ktm

A blue one of these frequents Irvine's Cars and Coffee. Very nice looking car.

Actually, both myself and Jeff Priddy noticed that the car does run a little cooler. The lines at #5 and #6 promote flow from these eddy/dead spots, flow that was not previously occuring. Additionally, we noticed that the car came up to temperature more quickly and stabilized sooner.

Swing widely? I don't think swing is the correct word. Once the t-stat is open, then running a line to the upper housing would not be any different. Running it to the upper t-stat housing would be like running without a thermostat at all. It would take longer for the car to get up to operating temperature. Once the car is at operating temperature, the t-stat is open though not all the way (depending on the temperature rating of the thermostat).

Mine will trigger this behavior even upon a cold, first start-up.

I have Wolf setup to energize the fuel pump for 5 seconds. Most of the time it energizes the pump correctly, but sometimes it will only energize the pump for 2 seconds. Does anyone have any idea what may be causing this? I am fresh outta ideas.

My EMS controls my fan via a relay. The reason I ask is because a lot of literature states that running around 190 degrees is optimal for engine life and power. Grumpyvette has a great post in the SBC forum that discusses this issue for that setup. Those engines are ideally run at 190 degrees. Timz posted that his setup runs better at 190 degrees as well. I have been searching for a while trying to find the optimal temperature for our heads but to no avail. If running at 190 to 195 is fine and offers plenty of buffer, then I will adjust my tune (I start pulling timing and adding fuel over 195) and cooling setpoints accordingly.

Yes. The cam is always in contact with the rocker arms unlike the solid lifter heads that have lash adjustments. The hydraulic lifter heads do not need any adjustments and are very quiet.

I am ultra paranoid about doing heat related damage to my head (probably unreasonably paranoid) and have tried to keep the temps relatively low (below 190). My old set points on my fan were 181 on, 176 off. I now see after doing a fair amount of reading that this may be too low. However, most of the information I am able to find deals with modern aluminum heads and engines. This information states that many cars are setup to run at 190+; SBC setups over 200 before the fans kick on. For our L-series heads, what is everyones set points?

Nope, no mouse trap springs to speak of with a hydraulic P90a head.

I merely offered up the other bits of advice because your battery is low and I did not want to see you burning up other parts. You stated that with the car off, your voltage was 12.3. If you have a charger/tender, your voltage should be high 12s at least. If the lamp circuit is not exciting, then then voltage regulator could be the issue. Is it the stock 1975 280z regulator (externally regulated)? If not and you have an internally regulated alternator, then it is the alternator. Wizardblack suggested it a week ago. The circuit goes through an external voltage regulator located on the inner fender next to the alternator.

You alternator is not charging your battery. That is one of your big problems. You say the alt was bench tested, but by who, the place you bought it from? I had an Autozone reman fail on me within 1 month of purchase. You need to buy a battery charger and tender. Your battery is nearly drained. Charging a nearly drained battery can damage alternator. Running a fuel pump on such low voltage can damage the pump.

Techno toy tuning

Probably.....and it means that your battery is already dead. Anything lower than approximately 12.5 volts and your battery is drained. Fuel pump flow is related to the input voltage. Low input voltage results in lower flow.

I found this when searching for a good explanation of compressore surge. I am familiar with it as I run across it periodically in my line of work, but I could not quite visualize the impacts. This is a simplistic, yet practical, explanation of compressor surge that I thought I would share. We know that turbos flutter under surge, some can point to the surge line on a compressor map, but this gives a basic explanation about what is actually occuring in the engine system. Taken from www.passionford.com: Imagine the way our turbocharger's compressor is driven, right back to basics: The turbine wheel is spun by exhaust gas, utilising also the energy stored in the exhaust gas as latent heat. This force on the turbine shaft generates torque at the compressor end as they are physically connected. Remember that part as its the key element, Torque Ok, Now lets imagine our turbocharger compressing air, forcing it into the engine, the engine is utilising it.. what happens then? Ok, The engine expells it, and our turbine housing pressure goes up accordingly, the torque applied at the turbine wheel increases, increasing the spin speed and compressor efficiency at the other end. Great chain of events! End Result? boost is climbing nicely. Ok, Now imagine this scenario: The turbo begins to spin, as above, but the compressor wheel is generating more air than we can move and the torque required to spin that huge compressor is not being met? Remember that unless the air is processed by the engine, and expelled as hot, rapidly moving air into the turbine housing, our turbine shaft torque will not increase to spin the compressor faster, and it may well diminish.. our compressor is slowing, braked massively by the compressed air its trying to overcome and increase..... Result? Compressor starts to slow a little.. (beginings of a compressor stall) Ok, So now what? The engine is still rotating and consuming air, but the turbo has stopped producing an excess, so our engine has now had chance to consume what excess was available and the inlet pressure is now diminishing, the turbine torque is now increasing again... VERY IMPORTANT: Remember also that at same time, compressor resistance to spin has also dropped due to housing no longer being as pressurised and as a result, the torque required to spin it has dropped massively.. Boom.. Suddenly the Turbine wheels torque massively exceeds the compressors resistance and the turbo spins to speed in an instant!! Sounds great, rapid boost climb!! The compressors acceerating at over 2G BUT: We just hit the same problem again, our huge compressor has made so much boost, so fast, and is trying so hard to push the massive volume or air, that our YB cant use it.... so we start to slow again........ So we went: Fast, slow, fast, slow, or in other words: The turbo is Surging. As you can imagine, it continues this cycle until it hits the revs your engine consumes all the air.. then your away!! Please correct where there may be misinformation - TonyD I am looking at you. I searched around Hybridz for an explanation, but nothing came up regarding explaining the phenomenom.

Mr. Pot, say hello to Mr. Kettle.

Power is power; for a volume of air you need a certain amount of fuel (mass) to produce a given power. Stick with the calcs. By the way, don't knock the US rating of fuel injectors. Fuel requirements are MASS based, not VOLUME based. The cc/min is misleading.

http://www.atlanticz.ca/zclub/techtips/alternatorswap/index.html Look at the bottom of the page.

You are supposed to tighten them to 20 ft-lbs and then back the nut off 60 degrees per the FSM.

Same here but I angled mine so it would not have to do the double 90 degree bends.

Sean, you stated earlier that your feed line was ~4 ft long. I was using that statement to form the basis of my statement. My feed line is much shorter. It's hard to say what your true problem may have been. I am not saying you are wrong, I am just offering evidence that the problem may not truly be with the Walbro pump. You yourself said it worked fine for 14 months and 20k miles. Something changed.

My pump was pushing against a base fuel pressure of 53 psi, up to 75 psi under full boost, with no problems when I was running 42 lb injectors. As you said, results are all over the place. One issue could be the quality of the "Walbro". Apparently there are quite a few Walbro knock-offs floating around.

I would like to offer my own experience that is counter to Sean's. I have the same pump, but with a smaller run of hose from the pick-up to the pump inlet, feeding 72 lb/hr injectors. I do not have a single issue what so ever with the Walbro pump. The issue could be more about the sensitivity where a Walbro is located rather than implying that all Walbro's will have this issue.

Hilarious and shows a sense of humor!

Attworth, I had a tool in a Jeep SRT-8 do the whole bumper ride/accel and pull in front/brake check thing too. I aa driving my wifes Prius and have NO idea what set him off. After doing that insanity he pulls up along side my passenger side with his window down, mouth just a' flappin'. I nonchalantly looked over and blew him a kiss. He went apoplectic and kept trying to get me to acknowledge/respond to him. I basically neutered him and demonstrated that he was powerless in affecting me. Made my day.

Bartman, McFadden-Dale off of Maple will have a good selection, but I highly recommend their branch near Orange. The selection is much larger. They have everything you'll need.