Topic: Thinking about getting bigger cam??

[Gnarly4X]

Torque at as many rpms as possible. I think you have the data already. Basically, the data to plot a nice torque curve.

Hi blackdiamond,

My Engine Analyzer software will plot graphs for you, however the range of RPM is limited in this version to 10 increments.  I can send you one so you can see.

If you want to plot a line graph is Excel, you can use the sheet with the 100>5000 torque numbers.  You should be able to plot a graph with that data.  I haven't played with Excel and graphing this data.

Gnarls.

[Mudder]

Y'all haven't mentioned it is possible to over gear for the tires you are running. By the way Gnarly, I'm happy to see you back. I remember reading the numbers you supplied for cams over on Pirate when looking for the best cam for me.

[79coyotefrg]

I think putting it up with a 325 cfm carb and a header would be a typical 20r.  The reason I'm interested in this is that my 20r has clearly different and more eager driving characteristics than my 22r. That head is really doing something despite the smaller 2.2 displacement, even bone stock.

I know it's probably not possible to account for the better flow of the head but it would be fun to see what the smaller cubes and square bore/stroke relationship do to the numbers.

the 20R head and intake are greatly superior to the 22r as far as flow.  BUT the stock round 20r carb is a 190 cfm carb,  lce makes an adapter to put a 22R carb on the 20r intake.  I got the weber years ago and that made a significant improvement.
I ran a 20r head on my 22R block for a couple years before I blew it    but I will build another one.

[Gnarly4X]

the 20R head and intake are greatly superior to the 22r as far as flow.  ...

engbldr sells new 22 heads, I assume new 20R heads are available?

Gnarls.

[blackdiamond]

Hi blackdiamond,

My Engine Analyzer software will plot graphs for you, however the range of RPM is limited in this version to 10 increments.  I can send you one so you can see.

If you want to plot a line graph is Excel, you can use the sheet with the 100>5000 torque numbers.  You should be able to plot a graph with that data.  I haven't played with Excel and graphing this data.

Gnarls.

I started a new job this week and so far it has gotten my up earlier and kept me busy and I am still working to recover the house from last weekends camping trip so the end result me not having time or energy to mess with this yet. I would like to eventually.

[Gnarly4X]

Y'all haven't mentioned it is possible to over gear for the tires you are running. By the way Gnarly, I'm happy to see you back. I remember reading the numbers you supplied for cams over on Pirate when looking for the best cam for me.

Hey Mudder,

Thanks, yeah.. those were interesting days over on the P-site. I got sick of the "F-ing you" retards and the a-hole moderators.

Yeah... sure you can over gear.  You will end up running out RPMs on the top end but have some awesome tree-stump pulling torque on the bottom end!!

Looking at my gear ratio sheet, you can see that the best R&P choice will give maximize use of your peak torque. The numbers show that you get peak torque numbers 4 times within your RPM range = more power to the tires more often.

Gnarls.

[Gnarly4X]

I started a new job this week and so far it has gotten my up earlier and kept me busy and I am still working to recover the house from last weekends camping trip so the end result me not having time or energy to mess with this yet. I would like to eventually.

Hey blackdiamond,

Yeah.. I'm real familiar with time, work, house, no-energy, and chores.  My little boy "Teddy Bear" wakes me up every morning about 3am. I don't get home from work until about 7:15pm.  By 8:30pm I'm passed bushwacked, nearly brain-dead and moving at a Marlin dual-case 1st gear crawl speed.

If you want to see torque/HP charts, I'll see what I can do with Excel's graphing feature after I work on the 20R data.  I'm not an Excel expert, but I like to learn.

Good luck with your new yob@!!

Gnarls.

[H8PVMNT]

Wow... that's interesting.  It's less CCs?? The head is supposed to be better than the 22s?

Gnarls.

Yes, that is why people use the 20r head on an early 22r block to make a hot dog, 20r/22r hybrid 4 banger.  My machinist measured them side by side and the 20r head has smaller ports, but they are round and have a better shape for flow.  He said this design typically makes more torque because it keeps things moving faster.  The 22r is more of a swirly, tumbley flow for emissions.

I can tell you I have both engines in trucks right now and the 20r even with the stock bottom end just feels a bit more peppy and definitely has more pull up hills.  It also wants to rev higher and doesn't have that tight feel over 4,200 that a stock 22r does.

Now we are talking early carb stuff, mind you, with the different block.

[blackdiamond]

Hey blackdiamond,

Yeah.. I'm real familiar with time, work, house, no-energy, and chores.  My little boy "Teddy Bear" wakes me up every morning about 3am. I don't get home from work until about 7:15pm.  By 8:30pm I'm passed bushwacked, nearly brain-dead and moving at a Marlin dual-case 1st gear crawl speed.

If you want to see torque/HP charts, I'll see what I can do with Excel's graphing feature after I work on the 20R data.  I'm not an Excel expert, but I like to learn.

Good luck with your new yob@!!

Gnarls.

I would just need a table with rpm and torque to get me started.

[Gnarly4X]

I would just need a table with rpm and torque to get me started.

Can you download the Updated Excel sheet I attached yesterday or a couple days ago? It's the cam comparison sheet.  If not I can email it to you.

Gnarls.

[Gnarly4X]

I am convinced the 20r is better than the 22r as far as drivability goes.  Much more rev happy and feels like a better torque curve all around.  I'm sure it's the head design.

I looked in my dyno library, I found some 20R engines I tested back in 2001.  I will verify data and specs, do some pulls, and try to post something tomorrow.  I have some pulls with a 20R stock, a 20R with Weber, and some cam changes.

Then we can put a 20R head on a 22R block and pull it's torky little butt about 5 times and see what pops out!

Gnarls. 

[Gnarly4X]

Hi H8PVMNT,

I've attached an Excel sheet for download and review.

The numbers are from the best specs and data I can find so far.

I compared the 20R stock engine and then simply added a Doug Thorley header, 2" exhaust, with a free flow muffler.  The numbers support the commonly projected increase in torque and HP of about 10%.

What I find really interesting, however, is your butt dyno analysis, which is very accurate, and is supported by the numbers. 

Your earlier comment....  "I am convinced the 20r is better than the 22r as far as drivability goes.  Much more rev happy and feels like a better torque curve all around.  I'm sure it's the head design."

I think Ted and Tod at engbldr would agree with this...  You can test an engine on a SuperFlow 902 engine dyno, see lots of granular output data. Then install that engine in a NASCAR Sprint Car and the driver will have "feedback" from his butt dyno that the $50,000 902 could not analyze!

The torque numbers show the flattest curve I've seen - 3,000 to 3,800 RPMs!!!!

I am working on adding cam profiles and Weber carb.  Then I will put a 20R head on a 22.  I'll post those results later.

Any comments?

Gnarls.

[H8PVMNT]

That's really fun, thanks!  That's what it feels like too.  It "ramps up" torque faster than my 22r and pulls harder, longer. 
Must be the "square" bore and stroke design.  I can't wait to see the numbers when you throw some cams at it.

[Gnarly4X]

That's really fun, thanks!  That's what it feels like too.  It "ramps up" torque faster than my 22r and pulls harder, longer. 
Must be the "square" bore and stroke design.  I can't wait to see the numbers when you throw some cams at it.

Hey H8PVMNT,

If you are interested, here's a glimpse of some of what has taken me 100's of hours of reading, research, self-educating to better understand these little engines..... I'm still a very long ways from an engine builder, but learning new "stuff" every day.

I was playing with the 20R last night.  I ran into a different issue while looking at the results when changing from the stock cam to several of the cams I've tried in the past for the 22s.  I also changed to a larger cfm intake and exhaust. 

What's was initially puzzling to me is the torque numbers drop?  Since the internal combustion engine is really a big air pump, typically, when we improve flow (bigger cam, larger exhaust, more fuel and intake cfm) we improve the numbers - torque and HP.

Because this software is very sophisticated I've had to spend more time in the analyze and reporting feature to see what is causing the drop.

Here's and example of one section out of multiple pages of the Analysis Report on a stock 20R engine with 261C cam, DT header, 2" exhaust with free-flow muffler, Weber 32/36 carb:

"Maximum Exhaust System Backpressure 'Exh Pres' is  .5 PSI.
This is low for a street vehicle with a full exhaust
system.  This is simulating either an extremely free flowing exhaust
system or open headers or open exhaust manifolds.  This may be
illegally loud for street operation."

"Minimum A/F Mixture Quality 'A/F Mxtr Qlty' is  63.3 %.
This is Very low and represents a real power loss in your
desired operating range.  This can be improved by reducing intake
runner sizes, carb size, going to fuel injection, heating the intake,
increasing compression ratio, going to a lower octane fuel (the
program assumes high octane fuel has lower Reid Vapor Pressure and
therefore does not atomize or mix as well), smaller plenum, etc."

"The Inertia tuning of this intake is tuned to 5475 RPM,
which is close to your 'Desired HP Peak RPM' of 5000 RPM.
Since this RPM is about where the HP peak should occur, peak HP
should be good.  If you specify longer and/or smaller diameter intake
runners, you will likely gain Peak Torque and lose some Peak HP."

Although this program may not produce the exact numbers for a given set of factory engine specs, it is very accurate at analyzing and then reporting on "changes" from a baseline.  In other words, if Toyota's factory publishes the brake torque and HP for my 1986 22RE at 116 HP at 4800 RPM, and 140 lbs of torque at 2800, the program may not necessarily indicate the same numbers.  Why?  Well, how do we know under what conditions Toyota tested that engine? But, if change the intake and exhaust valves from factory stock to engbldr's over-sized valve option in the RV head, the program will accurately analyze that change... laws of physics and history data.

I'l do some more research.  It may be that a stock 20R, as designed by the Japanese auto engineers, is limited to modifications to improve power by the smaller valves and flow?? 

So..... this leads me to understand why, as reported by guys, that the 20R head on a 22R block improves the performance over a 22R head on a 22R block??  I'm probably just missing something real obvious.

Gnarls.

[H8PVMNT]

I would concur about the backpressure in real life.  Right now my header is broken at the first y pipes and it's shooting flame right out the 2 holes.  It felt fine with good exhaust but it really opened up high rpm with the busted header.  Floor boards get pretty hot though .  My 22r on the other hand seems to thrive on backpressure.  I actually picked up mileage and it pulls passes a little better with a stock muffler and 1 3/4" tube than it did with a flowmaster 44 and 2 1/4".  Weird. 

Also, my 20r loves to run on junky 85.5 octane, whereas the 22r needs at least 87.  The carb is small on the 20r, but the jets are HUGE compared to the 22r carb and it clearly runs richer in stock form.

The way it was explained to me regarding the smaller ports and valves, is that while it's moving less volume at once, what it is moving is moving faster, kind of like when you spray water out of a plain garden hose or when you put a restrictive end on it.  This effect according to my machinist will create more usable torque.  This is a second generation race car guy who has done a bunch of fancy port work and got to see the results in real time.

Obviously more flow is more flow and the practical application of this depends on a great many other things like the shape of the ports and all that but I can verify his theory in real life comparing my 22r against the 20r.  The 22r maybe has more, but the 20r does it with more pizazz.

The popular 20r/22r hybrid must be basically taking what the 22r has and making it act like the 20r.

[Gnarly4X]

Hey H8PVMNT,

Just to add to the discussion, I'm probably not saying anything you and many other here don't already know.

Not too unlike the mysteries of camshaft profiles, backpressure is another dynamic that gets thrown around in general conversation - usually about headers and exhaust. Actually "backpressure" will negate the exhaust flow and the power of an engine. What we want in the exhaust function is flow, but with our engines we need optimum velocity and adequate volume.  If we go to big on exhaust, the velocity will drop even though the larger tubing will increase the volume.  The scavenging effect will drop and the exhaust pulses will "bunch up" and the vacuum the engine needs to get combustion charge into the cylinder will drop - power-poop-out!!

The trick is to get optimum velocity AND optimum volume. In my experience the 22R seems to respond well to header exhaust modifications.  My 22REs seem to be more sensitive to exhaust velocity and flow - "backpressure"!

I think it is generally accepted that tri-Y designed header creates better velocity for low to mid range torque and 4-in-1 header design creates more top end RPM power.  After selecting the header, the exhaust pipe diameter to cat and to muffer, and the muffler style can have additional effect on optimizing exhaust performance.

Like other topics, this one can be controversial.

Again, that just my worthless opinion and very elementary understanding of backpressure.

Gnarls.

[Gnarly4X]

I didn't know there was 85.5 octane gas?  The compression number I found for the 20R is 8.5?  The compression ratio for the 22R is 9.0:1??  I guess the lower compression of the 20R runs on the lower octane fuel.

Gnarls.

[blackdiamond]

I didn't know there was 85.5 octane gas?  The compression number I found for the 20R is 8.5?  The compression ratio for the 22R is 9.0:1??  I guess the lower compression of the 20R runs on the lower octane fuel.

Gnarls.

85 is considered regular grade in Colorado where the elevation is higher.

[Gnarly4X]

85 is considered regular grade in Colorado where the elevation is higher.

Geezz... I need to get out more and do some traveling to other states!!  Unfortunately I missed several awesome 4-wheel drive trips to Colorado before I totaled my '85.

Gnarls.

[Gnarly4X]

Here's a graph of a stock 22R vs a 22R with a stock 20R head.

Gnarls.

[Auggydog]

 Great info,after all the reading,I'm going to replace my cam.I'm running 5:71and 5speed with 20r,on 35's,runs great off road,falls on it's face at freeway speed.
From rpm charts,my set up is real close to same rpms as stock gears tires and 4 speed.

[Gnarly4X]

Great info,after all the reading,I'm going to replace my cam.I'm running 5:71and 5speed with 20r,on 35's,runs great off road,falls on it's face at freeway speed.
From rpm charts,my set up is real close to same rpms as stock gears tires and 4 speed.

Hi Auggydog,

What cam are going to go with?

What exhaust are you running or going to run?

The reason I'm asking is because from some testing I've done recently with the 20R head, some cam profiles don't seem to show much change and could actually cause deficiencies in flow from the stock 20R cam, depending upon the exhaust system.... but that data is just what my software is showing after some quick tests.  I'm not yet sure what is causing those numbers.

Gnarls.

[Gnarly4X]

UPDATE 8-21-2016:  Cam Compare - 20R - see attached Excel sheet.
Please let me know if you cannot download and view it.

Well, I finally was able to do some mock pulls and transfer the data to an Excel sheet.

For those interested, please review and let me know what you think. 

Gnarls.

[emsvitil]

I like the headers with the stock cam.............

[Gnarly4X]

I like the headers with the stock cam.............

Hey emsvitil,

Yeah... that looks like what has been generally predicted that you should get about a 10% bump in torque and HP numbers with a good torquey header and not-too-big exhaust modification.

What's interesting is the nice RPM range you get, right in a sweet spot for freeway cruising.
 
Gnarls.

[79coyotefrg]

 

with the 20R head remember it is a hemi

[79coyotefrg]

I finally managed to get my dyno program to work.

these specs are what I had written down in my old LCE catalog

[Gnarly4X]

I finally managed to get my dyno program to work.

these specs are what I had written down in my old LCE catalog

Hi 79coyotefrg,

I think those specs are off? 

Isn't the 22 head considered a hemispherical?

Interestingly, the Engine Analyzer shows better numbers for the wedge head over the hemi head selection for the 20R.

Gnarls.

[H8PVMNT]

Interesting how the 20r seems to like the exhaust upgrade so much on paper.  My header is broken off right at the Y pipes right now and I had no trouble doing 80 on the way to work today with 32s and stock gears.

My 22r on the other had seems to like more restrictive exhaust based on actual driving.  I think though that the 22r exhaust anomaly has more to do with how my stock aisan carb works than anything.  If I was running weber I suspect I would be getting different results.

[Gnarly4X]

Tuning exhaust performance is very complex.

The cam profile, especially overlap and cam timing, can affect exhaust systems.  I imagine most of us that have modified our engines with larger valves, porting and polishing, cam, header, and larger exhaust pipe, free flow mufflers, don’t really understand what changes have occurred to flow and volumetric efficiency, and what affects those changes make in the ultimate desire for increase power.

Are the headers we buy equal length?  What lengths are best for a 22R and 22RE?  Why does a tri-Y design scavenge better?  Does it scavenge better at WOT or partial throttle?  I believe exhaust tuning has been historically trial and error.  Is the testing done at WOT or a range of RPMs? There are physical “things” going on that may not be easily measured or even calculated.  Can you measure swirl on a flow bench? Can you measure the pulses at each tube and at the collector? Can you measure the sonic wave caused by exhaust pulses?  Can you measure the mass flow at WOT (wide open throttle)?  What affect does increased compression cause?  How about the number of angles and cut degrees on the exhaust valve?  How about the AF mixture – wave velocity changes depending upon a lean or rich mixture.

The size of the exhaust tuning from the collector back can be critical to maintaining the performance gained by the header and the cam.  Is the tubing mandrel or crimp bent?  Does a 2.0” diameter flow better than a 2.5”?

Lots to think about and more that I will most likely never completely understand.

Gnarls.