A bit of engine advise needed.
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Thread: A bit of engine advise needed.

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    A bit of engine advise needed.

    Hi guys
    Im in need of a bit of engine advise from any of you guys that are CIH experts!

    so this is where i am.
    2.4 Frontera engine going into my A series and this is what i have done.
    Bottom end fully rebuilt, crank re-ground, new bearings, new over size Mahle postons (original con rods)
    Head, new bearings, new ENEM cam, new lifter, new rocker studs, new rockers, etc.. original springs.
    New timing chain and bottom gear and vernier gear.
    45 throttle bodies running fully mappable engine manmagement and distributorless.

    I have some break in oil and just need to filler her up and connect everything as waiting for the manifold to come back before i can get her ready to run.

    The engine ECU is just set to a basic map as they didnt have one for a 2.4 CIH funnily enough so it will need taking ot the rolling road and mapping.

    So my main question is the, the engine is all set to TDC and timing check, should i do the initial start up and cam break in like this and then do cam timing when the ECU is mapped? or should i time it up first?

    It currently fillied with standard oil so i could check oil pressure etc.. before i put it back in the car.

    So any feedback/advise or tips would be great as i have spent a lot on the engine so idont want to get it wrong!!

    I have a blog with lots on and have attached a pic. The Opel Project | The Mission – to get to the nurburgring in the Opel

    Thanks
    Andy
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    Set the cam timing now; I can't imagine changing after mapping. Plus, you have plenty to do later.

    Testing the oil pump and oil system on the stand is easy and wise if you are new to this. It is not hard to do again in the car with the break-in oil but probably not necessary.

    With things set up as they are, do you know what the ignition timing will be during the RPM's used for cam break-in? You want some ignition advance to keep engine temperatures down, especially in the exhaust. Check the ignition timing very quickly after start-up to make sure it is right.

    Do you have a way to monitor the AFR to makes sure it is OK?

    Do you know what the valve spring pressures are? (Closed and open pressures)

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    Quote Originally Posted by Manta Rallier View Post
    Set the cam timing now; I can't imagine changing after mapping. Plus, you have plenty to do later.

    Testing the oil pump and oil system on the stand is easy and wise if you are new to this. It is not hard to do again in the car with the break-in oil but probably not necessary.

    With things set up as they are, do you know what the ignition timing will be during the RPM's used for cam break-in? You want some ignition advance to keep engine temperatures down, especially in the exhaust. Check the ignition timing very quickly after start-up to make sure it is right.

    Do you have a way to monitor the AFR to makes sure it is OK?

    Do you know what the valve spring pressures are? (Closed and open pressures)
    i plan to change oil and then prime oil pump again with break in oil in to make sure all is ok and going to see if i can test oil pressure before start up (not sure if its possible when turning over with long extension to drive the oil pump and ignition on?)

    Not sure on ignition timing as its all set by ECU and have to plugin laptop to adjust so i need to find out from the makers before i start her up. I should be able to see RMP etc.. but need to find out a bit more info on timing as it has a basic 2.0l map.

    I know what the the cam advance should be if that helps?

    What is AFR?

    Valve springs are standard frontera 2.4, so i might be able to google the spec, they are not uprated so hope they should be ok? as i presume i need to make sure they are not too strong as they could cause lifter issues if they were?

    I have not done much engne work (apart from building it) so the technical bit is where im lacking knowledge!

    Andy

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    Also the cam spec says
    The inlet valve shall be opened 2,2 mm at TDC in the overlap position at zero clearance.

    So if i have TDC and the cam locator pin is at 12 Oclock, then im at TDC #4 (not 1? as that would be cam locator at 6 oclock?) is this the overlap position?

    Andy

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    Just Some Dude in Jersey The Scifi Guy's Avatar
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    Holy cow, nice looking set up so far!

    Although I'm installing FI on a 2.4, I essentially know absolutely nothing, so I probably can't help you with much of anything seriously technical.

    AFR is air/fuel ratio. Manta dude is asking if you have a way to sample and read what your air/fuel ratio is.

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    Depending on the camshaft, a safe bet to start the engine is 5 degrees BTDC at idle.

    Total timing 28-30 degrees BTDC assuming standard compression ratio too. 2.4’s don’t tolerate nearly as much ignition advance as a 1.9 or 2.0.

    I presume the camshaft is mild based on you using standard valve springs. The standard 2.4 valve springs will coil bind at .475” lift.

    A standard 2.4 makes peak power at 4800 rpms. Even with a modest hydraulic cam I doubt there is any need to rev the engine beyond 5500 rpms. Power just falls off fast above that.
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    Quote Originally Posted by The Scifi Guy View Post
    Holy cow, nice looking set up so far!

    Although I'm installing FI on a 2.4, I essentially know absolutely nothing, so I probably can't help you with much of anything seriously technical.

    AFR is air/fuel ratio. Manta dude is asking if you have a way to sample and read what your air/fuel ratio is.
    Thanks :-)
    Im not an engine type of guy either! saw you were running injection on your as popped a post on your thread about fuel lines.

    Andy

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    Quote Originally Posted by RallyBob View Post
    Depending on the camshaft, a safe bet to start the engine is 5 degrees BTDC at idle.

    Total timing 28-30 degrees BTDC assuming standard compression ratio too. 2.4’s don’t tolerate nearly as much ignition advance as a 1.9 or 2.0.

    I presume the camshaft is mild based on you using standard valve springs. The standard 2.4 valve springs will coil bind at .475” lift.

    A standard 2.4 makes peak power at 4800 rpms. Even with a modest hydraulic cam I doubt there is any need to rev the engine beyond 5500 rpms. Power just falls off fast above that.
    Hi Bob
    Thanks for the info. I will need to get info from the kit maklers as its a fully mappable ECU and they have set it to what they call a standard vauxhall 2.0l so im not sure on exactly on the spec. its distributorless so the only manual control ihave is the cam timing. I can plug the laptop in to acces all the parameters so i presume i can adjust from there.

    This is the cam info
    part number 35-42-400 and you will find these data’s (288/276/108/110/11.1/11.2/2.2/1.8/ H) .

    The inlet valve shall be opened 2,2 mm at TDC in the overlap position at zero clearance.

    I stuck with the standard springs as the guy at enem said they would be fine with the cam? and also couldnt afford them after buying the cam, pistons, bearings etc..!
    I also presume i dont want to go too strong for initial start up and cam break in?

    im going for low down power so not planning on trying to get heigh revving so up to 5500 will be plenty.

    I know what i want to do engine wise im just not that technical so need a bit of guidence!

    Thanks for all the info so far and i will post a pic once i have the manifold on and the throttle bodies :-)

    Andy
    Last edited by [email protected]; 08-09-2019 at 03:05 AM.
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    Your cam specs look a little bit mixed up, this is what my old ENEM catalog says: Profile Y12, Duration 288°, Lobe Separation Angle 109°, 11,1mm Lift, Intake valve open at top dead center 2,2mm. ENEM recommends a solid lifter for checking the valve opening at TDC.
    Last edited by Commodåren; 08-09-2019 at 04:27 AM.

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    Quote Originally Posted by Commodåren View Post
    Your cam specs look a little bit mixed up, this is what my old ENEM catalogue says: Profile Y12, Duration 288°, Lobe Separation Angle 109°, 11,1mm Lift, Intake valve open at top dead centre 2,2mm. ENEM recommends a solid lifter for checking the valve opening at TDC.
    thanks for the update. I was only going off the info they emailed me. They recommend setting the cam by using the 2.2mm at TDC, the bit im confused on is this.

    They say set it to 2.2mm TDC on intake in the overlap state with the solid lifter on zero lash. im ok with most but at what point at TDC am i on the overlap?
    At the moment i have setup the TDC according to the manual, so crank located with key at top, pointer on flywheel pointing to the ball, cam gear set with located with the guide (7 o clock) so am i right in thinking im at TDC on number 4 cylinder? and to get TDC on number 1 need to do a full rotation with the crank so the pointer on the flywheel is located and the cam gear is 180 degrees from where it is now?

    Is this then TDC number one and would i be on overlap?

    any duidence would be great.

    Andy

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    The question on the valve springs has to do if they are very strong springs. If they are very strong dual springs, then sometimes the inner spring gets removed for break-in to keep the pressures down on the cam lobe to lifter contact point during break-in. It sounds you do not have that problem, so can proceed with the springs you have as-is.

    Yes, on the AFR meaning. With an unknown map, you are trusting that the programming will keep the engine at a good air-fuel ratio. During initial warm-up most ECU's do not look at the O2 sensor; they just use a preset fuel map for estimating the fuel to inject. So you don't know exactly what you have to start. Experienced guys can pick up from symptoms if the engine starts up too lean or too rich, but for someone new, some aid in knowing the AFR is not too rich may be a good idea. So I guess you are really back to the usual techniques: listening for rough running, looking for continuing blackish smoke out of the exhaust after the initial small cloud of oil smoke, and smelling for a lot of unburned fuel. Firing up a new engine with an unknown carb or FI system is not the best thing to do as you have 2 unknowns; you should try to not stop the engine during break-in while adjust a new carb or FI system. But it sounds like you don't have an alternative.

    Adding an AFR gauge is one thought. The readings take a minute or 2 to become real, but that is better than nothing if you don't have much experience. Ask more about them if you decide to add one. It will be useful long term for tuning so is not a bad investment.

    The idle timing as suggested for 5 degrees ATDC is good, but that is the idle RPM timing and you don't want to be there during break-in. As the engine is running no-load during break-in, and is at elevated RPM's so should be well up on the mechanical advance curve. The ignition timing at those elevated RPM's should be in the 25-30 degree range for break-in. The big thing is to not have a retarded ignition timing.

    Timing check/adjust is number 3 or 4 on my list of things to do immediately after start-up so have the timing light connected and ready to go:
    1. Listen for bad noises!
    2. Look for bad leaks
    3. Check ignition timing.

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    Quote Originally Posted by [email protected] View Post
    thanks for the update. I was only going off the info they emailed me. They recommend setting the cam by using the 2.2mm at TDC, the bit im confused on is this.

    They say set it to 2.2mm TDC on intake in the overlap state with the solid lifter on zero lash. im ok with most but at what point at TDC am i on the overlap?
    At the moment i have setup the TDC according to the manual, so crank located with key at top, pointer on flywheel pointing to the ball, cam gear set with located with the guide (7 o clock) so am i right in thinking im at TDC on number 4 cylinder? and to get TDC on number 1 need to do a full rotation with the crank so the pointer on the flywheel is located and the cam gear is 180 degrees from where it is now?

    Is this then TDC number one and would i be on overlap?

    any duidence would be great.

    Andy
    OK, I understand... you are really just checking cam timing not setting it... unless you have some sort of variable cam or crank sprocket. Do you have a settable sprocket in the system?

    Cylinders 1 and 4 reach TDC at the same instant. So, if you have TDC on 4, you have TDC at 1. But as you are thinking, with one crank rotation, you change from 4 being at overlap to 1 being at overlap. You can tell which is on overlap simply by looking at the valves: both intake and exhaust will be slightly open for the cylinder at overlap.

    You should not trust all the crank markings if you want very accurate cam timing. You should use a piston stop to find exact TDC; here is a video that may help you to understand. Once you know true TDC then you can mark the crank pulley for exact 0 (TDC) and time the cam accurately.

    The note above for using a solid lifter for the timing check is correct. The problem with a hydraulic lifter is that without oil pressure in the system, you don't know for sure if the piston in the lifter is fully pumped up and taking up all the slack in the valvetrain. So, if it is not fully taking up the slack, the valve will not open as far as is should. So do you have a solid lifter on the #1 intake valve for this check?

    Again, this is just a check on cam timing, not actually adjusting cam timing, unless you have some way to adjust the cam or crank sprocket position. If you are truly setting cam timing, then the technique is quite different as well as the tools.

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    Quote Originally Posted by Manta Rallier View Post
    The question on the valve springs has to do if they are very strong springs. If they are very strong dual springs, then sometimes the inner spring gets removed for break-in to keep the pressures down on the cam lobe to lifter contact point during break-in. It sounds you do not have that problem, so can proceed with the springs you have as-is.

    Yes, on the AFR meaning. With an unknown map, you are trusting that the programming will keep the engine at a good air-fuel ratio. During initial warm-up most ECU's do not look at the O2 sensor; they just use a preset fuel map for estimating the fuel to inject. So you don't know exactly what you have to start. Experienced guys can pick up from symptoms if the engine starts up too lean or too rich, but for someone new, some aid in knowing the AFR is not too rich may be a good idea. So I guess you are really back to the usual techniques: listening for rough running, looking for continuing blackish smoke out of the exhaust after the initial small cloud of oil smoke, and smelling for a lot of unburned fuel. Firing up a new engine with an unknown carb or FI system is not the best thing to do as you have 2 unknowns; you should try to not stop the engine during break-in while adjust a new carb or FI system. But it sounds like you don't have an alternative.

    Adding an AFR gauge is one thought. The readings take a minute or 2 to become real, but that is better than nothing if you don't have much experience. Ask more about them if you decide to add one. It will be useful long term for tuning so is not a bad investment.

    The idle timing as suggested for 5 degrees ATDC is good, but that is the idle RPM timing and you don't want to be there during break-in. As the engine is running no-load during break-in, and is at elevated RPM's so should be well up on the mechanical advance curve. The ignition timing at those elevated RPM's should be in the 25-30 degree range for break-in. The big thing is to not have a retarded ignition timing.

    Timing check/adjust is number 3 or 4 on my list of things to do immediately after start-up so have the timing light connected and ready to go:
    1. Listen for bad noises!
    2. Look for bad leaks
    3. Check ignition timing.
    Thanks for all the info. I have had it running on the engine before the rebuild so i know it did fire up ok. It was running rich so probably need to contact the company and see if they can adjust and send me a new map to load up as im not sure what vauxhall 2.0l it is based on and might have been mapped for an engine with better air flow than the CIH. I will see what i can find out. Also need to find out about ajusting the timing on the software.

    Thanks for the help, im learning more stuff each day, so might have the hang of this engine stuff soon :-)

    Andy

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    Quote Originally Posted by Manta Rallier View Post
    OK, I understand... you are really just checking cam timing not setting it... unless you have some sort of variable cam or crank sprocket. Do you have a settable sprocket in the system?

    Cylinders 1 and 4 reach TDC at the same instant. So, if you have TDC on 4, you have TDC at 1. But as you are thinking, with one crank rotation, you change from 4 being at overlap to 1 being at overlap. You can tell which is on overlap simply by looking at the valves: both intake and exhaust will be slightly open for the cylinder at overlap.

    You should not trust all the crank markings if you want very accurate cam timing. You should use a piston stop to find exact TDC; here is a video that may help you to understand. Once you know true TDC then you can mark the crank pulley for exact 0 (TDC) and time the cam accurately.

    The note above for using a solid lifter for the timing check is correct. The problem with a hydraulic lifter is that without oil pressure in the system, you don't know for sure if the piston in the lifter is fully pumped up and taking up all the slack in the valvetrain. So, if it is not fully taking up the slack, the valve will not open as far as is should. So do you have a solid lifter on the #1 intake valve for this check?

    Again, this is just a check on cam timing, not actually adjusting cam timing, unless you have some way to adjust the cam or crank sprocket position. If you are truly setting cam timing, then the technique is quite different as well as the tools.
    Yep got an adjustable vernier timing gear and just bought a dial gague so will be able to check true TDC and hopefully adjust the cam to get the right lift on inlet. Need to dig out some old solid lifter that i hopefully have lying around as have the hydraulic one in for the build up.

    Thanks for all the info, i will do some checking with the engine and looking at the valve lift to see if i can work out which cycle is the overlap.

    Andy

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    Finding true TDC is a good step in accuracy. There is a much better way to set cam timing however, than measuring valve lift at TDC, and the following is the standard way to measure cam timing for performance work:

    Since you have a dial indicator, then with a degree wheel attached to the crank and set so that 0 degrees on the degree wheel is exactly at TDC, you can measure cam timing much more accurately. You find the crank angles at .050" lifter lift on both the opening and closing flanks of the intake lobe, and then compute the angle halfway between those 2 angles. (This procedure assumes a symmetrical cam lobe profile, which is very probably the case here.) This 'halfway between' angle is the ICL, Intake Center Line, and should be at the 108 degree number in your cam's specs. If not, you adjust the cam timing to get that 108 ICL using this measurement technique. (Or you can modify the ICL to a different number for better low RPM torque or high RPM HP).

    Here is a printable degree wheel that you might want to use: I paste this on a thick piece of poster board. A VERY careful and accurate placement of the center hole is important. The Machinery Cleanery Universal Timing Disc, Degree Wheel, Downloadable - Goniometro per Messa in Fase dei Motori a 4 Tempi -

    And good on the FI system having run before. A little rich might be OK, but too rich and you may end up with excess fuel down the cylinder walls and rings, and that does not do them any good. Again, you are sort of flying blind, and an AFR gauge would be a a good thing IMHO.
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    The lift at TDC method can't be that bad since the majority of European cam makers use it for checking purposes. There are after all at least three different head deck heights from the factory, and not to mention milling done when rebuilding or stretched cam chains, so it is important to check the timing, be it with a degree wheel or with the lift at TDC method.

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    No, it is not that bad, but it is not as accurate because the rocker geometry is involved. Rocker ratio is not a constant through the rocker motion. In the case of roller rockers in particular, the rocker ratio decreases when you are not around mid-lift of the valve. So unless the cam manufacturer uses the same valvetrain as you, and set up in the same way, then you can easily get inaccuracies measuring at the valve.

    Any method of measuring off of the lifter will eliminate any valvetrain effects on the cam timing accuracy. The lifter is the best measurement point if you care about best accuracy.

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    This falls under the category of on line chatter a bit I suppose since you’ve already received good advice on the subject. I too am a firm believer in first finding true TDC if the head is off I found the dial indicator was the most accurate, if not then the piston stop method works I tried both, fortunately the ball on my flywheel was spot on. I did mark the front pulley at TDC too but I think the size of the flywheel provides better accuracy. That said next degreeing the cam using the 9” Comp Cams degree wheel worked very well using a dial indicator on a solid lifter to check lift & duration at .050, opening and closing events. Important to be sure that the dial indicator is aligned perfectly with the lifter. Checking the same measurement several times to be sure to come up with the same number then recording them, then doing the math to come up with the centerline. I’m no mechanic either but when I put it together I was curious to learn and know exactly what I was putting together. In fact I found some runout on the cam lobes during all of this and got it corrected (hydraulic valves are sensitive to this). No guessing after I started the engine, I used an adjustable sprocket to dial in the cam card, if anything goes wrong like uneven lifter wear I have actual numbers to refer too. I just wanted to back up from my own experience what I’m reading on your thread. Some might say it’s overkill but my head removal & rebuild 25 years ago I drove around 5-6 degrees retarded due to the resurfacing of the block & head and my own dumb decision for not replacing the timing chain. I just lined up the dimple on the stock cam sprocket and drove around for years with lower cranking compression as well as low end torque, heck I didn’t know any better I was scared stiff of removing the head and re installing it back then. Since the Verneer sprocket is a handy toy to have it sounds like you’ll be at least dialing in your cam numbers. Easier to do out of the car where you can get a straight on view of the degree wheel but doable in the car with the radiator and water pump out too. Lots of good threads on the subject. Just Google cam degreeing instructions and the first ones to come up are reliable articles put out by the reputable manufactures of well known aftermarket cams.
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    Thanks for all the advise.
    The cam comes from these guys https://www.enem.se
    and they do do a fair bit of Opel CIH stuff and do recommend the lift setup for their cam.

    I had the engine all setup on the stand for TDC but needed to get it back in to sort out some other stuff and probably should have waited to set it all up before putting it back in!
    The a series is relatively easy to lift the body off so i could pull it our and setup or i support the lift option is the easier with the engine in the car?
    I could maybe set it up tjhis way and then try and cross reference it with the degree wheel?

    I have a bit more space on the engine at the from as dodnt need to run aircon here in the UK!!

    Need to dig out that solid lifter!

    I like the com cams stuff but find it very hard to get in the UK not many places stock it. I did get their cam lube and break in oil from a place over here that does lots of V8 stuff, so might call them up and see if they do it.

    Never worried about pulling things apart and i expect to someone who does this for a living the whole timing thing is quite easy but its just understanding it and all the little bits that get left out as people presume you knwo the basics and shorted descriptions!!

    I have watched a few good videos and understand the baisc principle, its when you find out that you have set TDC and it menmtions noting in the book about it being number 4 and not 1 on the Opel engine!! so these forums are really useful. I think i need to lidt the valve cover and do some fiddleing about so i can see it all workign and then i will probably work out the overlap etc..

    Any more advise is always welcome as you can never learn too much :-)

    Andy

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    Quote Originally Posted by Manta Rallier View Post
    Finding true TDC is a good step in accuracy. There is a much better way to set cam timing however, than measuring valve lift at TDC, and the following is the standard way to measure cam timing for performance work:

    Since you have a dial indicator, then with a degree wheel attached to the crank and set so that 0 degrees on the degree wheel is exactly at TDC, you can measure cam timing much more accurately. You find the crank angles at .050" lifter lift on both the opening and closing flanks of the intake lobe, and then compute the angle halfway between those 2 angles. (This procedure assumes a symmetrical cam lobe profile, which is very probably the case here.) This 'halfway between' angle is the ICL, Intake Center Line, and should be at the 108 degree number in your cam's specs. If not, you adjust the cam timing to get that 108 ICL using this measurement technique. (Or you can modify the ICL to a different number for better low RPM torque or high RPM HP).

    Here is a printable degree wheel that you might want to use: I paste this on a thick piece of poster board. A VERY careful and accurate placement of the center hole is important. The Machinery Cleanery Universal Timing Disc, Degree Wheel, Downloadable - Goniometro per Messa in Fase dei Motori a 4 Tempi -

    And good on the FI system having run before. A little rich might be OK, but too rich and you may end up with excess fuel down the cylinder walls and rings, and that does not do them any good. Again, you are sort of flying blind, and an AFR gauge would be a a good thing IMHO.
    I have plenty of time so i think i might try both methods and see where i end up. I also need to look into the ECU map and software as it has a Lambada sensor in the exhaust so i would presume i can get a reading from the laptop? and adjust and maybe adjust the timing. The problem with the injection setup i have is there use to be a couple of dealers near me that could map the software but they have all moved away from tuning older cars and now rely on just tuning modern stuff so the actual company that does the is a good 150 miles away and although they have a tech department it more keyed up for tuning companies so everything is alway in tech speak and they find it hard to explain it in basic terms to someone who has no clue on engine stuff and always use short hand for stuff! the plan was to get it up and running and then head up to them as they have a rolling road to get it all setup but i need to get the car runnign and moving first!! I will give them a call and ask them some more questions now i know a little bit more about what i need to ask them about fuel mixure, timing advance etc..

    Andy
    The Scifi Guy likes this.

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