4 Cylinder Block, Piston, Carb, Etc Specs
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Date: Tue, 13 May 97 09:29:24 -0600
From: bwiencek@kcnet.com
To: Jonathan Albrecht
Subject: RE: 1980 20R head on 1986 California 22R (long reply!)
>The attached file didn't come through so well on my end.. If you get the
>chance, to resend it, my setup just needs it to be 'attached' as a file.
>If you can do that..
Uh... OK...it was a UUcode attachment, but I'll attach it as plain text
to this one...
Here the big file attachment is... it's a compilation of posts from the
Toyota-mods mailing list...
____________________________________-
Blocks: (TopLine Part Numbers in Parens)
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(The 20R was first available in 1972 in the Pickup.)
75-80, 20R: (NA)
Bore: 88.5mm
Stroke: 89mm
Stock Piston: (NA)
Notes:
81-82.3, 22R/22REC: (SBTO80)
Bore: 92mm
Stroke: 89mm
Stock Piston: (PATO80)
Notes: Best Choice for Pistons (dome top). You can just deck
the block by 2mm and make this identical to the post-85
block.
82.4-84.7, 22R/22REC: (SBTO80L)
Bore: 92mm
Stroke: 89mm
Stock Piston: (PATO80)
Notes: Best Choice for Pistons (dome top).You can just deck
the block by 2mm and make this block identical to the
post-85 block.
84.8-95, 22R/RE/REC: (SBTO80LC)
Bore: 92mm
Stroke: 89mm
Stock Piston: (PATO80L)
Notes: Best Choice for Block. Piston is Flat-top. Block is
2mm shorter than previous 22R. This gives you a little
bit more compression, but you need an adjustable cam
gear to get cam timing right.
85-88, 22RTEC: (NA)
Bore: 92mm
Stroke: 89mm
Stock Piston: (PATO80T)
Notes: Piston is dished. (?)
Heads:
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75-78.7, 20R: (CHVTO8)
Intake Valve: 43mm x 8mm x 115.4mm (IVTO8)
Exhaust Valve: 36mm x 8mm x 113.9mm (EVTO8)
Notes: Best Choice for Head. Hemispherical combustion chamber.
Stock flows adequately for 6500 rpm.
78.8-80, 20R: (CHVTO8L)
Intake Valve: 43mm x 8mm x 115.4mm (IVTO8)
Exhaust Valve: 36mm x 8mm x 113.9mm (EVTO8)
Notes: Hemispherical combustion chamber. Mounts for power
steering and mechanical fuel pump. Stock flows
adequately for 6500 rpm.
81-82.3, 22R: (CHVTO80)
Intake Valve: 45mm x 8mm x 113.4mm (IVTO80)
Exhaust Valve: 37mm x 8mm x 112.4mm (EVTO80)
Notes: Swirl-type combustion chamber, poor intake ports. Not
enough flow for more than 5500 rpm.
82.4-84, 22R: (CHVTO80L)
Intake Valve: 45mm x 8mm x 113.4mm (IVTO80)
Exhaust Valve: 37mm x 8mm x 112.4mm (EVTO80)
Notes: Swirl-type combustion chamber
85-95, 22R/RE/REC: (CHVTO80LB)
Intake Valve: 45mm x 8mm x 113.4mm (IVTO80)
Exhaust Valve: 37mm x 8mm x 112.4mm (EVTO80)
Notes: Head is closed chamber. Domed piston won't work here.
If racing rules require flat top pistons, use this
head!
85-95, 22RTEC: (CHVTO80T)
Intake Valve: 45mm x 8mm x 114mm (IVTO80T)
Exhaust Valve: 37mm x 8mm x 113mm (EVTO80T)
Notes:
General Notes:
-20R and 22R Intake will not swap.
-20R and 22R Exhaust will swap.
-20R and 22R Cams are interchangeable. Cam design never
changed from the early 20R to the present.
-Note that the TRD "oversized" intake and exhaust valves
are only oversized if you're talking about a 20R! They
are 44mm/37mm--actually 1mm _smaller_ than the 22R valves!
-If the 20R can flow enough air for about 6500 rpm, this is
a 250 cfm theoretical maximum on a 20R block, 271 cfm
theoretical maximum on a 22R block.
Race Info:
- Post '85 22R block
- Pre '85 22R pistons
- '75 20R head
- '80-'84 22R intake valves
- '75-'80 timing chain guides
- post '85 timing chain
Dead Stock:
20R, 2190cc displacement, 8.4:1 compression, 96 hp
22R (Carb), 2367 cc disp, 9.0:1 compression, 100 hp
22R (EFI), 2367 cc disp, 9.4:1 compression, 116 hp
Wiseco Forged Pistons:
Dome Top Available in 89mm, 90mm, 92mm, and 92.5mm
-24.7cc Dome Volume, 38.94mm Comp. Height
Flat Top Available in 94mm
-34.90mm Comp. Height
All have identical wrist pins and circlips. Kits include
pistons, rings, wrist pins, and circlips. TRD's "10.5:1"
piston was the 92.5mm Wiseco (no indication whether it
was 10.5:1 with a 20R or a 22R head, but I'm betting it
was a 20R.)
Carb Info:
Carb Flow
Stock 20R Aisan 190 cfm
Stock 22R Aisan 326 cfm
Weber 32/36 325 cfm
Weber Dual 38 390 cfm (Downdraft)
Weber Dual 40 405 cfm (Downdraft)
Dual Mikuni 40 PHH 724 cfm (181 cfm per tube)
Dual Mikuni 44 PHH 844 cfm (211 cfm per tube)
CAP/American Cams (Regrinds):
(Cam lift listed; multiply by 1.44 to get valve lift.)
Grind Dur Lift AUC
O-65 280 .322 .250
O-77 306 .300 .255
O-78 316 .302 .265
O-91 280 .345 .268
O-71 300 .341 .284
O-92 290 .365 .294
O-94 304 .357 .301
D-23 300 .370 .308
D-350 320 .350 .311
O-68 330 .340 .311
O-93 296 .385 .317
O-74 330 .362 .332
D-29 306 .400 .340
D-420 306 .420 .357
D-22 320 .420 .373
---------------------------
Outer Valve Springs Beck-Arnley 023-0268 8 each $3.45 $27.60
$2.21 $17.68
Inner Valve Springs Iskendarian 626 1 set $36.00 $36.00
$19.80 $19.80
Header Doug Thorley 128-542Y-S 1 each $327.00 $327.00
$224.25 $224.25
10.5:1 pistons, w/rings Wiseco K509P925 1 set $439.67 $439.67
$362.82
$362.82
Reground Camshaft CAP/American Cam 1 each $100.00 $100.00
$70.00 $70.00
New Distributor/Recurvd Beck-Arnley/CAP 179-0229 1 each $51.00 $51.00
$31.33 $31.33
Master Rebuild Kit* Sealed Power MKP-854A 1 kit $375.00 $375.00
$321.83
$321.83
$2,706.19 $2,173.45
*Master Rebuild Kit Includes:
Main Bearings
Thrust Bearings
Rod Bearings
Gaskets
Freeze Plugs
Timing Chain Set
Oil Pump Set
Piston Rings
-----------------------------
Various info, including racing notes...
- Post '85 22R block
- Pre '85 22R pistons
- '75 20R head
- '80-'84 22R intake valves
- '75-'80 timing chain guides
- post '85 timing chain
- take a hundred thousandths off the head
- use 92 octane and up fuel
Adjust timing until it spark knocks and then back down until it stops.
With this combination you have to drill out the water jackets in the
center of intake side of head to use 22R carb. intake and it helps to
port the intake chamber to match the intake. The addition of 280. 441.
cam and header with 44mm or even better 48mm side drafts will make a mean
street and strip car. For pulling or autocross use the stock cam. For
autocross, 4:10 or 4:11 gears work well. For strip and street, 4:30
gears are nice. I have seen this combination make 2 1/2 to 3 1/2 seconds
difference in 1/8 mile strips. Something else that adds horsepower is to
cut the big ridge off the back of the flywheel."
You can cut down the cam stands and get more lift with stock cam. Cut
it down about .005", then go more as necessary.
For circle track applications, run a 280 degree duration, .441" lift
cam. Dual valve springs are better if you're going to run consistently
over 6000 rpm. Be sure not to run too much spring seat pressure--you
can break the tip of the valve off, dropping the valve into the cylinder.
Roughly 130 lbs seat pressure is a good figure. Avoid too much lift!
Most circle tracks require flat top pistons. In this case, you should
run the late model 22R head, not the early one, to take advantage of the
flat combustion chamber.
Use the old style timing chain kit (81-82.3) because they use the metal
guides rather than the later ones which use carbon fiber.
=========================================================================
Let me try to clarify just a bit. The 22R engine comes with flat top
pistons and the bottom of the head is flat also. The 20R engine has dome
shaped pistons and the 20R head is designed to accommodate the dome
shaped pistons. If you change just the head to a 20R on a post 85 22R
motor you will have flat pistons with a head designed for dome shaped
pistons. This leaves you with an engine with LESS compression than you
had before. To get the m