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Technical Board => General Technical => Topic started by: Dave_EH on February 26, 2005, 09:25:07 AM



Title: Tuning SUs?
Post by: Dave_EH on February 26, 2005, 09:25:07 AM
Hi all,

Just wondered if anyone had a document that has been scanned or otherwise they could email me that documents how to tune SU carbies?  Or is there somewhere online?

I've finally swapped mine with a mate, so we are going to bolt them on sunday arvo...

A long shot but worth a try.

Regards
Dave


Title: Re: Tuning SUs?
Post by: Shayne on February 26, 2005, 09:57:28 AM
Gday Dave,

courtesy of the Morris club of Victoria.  Try this link:
http://www.moreg.org.au/carburettors.htm

if you are chasing more info, try typing "tuning su carburettors" into a search engine.

regards, Shayne (recently promoted to 'Guru', in title only, not nature)


Title: Re: Tuning SUs?
Post by: normd on February 26, 2005, 04:29:18 PM
Hey Dave
     How Many SU's ? ,   Might be worth a chat with Craiga also , (hope he don't shoot me for this  :-X)  he's had experience with triples from his torana days ... (strombergs I think) but the principal should be the same.

    Norm  :)


Title: Re: Tuning SUs?
Post by: Dave_EH on February 27, 2005, 03:59:45 AM
Thanks Norm,

They are triples... I just took them down to a torana performance place we are friendly with and he gave them a quick look over.  He thinks they should run alright... but said you should get an SU guru to set them up properly.

A mate is going to lend us his vacuum guage, so we will have a bit of a fiddle and see how we go!

Cheers
Dave


Title: Re: Tuning SUs?
Post by: Dave_EH on March 01, 2005, 04:48:28 AM
Thanks for the help guys.

It seems there must be a major variation in the stud location on holden red six cylinder heads!  We took off the holly, and the manifold for the SUs wouldn't go close!

After some hours with a steady hand and some rolling stones we managed to shave a little off the manifold with an angle grinder to enable the bolts heads clearance to screw in, as well as taking a little off the stud recesses and a heap off the little jackets that pull tight on the manifold!

We were't sure where to plug the vacuum advance or how to rig up the cold start, so it was fuel lines in and fingers crossed...

Holding the throttle open by hand (need to make a cable bracket up) while one of the boys held the started motor on and after about 30 seconds of sucking fuel into the lines she started up.

A nice even idle from a cold start, smooth through the rev range and a magnificent sound of 3 SUs sucking in fuel!!!

Big smiles all round :P

Dave


Title: Re: Tuning SUs?
Post by: craiga on March 01, 2005, 06:06:55 AM
Dave,

Couple of tips - get your hands on a die grinder and take the time to match port the SU manifold to your inlet ports, it makes a huge difference. Even go as far as to match port the carby to the manifold.

Also make sure your manifold gasket , I would guess you are using an 'extractor' type gasket, is also match ported. Also spend LOTS of time on making sure the linkages are set to open evenly across all three carbs.  You can buy a special carburettor synchronisation tool for this purpose. About $80.00 but worth every cent if you own triples, ESPECIALLY SU's  ;)

Enjoy the music from those three suckkers.

Cheers,

Craig.