1275 tuning - Questions about Vizard and a few more

[GeorgeHurst]

Thanks Roy, your reply suggests I could fit either or. Is there a difference between the two on a durability/quality/performance front or is it just a case of different fittings?

[bmcecosse]

Yes - you can fit either - obviously the 45 D is a later version and should have various 'improvements' built in! So yes - given a choice - go for the 45D.

[GeorgeHurst]

Great, thanks. SimonBBC do a 45D electronic 'sports' dizzy and coil for 68.99 so I think I'll go for that.
Amazingly good value if you think a new coil and vacuum unit is £40

[bmcecosse]

Well - wouldn't be my priority! But if you have the cash burning a hole in your pocket..............

[GeorgeHurst]

No cash burning a hole unfortunately, but I'm hoping the sale of various parts that i am upgrading/replacing will give me a bit of cash to spend on some other bits

[Alec]

Hello BMCE,

does the 45D unit have vernier adjustment?, if not I would prefer to use a 25. More recent doesn't necessarily mean better, as often the reason is to make it for less money and therefore tends to be inferior.

George, what on earth is a 'sports' distributor? The important thing is to get a distributor which has the correct specification for your engine. As it is non standard you will need to do some research with people who have successfully carried out the same modifications as you intend to do. A properly overhauled and set up distributor will cost far more than the price you mention but will give maximum value for money.Electronic is not the magic solution as is generally believed.

Alec

[GeorgeHurst]

Alec, my thoughts exactly which is why I put 'sports' in inverted commas!
I think from their product description it includes a more powerful coil to give a better spark, and the dizzy's electronic bit is uprated to cope with that. Not entirely sure though.
They supply dizzys for Bull Motif I think so I am taking that as my warranty that they are a decent unit, I've also read a few posts on here where people have successfully installed Simon's kit.
Defintiely agree that electronic not a magic soultion and that some of the publicity for them is probably exagerated i.e. better economy and more hp etc, but I like the fit and forget factor and not having to worry about adjusting points

[bmcecosse]

Alec is correct - no vernier on the 45D. The main 'improvement' on the later dizzys is the shape of the cam - supposedly delays point-bounce at high revs. Also 'easy fit' points and condenser - and larger diameter dizzy cap so supposedly less chance of arcing between HT lead connections. Personally - I like the 25D (and have a huge stock of them!!) - and i am not a fan of electronic ignition - although my TR7 came with it - and it has behaved itself v well! I do carry a complete spare dizzy and coil with me at all times - both in Minor and TR7. You can decide after reading the Wizard if you want to adjust the mechanical advance inside the dizzy - would be interesting to ask this 'simon' chap what advance is in the dizzy he sells ! My dizzy has been 'adjusted' to give ~ 18 degrees dizzy advance = 36 degrees engine advance - and this allows me to run the static advance very low for easy starting. It 'just' pinks slightly as I put my foot down - as the vacuum advance rolls off - and then accelerates away without pinking.

[MarkyB]

I do carry a complete spare dizzy and coil with me at all times

A coil! didn't I hear you say it's never the coil?
Except when is is of course.

[bmcecosse]

It's certainly NEVER the coil - if you have a spare with you!

[GeorgeHurst]

Hi all,

I've got a Metro cam which I am putting in this 1275, is there any advantage to putting the 1275 cam that I will be removing into my 1098?

I was thinking of selling the 1098 but seeing the stupidly cheap prices they go for I think it is worth more holding onto it and using it in a project car when I get one. The compression is 150-151 psi on all cylinders so it's in top condition so I'm not going to let it go for 50 squid on ebay!

Presumably I will need to change the oil pump if putting the 1275 cam into the 1098?

Cheers
George

[bmcecosse]

The timing and lift are the same - BUT - they are advanced ~ 4 degrees which BMC discovered gave slightly better mpg, and the cam lobes are the 1/2" wide version which is obviously better than the old 3/8" lobes. Yes - you would need to swop oil pumps - but, the old pump from the 1275 won't fit on a 1098 because it is 'long shaft' and the 1098 needs a 'short shaft'. The old 1098 shaft is a good upgrade for a 948 - and indeed likewise the old 1275 shaft would be fine in a 948 - with the correct short shaft pump of course! Hope this helps!!

[GeorgeHurst]

Cheers Roy, hmmmm, doesn't sound too much benefit though a few more mpg might be good. Probably put it on the slow burner list!