VinhZXT Posted August 29, 2006 Share Posted August 29, 2006 LS1 guys, My friend just bought a 2001 Camaro LS1 with the M6 trans. I will be ordering the JCI mounts for my friend since I don't want to fab up the mounts for him. I am wondering with the JCI mounts where does it put the motor? What I mean is the position of the center of the crankshaft compare to the center line of the 2 frame rails. I am asking this because I've made my own mounts before for my swap and I put the crankshaft where the original L6 crankshaft would be, in the horizontal plane. I couldn't fit the GM alternator on the driver side. If someone has the motor in the car can you measure the distant between the frame rails to the crankshaft for me? Thanks for the info. Vinh Quote Link to comment Share on other sites More sharing options...
Phantom Posted August 29, 2006 Share Posted August 29, 2006 Vinh, I'll try to get out to my car today. FWIW my engine sits slightly toward the passenger side, maybe 1/4" off center? My alternator sits low on the drivers side and the cooling port clears by only about 1/32". There are photos in my album of the front and top plus the clearance from the engine to the firewall. It places a T56 shifter about 1/2" forward of the stock position. Welded a tab on the front and a slight angle of the stock Z T-5 shift lever with the T56 bolt pattern in it and that brought the shifter up through the stock boot and into a very comfortable location for me to use. You may end up having to trim the alternator cooling port a bit as every car is just a little bit different. Bill Quote Link to comment Share on other sites More sharing options...
VinhZXT Posted August 29, 2006 Author Share Posted August 29, 2006 Hi Bill, Please measure from the center of the crank to the frame rails. Also what year is your car? Both of mine and my friend's Z are 77 models. The stock L6 crankshaft is about 3/4" offset to the passenger side, relative to the center line between the frame rails. I just looked at DaleMX photos and the motor looks like it shifted to the passenger side a lot. I ordered the JCI mounts already. I guess I will find out how good the mounts are and where the motor will be soon. Thank you. Vinh Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted August 29, 2006 Share Posted August 29, 2006 I am very interested in this info myself. I hope to set my motor in the next few days and have just begun to address the port and starboard placement. Quote Link to comment Share on other sites More sharing options...
Phantom Posted August 29, 2006 Share Posted August 29, 2006 OK - I've just been up to my elbows in black crap off my hoses. Here are the details. 1) It's a 1977 280Z - somebody has pleased someone! 2) From inside of frame rail to inside of frame rail it measures 25 1/4 inches. 3) From driver side inside of rail to the center of crankshaft pulley is 12 3/4" 4) From passenger side inside of rail to center of crankshaft pulley is 12 1/2". That means the engine is offset 1/8" to the passenger side from center as perfect center would be 12 5/8" from either rail. Quote Link to comment Share on other sites More sharing options...
VinhZXT Posted August 29, 2006 Author Share Posted August 29, 2006 Bill, Thanks for the measurements. I guess it is close enough to the original. It should be good enough. Quote Link to comment Share on other sites More sharing options...
Phantom Posted August 29, 2006 Share Posted August 29, 2006 Vinh, I was in your neck of the woods last week. I flew into Baltimore and then drove up I-83 to York. That's about 100 miles from Philly - right? Beautiful country - but then with 3-4" of rain every month - it ought to be! It's an interesting coincidence that I was in Milwaukee, Wisconsin about 3 weeks ago and went past the Harley-Davidson Headquarters and then was across the street from their main manufacturing plant in York last week. Hmm - wonder if there is something there? Anyway - hope the measurements give you what you need. I know my car has never been involved in an accident so they should be pretty accurate. Quote Link to comment Share on other sites More sharing options...
Lason Posted August 29, 2006 Share Posted August 29, 2006 3) From driver side inside of rail to the center of crankshaft pulley is 12 3/4"4) From passenger side inside of rail to center of crankshaft pulley is 12 1/2".. That would be 1/4" not 1/8" right? I measured mine and mine is 1/2" offset to the pass side using a plumb bob when I was settign my car up for the back half. I need to re-measure everything as Im about to get my 8.8" axle narrowed for the car. As far as the alternator I have to do some surgery on the plastic cooling cap on the back of it to clear the JCI mount but it wasnt bad. Im just worried about the main power lug on the back of it being so close to the mount. Ill just tape it all up after I install a wire on there. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted August 29, 2006 Share Posted August 29, 2006 Im just worried about the main power lug on the back of it being so close to the mount. Ill just tape it all up after I install a wire on there. I remember reading an old post where someone with an LS2 motor rotated the alternator in the mount to make the lug clear. Thanks phantom. Good info. Quote Link to comment Share on other sites More sharing options...
Phantom Posted August 29, 2006 Share Posted August 29, 2006 3) From driver side inside of rail to the center of crankshaft pulley is 12 3/4" 4) From passenger side inside of rail to center of crankshaft pulley is 12 1/2". That means the engine is offset 1/8" to the passenger side from center as perfect center would be 12 5/8" from either rail. Lason, No, the engine is offset 1/8" from the center of the car. You have to divide the difference by 2 to get the offset. Quote Link to comment Share on other sites More sharing options...
VinhZXT Posted August 30, 2006 Author Share Posted August 30, 2006 Bill, Thanks for the info again. York is about an hour and half from Philly. I only go out to York to the outlets for shopping. I remember why I had problem with my GM alternator. It couldn't fit on the lower driver side because #1 I used a C5 motor and the crank pulley is closer to the block compare to the Fbody motor. This caused the alternator to move back further and it ended up sitting on top of my lower steering joint. #2 because I have my motor sitting almost up against the firewall so that the header will clear my steering shaft. This also contribute to the alternator problem. My friend wants to get his swap done before the winter and I want to make sure I don't have to fab up anything for his car. The JCI mounts should be here sometime this week. Thanks again for the info. Vinh Quote Link to comment Share on other sites More sharing options...
Phantom Posted August 30, 2006 Share Posted August 30, 2006 Vinh, The key to the JCI parts is the engine mounts. They position the engine to allow all his other components to work properly. That way if you get stuck on something you can throw money at it and get a specific component from JCI. If you haven't already, spend some time looking at the photos in my album. They'll give you a pretty clear idea of how the engine mounts, which accessories work, etc. I don't have the same transmission mount as everone else. Mine is a modified torque tube design that locks the transmission tailshaft to the differential input snout. It is more complicated than a simple crossmember so John went the crossmember mount for his general offering. I know this is all pretty straight forward for someone with your experience - how refreshing is that - but give my a holler if you need any specifics on the JCI stuff that isn't in my album. Bill Quote Link to comment Share on other sites More sharing options...
Lason Posted August 30, 2006 Share Posted August 30, 2006 Yep i also have pics of the mounts themselves. I just pulled my LS1/Powerglide out last night to start fab of some subframe connectors and other misc crapola. Kinda nice, only took me 20 min from start to finish to get it out Of course I didnt have a shifter cable, tranny crossmember, driveshaft or anything else connected, lol. Just pull the motor mount bolts and lift her up and out. BTW, I also marked off the ground last night using a plumb bob before I yanked the motor and mine is 1/2" offset to the pass side. I wonder why the fluctuation with the offsets. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted August 30, 2006 Share Posted August 30, 2006 The mounting on the trans crossmember could easily twist the engine enough to cause the discrepancy. Quote Link to comment Share on other sites More sharing options...
Lason Posted August 30, 2006 Share Posted August 30, 2006 The mounting on the trans crossmember could easily twist the engine enough to cause the discrepancy. yeah I dont have a trans crossmember made yet so mine was sitting on a jack. I still need to make some subframe connectors to mount a crossmember to. I centered up the tranny and motor last night before pulling them out and took measurments then. The main reason I did it was so I can figure out my pinion offset for my 8.8" before sending it off to get narrowed. Quote Link to comment Share on other sites More sharing options...
VinhZXT Posted August 30, 2006 Author Share Posted August 30, 2006 Hi Bill, Thanks again for the info. Lason, The measurements of the crank to the frame rails depend on a big part of where the tail of your transmission will be. If you move the tail to the driver side then your offset will increase in the front. I've made some measurements of the tail end of the stock L6 relative to the frame rails also. When I put the LS1 in I did the same measurements and make sure the front and back measurements are close to the L6 measurement as possible. Quote Link to comment Share on other sites More sharing options...
Phantom Posted August 30, 2006 Share Posted August 30, 2006 Also, since my transmission is tied to my differential with a pair of 4" c-channel it's tailshaft location is set by the R200 location which, in my case is exactly where it was originally in the horizonal plane but about 1/2" higher in the vertical plane. Lason, Is your car a late model 280Z? Quote Link to comment Share on other sites More sharing options...
Lason Posted August 30, 2006 Share Posted August 30, 2006 Hi Bill' date='Thanks again for the info. Lason, The measurements of the crank to the frame rails depend on a big part of where the tail of your transmission will be. If you move the tail to the driver side then your offset will increase in the front. I've made some measurements of the tail end of the stock L6 relative to the frame rails also. When I put the LS1 in I did the same measurements and make sure the front and back measurements are close to the L6 measurement as possible.[/quote'] i realize that. I have my car up in the air on jackstands sitting level and have all kinds of points and lines marked on masking tape on the ground to refrence off of for my back half. I have two lines running down the middle of the car front to back. One if the center between the frame rails at the radiator support and at the rear measuring between the hatch opening with a line connecting the two. The other line is the center of my crank at the front and the center of my output shaft on my 'glide and a line connecting the two. They run paralel aprox 1/2" apart the whole way down. Ill double check everything when I get home but that is what I was doing last night before I pulled the motor and tranny. Also' date=' since my transmission is tied to my differential with a pair of 4" c-channel it's tailshaft location is set by the R200 location which, in my case is exactly where it was originally in the horizonal plane but about 1/2" higher in the vertical plane.Lason, Is your car a late model 280Z?[/quote'] Nope its a '73 240Z Quote Link to comment Share on other sites More sharing options...
Phantom Posted August 30, 2006 Share Posted August 30, 2006 Someone else dive in here but, if I remember right, the centerline for the R180 which the 240 Z was originally equipped is offset from the centerline of the R200. If you are using the R180 as your guide then the front of your motor will be swung in one direction or another from where it would be if using the R200. Quote Link to comment Share on other sites More sharing options...
Lason Posted August 30, 2006 Share Posted August 30, 2006 Phantom, im not using a stock rear end at all. Right now the floor is completley gone from the rear seat mount to the back of the car and all you see is ground. Im converting my car to straight axle and doing a mini tub with new frame rails. Im lining my motor up so its centerline runs with the centerline of the car. There is no offset of a R180,200 or anything. Im using a 8.8" Ford rear end out of a 94-up mustang. here is a pic of my car so you'll see what Im explaining. Excuse the mess, lol. Quote Link to comment Share on other sites More sharing options...
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