Dirk

My car never had a CAT nor does it have a smaller filler. But what I am trying to achieve is a smooth and happy engine. Lower ocatane fuel in my case does not allow for this. I'm sure I am not the only one with a GEN 1 soob that has found this to be the case. And ofcoarse the engine is no longer stock. But then no 30 year old engine is going to be.

I understand. But what do think of the Vac method for setting base timing?

Hey Noah, Thanks for the feedback. Indeed New Zealand was a late starter with unleaded fuel. The reduction of lead in fuel started in the early eighties. Leaded fuel was only made ilegal to sell in this country in Sept 1996! However I still think that my comments are relevant to US engines produced before 1980. This would more or less exclude the EA81 but still include EA71s and earlier. Do you think this is fair? I chose the vacuum method of timing since it has been most useful to me. Particularly since my timing marks are incorrect. Are you suggesting that this may be too advanced for the engine to be reliable?

Carb tuning. This notes are based on Hitachi carbs and assume optimum timing. Idle jet: This can be fine tuned via the idle mixture screw. Consider the screw to be like a shower mixer. Turn the screw too much in either direction and the mixture will be incorrect. ( too hot, too cold/ too lean, too rich) If you are able to turn this screw fully in one direction then it is likely that you have the incorrect idle jet. Fully clockwise means the jet is too big. Or the needle at the end of the screw is worn r damaged Fully anticlockwise means the jet is too small. The idle jet is just that. It has a small influence at part throttle but less and less as you open the throttle more. It can NOT be used to compensate for incorrect main jets. more to come...............

Notes on fuel ratio. I will start with another preface. I have been working on the same engine (EA71) in the same car for the last 4 years. In this time I have taken almost as many steps back as I have forward. But slowly after much reading and even more experimenting the engine is running smoother and with more power with each step forward. What I mean to say here is that I do not believe that even with the most knowledge and equipment at ones desposal is it possible to perfectly tune an engine first time. The concept of making one change at a time is a good one. However one must not forget that this single change will affect many other aspects of the engine that may also need adjusting at this time in order for the change to take effect in the desired way. For example: Making changes to fuel ratio's will not change the base timing of the engine BUT it will affect how the fuel mixture is burned. So..... 'Richer' fuel mixtures tend to igite reliably and also more quickly. This means that you are getting one big bang very close to the moment of ignition. This means that you may be able to afford slightly more advanced timing...... 'Leaner' mixtures can be less reliable and also take longer to burn. This can lead to pinging as flame fronts collide with each other in the combustion chamber. The longer burn time can have the EFFECT of retarded timing. If the mixture is too rich then the combustion chamber and spark plugs can foul up. Dirty plugs will cause eratic igition. Carbon deposits can cause hot spots to pre-igite or ping. Carbon buildup can also increase compression ratio's and compound problems. This is an interesting situation since your spark plugs may be telling you that the engine is runnning rich or too cool but the overheating and pinging is telling you that the engine is running too hot. Care in diagoses is important. If the mixture is too lean the combustion chamber temperature will rise and a over hot plug can again cause pre-igition. Sharp edges in the combustion chamber can also heat to the point of pre-igition. Back to timing again. As I have already pointed out, Different fuel ratio's will affect the burn cycle. If you think that your fuel ratio's are about right then you can fine tune the burning cycle and indeed the colour of your spark plugs by adjusting the timing. Advancing the timing tends to brighten up the plugs a little. Retarding the timing tends to dull them up. If you have to adjust the timing well beyond its perameters then it is likely that your fuel ratio's are incorect. The reverse of this procedure can also be adopted. If you are happy with the base timing of the engine then you can fine tune the fuel ratio's to suit.

Before I start on this I should point out a couple of things. 1. Everything I am about to write is based on much research a little experience and what has worked for me. I have read through many articles about this subject and used many sources to form MY OWN understanding. If it is incorect then I welcome constructive critisism and ideas. 2. Disconecting or tampering with emissions devices may not be legal in some parts or may lead to failure of emissions inspections where you may live. It would be prudent to find out before making the following modifications. 3. Even if there are no legal emissions requirements in your area you may wish to consider the environmental implications of removing the following. 4. Sorry about the spelling. And so... Uleaded fuel became mainstream in most countries in the mid 80s. Therefore we can assume that cars made before this time were designed to run on leaded fuel. EDIT: This is a big assumption and not neccessarily correct depending on where your car was born. However it has been bought to my attention that any car with a factory CAT would have been designed for unleaded fuel. That said, it would appear that the quality of fuel has changed somewhat over the last 30 years and therefore some aditional tuning may still be to the advantage of older soobs regardless of what fuel it was designed for at the time. END EDIT. Leaded fuel had an octane rating of about 100 RON. Todays pump gas has a maximum of about 96 RON. NOTE: High Octane fuel DOES NOT GIVE MORE POWER!!!!! Infact todays high octane fuel has less btu's than lower octane fuel. However, High octane fuel is more stable and burns slower and more fully. This is the bit we are interested in if we are to have a happy little engine that does not knock or ping. High performance engines require higher octane fuels because the engine compressions and temperatures are so high that lower octane fuels will spotaneously combust before time. The EA engines are not performance engines but they do have a relatively high compression ratio and as I have already pointed out they where designed at the time of higher octane pummp gas. EDIT: Disregard last sentence. END EDIT Also there are other factors to consider with an older engine. Mine has been re-built a couple of times and the heads were skimmed on each occasion. Therefore the compression ratio has been further increased. If your engine has never been re-built then it is likely that carbon deposits in the compression chambers have naturally increased the compression ratio. These carbon deposits can also invite hot spots that can lead to pre igition. EDIT: Also, general wear and tear over the years will have taken its toll on some of the hardware. The carb may be leaking air causing a lean out. Jets may also be glazed causing lean out. Aged distributors wil not help our cause either. END EDIT SO WHAT CAN WE DO TO HELP? 1. Using the highest octane fuel available is a good start. 2. Adjsuting the timing accordingly will aslo help. 3. Add more fuel TIMING. EDIT: 8 degrees is a good place to start but 'optimum' base timing is going to vary from engine to engine. Also it would appear that Timing marks on the flywheel are a guide at best. They are not necessarily bang on. END EDIT The following is in my opinion the most reliable way of achieving optimum base timing. Hook up a vacuum gauge to the inlet manifold and run the engine up to operating temperature. If you don't have a vacuum gauge I strongly reccomend getting one. Mine cost me all of 10 dollars and has taught me a lot about my engine. wind down the rpm as much as you can and then start to advance the timing and watch the vacuum increase untill it will go no higher. This is the point at which your base timing would have been optimal for leaded fuel. Now retard the timing by one inch of vacuum. This should set base timing to allow for todays premium pump gas. Now, go for a drive and see and hear how it runs. You may have to retard 1/2 or one further inch of vacuum. MORE FUEL. Having adjusted the timing it woulod be a good idea to keep an eye on the spark plugs. If at this point they are uber white I would reccomend increasing jet sizes in the carb to richen things up a bit. This will reduce the combustion temperatures which will help reduce pinging and may also afford you a little more power. It may be interesting to note that pinging is more likely to occur at stoich fuel ratios and also that petrol egines produce maximum power with 10% rich fuel ratios. Therefore you have nothing to lose by doing this. DISCONECT VACUUM ADVANCE........... Having done all the above to my EA71 had a happy smooth running engine with pots of power through the rev range. And yet I was still haunted by slight pinging under light load at low rpm. I desperation I dissconected the vacuum advane and.......VOILA! No more pinging AT ALL. So what is it that I have done? and what does the vac advance do? Well, it would appear that under light throttle the vac advance was advancing just too much for the engine to cope. The mechanical advance in the distributor takes care of the advance timing requirement through the rev range. Vac advance is connected via a port on the carb. This means that at idle the vac advance is not active and nor is it at wide open throttle when there is little no vacuum present. The vac advance is most active when cruising under light load and partial throttle. Its job is to ensure a fuller burn thus reducing emissions. Essentially this is all it is. An emissions controll device. Although I am told that it also aids fuel ecconomy. In any case it is obviously has a negative impact on my engine under these circumstances. LASTLY These procedures have worked well for me. Depending on the setup of your own engine they may or may not be of benefit. But I hope at least that it has been an interesting read. I guess that a re-curved distributor would be a more perminant solution however this is finance permitting. Right now finance does not permit! I will keep you updated with notes on fuel ecconomy. Regards Dirk.

+1 on checking the timing. Also could be the accelerator pump on the carb and/or a clogged idle jet. No amount of carb cleaner is going to help you if the jets are clogged. I would suggest removing and cleaning the jets. You need to remove the top of the carb for this. Be sure to take care not to damage the gasket when you do this. A carb re-build kit would be handy but in my opinion not essential at this stage. My recomendation would be to service and tune the engine as best as possible (getting to know the animal) before upgrading or modifying. cheers Dirk.

I'm gonna get shot for suggesting this but........ If I wanted a bomb proof go anywhere 4x4, my weapon of choice would be a Jeep Wrangler or Nissan Safari. Ill get my coat on the way out........

Crikey! Thats quite a complex setup you got going there. Those small vac hoses coming off the front of the carb, where do they go? With any luck one should go to the distributor and one to the vac secondary? As for the others, I have no idea. But they should at least be plugged. Was this car running when you got it?

That will teach me to open my mouth to soon. The casting is indeed the same as EA71 heads although I can see now that the valves and combustion chambers are smaller in accordance with the smaller bore of the EA63. + one for Q-man Dirk

Not sure what the E63 is all about but I'm certain that is a EA71 Head. Dirk

Hey. If there is a vacuum hose hanging off it then it needs to be plugged back into a vac port on the carb. If there is no vacuum hose or any sign of ports then you find that the diaphram gets its vacuum signal from the body of the carb. i.e. the vacuum port is part of the diaphram mount. Ta

I think it' a brilliant idea! I can't see any harm in you trying this one ur self. Rocker cover- two bolts Rocker assembly- Two nuts Head- 7 Nuts You will ofcourse need a torque wrench and yes you will have to re-set the valve clearances (not sure if you have hydraulic or solid lifters(if you have hydraulic lifters there will be a sticker on the rocker cover saying 'not not adjust')) Deffinately read the haynes before you start.

I know what you mean. There is simply not enough space in the engine bay to do the job properly. Also on the EA engines you have to remove the rockers to access all the bolts. Last I did it on my EA71 I removed the engine mount bolts and shifted the engine about to gain better access to the head bolts. Dirk

Not sure. I read it in Larry Owens book. But it makes sense to do this on any head with new gaskets. Dirk

Hey Paul. Way past ur bed time isn't it? Laminated glass. In NZ the orifional toughened glass will not pass a 'warrent of fittness' Not that any mechanic normally checks. I had a stone shatter my origional windscreen and the result was quite spectacular. Thousands of little glass pieces. Laminated glass does not shatter. It only cracks. Cheers Dirk.

Dunno but it sounds pretty terminal. Maybe (and this is a total guess) if water is entering the cylinders (via a bad gasket) if the valves are burned or stuck open...........

Maybe the heads just need tweeking up. When installing new head gaskets the heads need to be correctly torqued. Then the engine should be run untill hot, cooled down and then re-torqued. Maybe they missed this last step. Cheers.

My garage was able to source a new laminated windshield for my gen1 sedan (not easy to find and very spendy ($400)) At the time they reused the origional gaskets but they suggested later that they could do it with a universal gasket.

I think you will find that the valve guides on the exhaust valves are a little longer than on the intake. Also they do not have grooves cut into them like the intake guides. In short I do not believe they are designed to take valve seals. Certainly I have never seen them on exhaust guides. Nor is there mention of it in any of the manuals. Never a bad thing to have a few spares. Cheers.

I managed to track down a EA71 manifold that was designed for the bigger Ea81 carb. I am busy port matching the manifold and modifying the carb. I have ditched the vac secondary and built a secondary linkage. Also shortened the accelerator pump linkage and have generally smoothed the carb intake My stock EA71 carb is 26/30, EA81 is 28/32, Weber is 32/36. I'm hoping that a port matched manifold and bigger carb will do work a treat. We shall see. But for now it would be interesting to know how people have gotten on with a 32/36 Weber on the EA71. How does it affect the power curve? What are the pro's and con's. Experienced feedback would be welcome. Cheers. Dirk

Maybe some pics would help us to help you.

How are you setting the timing?

Sounds like a timing issue. Maybe check vacumm lines.

Welcome to the forum. Cool name! Can I just ask you to clarify something? Have you managed to get it to run at all with the new distributor? If the engine has been rebuilt, it is possible that it does not have the origional flywheel on it. Therefore the timing marks could be wrong. Maybe pull N.o.1 plug out and establish TDC for sure. Is it points or electronic? Very rude question.... Did you remember to install the rotor? One more thing. it is also possible that you are 360 degrees out. Again you need to establish TDC on the N.o1 cylinder on its FIRING stroke. (valves shut)