troyjmueller

I've been working towards stage 1 on the 'ultimate fuel economy build' (maximum conventional fuel eficiency).

Towards that end, I've gone the NA route, high stockish compression (estimated 9.4:1 static CR) of the Early(1983) 22R Block / Late(1980) 20R Head. Head has been milled 0.015" prior to install, unknown previous machine work. Stock 20R Valves, 22R rocker assembly.

Costs:
Machine Shop Head Surface (your price may vary)
Head come from a core 20R engine that came with my
14' flat-bed' tandem axle truck, before I lengthened and customized it.
Head Gasket ~ $15.00
20R Intake Manifold Gasket (from swaping with a buddy)
Oil
Antifreeze.
Heater Hose.

I don't think I'm breaking the bank, so far.

Currently, Head is installed, Exhaust bolted to head, loose from tail-pipe.
Intake manifold Installed, pending examination of Heater Hose routing.

I have the Heater Hose (from the Heater Core) going to the BVSV on the center coolant port of the head (similar setup for 20R/22R). The coolant pipe from the timing cover is not yet connected to a hose; the 22R manifold had a connection underneath. 20R intake manifold does not have this connection.

20R Intake has a Hose Nipple on the top, near the EGR valve for the Choke. I am thinking that the easiest way to go is with a length of heater hose connecting the timing cover coolant pipe (passenger side) to the intake manifold top-side Hose Nipple, or in series with the water choke, if used.

The timing cover coolant pipes are different, too. the 20R pipe is longer, and curves near the end to bring the end of the pipe by the rear portion of the intake manifold. The 22R pipe is shorter, and ends underneath the front portion of the intake manifold.

The 22R Exhaust/Air pipe and the 20R timing cover coolant pipe both use one of the rear block bolts as anchor points, so you can't use both the 22R smog pipe and the 20R coolant pipe at the same time without modification.

last bit is some FYI for anyone wanting to do an Early Hybrid build-up.

troyjmueller

I've been driving a bit on my freshly-completed head swap. some specs:

Peak compression ~165#-170# on the high cylinders (about 15# higher than with the 22R Head). my altitude is 2725'.

Starting: A little harder to start (ignition is set @ 5 btdc according to underhood sticker, ignition timing is just a hair early. could be mixture related.

http://www.wallaceracing.com/dynamic-cr.php calculator indicates that this is in order with a 9.4:1 static compression ratio
(toyota stock 22R is 9.0:1; 20R is 8.4:1)
extrapolated cam intake close is between 30-35 ABDC, which gives toyota's advertised (manual) high compression pressure @ 172# at 0' altitude.

Bore: 3.622"
Stroke: 3.500"
Rod: 5.827"
Intake Valve Close: 30-35 ABDC
Boost: (Your Setup)
Altitude (Your Altitude)

Hope this helps.

Hernando

Hello. I'm new here. I drive a 2wd 1988 fed &Canada emissions package 22R. With the current setup I've been able to get 31.7 mpg commuting fwyspeeds of55-65 mph.

The truck is pretty barebones and features the granny gas sipper 3.07 final drive and 4 speed trans.

The motor seems like there is almost NO EFFORT cruising the city at 40mph on 4th and I feel this would most likely be the sweet spot for mpg. The only thing is there is no way I can sustain this speed without hitting a red light AND no way (especially here in SOCAL) that I can safely maintain that speed on the fwy.

I just googled into this post. Would like to see where this goes.

ThatGuy1295

I wouldnt worry about trying to get any better mpg then that. Especially by only traveling between snail and turtle pace. Just go as fast as your allowed everywhere then tell us your mpg. Cause thats what really counts as good mpg. Not just how good of mpg you can get under 40. If they made a car that got 40mpg at 25mph, and 5mpg at 50mph, then no one would want one of those right?

magentawave

So what is the latest with the 50 mpg Toyota pickup?