awd92gsx Posted February 28, 2005 Share Posted February 28, 2005 This might be a better question for the driveline forum...but...it's about the V8 swap... OK, I finally got that sumbitch mounted...when I sit in the car, though, I notice that the tailshaft isn't pointing to the exact rear of the car and instead has a slight angle to it... Is this because the engine is offset to the passenger side some or do I need to redo everything? Quote Link to comment Share on other sites More sharing options...
A. G. Olphart Posted February 28, 2005 Share Posted February 28, 2005 A line drawn through the center of the output shaft should be parallel (both in the vertical and horizontal planes) with a line drawn through the center of the differential pinion shaft. In my car, I could get a fair idea of the sideways direction by putting a short (about 2 foot) aluminum carpenter's level against the tail shaft (as a long skinny square) and noting the direction it went; then I put it against the differential flange for a check. Just by eye, it looks like your tail shaft could be too far towards the driver's side. (You might have to slot your engine mounts a bit more to move it sideways). Quote Link to comment Share on other sites More sharing options...
Zoldman Posted February 28, 2005 Share Posted February 28, 2005 Bill, A.G. is right on here. If your mounts are slotted, you should be able to move the end of the tailshaft back to the passenger side (right) and get it parallel. You will still have some up/down angle between the trans and diff, but that is what u-joints are for, although you should shim and correct the trans height till you minimize the angle. Bill (also) Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 1, 2005 Author Share Posted March 1, 2005 OK... Well..poopie. I already drilled the holes for the rear mount crossmember so I'll probably have to slot/redrill them as well. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 1, 2005 Author Share Posted March 1, 2005 OK...I think I found my problem. For whatever reason, my transmission dipstick is hitting the passenger side of the transmission tunnel, getting caught inbetween the bellhousing and the tunnel. That is pushing the transmission to the driver's side and not allowing me to adjust the engine (even though I have plenty of room in my engine mount slots to play with). I just beat the holy living **** out of the tranny tunnel right there, so, hopefully, I've given it enough room to clear and allow for my adjustments. I'm going back outside now to put the engine back in the car... Man, I really hope this swap is worth all of this headache. Quote Link to comment Share on other sites More sharing options...
DavyZ Posted March 1, 2005 Share Posted March 1, 2005 ...Man, I really hope this swap is worth all of this headache.... Yes, it will be! Glad you found out a seemingly simple fix for the problem. I was going to say do not move the transmission crossmember, just adjust the mount, but it looks like you're ok now. Keep us posted. I think the first time you send the tires into smoldering molten torture, you'll realize the swap was totally worthwhile. Davy Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 1, 2005 Author Share Posted March 1, 2005 OK.... Pulled the engine 3 times since my last post. I'm kinda getting good at that. Anyway....here's what I found. Beat the tunnel and got the dipstick to clear, which helped...but, didn't perfect it. After making room for the dipstick I found that the tunnel was still hitting on a bolt sticking out of the side of the tranny...beat that in...helped a little bit more...but, still didn't make it... So, I finally found what may have been the real culprit. The transmission has some kind of ear sticking off of the side of it. I got tired of using the BFH...so, I got out my die grinder, chewed that sumbitch off (think...Mike Tyson)...and this is the result. I don't know if it's perfect, but, I can't see any angle to it with the naked eye looking straight over it. Quote Link to comment Share on other sites More sharing options...
Zoldman Posted March 1, 2005 Share Posted March 1, 2005 Me likee...... There's nothing that can't be fixed using the awesome power of the human intellect. Of course it helps to be really pissed off and have some large power tools..... Looks good; let us know when she's rollin'. Bill Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 1, 2005 Author Share Posted March 1, 2005 I could think of about 20 other things I'd have rather done tonight, but, I'm glad you guys talked me into fixing it correctly. One less thing I'll have to worry about when I actually get to drive the car again. Does it get easier from here? I hope so. Quote Link to comment Share on other sites More sharing options...
VRJoe Posted March 1, 2005 Share Posted March 1, 2005 I took a piece of pipe (plumbing tail stock, the kind you use from the sink to the trap) that had an ID the was close to the OD of the trans output shaft. I then slid a dowel into the pipe (had to sand it a little) so that I could slide it in and out some. I slid the pipe onto the output shaft, moved the dowel out and could then see how it lined up with the differential input shaft. Remember that there MUST be some angle between the two. Do a search and you'll find a bunch of posts about driveshaft angle. - Joe Quote Link to comment Share on other sites More sharing options...
Dan Juday Posted March 2, 2005 Share Posted March 2, 2005 Something else that gives you more room in the tunnel but has some differences of opinion here are the JTR spacer plates that fit between the crossmember and the frame rails. They do mess with your front roll center height but this can be corrected by relocating your lower control arm pivot points. More work, but it does give a surprizing amount of room for the tranny. I found this really helped when I was adjusting things to get my u-joint angles correct. It also lowers the whole motor and tranny for a lower CG and more hood clearance. More work, just what you wanted to hear, huh? Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 2, 2005 Author Share Posted March 2, 2005 Dan, I had actually already installed them. I didn't quite understand what they were for since the JTR manual actually makes *what appears to be* some errors regarding them. The JTR manual says they increase the distance between the engine and the lower crossmember, allowing more room for the harmonic balancer...however, since you are bolting the engine to the very crossmember that you are lowering it couldn't possibly effect the distance between the member and the harmonic balancer, unless I'm just not seeing something that they do. The only real benefit I see to using them is that it lowers the center of gravity a little more since it drops the engine down farther into the frame...However, I can see no apparant disadvantages to installing them... Somebody once told me that installing them would raise the car up a little, but, again, this is impossible since the height of the car is determined by the springs, not the front crossmember. Anyway...despite installing them I still ran into problems getting everything to line up correct. I don't know why I had troubles with things bumping into the transmission tunnel when a search pulled up nothing and nothing was mentioned in the JTR book. Cutting the tranny ear off seemed to make the biggest improvement and made life quite a bit easier!! Everything lined up much easier and went in much much smoother. With that being said, I think things will go a bit smoother from this point on. At least I don't have to worry about dropping an engine on my fender anymore Quote Link to comment Share on other sites More sharing options...
Dan Juday Posted March 2, 2005 Share Posted March 2, 2005 Your right Bill. I don't know what Mike was thinking when he said it gives more room for the harmonic balancer. Maybe too many beers that day? Seems odd to me now that you would be having so much interference even with the spacers. Forgive me if this sounds obvious. Are the JTR motor mount spacers on the correct sides? Do you have the correct motor mounts? Did you slot your towers and push the motor all the way forward (this position gives the most room for the tranny)? Please remind me what tranny you are using. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 2, 2005 Author Share Posted March 2, 2005 LOL, I thought about that, too...maybe I put the spacers on the wrong side But, no, I put them on the correct side. I'm using a TH350 (I know...but, it's only temporary until I can rebudget and get a 700r4 or a manual). I'm using a mount kit purchased from JTR and the mounts recommended in the JTR manual, however, the GM mounts JTR recommends were $50 each, but, I found them aftermarket for $8/each. I know JTR doesn't recommend aftermarket mounts due their stiffness, but, my car isn't exactly the most creature comfort thing on the planet as it is...Also, the recommended transmission mount is no longer available through GM, so I also purchased it aftermarket. The mounting bolts sit probably about...oh...an 1/8" more forward than where the original datsun mounting holes (before slotting) were with about 3/16" of an inch (or maybe less) left to push the engine forward. I had tried pushing the engine all the way forward, but, it wasn't helping at all. So, I'm not sure why I had the troubles. Maybe it's because I didn't do any transmission tunneling at all prior to dropping the engine in. If I was using a 5 speed I probably would have had no troubles at all. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 2, 2005 Author Share Posted March 2, 2005 Here's a pic of my engine...just for the hell of it. Quote Link to comment Share on other sites More sharing options...
Bartman Posted March 7, 2005 Share Posted March 7, 2005 After reading this thread I understand more about the spacer plates. If I'm understanding this correctly, what they really are doing is raising the chassis. The crossmember stays the same height and the chassis is raised one half inch above it. Because the engine is bolted to the front crossmember, the engine will sit lower in regards to the chassis. I didn't install these, and my question is do you think I need to? I think I would prefer not to have them, unless there is some compelling reason I don't know about. Hood clearance isn't an issue with my install and as Dan pointed out "They do mess with your front roll center height". Quote Link to comment Share on other sites More sharing options...
wheelman Posted March 7, 2005 Share Posted March 7, 2005 If I remember correctly the main reason those spacer plates were designed is to provide more hood clearance for a tall air-cleaner. Bartman, You're correct, they do lower the engine in relation to the chassis which actually puts the crossmember and engine closer to the ground. The car's ride height will not change because it's suspended on the springs which support the car from the strut towers not the crossmember. With an LT1 you don't need them and other than make more work to correct the roll center height and driveline angles they won't benefit you at all. AWD92GSX, Even with a 5-speed you still have to cut the Datsun tranny crossmember ears out of the tunnel and beat the tunnel for clutch fork clearance, at least I had to, although now I'm able to push my engine all the way back until the heads hit the firewall without causing intereference in the tranny tunnel. I'm not running it that far back though because I want to be able to get at the bell-housing bolts without pulling the engine and if I go to far back I don't like the position of the shifter. Wheelman Quote Link to comment Share on other sites More sharing options...
Psykovertible Posted March 8, 2005 Share Posted March 8, 2005 those spacers designed to provide a little hood/air filter clearance as well as firewall/bell housing. a little goes a long way for the fuel lines in the tunnel from ive been told Quote Link to comment Share on other sites More sharing options...
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