Author Topic: 20/22r hybrid (Read 37063 times)

92yota · « **Reply #30 on:** Oct 02, 2005, 09:46:21 PM »

thanks

hawaii500_1999 · « **Reply #31 on:** Oct 10, 2005, 05:40:23 PM »

actually the 20r heads flow better than the 22r head because they are straight then they dive down to the valve.

the 22r head ports go straight, then over a speed bump, then down to the vavle.

yes the ports are larger on the 22r but it still doesn't make up for the geometry of the port. straight ports flow better.

you don't need to change the valves, you will still notice a huge power difference. but if you are going to now is the time.

one thing i never could tune out is the fact that i had to run 92 octane gas or it would ping. somtimes i could get away with medium gas but i had to listen to the motor on hills.

92yota · « **Reply #32 on:** Oct 10, 2005, 08:23:50 PM »

I have the same problem with the motor thats in my truck now its an 91 block with a shaved 20r head on it. I was hopeing that with a 82 block and a not shaved 20r head that i wont run into the same problem cause 92 octane is to expensive.

kyle_22r · « **Reply #33 on:** Oct 10, 2005, 09:11:32 PM »

yep, when you shave the 20R head and put it on the short deck block you significantly reduce the combustion chamber size, which really bumps the compression(i think over 10:1).

my '79/82 hybrid runs great on cheap gas, just need to get a carb that'll run a healthy amount of richness since my 22R carb ain't cutting it.

i think the 1mm oversized valves are a good improvement, $55 for a set from engnbldr.

before you do the swap, you should decide whether you want to keep your low end torque and fuel economy or go for horsepower and high revving fun. the 22R head's design allows it to produce more torque in stock form and gets better mileage because of the swirl ports. however as somebody said, the 20R has ports that dump directly into the cylinder so your fuel gets there in a hurry. it's all a trade-off whatever way you go, just like everything else.

hawaii500_1999 · « **Reply #34 on:** Oct 10, 2005, 09:45:02 PM »

Quote from: 92yota on Oct 10, 2005, 08:23:50 PM

I have the same problem with the motor thats in my truck now its an 91 block with a shaved 20r head on it. I was hopeing that with a 82 block and a not shaved 20r head that i wont run into the same problem cause 92 octane is to expensive.

wow!! a laser block with a decked head? i hope you are running an adjustable cam gear.

92yota · « **Reply #35 on:** Oct 10, 2005, 10:09:25 PM »

nope but iv always wanted to try putting one on cause it shure feels like somethings not right. So kyle if i put the 20r head on the 81 block the compression wont change any? I was hopeing it would come up a little bit. Now you got me thinking if i should just stay with the 22r head since it does have biger valves and i am after more low to mid range power.

79coyotefrg · « **Reply #36 on:** Oct 12, 2005, 09:28:39 AM »

Quote from: 92yota on Oct 10, 2005, 10:09:25 PM

nope but iv always wanted to try putting one on cause it shure feels like somethings not right. So kyle if i put the 20r head on the 81 block the compression wont change any? I was hopeing it would come up a little bit. Now you got me thinking if i should just stay with the 22r head since it does have biger valves and i am after more low to mid range power.

nope, 20R on 81-84 22 is a jump from 8.5 to 1 compression ratio to 9.5 compression, regular gas is fine for under 10.1 with the proper cam, the higher the compression ie over 10:1 you need more duration so as to overlap the valves at low rpm's
the compression on that 91 block and 20 head has got to be close to 12:1

get 89 octane and dump some octane booster in each tank, cheaper that way

oh and Kyle, my run to see the Mammoths was my first trip and the engines "break in run" and i got 19.5 miles per gallon

so the hybrid can get good mileage also

92yota · « **Reply #37 on:** Oct 12, 2005, 07:14:28 PM »

thank i think i will stick with the 20r head. I got the stage 2 cam from johns foriegn auto when i brought the rebuild kit is that cam any good?

bluetoy84 · « **Reply #38 on:** Oct 13, 2005, 03:52:33 PM »

Quote from: 79Coyotefrg on Oct 12, 2005, 09:28:39 AM

the compression on that 91 block and 20 head has got to be close to 12:1

Is this with the flat top pistons , or domes

I assume your talking about flat tops , because I would think you would have to cut valve reliefs if you use the domes.

I would have thought if you ran a 20r head on a laser block with flat tops the compresswion wouldn't be near that high . I know your decking a lot off the head , but it's still a dome head and the flat tops are designed for a closed chamber head which is a lot less CC's. Does anyone know how many CC's a decked 20R is compared to a closed chamber 22r.

Also I'm working on an adapter to put the 22re EFI intake on a 20r head. I'll let everyone know how it turns out. If it works I'll be building several if anyone's interested in buying one.

79coyotefrg · « **Reply #39 on:** Oct 14, 2005, 07:58:19 AM »

ok i was thinking with dome pistons, the timeing chain will need a link removed

yea my pistons are hypereatic 22R .060 dome pistons

bluetoy84 · « **Reply #40 on:** Oct 14, 2005, 08:52:13 AM »

So you are running an '85 + "laser" block with dome pistons and a decked 20r head. Didn't you have to cut valve reliefs in the pistons

Also if your using a laser block with a 20r head decked to the '85 up height wouldn't you just use the shorter timing chain for an '85 + 22r instead of trying to remove a link from the longer chain . It might work fine , but I would be afraid to take a link out of my timing chain.

Does anyone know what the compression ratio would be with a laser block , decked 20r head and flat top pistons ? Seems to me if you ran this setup with the dome pistons your comp ratio would be too high to run pump gas.

skid · « **Reply #41 on:** Oct 14, 2005, 09:10:36 AM »

Did a 84 block with 20 head a few years ago. 22r valves in the stock seats, bowl cut, ported and polished. Used the aluminum 22r rockers with the 20r springs. All 20r's I've seen came with heavy steel rockers. Valve float was 8000 with stock cam. Just had to see a couple time. It's helpful to find a 20r head that had a mechanical fuel pump too.

kyle_22r · « **Reply #42 on:** Oct 14, 2005, 06:53:48 PM »

Quote from: 79Coyotefrg on Oct 12, 2005, 09:28:39 AM

nope, 20R on 81-84 22 is a jump from 8.5 to 1 compression ratio to 9.5 compression, regular gas is fine for under 10.1 with the proper cam, the higher the compression ie over 10:1 you need more duration so as to overlap the valves at low rpm's
the compression on that 91 block and 20 head has got to be close to 12:1 get 89 octane and dump some octane booster in each tank, cheaper that way

oh and Kyle, my run to see the Mammoths was my first trip and the engines "break in run" and i got 19.5 miles per gallon so the hybrid can get good mileage also

nope! the early 22R has 9:1 compression, 20R has 8.4:1, lazer blocks got 9.5:1. don't quote me, but the 20R's combustion chamber size only has a single digit difference in CCs compared to a early 22R if i'm not mistaken.

79coyotefrg · « **Reply #43 on:** Oct 15, 2005, 09:13:36 AM »

um nope ive done the measurements myself on a 20R and a 22R head, the combustion was almost 10 cc's difference

mine is a 81 block and 80 20 head, with my cam i had to notch the pistons .180
i just held each one up to the head, marked with a marker where the valve would touch then notched, so as not to loose anymore material than i had to

laser block and 20 head would be like 12:1 this was what i meant in my first reply

Kyle the numbers on compression for adding the 20R head came from toysport and Marlin

with careful measurements on the bench my calculations of cr on my engine are 9.7 to 1

the only mod i did to the bowl of the combustion chamber was to smooth the edge of the head to prevent premature detonation

kneedownnate · « **Reply #44 on:** Oct 19, 2005, 07:21:29 PM »

the only mod i did to the bowl of the combustion chamber was to smooth the edge of the head to prevent premature detonation

Quote

go on........

79coyotefrg · « **Reply #45 on:** Oct 20, 2005, 07:26:21 AM »

Quote from: kneedownnate on Oct 19, 2005, 07:21:29 PM

go on........

um

where the edge of the 20 r headgasket would fit between the 20 head and 20 block, when using a 22 block and headgasket it leaves a kinda sharp edge around the bowl of the head, just smooth that edge a little with a dremel, or even a small file, to prevent that edge from glowing and causing detonation, helps to run the cheaper gas, you dont want to cut it down to fit the 22 gasket cause then you might as well use the 22 head

kneedownnate · « **Reply #46 on:** Sep 18, 2008, 04:23:33 PM »

Just thought I'd bump this since the question arises every now and then

RN37DD · « **Reply #47 on:** Sep 19, 2008, 10:04:36 AM »

shoot guess i should have done that too.. had some ping after putting a 20/22r together. tried playing with an adjustable timing gear.. didn't make a bunch of difference.. finally put in a fatter idle jet in in the weber and got rid of the ping. yeah it likes the $$gas better but i run regular. 18 mpg at 65mph. 4.56 dif 265x70 16's.. i average 16-17 mpg.. at 5500-6000rpm I'm sure it's only getting 10 mpg. my motor well diesel if i come in after a hard run and shut it off to soon. anyone ever try water injection?

kneedownnate · « **Reply #48 on:** Sep 19, 2008, 10:25:40 AM »

Te51levin did I believe, but that was on his wife's camry that would randomly shut off. Ultimately he had to pull the head and do some cleaning to fully squash the issue.

RN37DD · « **Reply #49 on:** Sep 19, 2008, 10:43:12 AM »

i guess i could pull the head off and take a look at it. that could be a detail that might make a difference. my truck dose run better on a cool day than a hot one. there's another sharp area on the 20r head between the valves, if i remember right. i know a IH scout that used to diesel at shut down and it stopped with water injection installed. might also work on a Toyota with high compression. kind of a lost art in these days of the o2 sensor.

kneedownnate · « **Reply #50 on:** Sep 19, 2008, 12:32:35 PM »

You know, had I thought to check this thread before I stuck the head on the engine going in my truck I might have done this, but it's not technically a hybrid anymore because I'm going to a big bore 20r (nearly a 22r now) block.

RN37DD · « **Reply #51 on:** Sep 19, 2008, 01:01:54 PM »

i just looked a an old 20r head off of a 20r engine. the outside edge looks like it was exposed to the combustion space even on a 20r bore. i think that might be a good area to clean up even on a bored out 20r block. spot 2 looks like it could get hot.. but might not be a factor.. intake valve runs cooler.

79coyotefrg · « **Reply #52 on:** Sep 19, 2008, 08:04:40 PM »

Quote from: 79coyotefrg on Oct 20, 2005, 07:26:21 AM

um where the edge of the 20 r headgasket would fit between the 20 head and 20 block, when using a 22 block and headgasket it leaves a kinda sharp edge around the bowl of the head, just smooth that edge a little with a dremel, or even a small file, to prevent that edge from glowing and causing detonation, helps to run the cheaper gas, you dont want to cut it down to fit the 22 gasket cause then you might as well use the 22 head

UM hmmm thats what i was saying above, the area "1" in your picture must be smoothed off or the "sharp" edge will cause pre ignition

newbe94 · « **Reply #53 on:** Jan 07, 2009, 01:07:01 AM »

ok i have a 22re motor an i was wondering if i should do the hybrid or should i just keep the re.

also does it have to be the 22r block an 20r head or could it the other way around

79coyotefrg · « **Reply #54 on:** Jan 07, 2009, 09:55:41 AM »

Quote from: newbe94 on Jan 07, 2009, 01:07:01 AM

ok i have a 22re motor an i was wondering if i should do the hybrid or should i just keep the re.

also does it have to be the 22r block an 20r head or could it the other way around

a 22RE cant be made into a 20/22 hybrid

using a 22head on a 20R block would cut your horsepower to maybe 70,

keep your 22RE, run a header and a LCEngineering cam

newbe94 · « **Reply #55 on:** Jan 07, 2009, 09:16:27 PM »

i know you cant use the 22re head. what i meant was should i pull it out an put in a hybrid.

i have a cam but not sure if it is good it an 271 pro comp an downy headers

kneedownnate · « **Reply #56 on:** Jan 07, 2009, 10:43:06 PM »

Keep your fuel injection and port the head. I don't think your cam will be big enough to mess with the efi too much. The header will be a nice upgrade, but don't expect a huge jump in power.

newbe94 · « **Reply #57 on:** Jan 07, 2009, 11:52:55 PM »

should i put a bigger cam

79coyotefrg · « **Reply #58 on:** Jan 08, 2009, 09:55:32 AM »

Quote from: newbe94 on Jan 07, 2009, 09:16:27 PM

i know you cant use the 22re head. what i meant was should i pull it out an put in a hybrid.

i have a cam but not sure if it is good it an 271 pro comp an downy headers

post the cam specs here and i can tell you

duration, lift, lobe separation, all that

TRACKER · « **Reply #59 on:** Jan 10, 2009, 01:51:32 PM »

about how much HP gain do you get from doing the hybrid vs stock 22r ?

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