Wanted: Round top SU's to suit L24 with E88 head.

[luke240ZED]

Hi Guys,

 

I'm looking for a set of round top SU's and manifold to suit my current L24 with an E88 head.  I currently have triple 45mm webers and I am looking for a more streetable setup.  Don't get me wrong, the webers are a lot of fun but only come into their element at high RPM.  Looking for a bit more lower RPM power to make commuting a lot more pleasant.  My webers will just take a back seat for an L28 build further down the track.

 

Cheers

Luke

[260Coupe]

Maybe try installing smaller chokes and retuning the webers..........there should be no reason why the tripples could not be made "streetable"

I run 44 Mikuni's with 32mm chokes on an L26 are they are like fuel injection on street car

 

Al.

[pauly_adams]

i must also agree putting on su's will not realy benafite your setup that much, it mainly to do with the tune, my L26 with su's never came into play until about 3k rpm then it was ballsy as, my efi is the same aroud 2500-3000rpm i get decent power. the only carb that was good for down low torque was my 350 holley but it was terrible in higher rev range and used alot of fuel on highway driving.

 

hope this helps

[luke240ZED]

Thanks for the input guys.  I currently run the following on my 45 DCOE's:

 

160 Air

130 Main

F11 Emulsion

50F9 Idle

45 Pump

32 chokes

 

With the cam it really sweetens right on the 3750RPM mark and launches nicely from there.  Under that is pretty rough.

I'll have a look at the timing again over the weekend, re-tune, balance the triples again and see where we get.

 

Cheers

Luke

[luvemfast]

Those jets sound about right.

Maybe your cams the issue. What grind is it? Clearly not stock?

[luke240ZED]

I have no idea what grind the cam is.  The cam from what I'm told is about a stage 2, but this was when I bought the car. 

 

1. Can I take the rocker cover off and measure the lobes somehow?

2. If I move down in cam sizes, will I lose much power or will it just shift the range?

 

Cheers

Luke

 

[chris240]

Luke your recipe is 100% spot on.......for 40mm webers !

Im running almost that exact recipe with 40's on my L28.

Its not the preffered thing to do, that is to down choke and down jet a 45mm when the books will tell you a 2.4 litre engine is better served by 40mm tripples. Im talking about mild engines here not Peter mac monsters 

[260Coupe]

I have no idea what grind the cam is.  The cam from what I'm told is about a stage 2, but this was when I bought the car. 

 

1. Can I take the rocker cover off and measure the lobes somehow?

2. If I move down in cam sizes, will I lose much power or will it just shift the range?

 

Cheers

Luke

 

If it is a regrind it should have a number stamped on the end, you may have to remove the cam sprocket to check.........you should then be able to google the specs or check any of the cam grinder's web sites (Wade's, Camtech etc)

The other option is to use a dial indicator to measure the lift and duration but this is quite a complex exercise

 

......or you could try a stock 240 A grind cam and see if that improves the drivability

 

Al.

[luke240ZED]

OK so today I performed the following:

 

1. Set timing to 15deg idle which gave me 32deg at 3000rpm (17deg mech. advance) and it started to drop off in power around the 5000rpm mark with a few coughs and misfires.  So I retarded it back to 12 deg idle which gives me 29deg at 3000rpm (no vacuum).  This seemed to be quite nice with no issues.

2. Re-tuned the webers and all 6 throats balanced and set for a smooth idle around 900-1000rpm

3. Reset and adjusted all accelerator linkages to the webers

 

Final result to give you an idea:

 

 

Cheers

Luke

[luvemfast]

So one can assume, you're happy now?

[luke240ZED]

Sorry, yes, all seems to be in good working order now.  Not sure if it was the timing or the carb adjustment but it's running quite well.  I had not done the timing since the pertronix install so that could have made a difference.  Still curious to the cam specs but that can wait until another weekend.

 

Thanks guys

Luke

[luvemfast]

Did you take it out for a drive to see how it went under load?

 

[luke240ZED]

Took her out for spin today and all is well up until about 5000rpm then power started to drop away.  I was a bit perplexed as the timing wasn't too high wondering what could it be.  I went back to square one and checked the compression stroke of TDC would line up my dizzy rotor to 8:30 but I must have been a couple of teeth away so I dropped the oil pump out, moved a couple of teeth around to line it all up to 8:30 position and reset all the timing.  Set the advance to 34deg this time which gives me an idle of 17deg.  So far the engine seems very responsive but I didn't get time to take her out for a load test on the road.  Will need to try that after the rain goes away or things might get a bit hairy.

 

Cheers

Luke

[luvemfast]

I was actually thinking you need to go up on the idle jets

[luke240ZED]

I bought a set of 55F9 idle jets after a dyno run a while ago as the guy said it may just fill that early range.  Nope, they ran so rich I hardly made it around the block.  I've got 1 1/2 turns out at the moment with my 50F9's which seems to give it that smooth idle at about 900rpm.  All this tinkering has got me on a roll so I might fit the 55F9's again and see if I can make them work with all the changes.  I'll let you know.