C.A.R. Posted March 5, 2017 Share Posted March 5, 2017 (edited) I thought this build deserves a thread of it's own, as the last 'Engine Build' thread I posted seem so popular. The whole back story as to how I ended up here is a long one deserving of it's own post, but for now I'll stick to the build dairy of my 'Early Girls' matching numbers L24. Some time in the late part of last century, Harry (the dear PO) had Gordon Dobie rebuild the L24, increasing it's capacity to 2.8 liters by using a L28 crank, rods & pistons. The E31 head had it's ports cleaned up in the short turns & L28 valves fitted. A mild camshaft was also added. Along with the 45mm ITB EFi it punched out around 150hp at the tyres on the dyno. This will take some time to progress, as I only started stripping the L24 down this weekend. I do however hope to have it completed by mid year (famous last words?). Why am I doing this you ask? Well some of those horses have escaped over the last couple of years & it had a propensity over overheat if I pushed it hard... The specs will be: L24 E31 block Standard P3040 L26/L28 Crankshaft 133mm H-Beam Con-Rods & ARP Bolts SPS 86.5mm Forged Pistons ATI Harmonic Balancer 2500lbs 200mm HD Clutch AZC Alum sump. E31 head - ported by Les Collins Camshaft - TBA Triple 44PHH Mikuni-Solex carburetors on a Kameari 'SmallPort' manifold w/ ITG JC100 filter. SWM 'SmallPort' Extractors (ceramic coated) 3" SS exhaust with FlowMaster mufflers. Expected power: 280hp & 220ft/lbs torque (approx) Here's the poor old L24 before I started stripping it down: I was concerned about the bore thickness since it had been overbored by 3mm already. Thankfully it was OK: Numbers are in thousands of an inch - e.g. '150' is 150thou or 3.81mm Accepted industry minimum bore wall thickness is 120thou or 3.048mm As a note, when I popped the pistons out, all the top rings were broken - not good, but thankfully no serious bore damage. However due to bore scuffing & general wear, it'll get bored 0.5mm as suitable cast pistons and/or rings are not available any more. Also cast pistons won't be happy for long over 250hp / 7000rpm+... Stay tuned for the next update Edited January 29, 2019 by Léon gav240z, locklock, hmd and 9 others 12 Quote Link to comment Share on other sites More sharing options...
Riceburner Posted March 5, 2017 Share Posted March 5, 2017 I'm tuned in mate, now hurry up and give us more updates! Quote Link to comment Share on other sites More sharing options...
russandra Posted March 5, 2017 Share Posted March 5, 2017 This build is going to be very interesting as I too will be doing a l28 rebuild within the next 12 monyhs or so. I intend to use a LD28 intake manifold with injector ports welded into the manifold for something diffrent. Quote Link to comment Share on other sites More sharing options...
Moderators PB260Z Posted March 5, 2017 Moderators Share Posted March 5, 2017 (edited) Hi Mate So the secret is out Looking forwad to seeing how this all comes together. I am expecting plenty of debate about the costs - should be fun. I do however hope to have it completed by mid year (famous last words?).See you at the Xmas BBQ. Cheers PB Edited March 5, 2017 by PB260Z C.A.R. 1 Quote Link to comment Share on other sites More sharing options...
road rider Posted March 5, 2017 Share Posted March 5, 2017 Gordon Dobie........now that's a blast from the past. Doubt many around here would be old enough to know who he was! Wouldn't have thought you would be old enough to remember him too Lurch He loved building engines with flat top pistons resulting in a healthy compression ratio. Will watch this thread with interest as well. Quote Link to comment Share on other sites More sharing options...
C.A.R. Posted March 5, 2017 Author Share Posted March 5, 2017 Gordon Dobie........now that's a blast from the past. Doubt many around here would be old enough to know who he was! Wouldn't have thought you would be old enough to remember him too Lurch He loved building engines with flat top pistons resulting in a healthy compression ratio. Will watch this thread with interest as well. Gordon is apart of my Zeds history - I suggest you have a read of my Early Girls build thread / history: http://www.viczcar.com/forum/index.php/topic,7104.0.html gav240z and road rider 2 Quote Link to comment Share on other sites More sharing options...
road rider Posted March 5, 2017 Share Posted March 5, 2017 You don't look a day over 25 Lurch! I will have a read of that thread, thanks. Quote Link to comment Share on other sites More sharing options...
mossy Posted March 5, 2017 Share Posted March 5, 2017 This already has me thinking of pulling out my l28 and putting my l24 back in. gav240z 1 Quote Link to comment Share on other sites More sharing options...
luvemfast Posted March 5, 2017 Share Posted March 5, 2017 Will be good to watch this build. Quote Link to comment Share on other sites More sharing options...
Administrators gav240z Posted March 6, 2017 Administrators Share Posted March 6, 2017 I'm watching this build with interest, since it's right up the alley of where I want to take my L24 build. Quote Link to comment Share on other sites More sharing options...
scott Posted March 6, 2017 Share Posted March 6, 2017 Loved the last build. Cant wait for this one Quote Link to comment Share on other sites More sharing options...
locklock Posted March 6, 2017 Share Posted March 6, 2017 Following! Quote Link to comment Share on other sites More sharing options...
Rickers Posted March 6, 2017 Share Posted March 6, 2017 It's going to be very interesting to follow, especially with prices disclosed. Quote Link to comment Share on other sites More sharing options...
andyk_79 Posted March 7, 2017 Share Posted March 7, 2017 Thanks for this Lurch. I'll join the list of followers! Quote Link to comment Share on other sites More sharing options...
Moderators PB260Z Posted March 7, 2017 Moderators Share Posted March 7, 2017 Hi Lurch With the pricing I assume you will be quoting, full retail off the street walkin prices for both parts and labour (including your own labour) ? Cheers PB Quote Link to comment Share on other sites More sharing options...
C.A.R. Posted March 7, 2017 Author Share Posted March 7, 2017 (edited) Hi Lurch With the pricing I assume you will be quoting, full retail off the street walkin prices for both parts and labour (including your own labour) ? Cheers PB Edited: After consideration, I've decided to keep the costings private. There are too many variables and in the end, the cost can becomes a negative talking point. Edited August 1, 2017 by Lurch ™ Quote Link to comment Share on other sites More sharing options...
Aaron Neubauer Posted March 12, 2017 Share Posted March 12, 2017 Subscribed! I too have been thinking about putting the matching number L24 after a long term build back into the 240z. Quote Link to comment Share on other sites More sharing options...
C.A.R. Posted March 14, 2017 Author Share Posted March 14, 2017 (edited) Not a lot of exciting stuff happening, it it IS progressing:I had to extract a broken bolt from the front of the block - an M6 timing case bolt had sheered off.Twas a bit tricky to remove! After block was totally stripped, I removed the OP relief valve & sleeve, then tapped the hole to 3/8 UNF: As I had an E31 head, it ran the camshaft spraybar. This is not an ideal setup as it can get easily blocked, & it is one of the reasons why Nissan changed to an internally oiled camshaft later in production. Rather than raid a later model head for it's towers, and as my towers were in good condition I simply welded the oil feed & mounting holes in the 3 towers up with my TIG: I also found out recently that new billet camshaft blanks ARE available (although not cheap!), so I've decided to order one of them & have it ground.This will keep the base circle large and help with rocker wear & geometry.Lastly, these arrived today: 133mm H-beams.I did a bit of eBay research & found a seller that was selling what 'looked' like MAXSpeed items, but for $100 less.I took the punt & ordered them: to my delight they were! They also look surprisingly similar to the more expensive Eagle brand items... Initial inspections reveal them to be quite good quality - Les measured the big ends, found them to be parallel & on bottom tolerance. I just have to check their weight and the little end sizes with the gudgon pins when the pistons turn up. The E31 head has been checked over by Les, to-whit he pronounced it fit for the scrap bin I objected. Les made a face. Then he conceded that Head Stud Developments could probably salvage it - for a price. TBC... Edited July 29, 2017 by Lurch ™ mossy, zed74 and Ponyo240z 3 Quote Link to comment Share on other sites More sharing options...
Administrators gav240z Posted March 14, 2017 Administrators Share Posted March 14, 2017 Nice work, I suspect most E31s are trash by now. As are so many of the earlier heads. Just another reason it's hard to find an original early car with early parts still on it. I'm guessing it was corrosion on your head also? Is there other mods required to fit an internally oiled camshaft? I seem to recall needing to block off another passage? Quote Link to comment Share on other sites More sharing options...
mossy Posted March 14, 2017 Share Posted March 14, 2017 Now I'm wondering if my E31 head might be knackered too. Quote Link to comment Share on other sites More sharing options...
C.A.R. Posted March 14, 2017 Author Share Posted March 14, 2017 (edited) I'm guessing it was corrosion on your head also? Is there other mods required to fit an internally oiled camshaft? I seem to recall needing to block off another passage? A small amount of corrosion, but nothing to be concerned about. The bigger issue is that it's likely become soft... I'm unaware of blocking off a oil feed passage...? Now I'm wondering if my E31 head might be knackered too. Mark, my L24 has had a fairly exciting life. I wouldn't stress about your E31 until it's been checked out Edited March 14, 2017 by Lurch ™ gav240z and mossy 2 Quote Link to comment Share on other sites More sharing options...
Administrators gav240z Posted March 14, 2017 Administrators Share Posted March 14, 2017 The bigger issue is that it's likely become soft... That's what she said, but it's ok they have drugs you can take to deal with that. Zing! CBR Jeff 1 Quote Link to comment Share on other sites More sharing options...
1600dave Posted March 14, 2017 Share Posted March 14, 2017 (edited) 133mm H-beams. I did a bit of eBay research & found a seller that was selling what 'looked' like MAXSpeed items, but for $100 less. I took the punt & ordered them: to my delight they were! They also look surprisingly similar to the more expensive Eagle brand items... Initial inspections reveal them to be quite good quality - Les measured the big ends, found them to be parallel & on bottom tolerance. I just have to check their weight and the little end sizes with the gudgon pins when the pistons turn up. I suspect a lot of these eBay "4340 H-Beam rods" come out of the same factory. I bought two sets of 6 generic 130mm rods from the same seller a while back, and made 3 sets of 4 out of them. All 12 weighed within a few tenths of a gram and checked out perfect everywhere else. Looking forward to the rest of your build ! Edited March 14, 2017 by 1600dave Quote Link to comment Share on other sites More sharing options...
C.A.R. Posted March 14, 2017 Author Share Posted March 14, 2017 That's what she said, but it's ok they have drugs you can take to deal with that. Zing! Simon? gav240z 1 Quote Link to comment Share on other sites More sharing options...
luvemfast Posted March 14, 2017 Share Posted March 14, 2017 Simon? Nope...... I'm over here *waves hand from corner, watching voyeuristic-ally gav240z and andyk_79 2 Quote Link to comment Share on other sites More sharing options...
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