My Official GTM Build Thread!

[LCD Gauges]

Been a while...

Doors are kickin' my butt badly. I'm not happy with how they are opening; there's just not enough clearance to make it work. Furthermore,
trying to fine tune the gap spacing, and alignment is just a nightmare. For those that own the GTM, you will be able to relate during your
alignment challenges with the stock FFR hinges.

I've decided to hire a body man to come here and help with the C7 tail light mod (lens only), door alignment, and overall prep for priming.
After seeing Gene's video and some of the difficulties associated with creating a prefect base for paint, it is obvious that a professional is
required. I'm just not experienced enough to take on a project of this nature and expect a show-car, glass finish! I'm confident that the
person I chose will be able to sort out the known panel issues, and help me get this body ready for paint.

With that said, it's "game time decision" for the doors - now, or never to get the scissor hinges to work. I'm going to modify the hinges to
move the swing arm center to the right, and as high as possible which will be accomplished by adding material as shown by the red outline.
There is no other way (I can figure out) to get the door out, and over the pocket that is created by the fender and hood with the product
that I'm currently using.
new_door_hinge.JPG
On a brighter note, I'm working away on the electronics end. I've found a great processor that uses C programming code to develop a control
system to build some of the circuits featured in the OEM Corvette, as well as a few of my own. For instance, at the press of a button the
door could unlatch, turn on the parking & interior lights. Then turn off the parking lights when the door closes, and dim the interior lights
slowly after the engine is started.

Right now I've figured out the LED dimming (slow drain), and adjustable shift light. My next task will be using the processor to display outside
temp, IAT, Fuel pressure, and a custom message (such as showing, "GTM #105" during start-up) on an LCD screen. This processor also has
Bluetooth & WIFI capabilities to work with smart phone apps.
2014-03-16 13.35.44.jpg

Future project - "Twlight Sentinel" using a photo-diode array (mini solar panel) to trigger the dash lights when the ambient light level dips to
certain point. This sensor will be flush mounted to my gauge pod on the dash.
2014-03-16 13.34.42.jpg

Warmer temps rolling in now! I Hope all you northerners are getting some work done in the garage these days!

[LCD Gauges]

Updates on the engine as the EVAC system gets plumbed. The valve-
cover bulkheads, and fuel rails still need to be installed. That will pretty
much round out the motor mods for this year! It will be interesting to
see how much vacuum this setup will generate with straight-through mufflers.

To the Welding Guys:
I'm not too happy with the flux core method of welding. Either my technique
is bad, or flux core generally splatters all over the place. It's so bad that I
have to grind the splatter off! The pipes look terrible, so I'll have to wrap them.

Is there a way to reduce the amount of splatter? I've tried two different
heat settings (applicable to the steel gauge), a few wire speed settings,
and drag speed.

I have used a "spiral" back-and-forth motion to drag the 'puddle', and a zig-zag
across the joint in slow forward drag path. The bead looks best when pulling the
molten pool, rather than pushing it.

Perhaps MIG is the answer?

Weather continues to improve, so body work is on deck! That back end is starting
to look decent!
2014-04-07 15.07.22.jpg2014-04-11 17.41.23.jpg2014-04-11 17.42.01.jpg2014-04-11 17.42.37.jpg

[Edgeman]

I went with mig mix, the splatter got to me also. Then I purchased a tig, plasma cutter really like it.

[Fraser D]

Go with a gas shield on your wire feeder as it is the best bang for your buck.
You can also get some sprays etc that reduce splatter sticking to your work piece with varying results.
TIG is a very expensive option for a couple of welds but what you can do is tack the piece together then get someone to TIG it for you.
your options really depend on how much welding you intend to do during and post GTM build.

[LCD Gauges]

Thanks guys.

your options really depend on how much welding you intend to do during and post GTM build.

That is my dilemma.

Aside from the exhaust which is a show piece, I'm not certain that the expense is justified for any other welds on the car?
Everything else I've welded can be painted, or blended so the splatter never really bothered me.

I think I'll just wrap it for this year, and then redo the pipes at a later date - either with a TIG, or have someone weld
it as you suggested.

The gas shield with the Flux core wire seems like an interesting alternative. I'll look into that for future projects; it seems
pretty painless and inexpensive!

[VD2021]

You can try sacrificing some header wrap by wrapping the pipes prior to welding them.

Let the wrap take the splatter vise the nice pipes.....

[KeithBoden]

Get a gas conversion kit for the welder, and switch to small wire (.025 solid - no flux in the wire, as you are getting the shielding from the gas.) I used to be good with the flux core wire using a Lincoln 155 (220V) but when I started using shielding gas (25% Argon / 75% CO2 "steel mix") and the big spools of .025 solid wire, I was amazed at how nice the small machines weld! I still use the little machine on gas for lots of work even with a big TIG welder on hand. You just can't weld as fast with TIG; the little MIG machines will put a 1/4" weld in on max wire speed and top power range faster than you can keep your hands moving!

[LCD Gauges]

Vidal,

I tried using tape, and cardboard...but uhhh, I don't recommend that ( unless you like putting out small fires)

For the next attempt, I though about using tin from heater duct to cover the immediate area.

Keith,

I was under the impression that adding shielding gas required a higher voltage source, or current source. I'll have to check the
manual to be sure. If it's still able to run on 220V/30AMP then I'll be set!

Thank you all for the tips, and insight. The pipes are too far gone to save for this round, but I'll get it right next time. Live & Learn!

[KeithBoden]

I know the gas conversion for the Lincoln welders includes a few fittings, hoses, a solenoid, and a new torch shield. The solenoid doesn't take much power, and plugs into existing plugs inside the unit. I ran mine off 220v before and after, but to tell you the truth, I don't remember what breakers I have in the box for the welder extension cord. (I'm running a Lincoln Tig 225 off the same breakers.) I know my conversion job didn't mess with any other electronics or the 5-step power switch on the unit, so I believe the power output/input is unchanged. Of course the wire speed to match the power setting may change, but that may be more of a factor of the solid wire 'metal volume per speed' vs larger diameter cored wire. I switched to a smaller cable liner at the same time to go to .025 wire, which I like better than the larger wire sizes. On the top power setting, I use 9 out of 10 for the wire speed, which is roughly 8-10 inches of wire per second! That is another reason to rig a 10lb spool inside the unit instead of the 2lb ones - I'm on my 3rd of those.

[LCD Gauges]

Good info Keith. I wasn't able to locate the manual, but here's a photo of what I'm using. It's Chicago Electric #94164, Dual MIG welder.

94164.jpg
According to the graph in this PDF, this unit will draw up to 110 AMPS of current in voltage setting MAX2 which is required for some
mild steel when using solid core wire.

That seems a bit high?
http://www.manualslib.com/manual/655...page=17#manual
http://www.manualslib.com/manual/655...page=20#manual

Since I've already posted photos of my dirty motor in another thread, I'll pin them here as well. Excuse the mess,
but I'm trying to help someone figure out a problem with their fuel rails.

2014-04-14 21.16.52.jpg2014-04-14 21.17.21.jpg2014-04-14 21.17.48.jpg

[LCD Gauges]

The fuel rails are locked down, and sealed up. EVAC is roughed-in as the grommet,
and baffle still needs to be added on the left bank.
2014-04-16 21.30.26.jpg2014-04-16 21.32.24.jpg

A tiny tip to cover around 02 bungs: place one full wrap with a cut-out for
the bung, then start your spiral overlapping as you move along the pipe.
That gets rid of the exposed metal that you sometimes see!

2014-04-16 20.30.22.jpg

I'm not a fan of the wrap, but you can see why I decided to cover the pipe.
The scratches, and buff marks from removing the splatter just ruined the finish.
These pipes will be replaced one day...maybe a sexy Kooks system if the
Tooth Fairy is nice.

[LCD Gauges]

I can't do it...

The wrap is not sitting well with me. I'm tempted to redo (have someone TIG) the welds around the
flex couplers, and replace the section between the mufflers.

Before I go that route, I'd like to try polishing out the grind marks. Does anyone have
a recommendation for a polishing kit?

Thank you.

[Fugly_Old_Cowboy]

good old Dupont polishing compound worked for years but never tried it on stainless... when I was building boat props, after sanding smooth with progressively finer grits, I had a dual head grinder with cloth wheels & used black then red then green jewelers rouge to polish them up....

[KeithBoden]

I clean up welds with a 36 grit grinding wheel on an angle grinder because it is fast. When I am working on something that needs to look nice, I usually forget NOT to use the grinder for cleanup. It takes metal off fast, but also leaves really deep scratches. I have better results taking my time and using a die grinder with the 2" sanding discs. They aren't cheap, and you go through them fast, but it is easier not to put deep scratches into the work. You probably already know this, but if you already have deep scratches from grinding or using a coarse paper, you need to work your way up through the grits just like body work. I usually use 80 then 180, then 320 if necessary. I find that the worn out 180's leave a smooth enough surface to get a good spray paint finish.

If you want the welds to look nicer, one cheap option is to take them to someone with a TIG as they are now. Ask them to go over the weld and remelt it. When I do it, I make the same torch motions, and look for the same puddle characteristics as when TIG welding, but without adding filler, since the weld is already there. Using the pulse settings, you can even just move along at a constant speed, and let the high pulses make each successive puddle. I can make some pretty bad looking welds (in aluminum or steel) look like nice wide beads, and yours aren't anywhere in the ballpark of bad. If you want to go that route, don't grind all your welds flush, as they may burn through areas that ended up thinner.

[LCD Gauges]

...take them to someone with a TIG as they are now. Ask them to go over the weld and remelt it.

Very cool info, thanks! I'll see how things look after polishing tomorrow. After watching a few YouTube videos, I'm anticipating some shiny pipes & welds!

[LCD Gauges]

The polishing kit is going to make it all better. Right now I've done the first pass with an 80 grit polishing disc, and then used a rough cut
polishing wheel (right photo). I think I'll need to take it down one more step before polishing as you can still see lines.

2014-04-22 12.48.02.jpg2014-04-22 12.54.17.jpg

Found the perfect side marker from a newer Pontiac Grand Am. I'm going to try for the same bevel in the body as well.
2014-04-22 14.19.02.jpg

[LCD Gauges]

These polishing kits are fun! I've spent a good part of the night testing the compounds
on different parts of the engine: Cylinder heads, valve covers, roll cage, and aluminum
panels. I highly recommend getting a polishing kit, but be forewarned: Once you start,
you can't stop!

You can see the hack-job I did initially, followed by some restoration.

before_compare.jpgbefore_after.jpg



I fixed the grind marks, but now there are dark spots in the pits of the weld beads
that I'm not able to clean. That will get fixed once the welds get TIG'd up.
clean1.jpg

[LCD Gauges]

Played with the polishing kit some more today. This small bracket took about 30 minutes
to clean up, and there's even more shine to pull if you had all the time in the world!

Tomorrow I'm getting the exhaust TIG'd by a local welding shop. I'm anxious to see what
they can do for me.
2014-04-27 14.20.15.jpg2014-04-27 14.44.28.jpg2014-04-27-14.20.15.jpg

[carbon fiber]

Found the perfect side marker from a newer Pontiac Grand Am. I'm going to try for the same bevel in the body as well.
2014-04-22 14.19.02.jpg You can make a mold off the Pontiac panel where the side marker is (a little larger than the final cut size) and make a fg part out of the mold. Then, graft the fg part into the gtm body. The marker light and vent will fit it perfectly because it copies the factory opening. If you need any tips/info on the process, just pm me for contact info.

[LCD Gauges]

You can make a mold off the Pontiac panel where the side marker is (a little larger than the final cut size) and make a fg part out of the mold.

That may be difficult as I took that photo from a car in the parking lot at work. I'm going to assume that I'll have to remove the marker from the car to make
the mold?

Is there a method to make the mold using the vent, and marker light? Maybe prefab something in styrofoam, then 'glass over the contour?

[LCD Gauges]

A lot better than what I had done previously; $60 to reflow all the welds.
According to the man, it was difficult to reflow due to the flux-core wire
that was used. Something about too much flux present?

I’m not really sure what he meant, but he certainly put more heat into the
joints than my rig could achieve. We’ll see what a little grinding & polishing
can do for better presentation.

2014-04-29 16.16.36.jpg2014-04-29 16.16.11.jpg

[carbon fiber]

That may be difficult as I took that photo from a car in the parking lot at work. I'm going to assume that I'll have to remove the marker from the car to make
the mold?

Is there a method to make the mold using the vent, and marker light? Maybe prefab something in styrofoam, then 'glass over the contour?

Your best bet is to find salvage panels (L&R) to use to make the molds, then sell 'em after you're done. this may sound like a hassle, but it's not compared to re-creating the shape from scratch. you'll save hours of sanding, fitting, sanding, fitting, sanding, fitting, sanding, etc. They are a perfect fit to begin with. The marker light and vent would have to be removed and the panel would need to be prepped to make a mold from. (Waxing and PVA) Then gelcoat and fg. Like I said before, make the mold a little larger than the part you plan to make.

[LCD Gauges]

I'm sad, and happy to annouce that I sold the GTM to buy this 68SS. It was a tough decision, but...

I'm kidding!!!!!!!!!!!!!!!

This beauty is parked in my garage right now getting ready for a head/cam swap. Too nice not to share!
For those looking for an off-the-shelf cam that works well with stock LS1 short block, and cylinder heads,
check out the Thumpr series camshafts from Comp. The first stage Thumpr will work without any major
mods if you're using the factory 243 castings/springs, and rockers. Lots of duration, and a good deal of
overlap if you like the old school lumpy idle. The cam is great for street/strip, with a low to mid range
sweet spot. I'll get some before, and after video of the idle sound.

1904141_764284160262319_1707618556467988749_n.jpg


I've finally mounted the overflow canister, and found a new spot for the remote thermostat. I'll need to
fab a bracket to hold it nicely against the hatch mount.

Hey there's even some rust for me to clean, and maybe some aluminum to polish!
2014-05-01 21.40.16.jpg

I also had the pleasure of talking to Jason aka Carbon Fiber this week. I'm hoping to get something made for the centre console to jazz up the
focal point, and trim the stereo.

[LCD Gauges]

Some teaser pics of the bracket I made to secure the thermostat housing, and the rear tail lights/heat vents!

waterneck_trio.jpg

After many failed attempts, I've finally found a light that fits and looks very appealing. It's the FRS aftermarket LED lights from Spyder.
This is the look I'm going for. Time to order them up, and put that long winded chapter behind me.
Spyder_111-SFRS12-LBLED-BK_12.jpgF79179869.jpggtm_FRS_ink.jpg

[Shawn K]

Those look decent. What would you do for the reverse light? Mold in the same reverse light off of the FRS?

[LCD Gauges]

I was thinking in the diffuser area, or inside (behind) the heat vents.

[LCD Gauges]

Here's a template of Jason's (CarbonFiber's) console cover which will serve nicely to trim the stereo unit.
Contact him for details; I'll post updates as I get them!
carbonfiber.jpg

[LCD Gauges]

Happy May 24 weekend everyone! How do you like the 9 degree weather, and rain?

Just as well, I'll be swapping a swivel fitting on the x-over hose as it's leaking through the locking pin.
Luckily the tank can remain in place, but draining fuel is a messy task. There has to be a better way?

On a good note, I've been messing around with the micro-controller and programming. I was able to makeT
up some cables, and solder them down. There's still a bit of code to be written, and then I'll have to calibrate
the sensors to read the proper values on the LCD. This controller can handle about 50 inputs (analog, and digital),
so there's lots of room to play. Setting up security for engine start will be so much better now!
2014-05-16 05.07.59.jpg2014-05-16 05.28.28.jpgDSC_0204.JPGoat.jpg

[LCD Gauges]

It's June 1st in just a couple of days, and my plan was to have the car fully blocked, rear hatch bolted up, doors installed, and ready for a
test drive. No. The answer is No. It has been a slow process with a 5 month old in the mix, but I'm getting there!

Today the LED lights showed up, and they couldn't be sexier! The smoked lens is really going to set off the final look; it's just a matter
of fitting them into the lines of the back end. Hoping my "body guy" *cough* can work small miracles!

As you see in the photo, they are fairly big in comparison to the original tail lights. I'll have to modify the case of the lights, and re-work
the fiberglass more than expected. The C7 lights would have blended easier, but I wasn't willing to relocate the exhaust.

I'll see if I can get some pics/video of these things lit up!


2014-05-30 17.07.56.jpg2014-05-30 16.24.53.jpg

[Shawn K]

This is just a thought, but have you tried turning them upside down and putting them on the opposite side?

[LCD Gauges]

Hey Shawn, someone on the other forum PM'd me with the same thought. I'm not sure that will work because the outside of the lens has a reflector and lamp.

I'd like that to wrap around the side to act as a side marker if possible. The assembly is not flat, although it appears that way in the photo. It will take some
creative cuts to make them sit properly, and make them feel at home on the GTM.

[VD2021]

Can you post a side view pic of the housing?

[Fraser D]

My first though was to turn them upside down as well.
Just because the back of the GTM is basically flat there is no reason why you can’t section the top and side seam to match the lens profile. I agree, a side and top view will be helpful.
They look like very nice lights.

[LCD Gauges]

Here are some quick shots, and measurements. I didn't realize there was an additional lamp on the lower contour
that resembles a "neon tube". Very pleased with that; these LED's are slightly different than the photos I posted above.


red brake, amber turn, red DRL/night running
2014-05-31 16.25.33.jpg2014-05-31 16.26.35.jpg2014-05-31 16.28.33.jpg


13 inches long (lens only) , 5 inches on side , 18 inches overall length (including flared plastic)

2014-05-31 16.32.27.jpg2014-05-31 16.31.18.jpg
5 inches deep x 7 tall (at thickest point)
2014-05-31 16.31.55.jpg

7 inches x 13 inches lens area (at widest & longest points)
2014-05-31 16.31.35.jpg

Some of the plastic trim can definitely be removed if necessary.

[VD2021]

I remember now. The tail lamp on the scion frs is somewhat surface mounted and bubbled.

[LCD Gauges]

I'm liking the flip more, and more! I see how the round part of the lens compliments the shape of the body contour on the left side image.

gtm_FRS_ink2.jpg

[RumRunner]

+1 for the flip. Definitely flows better IMHO.

-Michael

[Fraser D]

I liked the flipped orientation better as well.
Question is, how does the unit profile blend into either the existing body profile or a modified one.

[VD2021]

I like the look with them flipped and swapped. Looks like they belong, working with the body visual rear profile.

I'd start by making a fg pocket for them (like I did with my side makers).

Put that(w/ the lamp) where you want it and start working the rear from there.

If it turns out like the photoshop image, it will be a great tail lamp mod.

[Shawn K]

They look much better flipped!