B^2 Posted August 20, 2021 Report Share Posted August 20, 2021 I came across a LZ24 with U60 L-Series closed chambered head that is for sale. Seller says it's been ported with bigger valves and cam but don't know what cam is in there yet. What kind of hp/torque numbers would be expected out of something like this? Right now I'm just running a L20B with dual mikuni 40's and wondering how much more different the LZ24 would feel. I know it's a bigger motor so it would have more torque but beyond that I'm not clear on what a setup like that puts down for power. Quote Link to comment
datzenmike Posted August 20, 2021 Report Share Posted August 20, 2021 From the Z24 short block for sale in the Classifieds.... "Well if an L20B makes 95 hp then scaling it up by 20% that's close to 115hp. With 9.5 compression and a Weber, probably 120. This is conservative. This won't be a rever like an L20B. With longer 96mm stroke the 'red line' is 6,250 RPMs but torque should be very impressive. You have lots of compression and with an 89mm bore and a Z24 HG you could unshroud the combustion chambers on a U67 or W58 head quite a bit for better breathing. 20% more air!!!! Then an old L16 4 into 2 cast iron header and a 2"+ exhaust system. I don't know 125? maybe 130??? Haven't even got to a cam yet." We didn't get closed chamber heads so this is an imported head. Similar to the U67 IIRC. There's nothing special about closed chamber heads only that they bump the compression. To really take advantage of the quench area on the closed chamber heard you need flattop pistons and the Z24 have 15cc dishes so a bump to 10 to 1 compression. Any chance you have the 510 4 into 2 cast iron manifold or headers? The L20B manifolds are not that great. Side drafts would be superior to any down draft carburetor. Bigger valves would also be a plus when trying to pull 20% more air through the head. Unknown cam? I would say at least 125-130 hp. Again conservative. Byron on The 510 Realm has a LZ22, cam and side drafts and makes 135 on the dyno. You should be better than that. I understand that the Z24 makes 130 torque at 2,800 but this is with the poor Z series head. The 240Z was 2.4 liters and dual SUs and it made about 150 HP. Six cylinder apple to your 4 cylinder orange but that's what 2.4 liters can do. Quote Link to comment
B^2 Posted August 20, 2021 Author Report Share Posted August 20, 2021 The seller said it has a regrinded u20 cam but that's about all they said about the cam. You can see the listing for the engine here. My thinking is with a setup like that I could almost bolt it right into my 510 and have roughly a 20% bump in HP with some more torque. Is it going to light the world on fire, no but it's a lot cheaper then swapping in a KA or building out my L20B. There is always the chance that the motor is fubar but at least it would be a $1,000 mistake vs something much more with a ka or SR. Quote Link to comment
datzenmike Posted August 20, 2021 Report Share Posted August 20, 2021 U20 is an identifier for L20B parts. The L20B crankshaft has U20 cast into it. Too bad you can't see it running first.... for $1,000. Has dip stick and the block vent tube i the Z series position. Quote Link to comment
banzai510(hainz) Posted August 20, 2021 Report Share Posted August 20, 2021 if this motor is all together and just needs to be bolted in then yes I would try it. if the cost isnt too much. Just bolt the 40mm carbs and there and go and see how it is also the closed chambered head is prefered as you dont have the detonation issues with a open chamber head when a L head is on a Z series block as I head of head gasket issues. be honest I would be happy with just the L20 . and just drive it. the 2400 is a low rpm motor and I remeber someone saying the oil pan should be modified cause of the longer stroke but IM not sure on this the the Z24 a fully counterweighted crank? Quote Link to comment
Icehouse Posted August 20, 2021 Report Share Posted August 20, 2021 2 hours ago, banzai510(hainz) said: if this motor is all together and just needs to be bolted in then yes I would try it. if the cost isnt too much. Just bolt the 40mm carbs and there and go and see how it is also the closed chambered head is prefered as you dont have the detonation issues with a open chamber head when a L head is on a Z series block as I head of head gasket issues. be honest I would be happy with just the L20 . and just drive it. the 2400 is a low rpm motor and I remeber someone saying the oil pan should be modified cause of the longer stroke but IM not sure on this the the Z24 a fully counterweighted crank? It's Tim's (Yellowcars) old engine. Not many miles on it. Quote Link to comment
banzai510(hainz) Posted August 20, 2021 Report Share Posted August 20, 2021 I remember Tim car didnt sound right It was like a off balanced Subaru motor. I guess he is still around? Tim that is> he putting in another motor in his car? I sold a extra Subaru LSD diff to him Quote Link to comment
Icehouse Posted August 20, 2021 Report Share Posted August 20, 2021 41 minutes ago, banzai510(hainz) said: I remember Tim car didnt sound right It was like a off balanced Subaru motor. I guess he is still around? Tim that is> he putting in another motor in his car? I sold a extra Subaru LSD diff to him Yeah he build another car that is super nice. I don't remember what exactly it sounded like. I just remember it being really tall engine. The hood had the "power bulge." like your pants. Quote Link to comment
banzai510(hainz) Posted August 20, 2021 Report Share Posted August 20, 2021 21 minutes ago, Icehouse said: "power bulge." like your pants. but on the rear side!!!!!!!!!!!!remember 1 Quote Link to comment
datzenmike Posted August 20, 2021 Report Share Posted August 20, 2021 7 hours ago, banzai510(hainz) said: if this motor is all together and just needs to be bolted in then yes I would try it. if the cost isnt too much. Just bolt the 40mm carbs and there and go and see how it is also the closed chambered head is prefered as you dont have the detonation issues with a open chamber head when a L head is on a Z series block as I head of head gasket issues. be honest I would be happy with just the L20 . and just drive it. the 2400 is a low rpm motor and I remeber someone saying the oil pan should be modified cause of the longer stroke but IM not sure on this the the Z24 a fully counterweighted crank? You will get some swirl/turbulence with a closed chamber but not as much as you would with flattops. The Z24 has huge 15cc dish so the air dosen't pinch as much between the piston top and the underside of the head. L20B has 86mm stroke while the Z24 is 96mm.... huge difference! Makes high torque from this and the 20% larger displacement. Stroke determines redline. L20B is 7K (who goes there? well you might with side drafts) Z24 is 6,250 RPM. The torque is strong with this one. You can safely run any oil pan on the Z24. Well I should say I put my L20B 710 oil pan on one and tons of room. I did make a windage tray/crank scraper though to keep oil splah off. Only the L20B and the Z20 (uses same crankshaft) are fully counter weighted. This ain't going to see anything over 6k. The Z24 is 2cm or 20mm or 3/4" taller than an L20B and 1.5 inches taller than an L16/18 Quote Link to comment
Icehouse Posted August 20, 2021 Report Share Posted August 20, 2021 2 hours ago, banzai510(hainz) said: but on the rear side!!!!!!!!!!!!remember BBAAAHHHHAHAHAHA Quote Link to comment
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