Just installed my tranny and drive shaft and set the pinion angles. I have an IRS rear end, so there is no adjustment on the rear end shaft angle. It is what it is. The only thing to "adjust" is the tranny angle (with shims). However, the pinion shaft is sloping upward .7* while the tranny is sloping downward 1.5*. The driveshaft is sloping downward at .7*. So, my operating angles seem ok. #1 is .8* and #2 is 1.4*. Both are between .5* and 3* and the spread is within 1* of each other.
My concern is the the two shafts (pinion and tranny) are not parallel, nor can I make then parallel since IRS has no adjustment for tilt.
Anyone else have this issue? Will this cause a problem when I start driving? What can be done (if anything even needs to be done)?
No, the situation you have now is not great. You're going to want to shim the transmission to get it parallel with the IRS. I had a similar situation, and here's a thread I had posted with a ton of great input. I ended up having to shim my transmission by roughly 1-1/4" to get everything to line up properly.
MkIV Roadster build: Gen 2 Coyote, IRS, TKO600. Ordered 10/24/18. Delivered 1/29/19. Engine installed 8/8/21. First start 9/12/21. First go-kart 9/17/21. Off to paint 4/11/22. Back from paint 12/30/22. Build thread here.
I just went through this with mine (documented in this post and this post). Different setup w/ IRS + Coyote + T56. For mine, my OA's were too large initially and I ended up having to remove the 0.4" spacers FFR provides between the trans mount plate and transmission body. Many others w/ TKO/TKX have to shim the transmission up like JohnK mentions. Just depends on your setup.
Darryl [dbo_texas]
MKIV #9644 (build thread) (Index)
MK4 Complete Kit | Gen2 crate Coyote | Tremec T56, 3.55 IRS | power steering | hydroboost | dual roll bars | FFR carbon fiber dash | 18" Halibrands + Wilwoods | RT drop trunk kit & turn signal | front battery mount | saddle leather Intatrim Stoneleigh seats + interior accents
I have a 1" shim under transmission now to get engine angle to - 1.5* (- is defined to me as sloping down as seen front to back). I tried multiple shims combos to get the u-joint angles acceptable. Besides, I'm not sure there is enough room left in tunnel to raise tranny up to a + .7* degrees (sloping up) without top of tranny hitting tunnel cross bars.
Shimming is the easy part, what's really confusing me is why would my differential shaft be at + .7* (sloping up)? Since there is no adjustment, shouldn't the mounting points manufactured in the jig at FFR give me a - angle to match the desired - angle of tranny? From what I've read, it's desirable for the engine/tranny to be mounted in a slight - angle (sloping down from front to rear).
Do all IRS's from FFR come angled down when mounted? if not, why would mine be different?
Thank you John K for the links to your journey with this same issue. Very helpful, though still not sure I have enough room to shim up that much higher.
GoDadGo, you sound like my wife!!! She is constantly telling me when I encounter something difficult or puzzling, "You built a plane, this should be easy for you." Believe me, there were many things during the plane build that kicked my butt too!
I had the same issue with my coupe. My guess is it is just tolerances and distortion from welding. I ended up molding custom urethane bushings to correct the problem to get mine to slope down .5 degrees. I tried shims and engine drop mounts, which created other problems. I wonder how many other people are having this issue and if it would be worth molding and selling them as an option? These are the same durometer as FFRs and the material is a polyurethane that is designed for rubber mounts. I know Forte would machine custom aluminum ones, but I did not want to go the hard mount route and have it cause other issues. My only other option was going to have to cut the mounts out and reweld, which I wasn't willing to do. You can see in the photos how much I had to offset the bore angles to correct it. Mine was at .5 up to start.
I had the same issue with my coupe. My guess is it is just tolerances and distortion from welding. I ended up molding custom urethane bushings to correct the problem to get mine to slope down .5 degrees. I tried shims and engine drop mounts, which created other problems. I wonder how many other people are having this issue and if it would be worth molding and selling them as an option? These are the same durometer as FFRs and the material is a polyurethane that is designed for rubber mounts. I know Forte would machine custom aluminum ones, but I did not want to go the hard mount route and have it cause other issues. My only other option was going to have to cut the mounts out and reweld, which I wasn't willing to do. You can see in the photos how much I had to offset the bore angles to correct it. Mine was at .5 up to start.
Thank you so much for reply. Please tell me more!!!! It sounds like others have had same issue. This sounds like the best "fix" of all. How can I get more information from you about how to do this? Or better yet, any chance I could pay you to make me some bushings? Since you've already been down this road, could same me a lot of frustration during the learning curve. I will send you a PM to discuss more.
Shimming is the easy part, what's really confusing me is why would my differential shaft be at + .7* (sloping up)? Since there is no adjustment, shouldn't the mounting points manufactured in the jig at FFR give me a - angle to match the desired - angle of tranny? From what I've read, it's desirable for the engine/tranny to be mounted in a slight - angle (sloping down from front to rear).
Do all IRS's from FFR come angled down when mounted? if not, why would mine be different?
If I understand correctly, your IRS diff is pointed UP toward the front. That is correct. I've done two IRS builds and both were the same. This is all fixtured by FFR, and no reason any would be different. Welding moves things around (like the suspension tabs) but these are solid frame mounts and every one should come out the same. Also, logically this is correct. Normal for the engine/trans to be pointed DOWN. So between the two (engine and IRS diff) they would be roughly parallel. Both of mine came out at 1.4 degrees difference, which is in the acceptable 1-2 degree range. And driven a bunch of miles with no issues. Keep in mind your measurements are all relative, e.g. should be compared with each other. No guarantee your chassis is sitting level, and it doesn't matter if you look at it that way.
Build 1: Mk3 Roadster #5125. Sold 11/08/2014. Build 2: Mk4 Roadster #7750. Sold 04/10/2017. Build Thread Build 3: Mk4 Roadster 20th Anniversary #8674. Sold 09/07/2020. Build Thread and Video. Build 4: Gen 3 Type 65 Coupe #59. Gen 3 Coyote. Legal 03/04/2020. Build Thread and Video Build 5: 35 Hot Rod Truck #138. LS3 and 4L65E auto. Rcvd 01/05/2021. Legal 04/20/2023. Build Thread. Sold 11/9/2023.
Yeah, something similars to it. I used a 90A industrial 2 part polyurethane and made a mold. There are 4 different parts, since the metal sleeve support is different for the front and back, and the horizontal pivot center for the bore is not centered. Made that mistake the first time around.
If I understand correctly, your IRS diff is pointed UP toward the front. That is correct. I've done two IRS builds and both were the same. This is all fixtured by FFR, and no reason any would be different. Welding moves things around (like the suspension tabs) but these are solid frame mounts and every one should come out the same. Also, logically this is correct. Normal for the engine/trans to be pointed DOWN. So between the two (engine and IRS diff) they would be roughly parallel. Both of mine came out at 1.4 degrees difference, which is in the acceptable 1-2 degree range. And driven a bunch of miles with no issues. Keep in mind your measurements are all relative, e.g. should be compared with each other. No guarantee your chassis is sitting level, and it doesn't matter if you look at it that way.
Hi Paul,
It was point down towards the front, the opposite of what we want.
If I understand correctly, your IRS diff is pointed UP toward the front. That is correct.
That's my issue. My IRS shaft is NOT pointing up toward the front (I wish it were). It points down toward the front. Making my two angles 2.2 degrees off parallel. I know it's not optimal, but I don't have enough knowledge / experience with pinion angles to know if this less than optimal difference can be ok for a non-racing "daily driver". Any of the solutions to getting both planes in parallel are not simple, and some not even doable in my frame.
What engine do you have (apologies if I missed it). If you have 1" of spacers at the tranny and it's still pointing down 1.5*, I'd be checking the engine mounts to see if you can get the engine to sit lower.
MkIV Roadster build: Gen 2 Coyote, IRS, TKO600. Ordered 10/24/18. Delivered 1/29/19. Engine installed 8/8/21. First start 9/12/21. First go-kart 9/17/21. Off to paint 4/11/22. Back from paint 12/30/22. Build thread here.
What engine do you have (apologies if I missed it). If you have 1" of spacers at the tranny and it's still pointing down 1.5*, I'd be checking the engine mounts to see if you can get the engine to sit lower.
That's my issue. My IRS shaft is NOT pointing up toward the front (I wish it were). It points down toward the front. Making my two angles 2.2 degrees off parallel. I know it's not optimal, but I don't have enough knowledge / experience with pinion angles to know if this less than optimal difference can be ok for a non-racing "daily driver". Any of the solutions to getting both planes in parallel are not simple, and some not even doable in my frame.
That's surprising and I can't explain the variation between my experience plus others. Just to confirm (and I don't mean to insult...) you mention angles but is the car level? The absolute angles don't matter. Just how they relate to each other, e.g. the differences. How are you measuring? The most accurate engine/trans measurement is on the harmonic balancer. Then subtract from 90. Same for the IRS diff. Best measurement is across the driveshaft adapter. Again subtract from 90. You may want to check with Factory Five. They use CAD software that I'm sure provides the expected build angle and maybe they could explain if yours is different.
Build 1: Mk3 Roadster #5125. Sold 11/08/2014. Build 2: Mk4 Roadster #7750. Sold 04/10/2017. Build Thread Build 3: Mk4 Roadster 20th Anniversary #8674. Sold 09/07/2020. Build Thread and Video. Build 4: Gen 3 Type 65 Coupe #59. Gen 3 Coyote. Legal 03/04/2020. Build Thread and Video Build 5: 35 Hot Rod Truck #138. LS3 and 4L65E auto. Rcvd 01/05/2021. Legal 04/20/2023. Build Thread. Sold 11/9/2023.
What engine do you have (apologies if I missed it). If you have 1" of spacers at the tranny and it's still pointing down 1.5*, I'd be checking the engine mounts to see if you can get the engine to sit lower.
I agree. I remember in discussions about oil pan below the frame rails that there are different height engine mounts available. Convertible mounts are different? I don't remember the details but it is so common to use 3/4 to 1 inch spacer below the trans that it is almost standard. You have that but still have an out of parallel situation.
FFR MkII, 408W, Tremec TKO 500, 2015 IRS, DA QA1s, Forte front bar, APE hardtop.
I am measuring the angles with a digital angle finder placed on the u-joint end caps (which should be perfectly parallel to the shafts). I took the end cap retaining clips out and placed a magnet on the end cap end so the angle finder would be sitting on the end caps and not sitting on the yokes. I double checked those readings against the engine crank shaft pulley and the drive shaft adaptor and they matched! Attached are some pics. These 2 pics show my tranny angle and my rear end angle.
There are 4 objectives to meet with pinion angles. The best I can get is ONLY 2 out of the 4 with tranny shim combos. But with rear end angled up, and with no adjustment, getting them on parallel planes is impossible!
I measured mine relative to the engine and had the same issue. I also measure it realative to the frame, transmission, u joints, and the pinion mounting face. Still had the same issue. Trying to make them parallel caused my drive shaft to be at 11.5 degrees relative and pushed my air cleaner out above the hood. I had to uses ratchet straps to pull the rear mount crossbar back to get mine in, otherwise it was shredding the bushings, so if I had to guess, the rear cross bar relaxed too far foward, and then that pushes the rear of the differential up causing the pinion to point in wrong direction. There's a lot of welding on that piece and it is dangling in the air by only two spots. It would be interesting to measure the angle of the rear mount, realtive to the front mounts, and see how the compare to Randy's.
Do you think it would be possible to get it aligned by making offset bushings?
Consider reaching out to 65 Cobra Dude (Henry) or Mike Everson.
Those guys have built a lot of cars and know them well.
NOTE:..Seeing your most recent pics makes me glad that I went with the 3-Link.
I am having a similar problem. When I raise the tailshaft enough to get it parallel with the pinion shaft (almost 2" above the mount plate) my driveshaft is at 10.5 degrees. The ujoint flange of the pinion shaft is lower than the end where it contacts the ring gear. The pinion shaft angle is 0.8 degrees down.
Offset bushings would be a solution, raising the pinion flange. That would bring it closer to parallel to the transmission output shaft. Is there enough rubber there to get enough offset?
Contemplating such a solution at this point makes my head hurt.
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Jeff
Roadster delivered 8/27/23
Chevrolet Performance LS3 Build Thread
Offset bushings fixed my issue and brought me to .5 degrees down, when looking at it front to back. I was at .5 degrees up or the pinion mounting surface was pointed down at the ground .5 degrees. I am checking with my bosses to see if we can make more and sell them, since I used the equipment we have in our prototype facility.
I am having a similar problem. The pinion shaft angle is 0.8 degrees down.
Jeff, I see your kit was delivered 8/23. Mine was late 23 as well. I'm wondering if FFR has a QC issue on the welding jigs for these mounting points? They say "misery loves company", but in this case, I wish I were the only one with this issue. I'll keep posting as I navigate through this problem to let you know what I find out. I talked to burchfieldb (see post #6) about this. He did have "just enough" to create offset bushings. He is checking with his employer (with the proper tools to make these) to see if they can build a few for guys like you and me. Hopefully this becomes an option. Like you, it makes my head hurt thinking about the "fix" for this.
My kit (delivered Jan 2019) had the IRS pointed 0.9* down at the front, so this variation in IRS mounting points has been going on for quite some time.
MkIV Roadster build: Gen 2 Coyote, IRS, TKO600. Ordered 10/24/18. Delivered 1/29/19. Engine installed 8/8/21. First start 9/12/21. First go-kart 9/17/21. Off to paint 4/11/22. Back from paint 12/30/22. Build thread here.
I am having a similar problem. When I raise the tailshaft enough to get it parallel with the pinion shaft (almost 2" above the mount plate) my driveshaft is at 10.5 degrees. The ujoint flange of the pinion shaft is lower than the end where it contacts the ring gear. The pinion shaft angle is 0.8 degrees down.
Offset bushings would be a solution, raising the pinion flange. That would bring it closer to parallel to the transmission output shaft. Is there enough rubber there to get enough offset?
Contemplating such a solution at this point makes my head hurt.
I went out and measured the thinnest point at 0.140 in the offset bushing.
I am measuring the angles with a digital angle finder placed on the u-joint end caps (which should be perfectly parallel to the shafts). I took the end cap retaining clips out and placed a magnet on the end cap end so the angle finder would be sitting on the end caps and not sitting on the yokes. I double checked those readings against the engine crank shaft pulley and the drive shaft adaptor and they matched! Attached are some pics. These 2 pics show my tranny angle and my rear end angle.
There are 4 objectives to meet with pinion angles. The best I can get is ONLY 2 out of the 4 with tranny shim combos. But with rear end angled up, and with no adjustment, getting them on parallel planes is impossible!
Just as a double check because the camera angle makes it look a little off. If you rotated the angle finder in you first pic 90deg would it read zero? IE; is your driveshaft rotated so the ujoint cap is level? Also, the way I read your angles, you have 1.4 plus .8 = 2.2deg difference between trans and diff correct? I 'think' that would be livable. One other thought to make things easier, can you raise or lower one end of the car so both angles are in the same direction? To me it is easier to think it through if the trans is at, for instance, 5.0 and the diff at 2.8
FFR MkII, 408W, Tremec TKO 500, 2015 IRS, DA QA1s, Forte front bar, APE hardtop.
Just curious, is the left/right angle (view from above) measured? Anyone? Could be that this is assumed to be correct with the engine, trans and diff mounts in "known" positions.
My understanding is that the line formed by the crank, trans and input shaft on the diff needs to be parallel, in all views, but offset to provide the 1 or so degree shift.
Jim
2016 Mk4 Challenge Car, IRS, 3.31 Torsen, RDI Aluminum 427w, AFR 225s, Vic Jr. ProSystems 780 HP, TKO-600 w/Liberty mods. Forward cage. Levy 6/4 piston Wilwoods. Not completed yet, will be a streetable track car.
2004 Superformance MkIII #1855, 2007 Superformance MkIII #2584 purchased in 2012 both sold.
I have been pondering this issue for several days now, trying to come up with a good solution. Here is where I am today:
1.) If we were to measure every production rear drive vehicle on the road today, how much variation from ideal would we see? How many have u-joint issues?
2.) A lot of pickups (not all) have rear leaf springs, which cause a huge swing in u-joint angle variations, especially from empty to fully loaded. How many have u-joint issues?
3.) I personally know of a '71 Charger with a 440 and air shocks (leaf springs) that had a lot of hard launches that never had u-joint issues. How bad were those angles? Likely off-the-charts.
4.) How many short wheelbase Jeeps are raised quite a bit with crummy lift kits that only have issues after many miles of road use? Those angles would make a powertrain engineer apoplectic.
5.) If I had never checked these angles and just bolted together the pieces that FFR gave me would I have problems? No idea, that ship sailed.
The engineer in me wants to make everything perfect. But there is a day in the near future I want to drive this thing. I am going to fab some tailshaft spacers that split the difference and make the best of a less than ideal situation and move on. Future me may regret this decision, but it is where I am today.
Feel free to tell me I'm nuts.
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Jeff
Roadster delivered 8/27/23
Chevrolet Performance LS3 Build Thread
Jeff,
Nuts? Yup, probably but that is almost a given. A fairly widespread condition.
I saw during my SPF days results similar to your analysis listed above. Owners were lifting engines, shifting left to right and angling the driveline to get sidepipes to align nicely, all without regard to the u-joint angles.
Perhaps it isn't the huge concern that many think it is. But I'm still trying to align it as properly as possible. BTW, I measure things for a living, it's a disease.
Jim, and yes, I have the "crazy" certificates.
2016 Mk4 Challenge Car, IRS, 3.31 Torsen, RDI Aluminum 427w, AFR 225s, Vic Jr. ProSystems 780 HP, TKO-600 w/Liberty mods. Forward cage. Levy 6/4 piston Wilwoods. Not completed yet, will be a streetable track car.
2004 Superformance MkIII #1855, 2007 Superformance MkIII #2584 purchased in 2012 both sold.
Jeff,
I TOTALLY relate to your questions! That's exactly where I'm at. The only additional question I have is not related to u-joint wear, but related to rear differential / transmission wear due to the harmonic vibrations since the shafts are not on a parallel plane. I can live with replacing u-joints more frequently. Replacing rear ends and transmissions prematurely seems like the larger risk. Even if I don't "feel" the vibrations (an issue of comfort) am I doing damage to internal gears / bearings by bolting up and moving on? I am in conversation with FFR tech support about this. Sent them some pics this morning. I'll report back their response as soon as they get back to me.
In april of 2023 I posted this in a thread on this same exact topic:
"I am still building (kit delivered in Sept 2022), but for the sake of comparison: My IRS center section pointed down towards the front about .5 degrees (which cannot be adjusted). The trans also pointed down (towards rear) 4+ degrees using the kit-supplied poly mounts for the block and trans. This resulted in a V between the 2 angles with a relative angle of ~ 5+ degrees (which seemed problematic). I used the Levy hard mounts to lower my windsor block a bit and also about 3/4" of spacers under the trans and ended up with a relative angle of around 2 degrees; still a "V" when viewed from the side, but not nearly as severe."
My car graduated in October, I have 1400 miles on it, no issues at all thus far with the driveshaft. I think this 'problem' is very very common, and perhaps nothing to worry about. however I am somewhat curious what the FFR engineers say about it.
<><><><><><><><><><>
Mk4 Roadster complete kit Chassis F5R1010480RD
Ordered Dec 2021, Delivered Sept 2022, First start Mar 2023
Completed October 2023
IRS, Wilwood, 17" wheels, Forte 427W/TKX/EdelbrockEFI
I talked with my employer and their preference right now is to not sell the offset bushings, since I have not tested them yet. They are concerned about any liability with the parts if they fail in use. So hopefully after I get them tested we can sell them.
In another thread I related 30 year old story about a BMW 3 series that had been wrecked and repaired. Car came to the dealer service w/ a complaint about a pulsation at 25-35mph under medium to hard acceleration. Long story short the unibody was bent. We could see the gap front edge of front door to rear edge of fender was a triangle wider at the bottom. It only happened in that speed range and accel level. The dealer body shop put it on the frame straightening machine and fixed the problem. So my thought is get trans and diff as close to parallel as you can and move on. Pretty much anything that might need to be done later really isn't hampered much on a completed car.
FFR MkII, 408W, Tremec TKO 500, 2015 IRS, DA QA1s, Forte front bar, APE hardtop.
I talked with my employer and their preference right now is to not sell the offset bushings, since I have not tested them yet. They are concerned about any liability with the parts if they fail in use. So hopefully after I get them tested we can sell them.
-Brent
I thought I would provide an update on this, there is still a chance that we are going to make the bushings. I looked more into it and the material we are using is production grade and the manufacture said they have other customers using it for suspension bushings. We are checking on what are liability insurance is.
Jeff,
Nuts? Yup, probably but that is almost a given. A fairly widespread condition.
I saw during my SPF days results similar to your analysis listed above. Owners were lifting engines, shifting left to right and angling the driveline to get sidepipes to align nicely, all without regard to the u-joint angles.
Perhaps it isn't the huge concern that many think it is. But I'm still trying to align it as properly as possible. BTW, I measure things for a living, it's a disease.
Jim, and yes, I have the "crazy" certificates.
HAHAHAHA! Yeah, a very common condition. No sane person would do what we are all doing.
I program things that measure things for a living. Yeah, OCD is a mandatory.
It's tough to keep in mind not to let perfect get in the way of done.
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Jeff
Roadster delivered 8/27/23
Chevrolet Performance LS3 Build Thread
Jeff,
I TOTALLY relate to your questions! That's exactly where I'm at. The only additional question I have is not related to u-joint wear, but related to rear differential / transmission wear due to the harmonic vibrations since the shafts are not on a parallel plane. I can live with replacing u-joints more frequently. Replacing rear ends and transmissions prematurely seems like the larger risk. Even if I don't "feel" the vibrations (an issue of comfort) am I doing damage to internal gears / bearings by bolting up and moving on? I am in conversation with FFR tech support about this. Sent them some pics this morning. I'll report back their response as soon as they get back to me.
Please keep us all updated when you hear from FFR. I am very interested in what their opinion is.
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Jeff
Roadster delivered 8/27/23
Chevrolet Performance LS3 Build Thread
Please keep us all updated when you hear from FFR. I am very interested in what their opinion is.
I will.
Took 3 days to get any "response". 1st response came back late yesterday. They said I was measuring my angles wrong. I am not! But I sent more pictures of the same angles measured at different spots to prove my angles were in fact measured accurately (same results at 3 different measuring points). Right now I'm a little frustrated that I had to wait 3 days for the "your doing it wrong" response to my problem.
Well, that's disappointing...
Not a good customer service experience.
Originally Posted by rvanstory
I will.
Took 3 days to get any "response". 1st response came back late yesterday. They said I was measuring my angles wrong. I am not! But I sent more pictures of the same angles measured at different spots to prove my angles were in fact measured accurately (same results at 3 different measuring points). Right now I'm a little frustrated that I had to wait 3 days for the "your doing it wrong" response to my problem.
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Jeff
Roadster delivered 8/27/23
Chevrolet Performance LS3 Build Thread
OMG, this is ridiculous. This is why there are u-joints because the drive line isn't straight. Install the drive shaft and move on, there is nothing damaging about the setup. It's an IRS, the differential doesn't move or change any away of the angles.
Mrk III, 331 stroker, Borla stack injection, T5, 3:55 IRS, Power steering and brakes. Kleiner body & paint
Just installed my tranny and drive shaft and set the pinion angles. I have an IRS rear end, so there is no adjustment on the rear end shaft angle. It is what it is. The only thing to "adjust" is the tranny angle (with shims). However, the pinion shaft is sloping upward .7* while the tranny is sloping downward 1.5*. The driveshaft is sloping downward at .7*. So, my operating angles seem ok. #1 is .8* and #2 is 1.4*. Both are between .5* and 3* and the spread is within 1* of each other.
My concern is the the two shafts (pinion and tranny) are not parallel, nor can I make then parallel since IRS has no adjustment for tilt.
Anyone else have this issue? Will this cause a problem when I start driving? What can be done (if anything even needs to be done)?
So lets be clear. When you say "slope" do you mean front to rear? Meaning that when looking at them from the side the front of the tranny is up sloping downward and for the pinion the front is down and sloping upward, right? This being the case the difference totals 2.2 degrees and you do not have a problem. This is within the normal range and pretty much exactly what we strive to achieve for a live axle pinion angle where we have the ability to adjust it using the upper link. Here's a diagram I made about a dozen years illustrating it.
So lets be clear. When you say "slope" do you mean front to rear? Meaning that when looking at them from the side the front of the tranny is up sloping downward and for the pinion the front is down and sloping upward, right? This being the case the difference totals 2.2 degrees and you do not have a problem. This is within the normal range and pretty much exactly what we strive to achieve for a live axle pinion angle where we have the ability to adjust it using the upper link.
Jeff, thank you so much for chiming in. You are so much more experienced than me and your insight would help me a lot. Yes, they are about 2.2 degrees different. I get slightly different readings (within .1*) each time I measure, but I think that's just due to digital inclinometer rounding. Attached are some pictures to illustrate my questions / concerns.
1st is a pic of a "standard" from a website called "mastering driveline angles". They say the shafts should be within .5* of each other. I'm way off of that and can't find information to support the difference I'm seeing.
2nd is a pic of another website showing "good vs bad" angles for how the tranny to pinion shaft correlates to one another. They say my angles are susceptible to vibration since they are not parallel. My set up is equivalent of example #3.
3rd and 4th pics are of my measurements. These show a 2.5* difference, again due to minor variances I seem to get each time I measure. But, even with variances, they are never parallel.
My lack of experience leads me to be concerned about my setup because of what I'm reading. Any info you can share that can show me my concerns aren't valid would be appreciated. That way I can just "build on" without worrying that I'm not doing it well.
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She is constantly telling me when I encounter something difficult or puzzling, "You built a plane, this should be easy for you." Believe me, there were many things during the plane build that kicked my butt too!
Originally Posted by burchfieldb
