Project Scope Creep - 67 GTO

[wayward]

Well I have been on this project about a year and have debated to or not to start a thread on the build.

This started off as a simple 2 speed Automatic to T-56 swap behind the original Pontiac engine.

I originally picked up a t-56 off ebay from a CTS-V. This unit does have the and I had it converted to a F-body by Jason at Texas DriveTrain Performance.

Well due to this website and finding a rotisserie at a great price all plans were off.

Here is where I am now...

67 Lemans convertible converted to a GTO
5.3L truck motor with LS-6 intake and throttle body
LS7 clutch
t-56
4 wheel Wilwood disk 12" 4 piston rear and 13" 6 piston front
Intro Wheels - Nitto 555 tires 245/45/17 front 315/35/17 rears
9" ford rear end with a Detroit locker.. - I picked up because I'm in nascar country and it was cheap... I will replace sometime in the future with the "right gear" yet to be determined and a truetrac

I'm going to do a fast forward over the project to date over several posts. I have been ask by some how I did something or what I wish I would have done. please ask anything, I'm no expert but have done several things again because I went the wrong direction first.

I mocked up the tranny and new motor to figure out what all would need to be done with the tunnel


my floor pans were in bad shape so I cut them out and started the replacement.



Put the new pans in and started making a tunnel. The tunnel is one thing I did several times before figuring it out.




More to follow...

[wayward]

I picked up a low milage T-56 off e-bay for $400 that had a cracked tail piece from an accident. Since I was going to have the tranny gone through and converted to a F-body.

for the price of the unit and since the CTSV does not have a slip yoke I will need to upgrade. But since I intend to have it completly gone through it looks to be a good plan.. fresh, new mains haft, seal, etc.. $1500 budget..



Sent the Unit to and from Texas from NC including freight and came in around my budget... Very Happy..

1. Replaced the mainshaft
2. Replaced the tail shaft housing
3. went through and do a overall refresh of bushings, bearings, etc...



Lesson Learned...

A CTSV bell housing is clocked different than a F body.

when i installed my modified transmission the crossmember was hitting the floor on the driver side and hanging about 2" below the frame on the passenger side. I looked all over the internet and spoke to several people. I couldn't get this confirmed so on the assumption of this being accurate the the CTSV bell housing being different I bough a quicktime for a f body.. Perfect fit..

[wayward]

I bought Doug's Headers for an A-body LS swap and the motor mounts. nice looking and good ceramic when looking them out of the box. But when installing them i am not impressed with the fit. They do not necessary hit the frame in the rear position but no way would they work in the forward position on the motor mounts. to measure the clearance between the frame and headers would have to be done with filler gauges and not a measuring tape.

Just a FYI...

I went ahead and notched my frame to allow for the adjustment and patched it back with 3/16 plate.

[wayward]

I'll go back an fill in more from the past year in the future but have had a good weekend so far. Working in a small garage and unboxing all this stuff make me think of Xmas with my kids.. - crap everywhere...




I should be back with a roller tomorrow...

[wayward]

Here is a quick update.

I hate to cover up things of this beauty

.

Got the car back to a roller to let me take the body off the rotisserie and put it back on the frame.



Slicked the firewall, replaced floor pans, painted the firewall and cut in the trunk with body color.

Used tinted raptor on the under side of the body and inside the trunk.



Not a great picture but there are 315s under there...

[AusMarty]

Those are 315's?
wow.
They look skinny!
GTO's are so wide. hahaha

[VinnieV67GTO]

Did you mini tub it your self or did you use a kit, like ABC?

[wayward]

I did it myself... I could not afford to spent that money for something I could do myself...

On the frame:
1. made gusset from the frame rail to the upper control arm bracket piece from 3/16" plate
2. I put on a 1 1/4 round tubing between the shock mount plates
3. I measured 1 3/4 from the inside of the frame rail and cut the frame.

4. I used 1 1/2 x 2 rectangular tubing and build an internal webbing and welded along the sides inside the frame and plug welded on the back side and the front side. - I'm going to have to find these pictures.. Thought I did them on my phone but don't see them.
5. i straightened and fitted the original side rails and reused for the holes and appearance. For strength I welded all side and plug welded to the internal structure I installed.. A lot of grinding but fairly easy. - if I were to do this again I would use some 3/16 here as well just for better appearance when painted.
6. i then reduced the frame rail from the front with about a 6" overlap over the "new" side plate.


on the body:
1. Split rear tubs
2. Added a 2.5" strip, I wanted to make sure I had enough room for anything in the future. currently a little more than 14.5" inside dimension

3. Finished fairly slick inside and out with grinding and some filler
4. Put body color raptor on entire bottom of car and in trunk area. ( had to replace left quarter, so I hope the raptor to reinforce the thinner quarter panel...

[bonecrrusher]

Where is that Food Lion at?

Kind of looks like one up in Concord.

Car is looking good so far!

[wayward]

That Food Lion is in Stanley up 27 NW of CLT. I live in a little down called Iron Station SW of Denver, NC.

Thanks, I was really trying to make it to LS fest but seems like everything is taking a little longer than I had hoped..

[VinnieV67GTO]

Looks good man thanks for the info. Do you think you could go up to the 335 like the ABC if you wanted

[bonecrrusher]

I drive through there on 73 all of the time.

My GF's folks live up in Morganton - and leaving from her house up in Huntersville - thats how we go up there.

I am in southwest Charlotte near Lake Wylie.

[wayward]

Looks good man thanks for the info. Do you think you could go up to the 335 like the ABC if you wanted

I believe I could.. My wheel wells are 14.6" and I'm about 1/4" less than that with the frame per side. I believe 335s are about 13.5" in general...

I did 315 because of the wheels i picked i was limited on max width as well price of tires. This was my car in high school and I'm really doing the car to just tool around with on weekends and burn up some vacation (car to take future vacations in). If I were serious about track days I would get bigger and softer tires (and a hardtop).

If you need any particular measurements let me know. I would be cautious to go to much more without mandatory coil-overs. The spring pockets on the inside part of the frame would protrude through to the outside. But if you had coil-overs you could box out both sides of the frame and be strong.

After saying that, if I were going to do 335 I would do:
Cross brace the frame Left to right and vertical (temporary), frame gussets, coil overs, narrow and box out the inside and outside of the frame and the same internal bracing I described above .

I believe most of the flex would be from the control arms forward but others here could provide much more actual road racing knowledge. I have built several chassis, a few have ran over 200mph in the quarter mile but have done nothing that requires turning, braking, and bumps...

[wayward]

I'm a few miles west of 16 and 73 on the left... I go through Morganton fairly often, I ride dirt bikes at brown mtn...

[AusMarty]

Even though the frame is separate to the body, reinforce the body mounts and possibly a partial cage or bracing against any torsional twist.
Just like a drag car for rigidity.

I'm sure there are people here who could provide better understanding.
But mine is - Stiffer car = more controllable, better handling car as all the flex will be moved to the suspension.

[VinnieV67GTO]

I plan on going to the coil-over set up. So that would not be to big of a deal. Thanks again for the info

[AusMarty]

As it is a seperate chassis, you might wanna look for some cross bracing?
And maybe a tailshaft loop setup?

That's give some serious midriff strength.
Bit extra weight, but it's also a good idea if the tail shaft decides to go on holidays.

[wayward]

I agree. I have built a massive crossmember for the transmission that bolts in firm and now the body is on will fab up a rear cross member that includes the drive shaft loop. I also added the standard tubular braces that runs between the upper and lower control arm bolts.

I know I cut a lot of frame out but I believe it is much stronger now with the plate gussets and the internal tubing of the frame that was welded internal and plug welded on the exterior sides of the frame..

I'm adding the cross members to stiffin up the length of the frame for general purpose...

Doing the coil overs, if you got your order of operation correct and didn't twist the frame would be very straight forward... To box inside and outside would be really easy because you wouldn't have to sculpt the interior bracing... To visualize the bracing like that on the side of a funny car frame... Vertical members and tubular bracing ran from the top of one vertical to the lower joint of the next vertical.. Just keep in mind triangles are very strong...

I don't know what I'm talking about as far as engineering but have stayed at a holiday inn express before...

EL

[wayward]

Looks good man thanks for the info. Do you think you could go up to the 335 like the ABC if you wanted

If I build another car more directed to performance I will do some research on something like this and cost of purchase vs. fab...

https://www.cachassisworks.com/popup.../78f313_1_.jpg
https://www.cachassisworks.com/p-155...ame-rails.aspx

This seems pricey but includes upper and lower control arms, double adjustable coil overs, sway bar, and back half of the frame..

I don't know what else is available out there, our conversation here just got me thinking..??..

EL

[VinnieV67GTO]

It might be a little pricey but I dont think it is too crazy if you wanted to go that route. I mean your getting the entire rear end set up with the 4 link setup.