WA240Z

50mm from the end of ram tubes to the face of the inside of the air box.

Reviving an old thread rather than starting a new one. I have just had my tacho converted to run off the negative side of the coil. While it was working with the electronic ignition upgrade it was out by about 300rpm between 2500-5000 and erratic above 5000rpm. With the conversion to the tacho completed it mirrored the dyno tacho exactly. Gauge Works in Albert Park Adelaide did the job, $160 and turn around was two days. Great service. Oh, and yes, undoing the wing nuts is a pain in the neck.

These quartz upgraded clocks from Gav are brilliant. I have had mine for about 9 months now, keeps perfect time.

Cheers guys. I was conscience of making sure I left as much volume after the rear carb as I could.

I think it is the cooler intake that has given the bump in HP, if I had thought about it at the time I should have taken the cold air piping off and given it another run with just the air box, would have been a good comparison. The high speed A/F ratio ended up being 12.4:1. Unfortunately I didn't get torque figures to compare during the runs, only the end result. Its the first time I have had a car on a dyno so I didn't know what to expect I just let the guy do his thing without getting in the way. The good news is though the air box isn't causing a big deficit. Just took the car for the second drive of the day, it is so enjoyable to drive, and that is the whole reason I have it. Billy

And the completed interior with luggage straps and harness/strut brace.

Also a couple of pics of the completed underside.

Hi Guys, The extra 4 RWHP was with the air box with 25mm ram tubes, air filter and cold air piping fitted compared to just the backing plate with the ram tubes. The A/F ratio was ever so slightly leaner with the air box fitted so the extra HP may have come from that. The two different scenarios below. Final result was 155 RWHP @ 6,500rpm and 185 Nm @ 4,950rpm. The torque curve was pretty well flat from 4,200 - 6,200rpm. On the road it has a nice steady idle @ 1,000rpm with a bit of torque down low for pottering around on the street, but it really comes alive at about the 3,500rpm mark and pulls smoothly all the way to the 6,500rpm ceiling I am setting for the engine. Also I have to be honest the car feels much quicker than the dyno results show, comparing to my 225kw- 440Nm daily driver, the 240z feels every bit as quick once up over 4,000 rpm. I guess at the end of the day the dyno is a great tool for tuning but the real proof in the pudding is on the track. Will see how my little engine goes against some of my mates with their Z's at upcoming sprints. The engine specs are: Original L24 with 0.5mm overbore to 83.5mm, standard stroke. Original con rods. Cast flatop pistons. E88 closed chamber head, 39cc with port, bowl and chamber work. 44mm inlet and 35mm exhaust valves. 10.2:1 compression Billy

Had the car on the dyno getting professionally tuned yesterday, ended up with the following: 34mm chokes Main Fuel - 140 Air - 200 Pilot - 57.5 Pump Nozzle - .45 Hope this helps, good luck. Billy

Finally was able to get a day off work and get the car onto a dyno and tuned properly. The car is very smooth with great torque and power, I'm very happy with the end result. The surprising thing was my cut and shut air box, with the air box on it made an extra 4hp, so happy with that also. Time to start really enjoying the car with the new setup and stop working on it.

Fantastic result. Gotta love what the little L24 is capable of.

Hi Rickers, Really enjoyed your introduction . My Z was always one of the great bonding topics between my father and myself, for over 20 years until he passed away 3 years ago. Working on the car these days still is the place I feel closest to him. I think it is a fantastic project you want to undertake with your Dad, good on you Rickers. I look forward to reading the adventures you and your Dad get up to with the car. Good luck on your hunt. Billy.

Congratulations on both entries. I wonder if this is the first time a 240Z has been displayed at Motorclassica? I have been meaning for the past few years to try and tie a work trip in to coincide with the show. Have managed to do it for both Phillip Island historic and the Datsun nationals at Phillip Island in the past but yet to attend Motorclassica.

So another quick update, I purchased a Les Collins overhauled 260Z gearbox with 2.9 first gear and short throw shift conversion two weeks ago. I pulled the old 3.3 first out and installed the new one yesterday. I now understand why everyone loves that gear ratio set so much. 1st-2nd and 2nd-3rd ratio spreading is so much better, and the short throw shift is really nice to use as well. After I had the gearbox in and tested I spent a bit of time this afternoon working on my mikunis to get better throttle response and A/F ratio readings. I leaned them out two steps down to 140 main fuels and also brought the airs down to 190 to level the A/F ratio out across the rev range a bit better. Its driving very nice, but its still quite flat between 3000 to 4000 rpm, it may be because of my short velocity tubes. So I think its time to get in on a dyno and tuned properly now. Will hopefully have another update in a couple of weeks. Billy.

Spent a bit of time tuning today, finished up with 190 airs and 140 main fuel. WOT under load is pretty close to around 12.5:1 A/F ratio and around 13.5:1 at cruise. That is probably as good as I will get it myself as a base line so its off to the dyno now. Will update once I have had it tuned properly. Billy.

Dam that 240ZG is nice, really nice. Reading a current classic car mag on the plane yesterday noticed a restored '74 260z Super Samuri conversion made 55,125 pound at auction in the UK.

Hi Scott, I have just recently fitted 44's to my L24. Based on my experience with my engine only I would agree with Luvemfast your carbs current choke and jetting is most likely closer suited to a larger engine capacity. I have 34mm chokes in mine which offers very smooth progression. My jetting is currently: Main Fuel - 150 Air - 200 Pilot - 57.5 Pump Nozzle - .45 Under load and WOT I am still too rich, so I have just been supplied 145 and 140 main fuels along with 190 and 180 main airs as my A/F ratio currently leans slightly the higher the RPM, while being too rich. As mentioned in my build thread I will have the car on the dyno in a few weeks to tune properly at the moment I am just working to get it close. I will let you know on the weekend how these new jets go and what combination I end up with. Below is a link to the Mikuni suggested base line jetting for various engines including an L24 with 44's, hope it is a help. http://www.mikunipower.com/PHHCarbs/PHHcatalog29.jpg Billy

Hi Justin, The Stewart Wilkins headers are well priced I think honestly for both the quality that you get and the knowledge that they have been designed, tested, modified and tested over the years to offer the best torque and performance. I also had mine ceramic coated. I am a away for work at the moment so will check the primary pipe sizes and lengths for you next weekend. Though I am sure someone else on here will be able to supply that info, or just give Stewart a call this week, he is very helpful. One thing to be mindful of using his headers, they will only fit with certain intake manifolds. I know I needed to file my Nissan Motorsport inlet manifold's cross brace sections so it all mounted up nicely. When I ordered mine he told me that there would be clearance issues with some inlet manifolds, best give him a call to discuss your setup. Billy.

Hi Justin, Sounds like a very nice build you are undertaking. Yes my head had a lot of work completed on the ports and bowls, sorry I don't have the port dimensions, the inlet ports are the same size as the gasket and the exhaust ports just under the size of the Stewart Wilkins exhaust header, this was to reduce reverberation (I think that's the word). The photo is a bit blury unfortunately but it shows some of the port work. The head head work, compression and ignition timing was all specifically done for the original Nissan Motorsports inlet manifold and Mikunis as that was my build plan all along. Gav, happy for the above photos to be included in the head section if they are useful for others. Unfortunately I don't have a photo of the ports before they were worked on.

D3c0y, I agree that the air box could well be hindering performance I will know better in a few weeks when I get a chance to have the car on a dyno. The modified airbox to suit the mikuni's was something I have wanted to do for sometime, more do with the finished product I wanted to achieve rather than outright HP. The money I spent on having professionals build my original L24 would have netted greater HP if I had invested the money in an L28 based build, but an L28 wasn't what I was going for. When I compete in some club competition, sprints etc. I will likely remove the airbox and fit longer full radius ram tubes. But for street driving the airbox should be fine, and it completes a look I wanted to achieve. Gav, the head is an E88 closed chamber, as you can see from the photo, But I have no idea what it originally came off I can only presume it was the EFI head. I am pretty sure it was 39cc chambers. The head is giving, with the eye browed pistons and slightly relieved block for the larger valves around 10.25:1 with 83.5mm bore and 73.7mm stroke. I did spend some time searching for it as all other E88 heads I had seen were open chamber. Before the engine was rebuilt it only had 69000 genuine miles on it and it was kept in good tune and serviced very regularly. But the torque with this new head, even before fitting the mikuni's is fantastic, I can only imagine just how good an L28 based build is if done properly. Billy.

Thanks guys, for those who asked here is a photo showing the back plate.

I have 25mm ram tubes on the carbs and use two K&N 240Z replacement filters, cut and glued together. Ideally I will source some better flowing full radius ram tubes, probably about 30-35mm in length. When I get the extra jets and get the car onto a dyno I will get a true indication how well this modified air box works or is a to restriction of performance. As far as sound, with the air box the induction sound is of course muffled to some degree, but at idle you get to hear that sweet high compression ping in the extractors. The mounting plate was very straight forward cut from 2mm sheet steel in a long oval to match the radius of the back of the original air box. Then just marked out the centers and chamber breather holes, used hole saw and file finish for the throats and drill and file for the breather holes. I cut one air box in half and used the centre section out of the second air box. This meant two joins rather than using 2/3 of each air box which would have meant only one join. This way it is symmetrical but a real pain in the neck for my poor fabricator at work to keep the whole thing square and true while welding the three cover sections together. He must of used 12 clamps to hold down on a true surface while welding. The pattern at the front lines up pretty good. And I used the original air box wing nut screws, just relocated. The clip, that was easy, its just a couple of suit case clips I bought from bunnings and then I bent coat hanger wire for the wire part that goes behind the back side of the air box. Then had them plated in the gold colour. Oh, and if your interested in the air box colour its powder coated, Coats Hire Orange.

Its a public holiday here in Perth today so thought I would take a couple of photos and update you all on what I have been doing with the old girl over the past 6-8 months. As the rest of the car has been shown the love over the past few years it was the engines time for a bit TLC. As my goal was to keep the car relatively factory original along with period modifications, basically a factory hotty, I have stayed with the car's original little L24. So out with the engine and over to Sydney it went to James and Brett at MIA. I also managed to hunt down an elusive E88 closed chamber, kidney shaped, cylinder head. The boys at MIA completed a full engine rebuild, bore 0.5mm, headwork, bigger valves, hot cam etc. James also supplied a period mallory twin point distributor and upgraded to electronic ignition. I purchased a set of Stuart Wilkins headers and had them ceramic coated. While this was all happening with the engine out it was the perfect time to restore the engine bay. So I stripped the engine bay of everything and sent the car to Fadelli Restorations again. Martin sand blasted the engine bay to make sure there wasn't any hidden gremlins, I was pretty confident there wouldn't be, and no rust or previous damage was found. So then he had his spray painter finish the engine bay off with a nice shade of lime,112, paint. Back to my place I re-fitted all the engine bay hardware, I had all the steel work re-plated, and installed the engine and gearbox. I ran the engine in using the old hitachi's, headers and exhaust. The engine had just so much torque, and life about it, I couldn't be happier with the result James and Brett have delivered. In the mean time, to top my hot little engine off, I sourced a complete set of Mikuni 44's along with an original Nissan Motorsports inlet manifold. These unfortunately took the best part of 6 months to get to me, but at least I have them now. So on these went along with a new 2.5" mandrel SS exhaust and heat shielding. And the result, absolutely bloody fantastic. I swear the 44's are like driving with fuel injection, and the sound of the whole package is wonderful. I have read for years some people saying that 44's and 2.5" exhaust are too large for a little L24, I think these comments must have all been made by people who haven't experienced a professionally built and prepared package. I fitted a wide band A/F ratio meter to help dial the carbs in before having the engine dyno tuned, its running a bit rich still even after a couple jet changes, so I have some more jets on their way and once here will get the car on the Dyno to be tuned properly. To complete my factory look I did a cut a shut on a couple of 240Z air boxes along with a cold air induction setup. I think its come up pretty good. I am really interested to see the difference in horse power between just ram tubes and my modified factory air box. So a couple of pics as it all sits now.

Hello, Great to have another WA owner, congrats on your purchase. I can recommend one guy, he replaced my chassis rails and restored my under body and engine bay. I have found his work always to a high standard and he is very approachable and honest. He has had experience with about 3 zeds now I think, does a lot of his own panel fabrication etc. Martin Fadelli from Fadelli Restorations,0429 086 522. He has recently relocated to Mandurah. Also there is a 240/260 register club in WA, we undertake several competition and social events per year, also monthly meetings. Would be great for you to come along. www.wazregister.com PM me if I can be of anymore help. Cheers, Billy.

Good God, now that is "different"