Targa Truck '71 GMC build - The first truck in Targa Newfoundland.

[cmccuneusaf]

What spring rates are you running by chance?

[kingcrunch]

Hey Mark,

here's what i did to my trucks core support for weight savings:





The panels i cut out will be replicated in carbon fiber and glued/riveted back in place to have something to mount the headlight buckets to.
Around 9 pounds of weight saved in total. About half a pound of carbon fiber will be needed to hold the headlight buckets.


Your trucks core support is a bit more complicated but i think it could be done in a similar way.

[YAMATHUMP]

Thanks for taking the time to do this. Very cool truck and look forward to the updates.

[bovey]

More pics please. Love to watch this build.

Thank you. Working on it. So much happening and work is crazy.

What spring rates are you running by chance?

Well, it's a little tricky. My original spring rates were 1050/380. With the new set-up I was going to run 1050/550. But now that I have the No Limit Wide Ride IFS, this is all out the window. Will know more soon, or at least that is the plan.

Hey Mark,

here's what i did to my trucks core support for weight savings.

The panels i cut out will be replicated in carbon fiber and glued/riveted back in place to have something to mount the headlight buckets to.
Around 9 pounds of weight saved in total. About half a pound of carbon fiber will be needed to hold the headlight buckets.

Your trucks core support is a bit more complicated but i think it could be done in a similar way.

Very cool. I was thinking of a similar thing, I've also spoke to someone about making an aluminum version. Part of me so wants a stock appearing body. In the end my core support will only hold up body panels and the headlights. I want to get more fancy, but I want to drive it too. So, some things may be a little boring/heavy for this year. However, all bets are off until it hits some scales.

Thanks for taking the time to do this. Very cool truck and look forward to the updates.

Thank you back at you. Never expected anyone to care about a long bed GMC. More updates to come, lots more.

[bovey]

I assuming everyone here would like to see some photos of No Limit's Wide Ride IFS. The quality of this piece exceeded my expectations. The main crossmember is really nice, but please note Rob welded the rib in my main crossmember to add strength in my particular case. Normally, there are engine mounts AND and engine to add rigidity - Rob also wants me to add a cross bar and we'll extend some bars through the firewall to triangulate the front. Again, this is specific to my build, most others will have an engine sitting between the towers to add rigidity.



Tossed the parts on the scales. This combo is lighter than the stock parts. Sadly, I did not get to weight the stock crossmember before it went to scrap.
NOTE: I do have the lower A-arms and will scale them for fun.


A quick test fit. With a little pushing and pulling we got the chassis to be within 1/64th of an inch of square, which is better than anyone expected for a chassis built by GM in the early 70s, let alone after what I've put this chassis through.


I had ordered a bolt-in Wide Ride. After thinking about it, we decided that we should weld it all solid as I doubt it's going to live an easy life. Too my knowledge Rob sells a weld-in kit. Again, this was super easy to line up, it fit perfectly. So we went for it, two feet in.


Structural plates fit perfectly, the frame is now boxed between here and where the engine mounts are just behind the firewall.


Prepping for some paint and rough assembly. Note the double shear tab welded to the chassis. The front of the a-arm is double shear as well, it fits inside the hole you see in the cross member.


Too think, we had it all back together. And now it torn apart again. However, this is a game changer. No Limit's IFS solved a number of issues that became apparent as we moved forward.


As mentioned a couple of posts back, I did make a parts combo mistake. And it was my error, I knew better. We have the parts to correct the issue now. I'll get into it ONCE the problem is solved. No point in giving everyone mis-information.

[Ethereal]

Too think, we had it all back together. And now it torn apart again. However, this is a game changer. No Limit's IFS solved a number of issues that became apparent as we moved forward.

What issues did it solve, and are you still contemplating a complete custom chassis?

[kingcrunch]

I am waiting patiently for Rob to make stuff for Dodges...

[bovey]

I was a little tired last night when I wrote this. After reading it again, it needs some clarification. Notes are in italics.

So, a while back I made a mistake and it cost me a lot of time. A lot. Painful.

And by mistake, I should clarify it was a dumb one.

We had decided it was smarter to install No Limit's Wide Ride IFS. As outlined above, the parts are amazing and the installation was a breeze. BUT, in my brilliance I figured we could swap out the the No Limit spindles for the RSRT spindles I had. NOPE.

This was the end result, 8° of camber, nasty geometry and a near frame laying stance. The hoist is holding it up in this photo.


Let me state again, my fault, NOT RSRT or No Limits. Both were actually very helpful when it came time to solve this. However, I'm sure they will use me as a example of what not to do when speaking with future clients. I'm cool with that.

I wanted to use the RSRT spindles as it allows for the bearings I liked and the brake package fit these spindles.

The solution was easy, No Limit sent me a few extra bits that normally come with the Wide Ride.



From the outside. All good. This is not ride height. Better yet, this set-up has room for wider wheels and tires. Most likely 11" wheels with 305 or 315s.



Many, many thanks to Dr. G's awesome Fat Max build thread. He found these DRP bearing spacers for the Grand National floater from Speedway Engineering. I spoke with DRP and and ordered a set to build my 9" with.



FYI - these are Dr. G's photos. Pop over to his build thread and read about these. They are uber neat and solve a small issue I had with the 9" floater. DRP also does a treatment on the 2.5" timken bearing to make this combination have minimal roll resistance. Overkill for my build, but I wanted to replace the Chinese bearing that came with the floater.

These spacers allow you to set the preload on the bearings which helps longevity and helps minimize any form of pad knock back.



And finally. Another story of the great but also annoying things that happen when you take too long to get your project done. I had bought a complete Wilwood set-up for the truck and it would have been great. BUT then out of the blue a set of AP Racing calipers and rooters fell in my lap. Actually, a set of callipers 6 piston front/4 rear, 3 sets of rotors and hats AND 9 sets of pads. The parts are either new, slightly used, or rebuilt.

Had these arrived at any other point in the build, I may have passed. But we just figured out the suspension, and we have to make brackets to mate the Wilwood brakes to the front spindles and I need to design brackets to mate the parking brake on the 9" housing.

Further more, the general rule of thumb is buy the best brakes you can afford. In any other situation, I could not afford AP products. Nope. This is a right time, right place situation. I mention annoying because I could barely afford the Wilwood package, and now I own TWO brakes packages... sigh, I'm going to have a wicked garage sale this summer.



This stuff is bada$$. Actually it's bada$$$$$, but I got it for a great price.



So, yes. Way behind. However, I did buy my tickets and reserve a hotel for LS Fest in September.

The race is on.

I need to drive this thing this year.

[andrewb70]

Awesome. See you at LSFest, and Moscow Mules on me...

Andrew

[brawls43]

Finally got a picture from the inside of the car. Its not the best, and the glare from bugs on the windshield makes it a little worse. The lines are a little thicker then a normal cars rear window defroster, but once you get driving, you really see right past it like its not there.

[bovey]

Finally got a picture from the inside of the car. Its not the best, and the glare from bugs on the windshield makes it a little worse. The lines are a little thicker then a normal cars rear window defroster, but once you get driving, you really see right past it like its not there.

Thanks for this! So interesting, I think I'm going to stay with a blow motor set-up, so I can have somekind of air cirulation.

A quick update. The truck is mostly back together, brakes are done, clutch is done, etc. It just waiting for a spot of open up with my fab guys to move some bars around inside. Larger update to follow, life is a little extreme at the moment.

[Ron Sutton]

Looking like progress Mark. See you at the Workshop in Vegas, if I don't talk to you sooner.

[bovey]

When we last left off, the suspension was sorted, and I had a new set of brakes. However, the brakes needed brackets and everything to attach to the truck. For obvious reasons, AP Racing doesn't make a kit for a '71 GMC....

THANK goodness for machine shops.

Measurements were made, plans were drawn and milling machines and lathes where fired up. Material selection is important here, I figured we'd make this stuff out of 6061, but 6061 doesn't really like high heat. What you see below is 2024, it has better characteristics under heat, it keeps it's rigidity better during temperature change. It's also a little more costly than 6061, but not enough to warrant not using it. We annodized the parts once complete.




We had cut the caliper tabs off of the No Limit spindles. All of the bolt holes were existing so we used what was there.



Those bolts sticking out of the bracket we made. Titanium. Seriously. This was a nice surprise from the parts bin. These are Pratt and Miller bits, these have part numbers engraved in them. I'm going to get a price, just for fun. The important thing about these is how they work, the shoulder is key, it really helps distribute the load, thus helping minimize failure. They weight nothing... not that it matter on this tank of a truck.



This is the final result, the ring pushes the the rotor closer to the caliper mount and spindle. We were going to make the bracket wider originally, but worried about the leverage that extra 1/2" would put on the spindle. This was the simplist and cheapest way to make it strong. We could have made new rotor hats, but that would have been expensive. These hats are really high quality, sadly I can't recall the material spec.



All on. 378mm x 32mm (14.88" x 1.26") rotors with 6 Piston calipers up front.



In the rear, we made the brackets for both the rotors and the parking brake caliper. It worked out great. We did make one change to the Speedway 9" floater housing that you can't see. While building we had a concern about the bracket flexing as the rear brakes are bigger than planned, SO there is a little brace on the backside to eliminate the chance of flex. These rotors are 355mm x 32mm (14" x 1.26") with 4 piston calipers.



All the brake lines are in, including all of the flex lines. Opted to have the flex lines custom made by BMRS in California. It's a fairly simple process, measure a few times. Send them a list and roughly a week later a box of perfect brake lines arrive. You can see 3 of the lines coming out of the Tilton reservoir.

Why? I am fussy on brakes, this system has a lot of lines - more than I'm accustomed to using because of the Tilton pedal box and reservoir. This set-up is more common in race cars, so I went with BMRS as they specialize in this sort of stuff. The manufacturing process is similar to an OEM line, but high qaulity. It adds peice of mind when things get crazy.



Back on the ground, I must say I'm happy with the stance. Lower would be better, but due to where the engine sits, this it the lowest it can go. Wider wheels and tires are in the future.



The side profile makes me happy too. The wheel seems to be a little forward in the opening, but that might be due to the set-up not being finalized.



With it all together, we tossed it on the scales. Just to check progress. The truck is about 80% together. Complete driveline is in. The LED display showed promise. 3188 lbs with 50.02% front bias and 49.98% rear. It still needs some body panels, rad, exhaust, hoses, fluids, fuel cell and wiring, but for an all steel long bed with a heavy LSX iron race block, this is great progress from our starting point of 4068lbs with a 60/40 split.



Still working hard, more soon.

[andrewb70]

Mark,

This is turning out to be one hell of a truck!!!

Andrew

[bovey]

Mark, This is turning out to be one hell of a truck!!! Andrew

Thank you. I totally regret not doing a fully chassis at this point. But when I started this revision, this level of access to people, parts and knowledge was not expected.

Live and learn.

More to come and the new build partner I have might surprise you Andrew!

[andrewb70]

....

More to come and the new build partner I have might surprise you Andrew!

Tease...

[bovey]

Tease...

It's not 100% carved in stone yet. Need to make a few things happen first.

[SSLance]

Great update Mark!! Thanks as always for sharing.

[Dr G]

Great stuff. Love the brakes.

[andrewb70]

Just ran across this...

Andrew