I have R1 carbs on a 1800 Zetec Silvertop, running megajolt (with 2l cams to go in it). What is the best way to approach tuning it? Where do i start, there are so many variables to consider? I dont really want to take it to a rolling road because i'd like to see what effects my actions have on the engine performance. Also, i dont have the money at the moment to do it! I was thinking of using a G tech pro, how does everyone else tune their car locost style?!

What tools do i need? Air/fuel meter, timing disc etc. When fitting the new 2 litre cams, shall i change the pulleys for vernier ones so i can set those up aswell?

Any advice on previous experience will be greatly received!!

Chaz

You could buy a few drills to change the jet sizes!

you could buy a wide band lambda sensor and controller and with appropriate software data log the mixture into a laptop to keep tabs on your progress.

this would cost about £125 - £150??


http://cgi.ebay.co.uk/Innovate-Motorsport-LC-1-Wideband-Controller-UEGO_W0QQitemZ230126090408QQihZ013QQcategoryZ72205QQssPageNameZWDVWQQrdZ1QQcmdZView Item



[Edited on 10/5/07 by Surrey Dave]

What is your engine worth ? just pay to get it set up on a r/road they have the right gear to do it .
It only cost me £60 at bogg brothers last year its worth it in the long run
Jacko

bogg bros do a good deal , you dont get much rolling road tuning for £60 down south!!

Chaz

It will be interesting to see what MJ settings to come up with, i'm just about to play with my 1800 zetec with fireblade carbs on and i've got 2 litre cams to go in as well.

I'll let you know how i get on with the base cams, i'll be having a fiddle over the weekend as i have the MOT next week

I know, i've just moved down south - bummer. Bogg Bros made up my carbs and manifold, sterling job.

Again, really new to tuning stuff, what is this wide band lambda, isn't it a sensor that fits in your exhaust? What readings does it give you?

Bob, keep in touch i'd really like to know how you get on!

Newark is not far from Boggs

Newark isn't, but i'm not there anymore! Thats where my parents live.

What do you tune first?

Megajolt?
Fueling?
Cam Timing?

Is it just trial and error?

If you mean "in principle" then its an iterative process.

Basically get it running a safe mixture and sensible ignition timing at a first stab peak power revs and full load, with initial cam timing, then swing the cam timing to get a peak power, while checking the fuelling is still safe.

Then, map the ignition finely while checking the fuelling stays safe.

usually at this point, according to the law of sod (and if you were running injection which you are not! ) you will find a chunck of extra power which will need the fuelling increasing, and then you find you have run out of injector time and you have to increase the fuel pressure, thus having to start again on the mapping

PS nothing is cheaper than a decent rolling road and operator who knows what they are doing

I reckon thats right, Boggs did my carbs and manifold as well and i would think its worth me taking time out to pay them a visit on there RR.

You got timing wheels for the cams? If you are only reving it to 6500 yo will need to alter the inlet cam because you get nothing low down otherwise. I cant remember if we advanced or retarded mine but it was 3 degrees for best result. I found you get nothing from changing the exhaust.
Steve.

I'm using the MAP that came with the Megajolt disc. It's the one for twin webers and 1800 Zetec. It seems to work well.
I am interested in what other people are using for this set up.
1800 Zetec, Fireblade carbs with 160 main jets, ITG megaflow filter and Megajolt.
Bill.

If you are doing it Locost style I wouldn't bother with vernier pulleys. The standard pulleys are not keyed so can be adjusted to suit. I bit more fiddly than verniers but a worthy saving.
Try to borrow a wideband (I know you can hire then somewhere) to get a rough idea of your fuelling. Adjust this somewhere close before going for a rolling road tune as this will save you lots of time.
Altering cam timing will just move power up/down the rev range providing it is within a few degrees so won't give you an all over improvement.

The cheapest tune will be 2.0 cams, a bit of work on the valve throats as they are not good as standard, skim the head to raise the compression and a good tubular exhaust manifold.

Basically anything that helps it breath better so ensure you don't have any restrictions. Ram pipes on the carbs helps quite a bit and don't use sock filters as they strangle the flow.

I played with timing on my MJ and used a steep hill as reference point for pinking increasing slightly each time. Plenty of advance in cruise areas at part throttle.

The fine tuning of this is best left for rolling road which will always be the best money spent on tuning as it will get the best out of any other money you have spent.