Speed_Office! Posted September 2, 2015 Report Share Posted September 2, 2015 what sort of compression would one get with an l20b block overbored 1mm using 280zx flat tops,fel pro gasket and an l16 head? anyone on here ever done it? Quote Link to comment
Doctor510 Posted September 2, 2015 Report Share Posted September 2, 2015 What is the casting # on the head? Quote Link to comment
67_1600 Posted September 2, 2015 Report Share Posted September 2, 2015 With an L16 head (38.5cc chamber), the calculator I use comes up with 11.277 with flat top pistons. With a peanut head (41cc) it shows 10.774 and with an open chamber head (45.2cc) it comes up with 10.032. In addition to the compression being too much for pump fuel, the L16 head (if really an L16 210 head) will really limit your power unless it's highly modified (bigger valves, port work, etc.). To use pump fuel, I'd go with an open chamber head like the U67 to keep the compression down. If you're just building a cruiser, I'd even consider going with the dished L28 pistons and a peanut head to get your compression down to just a little over 9:1. Quote Link to comment
datzenmike Posted September 2, 2015 Report Share Posted September 2, 2015 What is the casting # on the head? While any L4 head will fit an L16 they all came with 210 heads. About 38.5cc combustion chamber. L20B with 1mm over flat top pistons and 210 head I get about the same compression.... 11.38 This is a bit high for most users but the real 'problem' is the 210s very small ports and valves. It's been rumored that the 210 head was actually designed for the smaller L13 or L14 engine. I wouldn't run it on a much larger L20B. 1 Quote Link to comment
banzai510(hainz) Posted September 2, 2015 Report Share Posted September 2, 2015 L16(210 casting) Why bother unless it was a SSS L 16 head. ports are too small. 1.125 1 Quote Link to comment
Speed_Office! Posted September 2, 2015 Author Report Share Posted September 2, 2015 well im running 11-2-1 in my l28 right now on 91 pump gas, I don't see why it wouldn't work. the casting number is 210. I want to run it because its what I have available to me and it should have semi open chambers which from what i can tell also means semi closed chambers. seems like a middle ground between open and closed which should prove somewhat useful from a performance aspect. I was planning on porting it first as well. Quote Link to comment
banzai510(hainz) Posted September 2, 2015 Report Share Posted September 2, 2015 YOur in Lakewood? Theres got to be a L series head around. Unfortunaly you not taking our advice. The ports are small the valves are small. a 210 casting is only used for stock or just to get the motor running. Otherwise most poeple recycles these heads. I gave all mine away last year I run a a L20 head on a L16 and lay money it will make more power than the high comp stock head small port valve head. Quote Link to comment
Speed_Office! Posted September 2, 2015 Author Report Share Posted September 2, 2015 well actually I have relocated to Nampa,Idaho. I did find a rebuilt u67 head on craigslist for like 128,which sounds like a damned good deal to me. maybe I should try and pick it up? Quote Link to comment
67_1600 Posted September 2, 2015 Report Share Posted September 2, 2015 The U67 would be my choice for your piston choice - it's got bigger intake and exhaust valves plus larger ports and, at least for me, puts the compression at a more practical ratio. It really comes down to what you want to get out of it, but that 210 is definitely not a great starting point unless you are going to put a ton of work into it. If you want to go with a closed chamber, I'd start with an A87 or W53. Quote Link to comment
Speed_Office! Posted September 2, 2015 Author Report Share Posted September 2, 2015 anyone have either of these closed chamber heads for sale? Quote Link to comment
datsunaholic Posted September 2, 2015 Report Share Posted September 2, 2015 While any L4 head will fit an L16 they all came with 210 heads. About 38.5cc combustion chamber. They didn't all come with 210 heads. 1973 US-spec ones came with open chamber A87 heads (at least in 620s), and JDM ones from the late 70s came with either Closed-chamber A87 or W53 heads. And SSS ones came with 219 heads at one point. I've seen 4 different numbers-matching '73 620s and every one had an A87 head, including the one my Mom bought new in 1973. The 210 head is far more common, though. Quote Link to comment
Doctor510 Posted September 2, 2015 Report Share Posted September 2, 2015 I'll ask again, what is the casting # on the head you have? Quote Link to comment
Speed_Office! Posted September 2, 2015 Author Report Share Posted September 2, 2015 210, its okay though. i figured out what sort of head i should run. I got a w53 closed chamber lined up for $250! 1 Quote Link to comment
dat521gatherer Posted September 3, 2015 Report Share Posted September 3, 2015 Thats what I run is a w53 on a l16. 1 Quote Link to comment
mhub91 Posted September 3, 2015 Report Share Posted September 3, 2015 I've never seen a W53 head in person. Supposedly more "rare" than an A87. How about an N58 head, anyone? :thumbup: Quote Link to comment
datzenmike Posted September 3, 2015 Report Share Posted September 3, 2015 They didn't all come with 210 heads. 1973 US-spec ones came with open chamber A87 heads (at least in 620s), and JDM ones from the late 70s came with either Closed-chamber A87 or W53 heads. And SSS ones came with 219 heads at one point. I've seen 4 different numbers-matching '73 620s and every one had an A87 head, including the one my Mom bought new in 1973. The 210 head is far more common, though. An open chamber head on an L16 drops the compression to 6.72 7.72 or so.... ? There must be more to this. Quote Link to comment
mhub91 Posted September 3, 2015 Report Share Posted September 3, 2015 An open chamber head on an L16 drops the compression to 6.72 so.... ? There must be more to this. 27psi of boost???? lol! :poke: Quote Link to comment
datzenmike Posted September 3, 2015 Report Share Posted September 3, 2015 The trouble will that is it will only run right when under some boost. The rest of the time a pig. Quote Link to comment
shacks510 Posted September 3, 2015 Report Share Posted September 3, 2015 I had a U67 on a stock bottom end L16... it was a dog. I hated it. Made noise but went nowhere. Quote Link to comment
datsunaholic Posted September 3, 2015 Report Share Posted September 3, 2015 An open chamber head on an L16 drops the compression to 6.72 so.... ? There must be more to this. Maybe different pistons, but they're dished. I had the engine apart in 1992 when the head gasket blew (at only 75,000 miles, but the truck had sat for months at a time. My folks didn't use it much since a family of 6 doesn't fit). It had never been apart before. L16 block, A87 open chamber head, dished pistons, U20 casting cam. We had the head resurfaced when the gasket blew, and the compression was so high it pinged on anything less than 92 octane. But it always got horrid gas mileage. High teens. Quote Link to comment
banzai510(hainz) Posted September 3, 2015 Report Share Posted September 3, 2015 250 for a W53 is alot. Better be rebuilt already Ted(Tdajj) down in Nanaimo might have a head. Why Cause I gave him one Quote Link to comment
Speed_Office! Posted September 3, 2015 Author Report Share Posted September 3, 2015 its not, the seller just says thats its in good condition and is currently completely disassembled and ready to port. how much should the head go for then? Quote Link to comment
datzenmike Posted September 4, 2015 Report Share Posted September 4, 2015 210, its okay though. i figured out what sort of head i should run. I got a w53 closed chamber lined up for $250! its not, the seller just says thats its in good condition and is currently completely disassembled and ready to port. how much should the head go for then? A closed chamber head is better than a open chamber but a 210 is the best. Compression ratio on L16 210....... 8.5 closed... 8.21 open..... 7.72 Compression ratio on L20B 210....... 9.23 closed... 8.9 open..... 8.4 Quote Link to comment
67_1600 Posted September 4, 2015 Report Share Posted September 4, 2015 A closed chamber head is better than a open chamber but a 210 is the best. Compression ratio 210...... 8.5 closed... 8.21 open..... 7.72 All else being equal, of course. But without some serious work on that 210 head the W53 is probably a better choice for an L20B. As you said earlier, the 210 was really designed for a smaller displacement than even the L16. 1 Quote Link to comment
datzenmike Posted September 4, 2015 Report Share Posted September 4, 2015 Made some changes to my previous post. Quote Link to comment
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