Thread: weber 32 / 36

Originally posted by Michael2

I was hoping for better economy, I thought I'd be able to cruise around on the smaller barrel, then open it up for power when needed. I suppose that will depend on how much power comes from the primary, and how I modify my driving style.

You are right - in theory you should get better fuel economy - the primary throat is normally quite small - like having a little carby so fuel usage should be reduced. If set up correctly the second throat should only come on line when needed ie high speed and full throttle. The tyres I had on my subie were much wider, much higher and the wheels were an inch higher and wider - so it was like a landy with big wheels - so it needed a boot full of juice to perform. I also had a cam grind and extractors.

My experience with extractors and a big exhaust on my series 3 landy engine was extremely positive so I would think about these mods - as far as the cam goes will depend on what you want - for me the series 3 already had good low down power but ran out of puff at the top end - so if you are happy maybe a cam that does this might be the go for you - if so make sure that if you do a cam grind you don't loose at the bottom end.

I also put on a dick smith basic electronic ignition system - didn't change performance but did mean the car stayed in tune longer.

Gazz

Gaz, we're on the same wavelength.

8) I've got extractors with a slightly wider exhaust.
8) I've had a cam regrind. All valves open 5 degrees sooner and close 5 degrees later. This has made a huge difference.
8) I'm using a higher compression head.
8) I've fitted Pirhanna electronic ignition.
8) I've fitted an overdrive.

So I hope the carby brings it all together.

There is a mod you can do which improves the hill climbing ability.
There is a vent from the float chamber into the throat between the two venturis. You araldite this up and stick a small tube in it so it protrudes as far as possible without fouling the air cleaner. the climbing problem is caused by fuel spilling out this vent on steep hills into the throats. If you look at a Holley off road carb, they extend the vent and bend it over and put pin holes in the top.
I have one at home which I bought for a Vitara which I have so cannot help with the jets.
I will swap it for a Holley 180 if anyone has one. Same carby, linkage on opposite side!!!! Vitara has carby on RH so linkage goes straight into the rocker cover.
regards Philip A

Originally posted by garrycol

I also put on a d**k smith basic electronic ignition system -
Gazz

Oooohhh Wahhhhh - the censorship nazis got me - could understand if I said dick head, or xyz is a real dick or you get the drift - but someone's name - I appreciate it is auto generated but what if my name was Dick - I don't think I would like to be called DblipblipK all the time.

Hey - how many Dicks we got out in AULRO land anyway.

Gazzz

Thanks for that little tip Philip, I'll check it out when I get the carby back, it's with the guy modifying the inlet manifold at the moment.

The 32/36 is now on the Landy. Here's the story in point form.
8O I had a 1/4" alum plate welded to the top of the inlet manifold.
8O I used holes saws to cut the 32mm & 36mm holes through the plate and into the manifold, & drilled & tapped holes for the mounting studs.
8O The holesaw holes went through the side into the exhaust gas chamber. - not to worry as I'm using extractors & not an exhaust manifold.
8O I made some liners from alum flashing and used metal putty to block the vents & the bottom of the manifold where exhaust gas enters (when used with exhaust manifold).
8O I started the car up & it ran easily on petrol & gas.
8O The metal putty filler blew off several days later. Massive vaccuum leak. I pulled the manifold off & had the vent holes welded up. I noticed that one of the sleeves I'd made was missing. I checked the inlet valves with the manifold off and they were all clear. I removed the plugs and spun the motor, all clear. I'm guessing thin (<1mm) alum would have compacted & melted without doing any/much damage.
8O I reassembled it again today.

There's not much more power, a bit brisker on take off and holds 100kph easier though. There's what sounds like a tappet noise only when the motor is hot. Frequency seems to match tappet speed. I readjusted the tappets, ran the motor with the rocker cover off, but the noise was still there. :?: sticky valve :?: The tappets were OK, the noise appeared with mild acceleration with/out load.

Timing is OK, the mixture was a bit rich and I'm not sure if the jet sizes are too big (160 primary, 170 secondary). Dyno tuning is a bit expensive, so a mechanic mate suggested I put an O2 sensor on the exhaust and get a $15 kit from jaycar which analyzes it. Then I can tune it better, and being road tuned the motor will respond more realistically than on a dyno. The dyno will get me heaps of advance with speed, but not offset this with driving load.

Hopefully hill climbing will be better once this is tuned.

Originally posted by Michael2
There's what sounds like a tappet noise only when the motor is hot. Frequency seems to match tappet speed. I readjusted the tappets, ran the motor with the rocker cover off, but the noise was still there. :?: sticky valve :?: The tappets were OK, the noise appeared with mild acceleration with/out load.

I don't know your engine that well but from the description.... hmmm.... how much lift is on the cam you installed?

First thought is valve springs. Bigger lift cam and/or weak (standard) valve springs could cause symptoms similar as there is less control. So instead of following the backing ramp of the cam, the valve holds open (weak spring) before pounding into the seat. So maybe a set of performance valve springs and lockers (collets) is the solution ?

Second thought is the hydraulic lifters aren't pumping the oil fast enough to maintain pressure within themselves. So that could be the lifter itself (valve system within failing) oil type, oil feed/overall oil pressure.

All I can think of straight off without more info or listening to the engine. [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img]

I used the standard cam, just ground it to provide wider openings. I don't think this would affect lift - but I'm no expert on their operation.

Could be oil pressure related, oil pressure drops to 20 from 60 once the motor is hot (@idle) the warning light doesn't light at that pressure. I'm going to replace a leaking sump gasket this week and will replace the impellers on the oil pump and see what that does. Otherwise I could try HPR 40 or a litre of Moreys 8O

The oil is Penrite HPR Gas and has just been replaced. The noise was there before / after the oil / filter change.

The noise may have been there for awhile, but not heard due to a small exhaust leak (that got to be a big exhaust leak). Now that the extractors are quiet I've noticed it.