fine tuning

[timwilks13]

Pretty much got all engine orientated stuff sorted, no oil leaks, black smoke etc. My only query now is that i can't rev particularly high, which is no issue in 1st, 2nd and 3rd, but in 4th i can only do about 40-45 and not get the revs up enough to hit 5th. What should i be fiddling and twiddling to get that little bit extra oomph from her? Any tips or guidance (even from you Jordi ) would be great thanks!

[ScottieJ]

Do all the usual things, check plug gaps etc.

Running an SU carb yeah? first you need to make sure you are using the correct needle and spring for your engine http://forum.suzukiclubuk.co.uk/vi ... =13&t=2249

Then run your engine up to temp and check the timing is correct

http://sucarb.co.uk/technical-hif-type- ... ng-general

http://sucarb.co.uk/technical-hif-type- ... ing-single

Don't forget to make sure your dash pot is full to the correct level and preferably the correct grade oil, straight sae 20 weight oil is best and what you'll find in a bottle of SU carb oil.

When adjusting the carb blip the throttle and let is settle between every adjustment.

how to tell that your mixture is right when tuning by ear. Once the engine is up to temperature remove the air filter and use a screw driver to slowly lift the piston 1-2mm while it's idling and listen to what the engine does......

If it stumbles and the revs drop you are too lean so enrichen the mixture. (don't forget to blip the throttle and let it settle)

If the rpm picks up slightly (50rpm or so) peaks and then drops back to idle you are about spot on.

If the rpm picks up and continues to rise then you are running too rich.

I sort of do a combo of the above and also listen to how the engine picks up when you move the throttle, a few quick blips of the throttle and a steady rise etc.

[timwilks13]

cracking stuff Scottie! I put in a new red spring and bdl needle last week, that was the first big change in power. I put about a bottle cap full of 10W30 engine oil in the dash pot. Ran engine up to temp and did timing the other day, seemed about spot on. Ill have have a fuel mix fiddle tonight.

Spark plugs are all black on the end and not sure how old so wont hurt chucking a new set in.

[Jay18]

make sure your ignition timing is spot on aswel, you'll be surprised how much difference it makes when the timing is out, mine was out a bit so I adjusted it and now it flies! I was used to flooring it to get to 40 and after that I was doing the same thing, sticking my foot down and then looked at the speedo and it wa reading 55 lol so it does make a big difference, and you just can't tune it if the timin is out as it just wants to cut out when you get it to idle at 850rpm, one I timed it up it now runs sweet as a nut..

[timwilks13]

is the 413 the same timing as the 410? i did my 410 to 10° BDC, i assumed the 413 would be the same?

[Jay18]

I'm not sure I will have a look for you I'm sure it's on the net somewhere..

[Jay18]

was easier to find than I thought lol

yes it is the same as a 410 engine 10degrees before TDC @850RPM..

[Jordi]

Nah, sod ya!

I'll keep my advice for sharing with people who really don't want it if it's all the same!

[Jay18]

hahaha scottie got in there first lol...

[jibb]

I've just purchased all my bits for my su carb conversion


This thread is brilliant so much handy info so thank you!!!!!


I'm planning to run my Sj on Tesco super 99 octane!

I've got an air fuel ratio gauge with lamba sensor and boss to weld into my exhaust to give me a good idea of the correct mixture!


I've heard I need to advance the ignition timing more than 10 degrees as it needs to fire earlier for the fuel!
I've also got a adjustable advance timing light but on my 1.6 8v vitara engine the crank pully doesn't have any marks to find tdc. Is there a mark on the flywheel?


Thanks for any help!!!