ozconnection

Hallo there, I may have everything you need. Contact me and we can discuss your options. 0438243465 Mark.

"restrictor..........needed to slow the water down to make the temp more stable" Increase the pressure of the water around the head galleries is why a restrictor is used, nothing to do with the speed of the coolant. Think about it for a second or two. Water boils at @87 degrees in the alpine regions for example....it's to do with the ambient atmospheric pressure. How do we increase the boiling point? Put a restrictor in the cooling system and the pressure of the coolant will increase. Now we can boil it at @120 degrees. High school science stuff.

You're welcome Gareth. Why don't you try the restrictor first, without any thermostat. The resistrictor is designed to replace the thermostat in these conditions. Using both at the same time doesn't test either component to see which one is giving you the desired results you're seeking. The little taggy thing next to the main part of the thermostat acts as a tiny bypass. The thermostat cannot close off 100% of the flow with one of these thermostats. I have experimented with one and twisted it off and plugged the hole. I did this because I could feel hot water in the top radiator hose before the thermostat actually opened! Solved that problem. I don't know if your engine has the external bypass line from the thermostat to the intake on the front cover like mine does. I believe there is an internal one too for those situations that require it. They allow water to flow around the block before the thermostat opens, keeping the head of water pressure at a manageable pressure and prevent cavitation that would drastically reduce coolant flow through the engine. They did this for the people who rev their engine hard on a cold engine! Bad luck on track day man......next time hey! Cheers.

All water pumps will cavitate if you spin them fast enough, so the idea of reducing pump speed at 7000 rpm makes some sense. The thing is that at a point beyond optimum pump speed, block water pressure drops. Dropping the speed of the pump to a point to where the cavitation is eliminated will only RAISE the coolant pressure in the block water galleries! I believe that you may have had a 'faulty' welsh plug in your engine. Nothing more. Your pump, radiator cap et al are just upgrades on a standard setup, applying greater pressure on the cooling system to get more performance from it (pun intended BTW). You found your weakest link, more often its a hose and we wouldn't think too hard about that one, would we? You can check your block coolant pressure by fitting a pressure guage to a fitting below your thermostat. Don't let it go too far...35 psi is where you want it to peak and stabilize. Too much coolant pressure is dangerous. Restrictors are far more consistant to finding the right pressure than a thermostat. You have to deal with open/closed pressures, flow rates, block pressure and temps. For racing, restrictors are king. For a 'street' engine, go the thermostat route is my call. Cheers.

This topic has been a little quiet of late, thought I'd wake it up! I've very recently asked the question over on hybridz as to whether a girdle was really necessary for the L series. Tony D wrote that it wasn't. He said that back in the Electramotive days when they were running their awesome 700HP L28 turbo, they only upgraded the bottom end to ARP main studs. No girdle was ever used. The leaking oil was mentioned and Tony D suggested that it may be a PCV issue that was blowing oil out the rear seals. I'd like to know how much the standard PCV system can flow? Modifying the engine and revving it harder will naturally increase the volume of blowby gasses. With the crankcase becoming pressurized, oil is going to be 'squeezed' out at some point. Some engine builders claim more horsepower by using a vacuum pump on their crankcases, claiming that they get reduced windage. Oil will cling to a rotating crank due to negative pressure, so if the rest of the crankcase is negative pressure, then the preference is for the oil to drop to the sump rather than cling to the crank. Negative crankcase air pressure eliminates parasitic drag, oil leaks and cylinder wall overoiling so contamination detonation is reduced, allowing for more timing/compression etc for more power. Bearing wear noted. I've found that the tension created from the alternator/water pump belt will cause the crank to flex ever so slightly in the direction of the pull, causing a bearing wear to be found at the front and correspondingly at the back of the engine/crank main bearings. The crank is long and whip and flex is going to happen, electramotive just used ARP main studs....do we really need anything more down there?

You should really try and tell us where you want the torque increase to be. A V8 feels strong and throttle responsive because it has gobs of low rpm torque. A rotary in a HQ like the ones sold in Japan would have been awful to drive....no low rpm torque to speak of ie gutless. High rpm power is actually the product of torque multiplied by engine revs, and when you look at it like this, to make decent power, you'll require a head that breaths well at higher rpms. There is a limit to the amount of air a head can flow. The size of the port and the camshaft profile will determine this. So by using a big port and a big cam profile, you will improve torque but at ever higher rpms. The bigger ports and cams only work at higher rpms because it's only then that the airspeed through the ports is high enough to generate sufficient inertia to prevent the negative effects of reversion. At anything below these 'effective' rpms, the head isnt flowing fast enough, the big overlap is bleeding dynamic compression and torque will decrease. This isn't where you want to go if your looking for a 'tractor' or 'torquey' engine, one that generates good power (think the formula) at low rpms, say around 1800-2800rpms. On the highway in 5th, doing 100-110km/h, squeeze the throttle on a tractor engine. Now do the same with one of the 'other' engines and see what happens, or doesn't happen. If a low rpm torquey bastard is what you think you want, read on. It was suggested to use a turbo or supercharger for low rpm effect. It will work, for sure, but you'll have to drop compression and use a stockish cam. With a NA engine, keep the stockish cam and keep the ports stock and you'll be on the right track. Add some compression but don't go too high as the dynamic compression will cause the engine to detonate unless you modify your cooling system, use higher octane fuel, water injection, colder plugs and run mechanical advance without vacuum advance because it may overadvance momentarily. Advancing the ignition timing and cam timing will boost low rpm torque. 20 degrees static ignition timing with a dizzy with 14 to 16 degrees mech. adv. will work, all in by 3000rpm. Use a 6-2-1 header for better torque spread. A 6-1 header is usually 'tuned' for higher rpms. A 2.25 or 2.5 inch pipe will work just fine. Your intake setup will also have an effect on torque. My Arizona Z intake has been designed to boost low rpm torque and I wonder how many Aussies have tried this manifold for themselves. It works very well for me but required some unique tuning strategies to get it working properly. AFR's are also important for torque production as go too lean and the engine will ping, too rich and be slugish. The AFR's will determine ignition advance. A small Holley 4 barrel was used, small venturis and multiple barrels took care of both low rpm and high rpm scenarios. Just some stuff....... Did I lose power? Compared to what? A stocker? No, the thing has more power at max/peak power rpm's than before, but more significantly the torque curve has muscled up exactly where I want it to be. Responsive, economical, docile and reliable are important aspects for my streetcar. Just wait 'till you drive it. Cheers

150 maybe

How can we get one? Name, address, payment method(s) please?

Thinking a little further on the idea of colortune is what happens when you've got two of them? Put one in cylinder 2 and the other in cylinder 5 with a twin SU equipped engine. Check mixture balance between the two carbs. Unless you've got two oxygen sensors in the exhaust, can you check the mixtures like this any other way? Checking the plugs can give some insite but the results may not be so obvious. The carb airflow checker, Unisyn I think I remember it being called, will balance airflow between the carbs but does it do mixtures? On my Holley, set up as a dual plane with an Arizona 4 barrel manifold proved to me that the idle mixture curcuits were not sync'ed exactly the same. The idle mixture screws turned out one turn from seated didn't give the same response as each other at idle. (A manufacturing error perhaps?) Could two Colortune plugs (one in cylinder 2 and one in 5) give 'exact' carburettor syncronization? Faaark...maybe yes! Even if one mixture screw is turned out 1.1 times and the other 1.3 times but the colour of the burn is the same for both cylinders and banks, then it's tuned correctly, right? How else could you get and check this kind of sync.? Sorry to go off topic here but I think this is important enough to mention here. Cheers.

What Wayne G wrote worries me. Sniffing the exhaust isn't reliable enough. How can it be? Far from scientific. Leave it to the experienced 'old skoolers'. I read the Colortune information on ebay. It provides a range of colours for different conditions, even for idle!! Perhaps the best way to use it is on a dyno so that different loads can be applied and the mixtures easily seen. Having said that, oxygen sensors that are put into the rear tailpipe can measure the mixtures more effectively and some might argue "What's the point of the colortune then?" If you can't get to the dyno easily or regularly (cost), then there may be some merit in using colortune as a basic mixture set up tool. As far as the timing light situation goes, that's what I mean by spending your cash wisely. The Hella unit might be good but the one I have gives all the same features plus it has a tachometer built in and you can see what the advance is doing at different engine revs, all displayed at the same time on the LCD screen. I plotted both of my 280zx dizzy's for revs vs degrees and could see exactly what was going on. The hella is good, sure, but is it good enough? If you want to tune your engine, then this timing light is the one I suggest you at least consider buying. Once you have it, all your mates will want to borrow it...its that sik mate!!

I'm a little 'confused'. You said you were able to adjust the valve clearances to proper specs but weren't sure where to buy a timing light? I would think that removing the valve cover and 'knowing' how to properly set the valve clearances was a lot more technically difficult than setting ignition timing or where to buy a timing light....... :-\ Personally, I hate cheap timing lights. Do yourself a favour and spend some money on something decent. Snap on make a lovely professional grade timing light but they're way overpriced. Buying locally is expensive and with the strength of the Oz dollar, you should be looking at buying from O/S. Look on ebay. Even with the cost of postage, buying this way is cheaper. People may not like this, but I work hard for my cash and if I buy something that's the same and leaves a few bucks in my pocket what the hell.... Try looking for timing lights by Innova on ebay. I bought model 5568.......awesome.

Do you have an electronic ignition or is it just a standard points type? A poory adjusted points can cause your car to run rough....your colourtune proves what's happening in your chambers...intermittant non combustion of the air/fuel mix. Now that you have a 'tool' that can help you with the mixtures, turn your attention to getting the spark spot on. Start with new points and rotor and cap. You said they were a little 'average' Sort it. Process of elimination applies here. Optomise what you have. That doesn't cost too much if you don't have wads of cash ATM. I enjoy doing this. Consider it a challenge. Good luck...tell us how you get on.

Here is a picture of the water pumps. The left one is the standard L series, the right one is the LD28 version.

Yes, they might be oily, but get your mixtures right first. You will burn oil when your mixtures are very rich. The fuel saturated mixture that enters the cylinders washes off the oil that is there for lubrication and burns on the plugs. The oil itself gets contaminated with the extra fuel too, diluting the oil and makes it easier for it to get past the oil control rings. A easily fixed situation that can mimic a much worse engine condition (that you probably don't have). Replace your oil and filter ASAP. Sort the mixtures first. Good luck.

I think you missed the point of the original poster. :-\ I think I gave him an answer that he was looking for even if it wasn't the one you were. I made it quite clear that running the standard pump was acceptable for anyone and that running the LD was a viable option, just like the guy that runs an 80 amp alternator when his original 60 amp one will probably do. My usage is rooted into a discussion with Paul Ruschman aka Braap on Hybridz. It's a long story but I installed it with the intention of running a very advanced timing curve and experimented with increasing the overall cooling efficiency of my L28 to cope with the changes. It worked. Driving in traffic with a 1500kg behemoth, auto trans with a high stall, AC on with an AC condensor and trans cooler in front of my radiator plus a "bucket load" of low speed torque and ignition advance 'warranted' what I should have called "heavy duty water pump" rather than a "high performance water pump" but this may be just a case of semantics. You decide.