination what would you recommend?
Author:  Lillee [ Thu Jun 16, 2016 8:11 am ]
Post subject:  Re: Engine Ideas - Advice
Albino_Hedgehog wrote:
Right then,

Assuming I leave the 940 head

Keeping the standard 1100 engine and head combination what would you recommend?


Did you read the above article? Do all of those things in that article and the 68mm project and possibly get 120bhp! :D

http://russellengineering.com.au/projec ... gine-pt-1/

http://russellengineering.com.au/project-68mm-part-1/

If I have learnt anything about building engines for power, I've learnt that it's not one single thing that makes power (other than head work and cam), it's many little things, trial and error, experimentation on the dyno, that gives a desired result.

Try this cam, that manifold, this exhaust manifold, smaller chokes, bigger chokes, jets, giver her a few more degrees advance, fiddle with this, optomise that and eventually you get what you want with certain combinations.

You can't expect to assemble and machine components separately and throw it all together hoping for it to all magically gel.
Author:  Albino_Hedgehog [ Sat Jun 18, 2016 6:43 am ]
Post subject:  Re: Engine Ideas - Advice
I have been told to use a sw5 cam or a ACDoDD RT-Cam
Author:  mattsmadmini [ Sat Jun 18, 2016 9:17 am ]
Post subject:  Re: Engine Ideas - Advice
Dude. Read the article provided first.
Author:  Albino_Hedgehog [ Sat Jun 18, 2016 6:45 pm ]
Post subject:  Re: Engine Ideas - Advice
Sorry I was jumping ahead!

Will read those first!
Author:  Ian_B [ Mon Jun 20, 2016 9:12 pm ]
Post subject:  Re: Engine Ideas - Advice
If Graham builds the whole motor on his own dyno and all I believe you will get results.
Do it yourself you will get something good but not optimum.
Author:  Cheeser [ Sat Jun 25, 2016 11:56 pm ]
Post subject:  Re: Engine Ideas - Advice
Hi Matt,
I played with a 1098 motor in the 1970s and used a 11/4" Reece fish carb. The studs are vertical and it will fit on a manifold previously used for an HS2 or H4 carb and some after market manifolds that cater for vertical and diagonal pitch studs. i found the Reece fish was easy to adjust using a vacuum gauge ( not needing different needles or jets like other carbs, but I reverted to an HS4 which I found much less harsh and more economical. The motor was +60 and used a 12g295 head together with 997 cooper cam and was used in a Morris Minor 1000 and a Series 2 Lotus Seven, it went very well and could pull 7k in the Lotus which is light weight and very low geared. The main problem was that I used split skirt pistons and I would find bits of the skirt in the sump. If you put a 1098 together carefully it will rev and not be a problem(I also used a Lightened flywheel and toughened crank together with a damper pully). I would suggest that you probably don't need to rev it beyond 6k to get your car to go very well using a cam similar to the 997 cooper cam. Both the SW5 and ACD RS cams would appear to be modern takes on a 997 cooper cam and will give good street performance with a very good spread of torque. Don't concern yourself about all the claimed bhp figures, just put the motor together carefully taking your time and then get it set up properly on a rolling road with an operator who knows about A Series and SU carbs. Good luck with your build and have fun.
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