Guest ebay240z Posted September 15, 2003 Share Posted September 15, 2003 I am finally getting ready to do engine frame replacement and subframe connectors for my 72 240z that will eventually have a JTR conversion to smallblock chevy. I have looked at all of the great information on Pete Paparaska's site and have looked thru previous posts on the subject and have come up with a list of questions that hopefully Pete or someone else that has done this mod could answer. I thought it would be good to post these questions so hopefully they could help others in the future. I plan on taking plenty of pics as I go along and also some video. I am good at turning wrenches but have not tackled a fabrication project this large before, so bear with me if these questions are a little stupid. 1. Is 2.5 x 2.5in. .093 wall square tubing still the recommended size? 2. Can I get by without narrowing the frame rails on the end, or will I have radiator clearance problems? 3. If I need to narrow the frame rails what is the best way to go about doing that? 4. Did you weld a plate on the end of the frame rails (firewall end) and then weld the frame rail to the firewall, or just weld the rail directly to the firewall? 5. Would you recommend welding the frame rail in place before welding on the T/C mount? 6. Would you recommend cutting out and replacing one frame rail at a time, or is there an advantage to cutting them both out and then replacing the frame rails? sorry for the long post, but I appreciate any info that can be supplied. Quote Link to comment Share on other sites More sharing options...
denny411 Posted September 15, 2003 Share Posted September 15, 2003 If you look in my personal gallery, I have a couple pics of my frame ties. I simply cut the existing frame rail and fit 3/16" wall 1.5"x2.5" tubing inside and welded completely around the ends and along both side. They are extended just past the firewall, and angle upward to meet the rear suspension. BTW... My design requires no floor modifications that can`t be performed with a hammer. Quote Link to comment Share on other sites More sharing options...
Guest ebay240z Posted September 21, 2003 Share Posted September 21, 2003 Very nice work Mr. Denny. I think the best route for me to go is the 'Paparaska style' frame rail since my right side engine frame rail is torn (the t/c mount is torn away from the frame rail). If anyone has gone the Paparaska way on there frame rails I would appreciate any helpful tips you may have. Quote Link to comment Share on other sites More sharing options...
pparaska Posted September 24, 2003 Share Posted September 24, 2003 Pete Paraska here. 1) The nice thing about the 2.5x2.5 engine rail is that it matches the old dimension nicely and makes it easy to just mock the OE rail. 0.093" wall is as thin as I would go. .125" thick would be fine - not that much weight difference. 2) If you go with the Griffin 19"Wx24"H radiator, you MAY not have to taper the engine rails in that area. 3) You could simply cut the wall out on that side, and part of the adjacent walls and weld the piece back using a "step" shape instead of my tapered shape. 4) I did close off the forward end of the frame rail, to keep water out. But not at the firewall - that got covered up by the gusset plates that connect it to the firewall, and "subframe connector" below it. 5) Yes, definitely! 6) One at a time. Measure several points on the OE frame rail and on the TC bucket, and the replacement, in all three up/down, for/aft, left/right directions. I used was a plumb bob, levels, carpenter's square, machinists sqaure, machinist's rule, string (for measuring left/right, for/aft, and diagonal distances), white tape on the floor, pen or marker, and took alot of notes and sketches with dimensions. Quote Link to comment Share on other sites More sharing options...
Guest Island Son Posted September 24, 2003 Share Posted September 24, 2003 Pete, On a car that has no rails left, do you think they could be built and then welded to the car and be made safe enough, i'm more woried about where arms that come back attach to the frame, getting them into the proper place. The rust is really bad, i have to fab xmembers and the rad mount at the front. Or do you think it's a lost cause? Sonny Quote Link to comment Share on other sites More sharing options...
Tim240z Posted September 24, 2003 Share Posted September 24, 2003 Sonny, That's gonna be a lot of work if the rad support is also rusted out. Read Pete's pages on 'mistakes' vis-a-vis the rust. I used 1 x 3 tubing on my frame rails and it worked out well. Pics on my pages. Tim Quote Link to comment Share on other sites More sharing options...
Guest Island Son Posted September 24, 2003 Share Posted September 24, 2003 Tim, I've read everything Pete has ever posted, the trouble is where i'm at there simply isn't any of these cars, i'm not so worried about the work, but the cost is a major factor, and if it would be safe enough... btw Tim, not many of your post slip by me either, i'm faily new to this kind of stuff and the info you gentleman supply is unbeleavable... My hats off to ya'll... Sonny Quote Link to comment Share on other sites More sharing options...
denny411 Posted September 24, 2003 Share Posted September 24, 2003 Sonny, you would be way ahead of the game if you buy a Z from one of the southern or southwestern states in the U.S and have it shipped to you. just figure how many hours of labor will be involved, not to mention $$$$. It`s almost a No Brainer IMO. I`m sure the guys here will help you scout out a deal on a very solid foundation for your hybrid project. Quote Link to comment Share on other sites More sharing options...
Guest Island Son Posted September 24, 2003 Share Posted September 24, 2003 Denny, I've thought about going that route a couple of times, i have access to a ramp truck and a nice drive down south would be awesome, but i'm a little concerned about bring the car back accross the border, i've seen a couple on here that really perked my interest, but when you consider the $ conversion and the cost to get it here it adds up pretty fast... I keep looking tho, at some point one will catch my eye that will get me started... I did notice that Pete mentioned not starting the motor untill the body was done, i'm wondering why, i have a couple of blocks ready just can't deside what to go with, and i figured i may as well get started on that and wait for the car as just sit here reading all day and dreaming and druling over some of the cars on here (i have ruined 3 keyboards)....lol Sonny Quote Link to comment Share on other sites More sharing options...
Tim240z Posted September 25, 2003 Share Posted September 25, 2003 As for the why..... Bodywork takes a LONG time!! Why tie all that $$$ up in an engine that you won't need for months, likely years. Plus, if you build an engine, by the time you get to installing it, you will have likely changed your mind on the build several times. Use the time working on the body to hunt for deals on engine parts and make your mind up on the type of build you want. I originally built my car for a carbed SBC. Bought all the accessories (trans, fuel pump, shifter..blah blah, blah), then found a really good deal on a LT1/T56. None of the stuff i had accumulated was any good to me anymore. just FFT. Tim Quote Link to comment Share on other sites More sharing options...
Guest Island Son Posted September 26, 2003 Share Posted September 26, 2003 That makes good sence Tim, i'm still way up in the air as to what to do, i've looked all over the maritimes and there is simply nothing here, there all in bad shape rust wise, and if i have to get into that i may as well fix the one i have as spend money on one that i have to do the same amount of work on... You have me at a disadvantage when it comes to the motor and tranny stuff tho i know little to nothing about that stuff, i've been reading till my eyes are ready to pop but that's still not going to help all that much... You may think i'm crazy but i want to do ALL of this myself, rebuild the motor and do all the fab and body work as well, the only thing i wouldn't touch is the tranny, and as i am typing this it will happen if it kills me.....lol I didn't even know these car were out there till i saw one in town, just plain jane and all stock, and to be honest not in very good shape but man what a sweet looking lil car, that was it for me, i'm hooked...lol Anyway it's late and i'm babbling, if you have any suggestion or whatever i'd be more than happy to hear them good or bad. Thx Sonny Quote Link to comment Share on other sites More sharing options...
Guest 350zgto Posted September 26, 2003 Share Posted September 26, 2003 I want to thank Pete and Tim for their help on this job, along with their many other contributions. I did the sub frame connectors from the firewall to the diff crossmember using 2" x 3" .083". My car had no rust at all, but the bottom of the factory sheetmetal "rails" were dented in, maybe from jacking the car up improperly, who knows. I used Petes great diagrams and then followed Tims example and cut some of the tubing to fit a new bottom for the engine compartment rails where they angle back from the t/c rod mount to the firewall. Quote Link to comment Share on other sites More sharing options...
pparaska Posted September 27, 2003 Share Posted September 27, 2003 Tim got my reason correct - you'll be changing your mind on the engine. Especially with the SBC. New stuff comes out all the time and a few years can make a difference in what you select due to new technology, designs, or even the wee-bit older stuff getting affordable enough for you to ebay it cheaply. That Z sounds like a basket case - even mine wasn't that bad, and I think I was nuts for rebuilding it! JMO, Quote Link to comment Share on other sites More sharing options...
Guest ebay240z Posted September 28, 2003 Share Posted September 28, 2003 Thanx Pete for answering my questions, your website has been a tremendous help for the planning stages of my frame rail replacement. Thanx for the input from others as well, this website is full of great information Quote Link to comment Share on other sites More sharing options...
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