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As mentioned many times before, air fuel ratio gauges kick ass!
 

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Opeler
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Discussion Starter #102
First, I'm not clear what you mean that you're "trying" to get the carbs perfectly balanced. How are you balancing them? Once properly balanced, they shouldn't need adjustment for quite a while unless you change the placement of one of the carbs, e.g. removal and reinstall.

Second, I don't like suggesting a particular setup because every engine will respond differently, but since you asked......Manual transmission, Jets: 145 Mains, 190 Air Corrector, F8 65 Idle, 50 Pump. 0 Exhaust Bleed (I think). I think the last standard emulsion tubes I was using were F16, I'm using some customer made tubes now. I don't use the cold start circuit. I have an electric fuel pump and let that run for few seconds, then pump the pedal 3-4 times when cold, and it starts immediately. I'm using a Compu-Fire ignition. I'm very intrigued by the ignition you bought but I like NOT having a cap and rotor too much. I'm probably running a little rich and need to put the AFR meter on again, I've made some recent changes.
I have said “trying” because I have been fighting various issues (ie: torn rubber on mounts, vacuum leaks, bad pump jet, etc) causing me to chase other problems down first. I am using the tool pictured below to balance the carbs.

426906


I have them really close, but fine tuning with air bleed screws and my linkage to get it totally perfect. Two young kids and a full time job take my priority time, so
this doesn’t happen as quickly as I would like.

As far as starting goes, I have the electric fuel pump but I usually have to hit the pedal & turn the key a few times to get it going on it’s own. And then it pops/spits a few times until it’s warm. Once it’s warm, it’s a simple turn of the key.

Thanks for your responses. And thanks for sharing the jetting, mine isn’t too far off from that either. I have some spare emulsion tubes, idles and air correctors, just not extra mains or pump jets.

Eric
 

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Opeler
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864 Posts
OK, good. When you said "trying" I wasn't implying that you're not trying, I was concerned that you weren't using a gauge of some sort. Make sure you remove and block the power brake hose when adjusting the balance. When cold, mine usually requires about 3-4 pedal pumps. If you're not using the cold start circuit, then not running smooth until warm would be normal. Mine doesn't sputter but does need feathering of the throttle until warm. IIRC, the Exhaust Bleed made a difference for me and helped with a flat spot while accelerating.
 

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Can Opeler
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3,261 Posts
To further clear up what was said above.

The exhaust bleed is the accel pump exhaust in the bottom of the fuel bowl. You can buy a 00 size one that prevents fuel from bleeding back into the fuel bowl. This means all of your accel pump squirt goes into the engine every time. It helps a lot

Pegasus racing part no. 79701-000
 

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Opel Rallier since 1977
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1,475 Posts
Hey JHJ.... I was re-constructing your engine's static and dynamic CR to see if that could be a factor in your low off-line torque. I guessed at a flat top at zero deck, cam up with 9.6:1 static CR... and then found your final pistons were for 9.5:1. So that agrees well.

Taking you cam and making an educated guess on the cam's ramps from the duration at .050" lift so as to figure out dynamic CR, and with that came up with 7.2:1. That makes good sense with the cam you have and the static CR that you have.... but it does not agree at all with the cranking compression numbers of 180 psi that have been reported. You ought to be seeing in the 135-150 psi range, depending on altitude. May I ask at what altitude you are at, or which general town/city so I can look up the altitude?

Also, I see that you got a new torque converter. Do you know what stall speed they designed it for?

Tnx,
Mark B.
 

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Opeler
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769 Posts
Discussion Starter #106
Hey JHJ.... I was re-constructing your engine's static and dynamic CR to see if that could be a factor in your low off-line torque. I guessed at a flat top at zero deck, cam up with 9.6:1 static CR... and then found your final pistons were for 9.5:1. So that agrees well.

Taking you cam and making an educated guess on the cam's ramps from the duration at .050" lift so as to figure out dynamic CR, and with that came up with 7.2:1. That makes good sense with the cam you have and the static CR that you have.... but it does not agree at all with the cranking compression numbers of 180 psi that have been reported. You ought to be seeing in the 135-150 psi range, depending on altitude. May I ask at what altitude you are at, or which general town/city so I can look up the altitude?

Also, I see that you got a new torque converter. Do you know what stall speed they designed it for?

Tnx,
Mark B.
I’m in Indianapolis area.

You said you’re making an educated guess at cam’s ramps....you lost me there? What info are you trying to get and for what conclusion?
 

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Opel Rallier since 1977
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1,475 Posts
The numerical work is to get to the dynamic compression ratio (DCR) which is the main indicator of your low RPM torque below the 2500-3000-ish RPM range. To figure that, one needs the static CR (SCR, which is the 9.5 number you got from Wiseco) and the intake closing angles (ICA). The ICA that you need is that where the intake is 'effectively' closed, and where the piston is no longer pushing fuel-air mixture back out of the intake valve, but is actually building compression.

That 'effective' ICA is measured in crank degrees and will vary from something like 40-45 degrees ABDC in a stock engine (ABDC = after bottom dead center; i.e. the piston is moving up on the compression stroke), and up to 80 or more degrees ABDC for a radical race cam. That effective ICA will vary some with the steepness of the closing ramp on the cam profile. Usually, an ICA based on the advertised duration numbers will get you close, with advertised duration being typically measured at .006" lift. But I have found that with cam profiles with a slow opening and closing ramp, then you need to use a bit earlier ICA to be accurate.

If you can get the effective ICA close, then you can very accurately predict cranking compression numbers and DCR, and have a very good idea on how the engine torque is going to be at those low RPM's. So based on your cam's .050" lift duration, and figuring it had fairly slow closing ramp, so I added 55 degrees to the .050" lift duration (222+55=277), and worked out the effective ICA. I started doing this in the 70's all by hand, but now I cheat and put it all into a computation tool by Pat Kelley, and then use the Wallace Dynamic CR Calculator tool to see the effects of altitude and get the predicted cranking compression.

Sooo after all that explanation... I came up with an effective ICA of 72 degrees ABDC for you cam assuming a slow closing ramp, and with all the computations it spits out a DCR of 7.2-ish, and a cranking compression of 135-140 psi at 1000' altitidue... and you are close to that altitude in India-no-place. 7.2 is not low but is not high either. It is a bit better than the DCR for a stock smog-era grocery-getter engine. What IDK is the same parameter for a stock 2.2L.

Now the question on the torque converter stall speed has to do with at what RPM it begins to lock up, and that works in with the cam. If you have too low a stall speed with too big a cam, then when you put your right foot down, the torque converter will start to lock up at an RPM below where the engine has come well up on the torque curve and load the engine and not let it rev higher at that moment. The result is a low torque, dragged-out bog regardless of how far you have your foot down, and when the rev's build to where the engine is finally getting up on the torque curve, then it is BOOM... you're off to the races. It is exactly like driving a stick and putting the trannie in too high a gear for the engine's torque curve, and the car bogs before it builds RPM's up to where you get 'on the torque curve', and it finally takes off.

So all of this is just to see if you have a low DCR issue or a TC stall speed issue that is holding the car back at low RPM's, so you can decide if it is in the carb setup or elsewhere. Hope that all makes sense!
 

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But your compression is 180 and you should be good.I would not do anything with the T/converter at this time. Work on Carb. tuning and ign. timing. Keep it simple.
 

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Opel Rallier since 1977
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Yes, guy, I agree that, with 180 psi cranking compression, it ought to be awesome off the line. But this is what bothers me.... I am no longer believing the 180 psi compression readings. I've been computing up this stuff for decades, and consistently make good predictions, and to get to close to 180 psi crank compression, with that cam size, you would need to be pushing up around 11:1 static CR. There is no magic in this build to mysteriously push up the compression readings.

So, I would appreciate knowing the TC stall speed to complete this line of thinking. It is to JHJ's benefit IMHO to hash this out. And IIRC, he has asked the question of 'Could it be something else?' It may not any issue at all. If one of some of us could drive the car one time, we might be able to say 'Oh.... that's definitely a off-idle lean problem.' But through the internet we can only ask questions.
 

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Can Opeler
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Compression readings are to be taken with a grain of salt unless you have a really high end tester. I have three harbor freight gauges and they vary by 20-40psi from each other. They are for testing percent difference between cylinders, that’s all.

Now if you have a Mac tools or snap on one, AND use proper testing procedures (same battery voltage, same number of cranks, same throttle position etc) then you can use it to read your actual psi.
 

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Just Some Dude in Jersey
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Okay, so everyone is leading you down the merry garden path of buying a gazillion gauges and gizmos and bags of jets and electron microscopes and telling you to get into seat of the pants tuning and blah, blah, blah. This sounds like the dreadful experience I had last year with my car. I got a hundred different opinions and followed each one of them and wasted over a $1000 and not one of them did a single thing to fix my car.

For all we know, you may have done everything right, but there's a hidden underlying reason why you're not up and running.

You appear to have 2 mods going on at the same time, maybe 3: A rebuilt 2.2L engine, dual side draft carbs, and, maybe, your new fangled distributor.

One thing that I think my tuner did, in order to satisfy my request for extremely good low speed drivability, was to really throw the gas at the engine. Go really big, like 180+ on the main and go 3 turns out with the mix screw and see what happens or.......

Go back to basics: You liked the performance and off the line tire spinning ability of your Weber 38. I also liked my Weber 38 for all that. Howsabout you put your 38 and oem manifold back on and see how your engine runs. You might have to bump up the mains or idles, I sent you jets that might have the size you need. There isn't that much difference between a 2.0 and a 2.2(I'm guessing that your previous engine was a 2.0), your weber jetting should still be pretty close. If you're running worse than with the 2.0, then take a look at that dizzy. Maybe put your previous oem one back in.

It other words, go back to what you had before and that you know worked pretty good and that you are familiar with when it comes to tuning and timing and such.
 

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Opel Key Master
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Now I have a stock 2.4 with dual 45s, and an automatic...I pretty much bolted on the carbs and sent it. That thing has no problem with the low end spinning tires and such. I'm sure I don't have them balanced, didn't really care, hell the thing was pretty much a rocket even with the transmission. If it was a 1.9 engine, I would look at the torque converter, but your engine should be paired nicely with the stock automatic to be a runner with those carbs. It doesn't appear you are running shorty manifolds so that wouldn't come into play too much with what Rallye Bob mentioned.
Now onto the air box, I had originally 3D printed an air box for the fuel injected throttle bodies, but then after using them on the carbs, which are taller, I just had to build a air box out of steel. I digitally traced the pattern to a DXF format so I could cut it on a plasma, but want to say I just laser cut it out of chipboard to make sure it lined up. and then transferred to a piece of 20g metal. I then formed the top with an English Wheel and fabrication.
426921
426922
426923
 

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Opeler
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Discussion Starter #113
The numerical work is to get to the dynamic compression ratio (DCR) which is the main indicator of your low RPM torque below the 2500-3000-ish RPM range. To figure that, one needs the static CR (SCR, which is the 9.5 number you got from Wiseco) and the intake closing angles (ICA). The ICA that you need is that where the intake is 'effectively' closed, and where the piston is no longer pushing fuel-air mixture back out of the intake valve, but is actually building compression.

That 'effective' ICA is measured in crank degrees and will vary from something like 40-45 degrees ABDC in a stock engine (ABDC = after bottom dead center; i.e. the piston is moving up on the compression stroke), and up to 80 or more degrees ABDC for a radical race cam. That effective ICA will vary some with the steepness of the closing ramp on the cam profile. Usually, an ICA based on the advertised duration numbers will get you close, with advertised duration being typically measured at .006" lift. But I have found that with cam profiles with a slow opening and closing ramp, then you need to use a bit earlier ICA to be accurate.

If you can get the effective ICA close, then you can very accurately predict cranking compression numbers and DCR, and have a very good idea on how the engine torque is going to be at those low RPM's. So based on your cam's .050" lift duration, and figuring it had fairly slow closing ramp, so I added 55 degrees to the .050" lift duration (222+55=277), and worked out the effective ICA. I started doing this in the 70's all by hand, but now I cheat and put it all into a computation tool by Pat Kelley, and then use the Wallace Dynamic CR Calculator tool to see the effects of altitude and get the predicted cranking compression.

Sooo after all that explanation... I came up with an effective ICA of 72 degrees ABDC for you cam assuming a slow closing ramp, and with all the computations it spits out a DCR of 7.2-ish, and a cranking compression of 135-140 psi at 1000' altitidue... and you are close to that altitude in India-no-place. 7.2 is not low but is not high either. It is a bit better than the DCR for a stock smog-era grocery-getter engine. What IDK is the same parameter for a stock 2.2L.

Now the question on the torque converter stall speed has to do with at what RPM it begins to lock up, and that works in with the cam. If you have too low a stall speed with too big a cam, then when you put your right foot down, the torque converter will start to lock up at an RPM below where the engine has come well up on the torque curve and load the engine and not let it rev higher at that moment. The result is a low torque, dragged-out bog regardless of how far you have your foot down, and when the rev's build to where the engine is finally getting up on the torque curve, then it is BOOM... you're off to the races. It is exactly like driving a stick and putting the trannie in too high a gear for the engine's torque curve, and the car bogs before it builds RPM's up to where you get 'on the torque curve', and it finally takes off.

So all of this is just to see if you have a low DCR issue or a TC stall speed issue that is holding the car back at low RPM's, so you can decide if it is in the carb setup or elsewhere. Hope that all makes sense!
I’m wondering about that too. I sent a message to the company that built it to see what it is. I can’t seem to find the paperwork for it so far. I don’t want to guess, but I have an idea of what is was.

But your compression is 180 and you should be good.I would not do anything with the T/converter at this time. Work on Carb. tuning and ign. timing. Keep it simple.
That’s my plan. I know I haven’t tried to jet it further than what it should be according to the Weber book based on my engine specs.
Yes, guy, I agree that, with 180 psi cranking compression, it ought to be awesome off the line. But this is what bothers me.... I am no longer believing the 180 psi compression readings. I've been computing up this stuff for decades, and consistently make good predictions, and to get to close to 180 psi crank compression, with that cam size, you would need to be pushing up around 11:1 static CR. There is no magic in this build to mysteriously push up the compression readings.

So, I would appreciate knowing the TC stall speed to complete this line of thinking. It is to JHJ's benefit IMHO to hash this out. And IIRC, he has asked the question of 'Could it be something else?' It may not any issue at all. If one of some of us could drive the car one time, we might be able to say 'Oh.... that's definitely a off-idle lean problem.' But through the internet we can only ask questions.

Compression readings are to be taken with a grain of salt unless you have a really high end tester. I have three harbor freight gauges and they vary by 20-40psi from each other. They are for testing percent difference between cylinders, that’s all.

Now if you have a Mac tools or snap on one, AND use proper testing procedures (same battery voltage, same number of cranks, same throttle position etc) then you can use it to read your actual psi.
I have a Bosch compression tester. I will do another one today to help satisfy those worried about my numbers. I’m trying to be thorough and go through all possibilities.

Okay, so everyone is leading you down the merry garden path of buying a gazillion gauges and gizmos and bags of jets and electron microscopes and telling you to get into seat of the pants tuning and blah, blah, blah. This sounds like the dreadful experience I had last year with my car. I got a hundred different opinions and followed each one of them and wasted over a $1000 and not one of them did a single thing to fix my car.

For all we know, you may have done everything right, but there's a hidden underlying reason why you're not up and running.

You appear to have 2 mods going on at the same time, maybe 3: A rebuilt 2.2L engine, dual side draft carbs, and, maybe, your new fangled distributor.

One thing that I think my tuner did, in order to satisfy my request for extremely good low speed drivability, was to really throw the gas at the engine. Go really big, like 180+ on the main and go 3 turns out with the mix screw and see what happens or.......

Go back to basics: You liked the performance and off the line tire spinning ability of your Weber 38. I also liked my Weber 38 for all that. Howsabout you put your 38 and oem manifold back on and see how your engine runs. You might have to bump up the mains or idles, I sent you jets that might have the size you need. There isn't that much difference between a 2.0 and a 2.2(I'm guessing that your previous engine was a 2.0), your weber jetting should still be pretty close. If you're running worse than with the 2.0, then take a look at that dizzy. Maybe put your previous oem one back in.

It other words, go back to what you had before and that you know worked pretty good and that you are familiar with when it comes to tuning and timing and such.
I’ve had a 2.2 since I bought it used from OGTS in 2009. I don’t have my original intake manifold or Weber 38, I sold those when I started converted everything over to DSD in 2013, but due to life issues I didn’t run or experience until recently. The distributor is great, no issues there. I believe it’s all in the jetting & balancing of the carb. I sent a message to the place that built my torque converter to see what they put the stall at, because I can’t find the sheet and I don’t want to guess. But at this time, I feel I have more pressing issues.
I do feel that an AFR would be very helpful in tuning this, so I have that on my list of things to get.

Thanks again for all the willingness to offer help & suggestions. This forum is great for that, and I want everyone to know how much I appreciate it. I’m a methodical person by nature, so I’ll take this on in a stepwise approach.
 

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If you no longer have an intake or Weber 38 dgas, I STRONGLY suggest you get yourself a proper air / fuel and try to resolve the issues you have either your current set up
 

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Opel Rallier since 1977
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Good for the methodical approach, JHJ. If I ever have questions on a compression reading, I get another gauge and cross check them. If you get 180 psi again, then that might be something to do. But I can assure you that 180 psi on that cam with a 9.5 SCR is not going to happen, unless something else is awry in the cam department. I just put together a 1.9L with 9.4 SCR and a smaller cam and only get 150-155-ish on the compression readings at 2400' elevation. That's using the same gauge for 40+ years to get consistent results.

Now I have a stock 2.4 with dual 45s, and an automatic...I pretty much bolted on the carbs and sent it. That thing has no problem with the low end spinning tires and such. I'm sure I don't have them balanced, didn't really care, hell the thing was pretty much a rocket even with the transmission. If it was a 1.9 engine, I would look at the torque converter, but your engine should be paired nicely with the stock automatic to be a runner with those carbs.
Keith, my question is on the new Torque converter stall speed. He does not have the stock one anymore.
 

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Opeler
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769 Posts
Discussion Starter #116 (Edited)
I’m totally befuddled, and you’ll see why as you get through this message.

I have done regular compression tests over the last 6 months of getting back to working with this car. They’ve always been near 180, and I know many of you think that number is nuts for getting that reading. But each cylinder was always identical to the other ones. This motor has less than 100 miles on it since the rebuild which was completed about 4 years ago. And of those miles, about 12 of them in the last month around my neighborhood, maxing our at about 50mph. I have ran the motor on a consistent basis in the garage/driveway while I have worked to balance and tune the carbs or just to let it operate. Oil levels have been normal and temperature has remained cool with a shop fan blowing at the nose end of the car while it idles. The only thing that happened that I can think of that would be problematic would be that when I changed out new cap & wires, I put it on 180, and I had a pretty loud backfire when cranking. Aside from that, it’s been idling in the garage or driving around a 2 mile lap of my neighborhood.

So I just did 3 compression tests cycling through all 4 cylinders on a cold motor. I gave each cylinder 5 cranks of the motor, to remain consistent with testing procedures, going from 1 to 4 on each round of testing. Each test on each cylinder produced repeatable readings for that specific cylinder. I did the same on a warm motor, after letting the car idle in the driveway for 10 minutes.

Those readings are:
426925

426926

426927

426928


Warm testing readings are:
426929

426930

426931

426932


1 & 3 are much lower than 2 & 4, what gives?!

The only thing that happened that I can think of that would be problematic would be that when I changed out new cap & wires, I put it on 180, and I had a pretty loud backfire when cranking. Aside from that, it’s been idling in the garage or driving around a 2 mile lap of my neighborhood.
Another frustrating Opel day. Haven’t had a more than a couple good ones in years.
 

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Sorry to see and hear this bud.....

Mite be worth verifying your valve lash on the low cylinders.
 

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Opeler
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Discussion Starter #118
Sorry to see and hear this bud.....

Mite be worth verifying your valve lash on the low cylinders.
Thanks man. I am throwing in the towel for today. I’m showered up and not going to do anything more with it today, other than think/worry what might be wrong. I will be making a list of things to check next based on possible reasons for this disparity. Valves are already on it.
 

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Just Some Dude in Jersey
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14,139 Posts
You've got at least 25% disparity on your compression. Holy schitt. My 2.5 engine had 185 on #1 and 205-220 on the other 3. I had a headgasket leak due to an insufficiently milled head/block. I would suggest lossening your valves 1/2-1 turn on those 2 low cylinders and do the compression test again to see if their numbers go up.
 
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