Frankenstein Builds: Look here for project info

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Frankenstein Builds: Look here for project info

Postby PEZi » Wed Dec 30, 2009 7:31 pm

NOTE:the information in this thread has been borrowed from several other sources and no portion of it has been created by NICO.

Frankenstein motors:collect all the parts at pick-n-pull JY and buy it as a rebuildable $50 short block

Medium block 2.4 Liter.Stuff a Z24 crank and pistons into NAPS-Z or L20B block bored to 89mm by cutting down crank counterweights and clearance grinding block as per Ben Pila. This gives you a 2389cc L-series motor that doesnt require using defective (crack prone) Z24 block, fabricating timing cover, lengthening timing chain or modification to close hood. Z24 piston tops will need to be milled down slightly. Fedral-Mogul 33.8mm pin height pistons might not need milling? Click HERE for Bens write-up of necessary modifications.Compression ratio with Z24 pistons and open chambered head is 10.25:1 before pistons : modified Z22 block, modified Z24 crank, modified Z24 pistons, Z22S/ L20B rodss/2+r+p: 227.7piston deck height: 0.45 (above deck)

Stroker 2.3 LiterStuff a Z24 crank into a modified Z20/Z22/L20B block by cutting down counterweights as above.No piston modification or block boring needed for 2283cc L series.see for an exampleRuss noted that his deck height measured -1.77mm with the Z22E pistons that he first tried using, he eventually used milled Z22S pistons to achieve a higher compression ratio.Parts: Z24 crank, Z22E pistons, Z22S/ L20B rods in a Z22 block or +2mm bored Z20/L20B block.s/2+r+p= 96/2+145.9+32.1= 226.0 mmpiston deck height: -1.45mm below deck

Big Bore 2.3LKA24 pistons into a bored Z20/Z22/L20B block. The small 2.8cc dish area of the KA24 pistons helps to preserve compression ratio even with the low piston deck height. Compression ratio with a open chambered U67 head is 9.9:1 or use dished Z24 pistons and peanut chambered head for 8.9:1 compression ratio.Parts: Z22 crank, KA24 pistons, Z22S/ L20B rods in a +2mm bored Z22 block or +4mm Z20/L20B block.s/2+r+p= 92/2+145.9+34.0= 225.9 mmpiston deck height: -1.55mm below deck

Longrod 2.19L/2.24LStart with VG30E pistons and have the tops milled by 2.7mm to produce 29mm pin height. Custom pistons of similar specifications would also be recommended. Using the long Z20E connecting rods gives this engine a better rod/stroke ratio of 1.66:1. (stock Z22 rod/stroke ratio is 1.59:1). Start with +1mm VG30E pistons and bore the block +1mm to 88mm to gain a bit more displacement (2238cc). This engine with custom 89mm pistons is rumored to be the basis for the "rebello 2.3L".parts: Z22 crankshaft, Z22 block, Z20E rods, milled VG30E pistons.s/2+r+p: 227.5mmpiston deck height: +0.05mm (above block)

Long rod 2.1 Lparts: L20B or Z20 crank, Z22E pistons, Z20E rods in a Z22 block or +2mm bored L20B/Z20 block

This would be the best HIGH REVING, increased displacement, high compression, engine you could build from the mdium height L20B/Z20/Z22 size block. A "standard" L/Z 2.2 would have 5% more displacement and better midrange torque than this engine but the 2.1 longrod motor with 86mm fully counter weighted L20B/Z20 crank will suffer less vibraton at high RPM than the 1/2 counterbalanced Z22 crank and the hybrid 2.1L will have a slightly oversquare bore/stroke ratio, so better reving than the Z22 "truck engine".Rod to stroke ratio of the 2.1L motor is 1.77:1. Of all the possible L series motors only the L16 has a higher rod/stroke ratio (1.80:1). The long Z20E rods will reduce stress on pistons and help to make more HP at high RPM. The 1.5mm thick Z22E piston compression rings are thinner than 2.0mm L series piston rings so put less stress on the piston ring lands and are less prone to flutter at high RPM. In short, this motor should be a screamer if you build it well, balanced the rotating assembly, and use a suitable RPM cam, head and induction system.

The HOW TO MODIFY bible cautions against allowing the piston to come further than 0.30mm above the deck top, when built with 32.1mm pin height late Z22E pistons (1/82 and later), this motor when build would have the piston tops 0.05mm above. The "bad" honzowetz spec chart list Z22E pistons as having 32.5mm pin height so verify that you have the correct pistons.

With a high duration cam and high octane gas to reduce risk of detonation, you should be able to use a peanut chambered head to get higher CR and better chamber shape. The peanut head will be more detonation resistant for a given CR vs a open chambered head. If you are re-using old Z22E pistons, they will be 87mm. Engine displacement will be 2044cc.If you are buying new pistons, get Z22E pistons in +1mm oversize, 88mm and bore the L20B or Z20 block +3mm to 88mm or convert a Z22 block and bore only +1mm. Engine displacement with 88mm pistons will be 2092cc for a near true 2.1L motor. Did I mention that this motor make HP at high RPM!??

With 87mm bore, 86mm stroke producing 511cc of swept cylinder area, 9.32cc piston dish, 7.0cc gasket volume and the piston raised up above top of block by .05mm, using an open chambered head (U67 or A87) of 45.2cc volume, I calculate a CR of 9.31:1 or, if you used a 41cc peanut chambered head head, CR of 9.92:1. Check and verify the piston dish area and piston deck height!

Since planning this motor, I have realized that it should be possible to use VG30E pistons in this engine instead of the Z22E pistons. I am just not sure if the VG30E piston pins would be compatible with the L series connecting rods, I have seen conflicting specs for the VG30E piston pins that would/would not work depending on who is right. As far as I can tell, the earliest VG30E pistons used wristpins pressed into the rods while the later VG30E pistons use full floating rods retained by circlips.The pressed in pins should work on the L series rods (measure and verify!) of if you use full floating pistons, ensure adequate clearance between wristpin and conncerting rod hole and it will be necessary to drill oil supply holes in the connecting rod to splash lubricate the pin bore. The VG30E piston pin height is the same 31.75mm as Z20E pistons so the piston top would not protrude above the block thus no modifications to piston would be necessary. Compression ratio would be slightly higher with the VG30E pistons because they do not have the large piston dish of the Z22 pistons.

Long rod L18flattop Z20S pistons and peanut chamber head for 9.7:1 CR, better rod/stroke ratio for higher RPM.Parts: L18 crank, L18 block, L16 rods, Z20S pistonss/2+r+p: 207.66mmpiston deck height: -0.29 (below deck)

Low compression combinations for use with turbochargers

Turbo 2.2L7.87:1 Compression ratio with 45.2cc open chambered head.Parts: Z22 crank, 2.2E pistons, Z22S/L20B rods in Z22block or Z20/L20B block bored +2mm,s/2+r+p: 224.4piston deck height: -3.45 (below block)

Medium-Long Rod Turbo 2.05LUse 32.1mm piston, 149.5mm rod from late Z22E. These rods are not as sturdy as onther L series rods.Parts: L20B crank, Z2.2e pistons, Z22e rods, Z22 bock or Z20/L20B block bored +2mm overs/2+r+p: 224.1piston deck height: -2.85 (below block)

Short Rod L16This is my current low compression L16 for turbo use.7.8:1 CR using 37cc cylinder head. Lowering compression of a L16 would be easier by just installing a open chambered L20B head and using stock bottom end. I just wanted to utilize a good 37cc head I already L16 crank, L18 rods, L24 (flattop) pistons, L16 block.s/2+r+p: 205.2mmpiston deck height: -2.70mm (below deck)

Turbo L18Use deep dished L20B pistons in a otherwize stock L18 for 7.63:1 compression ratio (using open chambered head) or bore +1mm and use dished 280Z pistons for 7.85:1 compression ratio.

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Joined: Mon Nov 13, 2017 3:51 pm
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Re: Frankenstein Builds: Look here for project info

Postby ntn.wrng.w.nsnbtz » Mon Nov 13, 2017 4:43 pm

Hmmmm! Damn near 10 years and no-one commented ? ( :!] What d'ya think of this then ? A Z22 w. crank and rods std but drill and honed small end(gudgeons)for full floating KA24DE pins . Dished top pistons w. 2mm turned of the tops to get head clearance. Bored block of course to 89mm for the KA slugs. Oil gapped the mains to .003" from .0015" to compensate for pretty constant full power service. KA24e head which only came open chamber for 3 valves per cyl.+spark hole. Its going to be carbed on a fabricated intake made of the KA-e flange and part of tubes, and the Z22 carb plenum welded together. I will probably use the van type sump with the wide winged and slightly windage trayed bottom section. I found the KA24e head bolts are 5mm shorter than the Std. Z22 bolts yet the head is 2mm thicker. I'll use Z22 bolts.
Now for the shocker ! It's going in a 2wd D21 crew cab Navara for towing duties and general inter city fetch and haul . And 5 Speed w. 4.625:1 H233b rear.
Thats my ten cents worth on a ten year old thread. One of the things that I trust is highlighted is that todays hot topic in a thread will be read in the future. it could be 100 years from today ? But there is no use by date on websites or google search links. What was written ten years ago will be somewhere for others to see even in the distant future if a spark of interest leads here or where the reader finds our words.
Finally if I'd realised the costs of this franken engine would balloon as has happened Ld just have financed a perkins deisel and six speed auto or SR20Det rwd front cut and merged the vehicle/engine deal in a fortnight :spitout: . The one good point is no-one will notice any changes so it won't need to be DOT certified. That & its still basically Nissan built and the swap will be finished in three or four hours while I've still used the vehicle all the while! :dblthumb:

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