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5door_racer
03-06-04, 09:13 PM
I have a 1300 mk1 5 door. About a 1000 miles ago got head ported and polished, skimmed, high lift valves, piper 285 cam etc. i also fitted twin 40's. got it rolling road tuned and the tuner said the vacuum advance was broke so i am running the car without it.

What is the best way to go?

I was going to buy another standard dizzy but what other options are there and are they worth the money?

i have also heard of people modifying the vacuum advance but don't know what this invovles.

I am getting 95bhp at the flywheel and 78bhp at wheels but feel there is a lot of power left if set up properly.

Any help would be much appreciated.

cheers, tim
johnny27
04-06-04, 07:07 AM
According to what i've heard on novaload, when your not using the vacum advance make sure to seal it off, advance timing by 30 degrees. Thats the way i done mine, and i have no problems at all.
david dixon
04-06-04, 05:51 PM
You can buy 2D and 3D ignition systems which give you the best spark you could ask for, most can be easly remapped if you change the spec of the engine, the limiter is also adjustable on most systems, these can help hike the power on high powered engines where distributers wont take that much hammer.
MechaT
04-06-04, 09:27 PM
You can buy a new vacuum unit from a Vaux garage. Think it cost me 15 quid. I reckon if you can afford it then get mappable ignition. Bob weights do the job but it's no good for proper performance motors.
Stuart
04-06-04, 09:38 PM
?15 fooooook


i Paid ?45 for one for the delco type dizzy back in 1999 lol



most dont run the vac advance as you'd need to tap into all 4 T40 branches.
Dan
04-06-04, 10:21 PM
my gte doesnt run the vac advance unit, just left alone, and never had any probs
MechaT
05-06-04, 01:13 AM
my gte doesnt run the vac advance unit, just left alone, and never had any probs

Yeah to be honest I couldn't see the differene with it on or off on my SR.
What do Sports do about vacuum advance? Do they not use it either?
m.d.
05-06-04, 10:16 AM
if your running twin carbs you dont need the vacum advance at all. just disconnect the pipe from wherever it is on the carbs and block it off with something. then just throw the rest of the pipe away. get it tuned again and your sorted. if the tuner tells you that you need it then tell him to bugger off. with the cam you are running the advance would do sod all anyway.