smokingwheels

A while ago I drove my Z into a dark carpark and did not see the island in the center of the driveway hence I ran my Z straight over the top of it and flattened the 2 chassie rails/subframe under the body down from the gear box down. I would like to fix it up, I had 1 idea to weld 3 strips of flat steel over the damaged area after tring to hammer it out. Do I need to take it to a panel beater and pay them to fix the rails to get it on the road again? Can post pic later if needed

The magic porting method is with wirewheels if you search Google Images for "smokingwheels" you will find a 2 pic's there. When I enlarged the ports in on my first engine 2002 I found that removing the grooves was too much hard work so I left them alone and used the head as is and discovered it was different. I have been testing the efficiency of my engine driving around the block eg city cycle anyway its gone from 21 to 37.45 mpg (us) I have posted my results on my forum, if you want the details I will post the link to it, however I think you can knock off a few mpg because I havent tested it to the standard. My fuel consumption record as I have reported everywhere is 60 mpg@80 km/h on a flat hwy in overdrive of a distance of 380 km on about 14L of fuel, witch is ~50 mpg (us) also there is about a 2.5L resolution on my fuel gauge and I can also get more fuel in the tank depending on the driveway slope at the service station. Anyway my engine wont get those figures again because someone put silicon into my engine oil and it damaged it, the thing is I now know it takes about 35 to 40 min to block your oilways and stuff your engine. There is also a few problems to sort out when I port an EFI engine. my engine has used about 1/3 of the normal fuel requirment for idle its currently running at about 1/2 the normal amount I have proof on youtube search smoking2wheels or I can post a link if needed. Question: on your carby if you unscrew the idle speed adjustment all the way will your engine stall? Reason: my carby is unscrewed completely and as slow as it will go and my engine will still idle at about 930 rpm when very hot.

Ignition control, well I can't find any around to do what I want so I put a request into the MSD engineers. If you might be interested to port an engine like mine you may need a good system to fire the spark correctly.

I have nothing to compare to, when air moves it create a pressure wave (sound), my manifold and head seem to oscillate when the valve's are shut I need to see if a smooth surface does this, this oscillation is a good thing because it keeps the air and fuel moving in. I have zoomed in at the waveform the first pic shows where the valve opens and the second one is better quality note: when the valve opens some times the signal goes a bit flatter Im not sure why this is as yet.

You use a wire wheel to port your manifold and ports, I welded an extension shaft to mine, your ports should look something like this have a look at my web site too there are intake recording on the sound page. http://ampair.tripod.com Beware there are pit really big falls with EFI systems. 1. WOT fuel delivery a 2000 cc engine needs 1000 cc/min with air cleaner removed. 2. Flap airflow meters would go off scale too. 3. there may be some spark timing problems to do with range. Beware the timing needs to be tuned as carbon builds up. I dont know why that is. I have a laptop interfaced to my second engine with my own program. eg computer controls the engine timing and 2 stage rev limit. The timing is linear with rpm as far as I can tell to 7200 rpm eg plot a line 0 deg at 400 and 35 deg at 10000, 6000 is about 20 deg from memory. If anybody has a flow bench handy you could bore out PVC pipe as a test, before cutting into any alloy head. Things like feed rate in and out of the tube would have to be noted I have a 1986 Nissan Bluebird wagon 2000 cc (no EFI on this one) I have tested fuel efficiency at idle and its in the range of 12 to 14.2 c.c./minute running a mixture of normal to slightly rich. I have the test video's on Youtube you can go to my web site to see the 5 clips there, http://ampair.tripod.com/Fuel.html From what I have read a normal 2000 cc engine at idle consumes 24 to 26 cc of fuel per minute. I have improve fuel efficiency under highway driving conditions, I have experienced as high as 60 mpg (4.71 L/100km) over a 220 km journey on a hot summer's day cruising around 80 km/h. I have a stock carby and my vac sec are fully open at 2000 rpm it used to be approx 4000 so I can only guess at the air flow.

It means I have a 2 stage rev limiter and a banger is a piston

yep I have experienced as high as 60 mpg (4.71 L/100km) over a 220 km journey with my latest engine

I have modified the intake track to be different than what is out there, I ignored what I read on the internet about porting and did my own thing. I was wondering if anybody was interested? I am also looking for sounds recorded from the carby when under WOT going thru the gears, you would need a laptop to record it, PM if you can do it for email address.

How All Started Some time in the year 2000 my neighbor gave me a cylinder head (AB7)? It was off a Nissan 4 cylinder L series engine. A friend of his gave me a 1983 bluebird wagon with a faulty carbie. I used the block out of this car for my 1983 Bluebird sedan. In my spare time I ported this head and a manifold that I had. In 2002 I installed the good block from the wagon and the cylinder head into my 1983 Bluebird. It fired up ok took it for a test drive wow it was really responsive. I had 33 cc in the chamber approx compression ratio 12.5:1 I found just by depressing accelerator to the floor I was able to create wheel slip in 2nd gear, going around a typical right-hand corner at normal speeds I was pleased. But the timing was really out when the revs where up past 3000. This engine had a very short life. * I ended up destroying this high compression engine, because of the timing characteristics that was needed to run it. * The strange characteristics. I found by revving this engine with no load above 3000 Revolutions Per Minute (RPM) it made a terrible knocking/banging sound like all the bearings were not there, but the block was in good condition before. The knocking/banging sound was constantly there when driving the RPM was over 3000 RPM. I had plenty of power under the hammer I was pleased with my work. The correct spark plugs for this engine would only last 3 days. I started replacing the all the high voltage components; the result was a slight improvement but short lived. I ended up reducing the compression ratio to 8:1 in 2002 I did know what else to do. I had discovered a way to run a spark ignited (SI) internal combustion (IC) engine several degrees After Top Dead Center (ATDC), all thought I did not realize at the time. * I connected timing light and started to investigate. I found the only way to silence the noise was to retard the timing back to 3 to 4 degrees Before Top Dead Center (BTDC) this was when the engine revs were over 3000 RPM, with no load on my engine. With the standard mechanical advance it then caused the timing at idle to be totally wrong. When at idle which is ~22 degrees less this engine would not idle, because it was being fired ~18 degrees After Top Dead Center (ATDC) which is extremely too late in the power cycle to achieve Peak Combustion Pressure (PCP). I now know from my 2nd engine the vacuum advance needs be approx in an 18 degrees range. * * I started to think. I could make a computerised ignition system I had a Laptop. I built up an interface for the printer port. I built the first interface with 2 transistors and 2 leds 6 resistors on a piece of veroboard soldered on the end of a DB 25 way connector . I bought 2 kits from altronics to try and tune the engine. 1 was the high-energy ignition kit and a programmable ignition controller that would allow a negative slope, however I found this was not good enough for my Engine. I then started to write a program in BASIC, the first one was just to delay the spark. It didn’t work very well but it did stop the knocking above 3000 RPM.I worked on the programs all night to try and overcome this timing problem. I quickly got a program to work and have been improving it till now (7 years). I had to grind out the locating keyway on a rotor button to allowing the timing signal to be advanced so the computer could takeover I had to manually enter the timing every 25 RPM into data statements. I gathered data over the next 8 months after lowering the compression to 8:1 in 2002. My engine died and I threw out but I should of kept the head. * * * Peak combustion pressure (PCP) needs to be achieved by the time the crankshaft is 17-19 degrees ATDC according to research I have done on the Internet. The second engine is now running with an advance is approximately 15 degrees BTDC at 3000 RPM with WOT. The timing drops with carbon build up thus is very unstable in the long term but if it keeps going we will end up firing after top dead center (ATDC) again. * I’ve found on many sites From Information stated that a knocking engine will quickly destroy the pistons and bearings etc Yet I was not able to melt my pistons even with 22-25 degrees to much advance. My engine was run with extremely heavy knocking AT WOT up to 6500 RPM through the gears to over 120 km/h on a hwy lots of times and never melted anything, But I was hammering the life out of the crankshaft and other parts below. * I would need to build a 3rd engine and do more tests. Assuming current data would be similar in range on previous engine at Wide Open Throttle (WOT) the original head may have been timed (fired) as late as 14 degrees ATDC above 3000 RPM and still achieve Peak Combustion Pressure (PCP), it’s a rough guess at best.But it’s a slippy slope estimating timing on the down side of the power stroke when no one has done it before. * * After suffering many personal hardships. I then moved to my sisters in Huntingdale and continued to improve my timing program. * In 2005 had the courage to start this project again. To work a head and manifold on another L series engine. * I got it all together in the 3rd quarter of 2005. Now with the second engine a mild version, the data that I have gathered it now indicates that there is approximately 30 degrees of vacuum advance, on a cold night. * I'm building a web site http://ampair.tripod.com

I have More Sounds on my web site now and timing graphs and a bit of blog http://ampair.tripod.com/Sounds.html I have recordings driving down the road as well. My site has videos as well very poor quality though cheers

oh well here goes... I wanted a High Compression engine. I had an extra .070" shaved off a good head. This lowered the top cog too far, a new timing chain was still loose when guides were at max. I looked at removing some links but was too short. I ended up moving the chain guide up and over quite a bit, had to add new steel and new holes, took one day to complete. I decided to scan the new guide for a future handy reference tool. see att Cheers

Crimp the fuel line and try again, could be dirty needle n seat Ive dropped the spacer on the float shaft, bugged if i could find it.. I stripped a small length of pvc cable and placed it on the shaft ran for years.

loud valve noise? check under the rocker arms for the insert/disk that sits on top of the valve stem, maybe.. The insert may have turned 90 degrees and put the valve out of adjusment. What were you doing when the noise started?

sounds like fun, destructive testing I like it.... I hope you look at the oil pressure at that speed too and have sum sort or cut out when all oil is flying around the crankcase in limbo.... ps my stock donk goes to 7500 before i kill every banger +-30 rpm but I only fire every second banger above 7300 +-30 rpm note im due for crank grind shortly note you need to move the chain guide to balance the chain path up.

Yes Ive got way too much time to play I measured the output of the fuel pump a few months ago Approx 1 L Min static So I will have to measure what the carbie holds Under test I ran out of fuel near the end of 2nd gear ~6000-6500 revs I reverse Engineered the fuel useage, around 95 hp /L engine displacment I dont know if its true, dyno places dont want to test a stock engine. They just laugh, and say Im waisting my money, well the 1/4 mile is cheaper for a few runs anyway and its more realistic. I read an artical in a mag about ways to inflate/deflate dyno results 1. placement of temp probe, for intake temp 2. use a fast acceleration ramp before mods to obtain lower hp readings 3. use a slow acceleration ramp after mods to improve hp readings from memory the errors were as high as 50 kw in a 300 kw engine. So beware of the settings some use to justify the results, I prefer to use the 1/4 mile way

Yes well, hmm Some of you said it wouldn't work, see old posts by SmokingWheels I still had to prove it for my self though. I'm not game enough to push my stock L series engine past 7500 at this speed the valve train just starts a light cardac arrest. This level of arrest was prevously 7100. However it will go ~100-200 higher, before things really stop working, I dont want any windows in my block again, Ive read that peak intake veloicty is good to about mark 0.5 Apply the Golf ball therory to the valve, So how heavy is the intake valve now at that speed? 1. lighter valve springs for same rpm 2. more rpm for the same springs and running gear 3. a little analog mod ????? well classified information....ATM Have I just removed excess/uneeded mass from the valve itself? PS in granny mode on the HWY 4.72 L/100 is my best in summer (59.1 MPG). "Anything above 45 MPG you need to tempture compensate the volume of fuel out of the pump" Cheers Greg

thanks Adam Im guessing, my system would approx double the voltage swing across the plug. Ive had a look at ION voltage plots which relate to combustion pressure and the cylinder pressure spikes all over the place just after ignition. I guess im looking to damp that effect down a little in order to run higher compression ratios. Basicaly there is 3 pressure pluses/phases 1. btdc at ignition, random spikes 2. at tdc flame front 3. atdc this is when the power is extracted hence 33% of usefull energy 66% waisted Greg

well in nature and the real world its impossible to heat a ball of air to 2000 degrees and charge it with 20kV then push it at someone. So shouldnt the spark thats triggers the burning of all that fuel be natural as well not like modern systems, eg a series of sine wave pluses across the plug, so rough figures -ve spark then + spark, at 8kh hz for 2-3 mS ? Would this be better and more natural? I seem to remember in the 70's that a good set of points would have slightly more topend power than a transistor setup, but the points would change farly quickly with time. >>>>>> so have 2 coils with digital control feeding into one point via a Y cable, one coil turns off for 1/2 cycle then the other turns off for a 1/2 cycle but the two coils would have to be connected oppsite though, and timed accuractly. I had started to play with this in 2003 the coil that I had starts at a frequency of 8 kHz and goes up to 16 kHz at resonance, I had a glitch and blew the output tranny in the early stages so thats as far as i got .. does anyone has the time and the inclnation to try such a thing? cause ive got enough to do most of the time.