I have two 22R one is a per Laser engine with dual timing chain and dome pistons, and the other is the later engine with flat top pistons. So my question is I am rebuilding one of them is there a combination of head and blocks from these engines that would give me better performance figures? Obviously a 20R head is the best choice on the early 22R block but 20R heads are hard to come by in Ontario Canada.any feedback is appreciated. Cheers, Steve
Just build a 22 r with a header cam and weber and you'll be happy don't swap parts id build the early one myself but that's personal preference that way if you found a 20r head you could build it then
Not at all .. Build you up a 22r .. If your going for a little more hp just for a daily cruiser. Put a small cam header carb .full exhaust . .. If the 20r parts are hard to get just stick with a full 22r setup you'll get nice results
But is there a particular combo or engine I should focus on? I have the understanding the flat top pistons are a little more efficient then the dome top
Very little efficiency differences between both pistons .. If your building the motor I would go aftermarket pistons raise the compression up into the 10.1 or slightly higher combined with previous mentioned mods .. Will net you a decently quick 22r ... .. These motors have low compression it's there dead spot raise it and combine it with a well flowing head and good cam you start to make gains that pay off
i only said use the older one cause you mention 20r head and that leaves it open as an option if you find one in the future
I also think you should build an early 22r with cam and header and whatever else you want, soo if you do ever find a 20r head it's an easy switch for more power.
The advantage that the 20r head offers is greatest for those who don't want to do a piston swap. Yes, they also flow a touch better, but (if I understand it right), are built for a different balance hp and torque vs the 22r (the difference is minimal anyway once you start modding everything else). If you're going to do piston swaps (heck, even if you're not), and intend on using an asynchronous carb (stock or the 32/36 weber), you can stick with the 22r, but look into the dual plane intake manifold and you'll get the same or better flow and air/fuel mixing that you do from the 20r intake. What this does is give each barrel it's own path almost the entire length of the intake manifold, so the air zips through faster and mixes the fuel/air better. Notably better low-rpm, no hit on high-rpm. If you have the later 22r (85+?), you can even get a bigger-valved head straight from engnbldr.com for a great price (sure, it's no stage 3 from LCE, but it's significantly cheaper for a daily driver). Add a cam of your choice (one of theirs or any other you prefer), and you've got a wicked setup. Also remember that the double-row chain setups (if you feel you want/need one) are available through LCE for the later years for something like $400. If you do lower-rpm driving a lot (3k and below), I would recommend on the exhaust a long 4-into-1 setup, because (again, as far as I understand) this is best for torque. Always remember to consider torque, because that's what these engines were designed around. A Tri-Y setup is supposed to be good all around (I don't have a clue). Honestly the stock exhaust is pretty damn good, but if you stuck with that, you'd want to combine the two pipes coming the cast manifold into something larger, 2-2.5", remembering that the larger you go, the slightly more torques you'll be losing in exchange for hp. It's all a balance, but the sweet spot has been said to be about 2.25" diameter before the cat (making sure your cat isn't a bottleneck). Good mufflers make a difference, too. Most of this info comes from things I've learned around dirt track racing and me cruising the interwebs. Many times a slightly more restrictive exhaust (to a point) can actually give you better performance than a completely open one. Keep in mind that I could be wrong on any of these points. Like I said, I learned it from other places. None of this is (yet) my real world experience.
Thank you all for the reply's my plans are to put oversize valves and a 270 cam from engine builder also am planning on a 38 Outlaw Weber for that little extra oomph. The later block I have already had the bottom end built when I bought it but want to put better pistons in it, but then when I got into the engine in my truck and realized it was an older version with dome pistons and a dual trimming chain I started wondering which I should do or mix up stuff to get the best possible combo.
Like said the main reason the 20r head is good is it has a smaller chamber than the early 22r head. It raises the comp to around 10:1 on stock domed pistons. It also has a better path from the intake to the value. The 22r has 1mm larger valves tho. I have that combo with a 4-1 header and modded weber 32/36. It rips around pretty well.
The dual chains came on 81/82. 83/84 had a single. Get a front cover from a 81/82 or a 20r to fit the dual chain. Those wont work on a laser block. I run dual chains in everything I build, Toyota or otherwise.
