4 cyl motor

[antvc]

Hello All

I have a 109 Ser2a 4 cyl with a new weber carby fitted and am now on unleaded fuel. I have changed the spark plugs to BP6ES as suggested for unleaded fuel. The car starts well and runs well but when on the highway and starting to go up a small hill the car looses speed very quickly.I don't think it should be this bad as when the holden carb was on it seemed to run better.(was using lead fuel then as well) I was thinking that the engine is not tuned properly or the carby might need new jets.
Would using premium unleaded make a difference?
Has anybody any comments or suggestions.

Also i recently fitted parabolic springs and new shocks. The car defnitly rides better on the dirt roads and I am happy with the conversion. I only had a problem with one rear spring getting the bolts out. They had rusted to the bushing sleeve.

[shaunp]

Lean under load perhaps.

[fernockulated]

Originally posted by shaunp
Lean under load perhaps.


to the left or the right??? :?





sorry , couldnt resist that one ! :oops:

[antvc]

Thanks for the comment.
If it is running lean do you know the adjustments on the carby to correct it? Or something else I should check?
The fuel economy is about 16mpg so I don't think it is too lean.

[Michael2]

When I converted to ULP I had trouble getting a smooth idle. I was told the advance curve on the dizzy was too much for ULP and had the dizzy reweighted. Apparently the Land Rover has 30+ degrees of vacuum advance, which is too much for ULP. I still lose power going up hill. I've put the bosch 4 pronged spark plugs in and these made a noticable improvement (though they made no improvement to the Rangie), I've also added electronic ignition, no power boost from that, just for reliability. I've also removed the fan and run an electric fan on thermatic switch. I found that gave the motor more flexibility (pep) at 80-100kph. I'm now running LPG most of the time, so that puts a slight damper on performance, but gives the wallet a performance boost.

Which parabolics and shocks did you go for? I've used british springs paras with konis on the rear and rancho on the front.

[antvc]

Thanks for the reply Michael2.
My paras are Rocky mountain and explorer shocks. I have only had them on a few weeks so haven't had a real test of them but they are much better on the dirt roads.
As for the engine , I was wondering about the dizzy and the timing, I might try a few different settings to see what happens and try premium ulp to see if there is a difference as well.
Anybody had experience with weber carbs and the jet sizes?

[antvc]

Forget to mention...I have an electronic ignition kit from dick smiths which I made up to fit.I have tried it and it seems to work but it is not on at the moment. Need some more time to fit it permently.

[antvc]

I thought I would update what I have done so far to check the tuneup of the motor. Compression test about 125 psi per cylinder, timing at 6 degrees, idle at 800 revs and checked the settings of the idle and mixture screws on the carby as per the instructions. The mixture screw was set was too rich. The car seems to be running better but need a few more miles to check it and get a better idea on the fuel use.
On talking to a person who has some experience with webbers, he suggested it might be worthwhile to change the emulsion tube to a slightly larger setting and try it. It would be helpful to use a dyno with a few tubes and jets to try on hand. but at the moment it seems to be o.k. so will stick with this
Anthony style_emoticons/<#EMO_DIR#>/smile.gif

[antvc]

And, anyone happen to know what the dwell angle should be for the 4 cyl motor?
Thanks

[UncleHo]

Hi Antvc, style_emoticons/<#EMO_DIR#>/smile.gif
Here are some specs for 4 Cyl 2.25 3 mainbearing motors, pre anti-pollution ign timing was
7:1 Comp = 6 Deg BTDC using 90 Oct Fuel (ULP 91)
= 3 Deg BTDC using 83 Oct Fuel (old standard)

8:1 Comp = TDC using 90 Oct (ULP)
= 3 Deg A T D C using 85 Oct Fuel (old standard)

On engines fitted with anti-pollution devices the settings are,
7:1 Comp = 6 Deg ATDC using 90 Oct Fuel.

ALL READINGS TAKEN WITH VACUUM TUBE DISCONNECTED
POINTS GAP 0.014--0.016th (0.36-0.040mm)

CRANKSHAFT ANGLES: Engine RPM
38*--42* *= Degrees 4500
30*--34* 3500
22*--26* 2500
12*--16* 1200
04*--12* 900
00*--04* 600
Nil below 450

Plugs Champion N8 = 7:1 or UN12y = 8:1 GAP 0.029-0.032 th (
0.75-0.080 mm)

Cheers style_emoticons/<#EMO_DIR#>/biggrin.gif

[Hellspawn]

I did read somewhere how to work out dwell by the contact gap. For every 0.10mm of gap the dwell angle moves xº depending on which way the gap moves. The basic principle is to increase dwell, reduce contact gap and increase contact gap reduces dwell.

I do know 0.50mm gives 52º so with what rocket has shown, my guess is if the contact gap is 0.35~0.40mm dwell will be somewhere around 54~58º between idle and 2000rpm.

I think the most important thing with dwell is how much variation between idle and 2000rpm rather than exact figures. Variations show either worn dizzy cam, excessive side play in the shaft or crook contact set. If the contacts are set correctly your dwell will be shown with it idling and will stay fairly uniform up to 2000rpm. If not the further inspection is required.

[antvc]

Thanks for the info. The dwell is about 62 degrees on my engine so maybe the points are a bit to close. But the engine sounds like it is running well so will leave things for the moment.
Anthony

[incisor]

found on a forum faq in england somewhere...

Q. What is my Series Land Rover distributor’s dwell angle?
A. 60 degrees + or – 2 degrees

[LandyAndy]

Hi Anthony
When you run the LPG,you can advance the timing more without pinging as the LPG has a better rating than the old super RON,with the LPG you should go the next heat rating DOWN (ie cooler) than standard as LPG burns hotter.
Cant give you the exact increase in advance over standard on my 202 as it appears to have a mismatched timing cover/harmonic balancer.
Once you work out where your landy runs best on LPG mark the dizzy against the block,and also a mark for where petrol works best.It is then just a matter of a quick adjustment to suit the fuel you are running.
Premium ULP should work out the same or better value as you should use less than ulp per km,unless you really get stuck in with your right foot with all that extra power!!!!
Andrew

[Hellspawn]

You mean points are too far open..... style_emoticons/<#EMO_DIR#>/biggrin.gif