22 replies to this topic

[Ginge620]

Is this about rate for a Kent 266 or is there something else going on. Engine has done like 350 miles.

Bare with I video should come up shortly

Edited by Ginge620, 21 August 2015 - 06:14 PM.

[Ginge620]

Link to video https://goo.gl/photo...VpLGz4TaNT6Xwa8

[KernowCooper]

I have a 276 in my 1330 and its sweater on idle, are you sure the mixtures not to rich at idle speed

[Ginge620]

Well It isn't rolling roaded but I think the colour plugs are good. Maybe a little rich. Pulls pretty well tho.

[Cooperman]

Does it have an ultra-light flywheel?

Might be mixture or timing at tickover.

[Ginge620]

Does it have an ultra-light flywheel?
Might be mixture or timing at tickover.

No, standard fly. May well be ignition timing. I'll check tomorow. I'm right in saying 8-10 degrees is what should be aiming for. Out of interest do you know how advanced ignition timing is on race engines?

[KernowCooper]

A lot would depend on the compression ratio and the fuel used but max would be in the 34deg region

[carbon]

As Kernow Cooper says 34 degrees total timing (static plus mech advance) is in the right ball park, but will depend on your motor. What CR and fuel octane are you using?

 

34 degrees would be 10 deg static for a dizzy with total 24 deg mech advance (ie stamped 12 on the advance cam).

 

In my experience getting the dizzy advance curve right is not a trivial exercise. Details such as CR and valve lift can make a big difference to the curve. Static timing is only part of the solution.

 

I have 266 cam in a 1293 and this needs more than 10 deg static and also using a very light primary spring in the dizzy to get the idle smooth. This one is also using vacuum advance.

[Cooperman]

 

Does it have an ultra-light flywheel?
Might be mixture or timing at tickover.

No, standard fly. May well be ignition timing. I'll check tomorow. I'm right in saying 8-10 degrees is what should be aiming for. Out of interest do you know how advanced ignition timing is on race engines?

 

On race/rally cars there is more total advance available and the basic static timing is usually the same as standard. In fact, with a very high compression engine it may be slightly less. However, the advance curve is changed and can be retarded slightly until max advance is needed at which time there will be more total advance than standard.

As an example, with my 'S' engine which runs a 286 and has 11.1:1 CR I start with 5 degs advance for starting, then I have 4.5 degrees more total advance than an Aldon 'Red'. I think I have 37.5 degs at max power and above 4800 rpm, but the dizzy is an Aldon 'Custom-Curved' one which was done specially for my engine spec.

[Ginge620]

 

 

Does it have an ultra-light flywheel?
Might be mixture or timing at tickover.

No, standard fly. May well be ignition timing. I'll check tomorow. I'm right in saying 8-10 degrees is what should be aiming for. Out of interest do you know how advanced ignition timing is on race engines?

 

On race/rally cars there is more total advance available and the basic static timing is usually the same as standard. In fact, with a very high compression engine it may be slightly less. However, the advance curve is changed and can be retarded slightly until max advance is needed at which time there will be more total advance than standard.

As an example, with my 'S' engine which runs a 286 and has 11.1:1 CR I start with 5 degs advance for starting, then I have 4.5 degrees more total advance than an Aldon 'Red'. I think I have 37.5 degs at max power and above 4800 rpm, but the dizzy is an Aldon 'Custom-Curved' one which was done specially for my engine spec.

 

Thats pretty cool and interesting stuff.

 

As Kernow Cooper says 34 degrees total timing (static plus mech advance) is in the right ball park, but will depend on your motor. What CR and fuel octane are you using?

 

34 degrees would be 10 deg static for a dizzy with total 24 deg mech advance (ie stamped 12 on the advance cam).

 

In my experience getting the dizzy advance curve right is not a trivial exercise. Details such as CR and valve lift can make a big difference to the curve. Static timing is only part of the solution.

 

I have 266 cam in a 1293 and this needs more than 10 deg static and also using a very light primary spring in the dizzy to get the idle smooth. This one is also using vacuum advance.

Im running 99 octane fuel with around 10.2 CR i believe. Also i still have the standard dizzy on which i want to swap out at some point to an Aldon Yellow, i think that should be more suited to my set up.

I did a bit of experiment earlier this week (trying to figure out some knocking noise), playing about with ignition time. I did the "by ear method" (Vac off, turn and listen for idle to increase then back off when miss fire or lower idle) which made i idle easier and smoother, also better throttle response and power at the low end, but i could here it pinking under load so i kept retarding it a bit at a time till it stopped but ended up loosing a bit of power and the idle isnt so smooth. 

Ill play around with it again tomorrow with the stobe light so i can record the results better but for i know maybe theres and issue with the stock dizzy.

 

One last this rather than making another topic, i had the engine where you blip the throttle and the idle drops to the point where the engine would cut out then after a few seconds the idle comes back up. Not sure if thats to do with the dizzy, as far as i know there is now vaccuum leaks from anywhere, inlet manifold, brake booster etc.

Edited by Ginge620, 21 August 2015 - 10:10 PM.

[carbon]

10.2 CR is good for 266 cam. Have you run compression test on all 4 cylinders? You should be getting 200-210 psi when warm. I have a 1330 with 266 and 10.5CR, this is getting marginal. I tried to do a compression test on this one when engine was hot but it diesels (kicks back) after about 3-4 turns. Compression test with warm engine on this 1330 gives about 220-225psi.

 

Lucas distributors have part number on them which can tell you mech advance and advance curve. Normally 5 digits such as 41257.

 

Before setting it all up with custom advance curve, I would suggest deciding if you may want to use higher lift rockers. On my 1293 fitting offset bush rockers made a massive difference to mid and top range, but I also had to completely change the advance curve to make it work at lower range.

 

I would recommend using rockers from 1.3 to 1.4 ratio with the MD266. I am currently saving up so I can fit a set of Calver's 1.4 rockers to the 1330...

[Ginge620]

Took my car into work this morning to do oil, filter and plugs (fitted new plugs because i used the old ones after rebuild). A guy who works there, experienced with classic stuff he had 1380 long time ago, he had a look and tweaked the carb mixture and ignition timing at 1000rpm, did both by ear. Also moved the cam gear clockwise 1 tooth to give easier adjustment because it was hitting the oil pressure line.
Car does run better now, much smoother better throttle response and idles really well. I checked with the strobe light and I'm reading 18-20 degrees @ the crank pully. Not pinking or anything.
I've stripped down the distributor and done a little video, just wondering if the weights and springs look ok?
https://goo.gl/photo...pfaBcboFpyoMKM9

Edited by Ginge620, 22 August 2015 - 02:45 PM.

[carbon]

18-20 degrees at idle is about same as my 1293 with MD266. Sound a lot but with any less advance it does not idle as smoothly.

 

But to get this I am using about 12-14 deg static advance with very weak primary advance spring in the distributor. And this distributor has 10x2=20 deg of mechanical advance which gives me a maximum of 32-24 deg advance from about 3,500rpm.

 

Would recommend checking your static advance and amount of mechanical advance. There is a number stamped on the advance stop plate in the distributor, should typically be 10 or 12 but can be anything from 7 to 17 depending on the provenance of the distributor. Multiply this number by two to get total mechanical advance in crank degrees, then add static timing to give total advance in crank degrees.

 

If you're over 35 total advance then I would be cautious about using this enthusiastically until you get it set up on rolling road.

[Cooperman]

There are so many things which can cause rough or lumpy running.

I did a very thorough restoration on an Innocenti 1300 Export a few years ago. It was running OK before I stripped it and I did a relatively small engine rebuild which included new rings, a light hone, new main and big-end shells, new oil pump and timing chain.

When I was all done, including a fair bit of bodywork & new interior I started it up. Loads of oil pressure, but a nasty mis-fire when the throttle was opened under load. I then did all the usual things like more new points, re-set plugs (which were new), changed the coil, changed the condenser, checked the cam timing again (spot on), changed the dizzy cap & leads from the ones on my 'S' which I knew were fine, took off the carbs and re-checked and set them again (they had been to pieces during the restoration). Nothing cured it.

As a last measure I removed the complete distributor and stripped it right down. It seemed that during the restoration period the bob-weights had become 'sticky' and cleaning them off with brake & clutch cleaner then lightly oiling them with 3-in-1 cured the problem completely. That was a full days work just for a very simple thing.

[Ginge620]

There are so many things which can cause rough or lumpy running.
I did a very thorough restoration on an Innocenti 1300 Export a few years ago. It was running OK before I stripped it and I did a relatively small engine rebuild which included new rings, a light hone, new main and big-end shells, new oil pump and timing chain.
When I was all done, including a fair bit of bodywork & new interior I started it up. Loads of oil pressure, but a nasty mis-fire when the throttle was opened under load. I then did all the usual things like more new points, re-set plugs (which were new), changed the coil, changed the condenser, checked the cam timing again (spot on), changed the dizzy cap & leads from the ones on my 'S' which I knew were fine, took off the carbs and re-checked and set them again (they had been to pieces during the restoration). Nothing cured it.
As a last measure I removed the complete distributor and stripped it right down. It seemed that during the restoration period the bob-weights had become 'sticky' and cleaning them off with brake & clutch cleaner then lightly oiling them with 3-in-1 cured the problem completely. That was a full days work just for a very simple thing.

Quick question regards to the weights and springs. Should there be and slop with weights. The springs don't seem the fit snug, there is a bit of free movement as you see in the second video.