Author Topic: Cams and compression  (Read 4318 times)

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Gnarly4X

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Re: Cams and compression
« Reply #120 on: Aug 20, 2019, 08:00:59 PM »
.... What do you guys think is a good camshaft for bottom end and passing grunt for the 22re with a free flowing air filter and headers with turbo exhaust? I would also like to ad it needs to work well with the stock eco. Thanks

G....

Can you open a Microsoft Excel .xls spreadsheet?

Gnarls.
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

sirdeuce [OP]

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Re: Cams and compression
« Reply #121 on: Aug 21, 2019, 12:49:09 PM »
With the stock ECU I'd say look for a cam with close to stock duration with a deal more lift, the stock ECU seems to not like much change. The higher lift would act to give a better torque output. A little more duration will come along with the increased lift extending the powerband a bit as well. Might consider relocating your battery so the AFM can take it's place. Moving the AFM will get the air ducting away from the hot radiator and get rid of that odd shaped restrictive intake duct. Cooler air and better flow will always help out. Best bet for better passing is to match your gearing to the tire size though. Information not given on your truck was the gearing. Biggest power killer is bigger tires on stock gears.
« Last Edit: Aug 21, 2019, 01:00:53 PM by sirdeuce »
Sure it'll fit........ Just needs a little brute finesse.

Gnarly4X

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Re: Cams and compression
« Reply #122 on: Aug 22, 2019, 05:20:32 AM »
With the stock ECU I'd say look for a cam with close to stock duration with a deal more lift, the stock ECU seems to not like much change. The higher lift would act to give a better torque output. A little more duration will come along with the increased lift extending the powerband a bit as well. Might consider relocating your battery so the AFM can take it's place. Moving the AFM will get the air ducting away from the hot radiator and get rid of that odd shaped restrictive intake duct. Cooler air and better flow will always help out. Best bet for better passing is to match your gearing to the tire size though. Information not given on your truck was the gearing. Biggest power killer is bigger tires on stock gears.

That is basically correct.

For a stock 22RE, I would not go to the trouble to move or modify the air intake system.  The gain would be small.

With an RE and Mamma ECU, it appears there is more to consider in the cam profile than just the typical cam specs Lift and Duration.  The other factors or affects, that are measurable and calculated, are almost never openly discussed or published in cam specs.  One is overlap. Another is Lobe Separation Angle (LSA) and how it affects flow and performance.  How important is Dynamic Compression and Theoretical Compression? 

Gnarls.

« Last Edit: Aug 22, 2019, 05:27:52 AM by Gnarly4X »
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

Gnarly4X

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Re: Cams and compression
« Reply #123 on: Aug 25, 2019, 11:18:21 AM »
..... What do you guys think is a good camshaft for bottom end and passing grunt for the 22re with a free flowing air filter and headers with turbo exhaust? I would also like to ad it needs to work well with the stock eco. Thanks

My 1st choice: CompCam 252S
My 2nd choice: Schneider 244-50F
My 3rd choice:  Crane 704-0010 214/224

Before I selected one, I'd have a conversation with Jim at 22RE Performance and get the cam profile on his cam that he recommends and compare it to the other 3 cams.

Gnarls.

« Last Edit: Aug 25, 2019, 02:16:47 PM by Gnarly4X »
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

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Re: Cams and compression
« Reply #124 on: Aug 25, 2019, 12:46:01 PM »
get the cam profile on his cam

I 2nd calling Jim, he'll hook you up. I actually advise buying from him, he puts a lot of love into his cams. He'll tell you that a lot of cams on the market don't play well with the 22RE due to lobe separation, but he has it nailed. I won't speak for him, but I hear he doesn't like to give out the cam profiles too much :)

sirdeuce [OP]

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Re: Cams and compression
« Reply #125 on: Aug 25, 2019, 02:29:09 PM »
I'd like the Schneider 244/50 if the in take and exhaust profiles were reversed. I believe it would do better for low end grunt. After the headers open the exhaust to 2 1/4", including the cat, and play with the fuel pressure a bit. I had a cam from a shop called "the Toy Store". I used a cam that had specs close to the Schneider 244/50 reversed. did really well on an otherwise unmodified engine and perked up quite a bit with exhaust mods.
That was a 20R though without any carb tuning, '75 Celica.
Sure it'll fit........ Just needs a little brute finesse.

sirdeuce [OP]

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Re: Cams and compression
« Reply #126 on: Aug 25, 2019, 02:57:38 PM »
You'd be surprised how much there is to be gained with moving the AFM. Typically, the pipe used to replace the stock crossover pipe will not have the sharper bends, only one mild bend, and would not have the choke points the stock piece has. Plus the throttle response would be better with less volume in the intake tract. My opinion is it is a worth while intake mod. There are a few other bits that can be done but the effort significantly outweighs the gains.
Sure it'll fit........ Just needs a little brute finesse.

Gnarly4X

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Re: Cams and compression
« Reply #127 on: Aug 25, 2019, 04:12:30 PM »
You'd be surprised how much there is to be gained with moving the AFM.

I am not surprised when modifying the air intake on 22R, BUT... .on a 22RE I'd like to see a dyno sheet or "feel" a difference.  I suspect the Mamma ECU is going to modulated the amount of change.  I believe some increase could be had, I just doubt if the amount of work or dollars invested would be worth the gain.

Gnarls.

1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

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Re: Cams and compression
« Reply #128 on: Aug 25, 2019, 04:38:50 PM »

I'd like the Schneider 244/50 if the in take and exhaust profiles were reversed. I believe it would do better for low end grunt. After the headers open the exhaust to 2 1/4", including the cat, and play with the fuel pressure a bit. I had a cam from a shop called "the Toy Store". I used a cam that had specs close to the Schneider 244/50 reversed. did really well on an otherwise unmodified engine and perked up quite a bit with exhaust mods.
That was a 20R though without any carb tuning, '75 Celica.

Do you mean swapping the lift and duration between the intake numbers and exhaust numbers?

Gnarls.


1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

sirdeuce [OP]

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Re: Cams and compression
« Reply #129 on: Aug 25, 2019, 11:49:08 PM »
Do you mean swapping the lift and duration between the intake numbers and exhaust numbers?

Gnarls.




Yep, more lift on the intake. There are a few grinds available for type 1 VWs I'd like to crossover to the 22R/RE, see how they would do.
Sure it'll fit........ Just needs a little brute finesse.

Gnarly4X

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Re: Cams and compression
« Reply #130 on: Aug 26, 2019, 05:06:36 AM »
I played with some numbers...  very interesting!

I don't recall seeing ANY cam profiles where the duration number was higher for the INTAKE.

It takes me some time to run these calculations, so I'll post the numbers later.

Gnarls.
« Last Edit: Aug 26, 2019, 05:16:20 AM by Gnarly4X »
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

emsvitil

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Re: Cams and compression
« Reply #131 on: Aug 26, 2019, 05:16:49 AM »

The reverse dual duration (longer intake) is often done for slant 6's .


You do it when the exhaust side flows better than the intake  (in comparison to chevy motors which cam companies tend to base ALL their cams on)
Ed
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22RE  W56B
31x10.50R15

sirdeuce [OP]

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Re: Cams and compression
« Reply #132 on: Aug 26, 2019, 07:37:13 AM »
One of the reasons the exhaust cam profiles were made longer is to make up for the looser valve lash. On the cam ramp 2-3 thousandths is quite a bit of travel, so, to make up for the loss on identical In/Ex lobes the exhaust was made longer.
Sure it'll fit........ Just needs a little brute finesse.

sirdeuce [OP]

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Re: Cams and compression
« Reply #133 on: Aug 26, 2019, 08:09:22 AM »
You do it when the exhaust side flows better than the intake  (in comparison to chevy motors which cam companies tend to base ALL their cams on)

That's why enhancing your exhaust's efficiency makes such a difference in our 22Rs, the factory exhaust is long with a lot of collapsed bends. Not to mention a tad undersized. You'll always see me saying to improve the exhaust. The intake is where most of the power is made. Most engines have a restrictive intake. The intake charge isn't sucked in, it's pushed in at 14.7psi(N/A of course). It's why port work on the intake nets better gains than in the exhaust. Cam timing also has a greater effect on the intake than the exhaust. Some engines, ehemmm 22R, like to fight against any improvements to the intake without MAJOR portwork. But the 22R was not designed to make power, it was designed for a good low RPM torque output. They did a good job of that!





Sure it'll fit........ Just needs a little brute finesse.

sirdeuce [OP]

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Re: Cams and compression
« Reply #134 on: Aug 26, 2019, 08:14:26 AM »
Maybe another thread is needed for this next thought, cam gross lift relation to valve size. There is a point where lift becomes excessive and can actually be detrimental to port flow by introducing restrictive eddys and turbulence.
Sure it'll fit........ Just needs a little brute finesse.

Gnarly4X

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Re: Cams and compression
« Reply #135 on: Aug 27, 2019, 04:56:37 AM »
 
I'd like the Schneider 244/50 if the in take and exhaust profiles were reversed. I believe it would do better for low end grunt. After the headers open the exhaust to 2 1/4", including the cat, and play with the fuel pressure a bit. I had a cam from a shop called "the Toy Store". I used a cam that had specs close to the Schneider 244/50 reversed. did really well on an otherwise unmodified engine and perked up quite a bit with exhaust mods.
That was a 20R though without any carb tuning, '75 Celica.

I've attached an Excel sheet comparing the Schneider cam with duration numbers swapped.

I'm curious if you think the lower RPMs (below 3000 RPMs) are improved when the duration is higher for the intake?  :dunno:

I'll do another comparison with the LIFT numbers swapped.

Gnarls. :inthedark:
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

sirdeuce [OP]

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Re: Cams and compression
« Reply #136 on: Aug 27, 2019, 01:46:48 PM »
Better cylinder fill at lower RPMs with those #s. Maybe better with a few degrees advance. slightly high compression, a few psi. I have found on a few engines I have done  that putting a little bigger cam on the intake makes a flatter torque curve. Going 6-10 degrees longer duration and more lift will have that effect. getting bigger on the split makes less and less as the split increases. Though I'd say the Schneider 260 grind would do quite well on the intake with the 244 on the exhaust. That and a good exhaust and header. The 250 and 260 grinds both have a 216 degree at .050" lift with the 260 having a milder start to it's opening ramp and a slightly higher lift. I have the 250-60F sitting on the shelf. I'd like to swap those durations.
Sure it'll fit........ Just needs a little brute finesse.

Gnarly4X

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Re: Cams and compression
« Reply #137 on: Aug 28, 2019, 05:02:35 AM »
I'd like the Schneider 244/50 if the in take and exhaust profiles were reversed. I believe it would do better for low end grunt.

So...  the numbers that are posted in the comparison clearly show that there is LOWER torque and HP below 3,000 RPM when the duration numbers are swapped in the Scheider cam.   :dunno:

Am I missing something? :inthedark:

Gnarls.
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

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Re: Cams and compression
« Reply #138 on: Aug 28, 2019, 05:16:44 AM »
One thing I REALLY like about the Schneider 202/216 cam is its extremely flat torque curve all the way to 5,000 RPMs!!  :driving:

That profile should really pull hard after 3,000 RPMs!  :thumbs:

Gnarls. :gap:
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

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Re: Cams and compression
« Reply #139 on: Aug 28, 2019, 05:21:00 AM »
Maybe another thread is needed for this next thought, cam gross lift relation to valve size. There is a point where lift becomes excessive and can actually be detrimental to port flow by introducing restrictive eddys and turbulence.

Oh yeah....  fun stuff....

All we need is a Superflow 902S attached to a Superflow SF-260 Flowbench!!  :dancing:

Gnarls. :spin:
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

sirdeuce [OP]

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Re: Cams and compression
« Reply #140 on: Aug 29, 2019, 09:45:04 AM »
So...  the numbers that are posted in the comparison clearly show that there is LOWER torque and HP below 3,000 RPM when the duration numbers are swapped in the Scheider cam.   :dunno:

Am I missing something? :inthedark:

Gnarls.

I haven't seen the spreadsheet you did, my computer won't open it for some reason. I will say this though, you can't always trust the numbers. There's always something that can send you back to the chalkboard. What parameters did you use? Stock? Modified? Total intake/exhaust flow or just port flow numbers? Bore, stroke, displacement, compression I'm sure, but I haven't seen the spreadsheet. Not being a richard, just wondering.
« Last Edit: Aug 29, 2019, 09:56:57 AM by sirdeuce »
Sure it'll fit........ Just needs a little brute finesse.

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Re: Cams and compression
« Reply #141 on: Aug 29, 2019, 07:22:59 PM »
I haven't seen the spreadsheet you did, my computer won't open it for some reason. I will say this though, you can't always trust the numbers. There's always something that can send you back to the chalkboard. What parameters did you use? Stock? Modified? Total intake/exhaust flow or just port flow numbers? Bore, stroke, displacement, compression I'm sure, but I haven't seen the spreadsheet. Not being a richard, just wondering.


I agree "you can't always trust the numbers."

But unless and until I can see certified engine dyno numbers, I'll trust the numbers from my Engine Analyzer.... as do many top race engine builders.

I've attached a converted .xls sheet to a .jpg... here's the link:  https://imgur.com/x8Z3deH

Gnarls.


« Last Edit: Aug 29, 2019, 07:42:40 PM by Gnarly4X »
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

sirdeuce [OP]

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Re: Cams and compression
« Reply #142 on: Aug 30, 2019, 08:13:19 AM »
Ok, I got that one. The engine descriptions are a little vague. Looks like the swapped durations fall off slightly 'til @2600rpm then overtake the standard cam. From about idle to the 2600rpm there's @4lb torque difference favoring the standard cam. From that 2600rpm point that swaps to the swapped cam 'til about 4300rpm, then they get pretty even for a few hundred rpm. For the lower RPM torque the standard cam looks a tad bit better for sure. Better for cruisin' and crawlin'. I'd say for highway use they're both good, I could go either way. I still like the swapped cam better. I'd kick the timing(cam) about 3* advanced, should drop the peaks 200rpm and reduce that low RPM split.
This is where having a true DOHC engine is great, the ability to change the timing and lobe centers. If it were that way with the 22R I'd just advance the intake and leave the exhaust where it is. That would give me a 107 degree lobe center, if you're using the CARBY specs on that cam, 111 for the EFI spec cam (Schneider offers a choice of carb or EFI cams).
Sure it'll fit........ Just needs a little brute finesse.

Gnarly4X

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Re: Cams and compression
« Reply #143 on: Sep 02, 2019, 06:15:34 AM »
I'd kick the timing(cam) about 3* advanced, should drop the peaks 200rpm and reduce that low RPM split.

I compared 0 degrees and 3 degrees advance on cam timing on your swapped duration, from 1800 to 5400 RPMs.

The 3 degrees advanced increase Pk tq by 1 ftlb from 157 to 158 @ 3,000 RPMs. The Avg Tq stayed the same at 140 ftlbs

Peak HP dropped by 3 HP, from 133 to 130 @ 5400 RPMs, and the average dropped from 96.2 to 95.7

I'll stick with the Schneider spec'd cam.

Gnarls.
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

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Re: Cams and compression
« Reply #144 on: Sep 03, 2019, 04:12:00 AM »
Hey s

I swapped the LIFT numbers (.415/.430) on the Schneider cam to your suggestion Int .430, Exh .415, with duration at 202/216.

The only change was 1 HP increase at 5,000 RPM, all other numbers stayed the same.

Gnarls.

1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

sirdeuce [OP]

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Re: Cams and compression
« Reply #145 on: Sep 11, 2019, 04:07:24 PM »
So, looking at the numbers on your spreadsheet, I believe the Schneider cam with the swapped numbers would make a better cam. At least with my use it would be better. From 1000rpm to 1300rpm less than a 4lbft difference and then from there to 2400rpm about a 2lbft difference both in favor of the unswapped spec. At 2400 things start getting interesting as the numbers are equal to 2600rpm and then the swapped cam starts to overtake the stock specs and doesn't back down, keeping ahead of the stock spec cam for the remainder of the run. The swapped cam would be a better overall use cam. the stocker would do better for a truck that spends most of it's time crawling from idle to just off idle. My truck spends an inordinate amount of time on the highway. Either way, I'd say most travel is done above 2500rpm. I'd be happy to sacrifice that little bit under 2400rpm.
« Last Edit: Sep 11, 2019, 04:21:49 PM by sirdeuce »
Sure it'll fit........ Just needs a little brute finesse.

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Re: Cams and compression
« Reply #146 on: Sep 11, 2019, 04:24:45 PM »
How would you feel about punching in the numbers from the Schneider 250-260F stock and swapped? I have one of those on my shelf. Would be for EFI so the 112 LC would be the spec to use there.
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Re: Cams and compression
« Reply #147 on: Sep 11, 2019, 06:05:17 PM »
How would you feel about punching in the numbers from the Schneider 250-260F stock and swapped? I have one of those on my shelf. Would be for EFI so the 112 LC would be the spec to use there.

I used my rebuild engine specs:

From 1800 thru 5400 in 400 RPM increments:

Stock profile:  Pk Tq = 156 @ 3000, Peak HP = 132 @ 5400 - Avg Tq - 139, Avg HP - 95.6
Swapped Duration:  Pk Tq = 157 @ 3000, Peak HP =134  @ 5400 - Avg Tq - 140, Avg HP - 95.9

To do a 1000 through 5900 in 100 RPM increment comparison would take me about 1 hour.

Gnarls.
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

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Re: Cams and compression
« Reply #148 on: Sep 11, 2019, 06:08:01 PM »
So, looking at the numbers on your spreadsheet, I believe the Schneider cam with the swapped numbers would make a better cam. At least with my use it would be better. From 1000rpm to 1300rpm less than a 4lbft difference and then from there to 2400rpm about a 2lbft difference both in favor of the unswapped spec. At 2400 things start getting interesting as the numbers are equal to 2600rpm and then the swapped cam starts to overtake the stock specs and doesn't back down, keeping ahead of the stock spec cam for the remainder of the run. The swapped cam would be a better overall use cam. the stocker would do better for a truck that spends most of it's time crawling from idle to just off idle. My truck spends an inordinate amount of time on the highway. Either way, I'd say most travel is done above 2500rpm. I'd be happy to sacrifice that little bit under 2400rpm.

That's one of the nice features about choosing a cam profile... you can pick your peaks and curves in the RPM range you need it.

Gnarls.
1986 XtraCab SR5 22RE 5speed W56B, ~26,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

sirdeuce [OP]

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Re: Cams and compression
« Reply #149 on: Sep 13, 2019, 10:20:43 AM »
An hour, geesh. thanks for doing what you did.
Sure it'll fit........ Just needs a little brute finesse.

 
 
 
 
 

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