Tuned 1098 v's 1275

[zippy500]

which do you think would be better

tuned 1098- lcb manifold/system, hif38 carb, 940 head+rolling road or a standard 1275 engine ( which by the sounds of it are becoming very rare.

Or is there no subsitide for cubic capacity.

just a hypothetical ques.

Cheers

[bmcecosse]

The 1275 is always going to win!! After all - it has the HIF38 and the 940 head - and the Marina ex manifold is not too bad. My own 1098 with all that stuff goes very well - but my 1275 Mini (actually 1340 now) with 286 cam/S head and HIF44 carb produces almost twice as much power. There are 1275 in-line units out there - always some on ebay - unfortunately there seem to be very few in Ecosseland (there is an expensive one now only 10 miles from me - but the missus says NO) - and those which do appear are very highly priced.

[zippy500]

so do you think its worth doing to a 1098.

I reackon it will cost about £300-£400:o (manly because only LCB make a freeflow system about £250(unless anyone knows of a different make to try)) .

[chrisd87]

You could try using the Metro cast-iron exhaust manifold, which Vizard says is basically as good as an LCB. If you can get a seperate one from an MG metro that would save you having to hack the inlet off. You'd need to get an exhaust to fit but you could still save a few bob.

[d_harris]

I'm warming over my 1098 with a hif38 hooked onto a k&n, hopefully a 295 head, and a maniflow exhaust (Manifolds are yet to be decided on - depends what I can lay my hands on)

This is all hopefully going to be done on the cheap, and will act until I can sort out a hot 1275.

The REALLY important thing to think about if you are adding more go is to add more stop! Again, as a temporary measure I'm using 9" Wolsely Drums until I can get hold of some discs

[bigginger]

There are 1275 in-line units out there - always some on ebay

My 3 have cost between £0 and £110. It must depend on your willingness to travel and collect.

[zippy500]

Doesn't the metro manifold shape completely wrong way, like the mini's being
transverse fittment.

[chrisd87]

The exhaust would, but the manifold exits pretty much directly downwards so an exhaust could be fabricated to suit an in-line engine. Remember that the mini used the same inlet/exhaust manifold as the Minor for a long time.

[Kevin]

like the mini's being

But the Mini thousand fits fine and enables to to fit an 1 1/2" carb and retain the standard exhaust if you wish.
I have a 1275cc Midget engine that needs a bit of work going spare if you are interested.

[bmcecosse]

Dan - Once you fit the big drum brakes you will realise how good they are and you'll not worry about discs any more!

[paulhumphries]

My 1956 Austin A35 (948cc) kept blowing exhaust to manifold joint.
In the end I fitted a 1098cc SU carb & manifold off a spare A40 together with a cast iron (instead of pressed steel) clamp.
The car would tick over but not rev.
In the end it blew the joint again and then reved !
This made me realise how much back pressure in the exhaust can affect running.
Turned out there was a faulty batch of silencers used in making some systems for the A35 that had too small perferations inside.
I opened the silencer up, knocked out one baffle and drilled larger holes in the other before welding back together and refitting.
The diffference in performance was amazing yet noise level only increased at high revs and then almost a Mini type "rasp".
What I'm trying to say is, from my experience is, that a free flow exhaust CAN make quite an improvement without other tuning.

BTW I haven't done it yet but have found a manufacturer of stainless exhaust near me that will fabricate out of slightly larger bore pipe (say 1.25" instead of 1") with bigger silencer. Guess, when current mild steel come to be replaced, what I'll be fitting

Paul Humphries.

[d_harris]

I'm thinking more of the insurance.........

[aupickup]

1275 and discs makes no difference from a 1098 on my insurance

[bigginger]

Same for me. I guess it may be an age thing though.

[bmcecosse]

Yes - exhaust does matter. the Mini lads fit a 'stage 1 kit' which is essentially just a free flowing exhaust and a non-exhaust heated inlet manifold - and get substantial improvements. Exhaust is next on my list of things to do on my Minor - but so little time, and so many other things to do!

[zippy500]

yes.. but Mini owners are spoilt for choice with exhausts and tuning kits. The only exhausts make for moggys is maniflow( havnet come across any other make)..which does seem a bit expensive.

[bmcecosse]

Indeed -my plan is to modify a Mini lcb (got two spare) - and then make up a pipe and silencer after that. Winter project!!

[chrisd87]

I assume that despite the small pipe size the main restriction of the Minor exhaust is the silencer, so surely it would be possible to make a high-flow exhaust 'on the cheap' by chopping out the silencer and welding in a better flowing item?

This could have beneficial effects for otherwise standard Minors because Vizard seems to think that a less restrictive exhaust helps economy quite substantially. Would probably spoil the trademark moggy fart though

[salty_monk]

You could just chop it out altogether & put an extra bit of pipe in there....

Or you could open it up take out some of the baffles & patch it by welding or even a plate put on with high temp silicon & rivets (that's a kit car trick...)

If you can get more air flow out the exhaust you probably need to find a way to get more air into the engine to make a huge difference & more air in means more petrol so bigger carb & better head.

Dan

[bmcecosse]

The 'standard' mod was to remove the silencer and fit a Sprite MkI straight through silencer. This could either be fitted up front - or at the back - although not much room at the back.