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Über Genius
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I've heard the horror stories but let gas sit, unstabilized for a year or more on many occasions.
My bike went almost two years. Runs fine. Been riding it last two weeks.
 

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Can Opeler
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3,343 Posts
I've heard the horror stories but let gas sit, unstabilized for a year or more on many occasions.
My bike went almost two years. Runs fine. Been riding it last two weeks.
Yeah I’ve run sport four wheelers on 4 year old gas with no stabilizers with no issues. Just gave it the ol smell test. I’ve started up old farm trucks that hadn’t been run in years on old gas too. The only thing I’ve ever had issues with is build up in idle jets on Weber DCOEs when ethanol fuel sits awhile. The main jets on four wheelers and mowers sometimes get a little build up because they are so small, but that can usually be cleared up by covering up the intake and turning the engine a couple times.
 
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Opel Rallier since 1977
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1,919 Posts
Yep and sometimes it will work out OK. But sometimes it won't. And the old gas made many in years past would not go bad nearly as fast the new stuff does so the old farm tuck story is gonna be true sometimes... but sometimes those old farm trucks and machines never start on that old fuel, and people forget that. The emissions mandates and the summer-winter fuels mandated by the EPA in some regions has changed the fuels.

Pull some of that old gas and look at it.. how yellow it has turned is how oxidized it is. And Eric's fuel tank with the gum is obviously the ethanol separation + water problem. If you are in a dry region of the USA, then you won't see that particular problem as readily.

I've had a Jeep engine break a rocker arm due to old oxidized/varnished gas; when fuel gets really old and badly oxidized/varnished, then it can gum on the hot intake valve stems and make them jam open; that was what happened on my Jeep 151 within 50 miles after I dumped in some old gas from my Saab 99! I have another on-line acquaintance who had the same thing happen. And I've had a couple of Stihl carbs and a Honda generator carb have to be replaced due to the gumming; those particular small carbs have very, very fine passages in them that can easily be clogged with the ethanol+water gum.

So just because it does not happen all the time on particular carbs and systems, or that it never happned to your machinery, does not mean it does not happen. If it all keeps working for you, that is good. But don't think it does not happen or is not a problem. It can be hard to believe.... until it happens.
 

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Just Some Dude in Jersey
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14,533 Posts
With all my Opel projects and failures these past 12 years, I've had gas go stale many times. Fortunately, the color change that happens to the gas is a good indicator. When it turns reddish, throw it away. That happens in about 3 months to untreated gas.
 

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Opeler
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1,014 Posts
Discussion Starter #245
I should probably provide an update as to what has been discovered and what the plan is going forward:

Valve springs:
I have spoken with the guy who assembled my motor and learned that the machine shop was the one that installed the valves and springs. He verified that rotators weren't installed in the exhaust pockets. I ended up bringing the car back to my house instead of keeping it there waiting on parts to arrive. So, I have been in contact with a fellow Opeler that helped me understand what to look for and how to take some measurements of installed height of the valve springs. Upon taking measurements, my springs heights are vastly different between the exhaust and intake, which means when the shop didn't install rotators, they didn't install any shims to make up the difference. I'm not sure what they put where at this point. I finally received the package I was supposed to receive on 7/6, but didn't get until 7/27 (thanks for nothing USPS) that included some 2.2/2.4 valve springs that are stronger than stock. Tests have been done on these springs to verify that they will work with the cam I currently have in the motor.

What's next:
I am planning to use the cam I currently have in the motor, I don't see the point of abandoning something that I haven't really gotten to experience yet. I mean, since the motor was rebuilt, Ive driven the car less than 100 miles and in that timeframe I have dealt with 4 vacuum leaks, improperly installed valve springs, ignition timing issues, bad pump jet on a carb, improperly tuned & balanced carbs (which the spring failures further complicated!) just to name a few. So, I'd like to experience this camshaft in my motor at its best before making a decision to go in another cam direction. How am I going to make the car its best? By installing the proper valve springs in the correct manner and then installing a Sniper EFI unit.

I've got the Sniper unit here now and many of the other ancillary pieces for the installation. You have seen that I just had my tank cleaned up and I'm about to install an in-tank fuel pump for the EFI set up. I'm installing a Sniper Retrofit unit, which requires me to cut a small hole in the tank and it installs with a self locking flange, and even can be used with tanks with ribs up to .28" without flattening the metal or filling it in. Once this is all installed this will give me the best possible situation to evaluate the cam choice.

Eric
 

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Opeler
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1,014 Posts
Discussion Starter #246 (Edited)
Update:

My car is heading to the shop to have the valve springs replaced this week. Once that is done I can start to move forward on many of the other items.

I’ve had the car up in jack stands for the last week taking car of some under car issues, like replacing the detent cable for my auto trans, as it was leaking from the insertion point and the cable itself, due to a crack.

While under there, I’ve realized what a cobbled up mess my exhaust system is. I took some measurements of the pipes used tonight, and it should have been no surprise that they are all messed up and different than they should be.
I took exterior measurements of the circumference of the pipes and divided by 3.14 to get the diameter. Here’s what I’ve got:
Main pipe after collector: 2.75”
Muffler: 14” (L) x 10” (w) x 4” (h) it’s stamped with generic numbers on top & “made in china”
Pipe after muffler going over exhaust: 2.5”
Split Y pipes to tips: 1.5”

After reading countless threads in exhaust touting and sizes, and the performance of different choices - this is WAY wrong. And could be yet another contributing factor to my lack of low end torque.
The one thing I couldn’t really figure out, when the over the axle pipe splits to the tips, what size pipe should those two pipes be? Still 2 1/2”?
I plan to have a new exhaust system installed after I get the car running. I don’t like how far down the exhaust hangs below the car, and I HATE the sound of it as I’m driving. It has a terrible drone that will give you a headache at cruising and make it impossible to hear the radio or to talk with a passenger. I do like how it sounds at idle, it’s low and rumbles nicely, but as soon as I give it gas, it’s got a sound that I don’t find pleasant.

These videos are from several months ago, before I diagnosed improperly installed and weak valve springs.



 

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Opel Rallier since 1977
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1,919 Posts
Your idle and initial, low RPM acceleration sure sound like a cylinder miss/weakness, and possibly an exhaust leak up near the engine.
 

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Just Some Dude in Jersey
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14,533 Posts
Well, many guys would kill to have a throaty sounding exhaust like yours. My exhaust also sounds similar, although a tad cleaner.

As far as diameter, RallyBob suggested I use 2.25" piping/muffler for my non-cam-upgraded 2.5 engine, for best power. If I had ported and cammed it, he would recommended a 2.5 exhaust for best power. Going too big can reduce your power. Your system is all screwed up with the sizes. I suggest going 2.25" all the way back to the split Y for the tail pipes. As long as your individual Y pipes combined diameter exceeds 2.25" you'll be good. You will no doubt end up with something like 1.5"-2" individual tail pipes, so no problem. Just have a decent muffler shop redo the whole thing for you and try to get it all made out of stainless, so that you don't have to replace any of it any time soon.

I have a stainless Flowmaster and these really excellent tips that I picked out of a catalog at the Meineke I took it to.

The hard part to get made well is the headpipe. Since I'm choosing to use the stock cast iron 2.4 manifold, I needed a well made custom headpipe configured for a GT. RallyBob made that for me, the rest was made by the muffler shop. I'll be putting my previous 2.5 engine in my new gull wing car and I'll need a manifold for it, so I will most likely choose to use the new Shorty header. I don't know if OGTS offers a 2.25"-2.5" headpipe to go with that, for us 2.4 guys. I suspect not. I would then, therefore, give a muffler shop a stock headpipe and somehow find a flange and have them configure a 2.25" headpipe.
As you might have noticed, the stock headpipes have two approximately 1.5" or so pipes that combine to the 1.625"-2" pipe that goes to the muffler. Both of those pipes should have enough flow for a 2.4, although bigger would be nice. You would just need the pipe going to the muffler to be replaced with something bigger.
 

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Opeler
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1,014 Posts
Discussion Starter #249
Your idle and initial, low RPM acceleration sure sound like a cylinder miss/weakness, and possibly an exhaust leak up near the engine.
I should have prefaced those videos by saying that was me driving it in April, when I was diagnosing issues...before discovering my weak and/or collapsed valve springs.

When I took the header off, I found black discoloration on the header flange, indicating I did have an exhaust leak too!
 

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Opeler
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1,014 Posts
Discussion Starter #250
Well, many guys would kill to have a throaty sounding exhaust like yours. My exhaust also sounds similar, although a tad cleaner.

As far as diameter, RallyBob suggested I use 2.25" piping/muffler for my non-cam-upgraded 2.5 engine, for best power. If I had ported and cammed it, he would recommended a 2.5 exhaust for best power. Going too big can reduce your power. Your system is all screwed up with the sizes. I suggest going 2.25" all the way back to the split Y for the tail pipes. As long as your individual Y pipes combined diameter exceeds 2.25" you'll be good. You will no doubt end up with something like 1.5"-2" individual tail pipes, so no problem. Just have a decent muffler shop redo the whole thing for you and try to get it all made out of stainless, so that you don't have to replace any of it any time soon.

I have a stainless Flowmaster and these really excellent tips that I picked out of a catalog at the Meineke I took it to.

The hard part to get made well is the headpipe. Since I'm choosing to use the stock cast iron 2.4 manifold, I needed a well made custom headpipe configured for a GT. RallyBob made that for me, the rest was made by the muffler shop. I'll be putting my previous 2.5 engine in my new gull wing car and I'll need a manifold for it, so I will most likely choose to use the new Shorty header. I don't know if OGTS offers a 2.25"-2.5" headpipe to go with that, for us 2.4 guys. I suspect not. I would then, therefore, give a muffler shop a stock headpipe and somehow find a flange and have them configure a 2.25" headpipe.
As you might have noticed, the stock headpipes have two approximately 1.5" or so pipes that combine to the 1.625"-2" pipe that goes to the muffler. Both of those pipes should have enough flow for a 2.4, although bigger would be nice. You would just need the pipe going to the muffler to be replaced with something bigger.
I failed to mention that I am using a ceramic coated header from OGTS.

After reading all the exhaust threads I could find, it seemed like a warmed over engine or a larger displacement one (2.2 or 2.4) could use 2.25” pipe throughout. I know Keith (opelspyder) has mentioned he doesn’t like to exceed 2.25” on any system.

So the two individual tail pipes will be smaller diameter ones and not 2.25” each?
 

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Just Some Dude in Jersey
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14,533 Posts
They are splitting the flow of the single 2.25" main pipe, so no need for them to be 2.25" each. Plus it can be hard to get tips that are that slightly weird size. Keep in mind that the bigger the pipes, the harder it is to bend them at the sharp bends needed for our cars, especially over the axle and on back.
 

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Opeler
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1,014 Posts
Discussion Starter #252
They are splitting the flow of the single 2.25" main pipe, so no need for them to be 2.25" each. Plus it can be hard to get tips that are that slightly weird size. Keep in mind that the bigger the pipes, the harder it is to bend them at the sharp bends needed for our cars, especially over the axle and on back.
It’s funny you say it can be hard to find tips that “slightly weird size” because there’s a TON of 2.25” tips. I’ve actually got a couple sets on order now to see how they’ll look in the rear of the car. Smaller than 2” is hard to find, especially ones that aren’t just straight pipes.

Good tip (no pun intended) on the pipe size and bending ability back there.
 

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Opel Rallier since 1977
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1,919 Posts
I should have prefaced those videos by saying that was me driving it in April, when I was diagnosing issues...before discovering my weak and/or collapsed valve springs.

When I took the header off, I found black discoloration on the header flange, indicating I did have an exhaust leak too!
There ya go.. that makes sense!

While I would not worry over keeping 2.25" to the 2 tips, I don't see where it hurts anything....
 

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Opeler
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1,014 Posts
Discussion Starter #255
Two inch pipes with free-flow mufflers are good for at least 150hp. Too much diameter only makes excessive noise.
thanks for the comment. Based on what I’ve read, a 2” is pretty standard and you can go up to 2.25” with a larger or higher performance engine. I’m not a high HP or high RPM guy, I like low end performance and cruising quickly from place to place. Again, based on what I’ve read smaller pipe favors low end power, but don’t want to choke down the engine either.

Otto mentioned many times that using thicker 14 GA pipe can help too. I’ve been researching mufflers that can free flow, but also have a low tone and not the constant exhaust drone.

There also seems to be conflicting opinions on resonated exhaust tips, some people think it tames the sound down and other feel that it makes it louder.
 

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Opeler
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1,014 Posts
Discussion Starter #256
Update:

The car is at the shop having valve springs installed.
I had to scramble a bit, but finally got some stock 2.2 exhaust valve rotators thanks to Bob and springs thanks to John. The machine shop that did the head work 5 years ago didn’t reinstall rotators, and didn’t give them back either, which is odd. They just stuck all the springs in against the head and installed retainers on the tops. Obviously my spring heights were all over the place and so were the spring pressure. I used Pioneer 925-4 springs, which I think were best suited for 1.9 engines and not the raised port heads engines like I have, which may have further exacerbated the issue.

I’m picking up my Intake manifold today from another shop. it’s a Cannon intake manifold, I had the mounting flange machined off and one of Bob’s 2.2/2.4 flanges welded on.

It’s getting closer little by little. I’m just glad I’m discovering the issues and while it stinks that all this has happened, I’ve been able to grow my knowledge of the car and get really familiar with all of it after having it sit in a garage for years.
 

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Opeler
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1,014 Posts
Discussion Starter #257
Update:

I got the car back from the shop yesterday. Everything went together smoothly and without issue.

There was a couple of things that were a surprise:
1) exhaust rotators WERE used and installed.
2) the springs that were used were extremely short compared to the stock 2.2 springs.

I used Pioneer 925-4 springs which have been widely discussed on here over the years, and were recommended by some of the most trusted members on the site. However, while they may be a drop in for 1.9 motors, they sure don’t appear to be a good option for the raised port heads. As you can see from the picture, they are substantially shorter than a stock 2.2 spring.
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Throughout all this, I spoke to several trusted sources and learned some things along the way, which I couldn’t be more thankful for. One of the things I want to share is that OGTS doesn’t sell true 2.2/2.4 springs. They sell 1.9 intake springs to be used for 2.2/2.4 head. Gil mentioned that these springs are only good to about .430 lift on solids and .420 on hydraulic lifters. However, true stock 2.2 springs are good to .475 lift. So if anyone is rebuilding a true 2.2, please source stock springs from somewhere (Enem carries them new) and save yourself from the trouble I’ve dealt with.
 

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Opeler
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1,014 Posts
Discussion Starter #258 (Edited)
Update:

I’m finally starting to make some tangible progress on my Sniper 2300 install.

Prior to tackling all the Sniper related things, I was sick of seeing drops of transmission fluid under the car. The main culprit was a leaky kickdown cable (which seemed to have electrical tape around it?!?) , so I replaced it with a new one and also took the pan off. Flattened some of the irregularities out and installed a new ruler and gasket, and finally used the proper torque setting for the bolts. Fingers crossed that does the trick!
Back to th Sniper, over the last few weeks I have ran new hard fuel lines under the car for the feed and return fuel that EFI needs. I have also completed the Holley Sniper In-Tank fuel pump install in the tank. The last fuel related components are to connect the lines from the tank to the hard lines under the car, and I’m drilling new holes to allow proper clearance and grommets to be used for those.
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I also have installed the O2 sensor for use with the Sniper, this clamp on version will be a temporary solution as I am having the exhaust redone after the car is running again. The exhaust will be sized correctly, not be crooked and will have a permanent bung welded in place.
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I’ve also began construction of a fiberglass air cleaner hat, its rough right now, but it clears the Sniper unit and fits under the hood. Some bondo, sanding and paint should get me in business there.
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I am using a Cannon intake manifold that is already set up for a Holley carb. I had the original mounting flange cut off and the RallyBob raised port flanged welded on. I port matched the intake and the flange to smooth out the transition between the two. I am to the point now of trying to figure out how to actuate the throttle linkage. The Cannon intake positions the Sniper further away from the motor and rotates the Sniper compared to how a Weber would sit, leaving the throttle linkage towards the front of the car. I also use an automatic transmission and need to retain the kickdown functionality, so I can’t delete the original pedal arm. Any suggestions on how to accomplish this??
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If I can get these fuel connections wrapped up soon, then all I have to do is wire things up and sort the linkage out before firing this up again.
 

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Opel Rallier since 1977
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1,919 Posts
Someone recently (within the last month) posted a pix of a throttle setup using a cable rather than a mechanical linkage. That would be good to find and read about.

A word of warning based on direct experience and after viewing questionable welds on the top side of your exhaust connection joints: ANY small air leak into the exhaust can throw off the O2 sensor readings.... sometimes waaay off. Since the Sniper runs in closed loop mode after warmup, errors in O2 sensor readings are going to throw it all off. So once you get this started and you run it about 30 minutes and the Sniper has started to learn, I'd be pulling the spark plugs to read them, and make sure the system is running reasonably clean.

Extra air leaking into the exhaust will cause lean readings from the O2 sensor, and the system will make the mixture excessively rich to try to make the O2 sensor readings look normal. I just recently put an O2 sensor on my Opel in about the same place as yours, and unlike every other O2 sensor installation I've done before, this one is showing severe lean errors. It is reporting max lean (AFR = 22.4) almost all the time.

The cam in my engine is mild, so excess cam overlap is not the cause, and others tests show that the O2 sensor and contoller are fine. I know that my Jetronic system is running both rich and lean at various points, and I should see AFR's above and below 14.7. I found a small leak around the welded bung and fixed that and it improved the readings marginally, but it is still showing AFR=22.4 for 80+% of the time. So I have another air leak further up the exhaust towards the engine; I suspect that it is in the junction of headpipe to manifold, and air is getting sucked into during the low vacuum intervals between exhaust pulses. (My back issues have prevented me from taking it apart to find this leak so far....)

So with that in mind, you may want to think about checking/fixing the exhaust before you try to get this going, or immediately after it is running. I would not want to have the engine running excessively rich for a lot of miles. If bad enough, it will indeed foul the oil with fuel and cause loss of lubrication and excess cylinder wear. (Seen that happen before....)
 

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Opeler
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1,014 Posts
Discussion Starter #260
Thanks for the post, but I don’t know why you think I have a leak and need to get the exhaust fixed before the car is even running....especially from one picture. Don’t get me wrong, I appreciate the O2 sensor tip and don’t plan to drive it for very long before taking it in, but it seems like quite the leap from one picture that isn’t even in great detail from welds done by an exhaust shop. Plus, there’s no way I’m having the exhaust redone without the motor running because the tone can’t be figured out without the motor running and that’s an important factor for me. The car will be running and then to the exhaust shop to be fixed. As I said before, maybe in a different thread, the system is improperly sized and the rear tips are crooked.

As far as the throttle linkage goes, I’m currently plowing through threads on throttle cable setups to see what I can find that will work with that I’ve got going.
 
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