Make it handle

[Big Rick 53]

I LEFT out that my truck is a 66 c10 sub and that's why I want to mount everything as wide as I can all that roof up top = body roll in my thinking. The info on this site made me rethink my whole setup the only thing bothering me is who's wheels and tire will take a MONTANA chuck hole. That kinds of our autocross in the spring we have frost heaves and all the roads turn into a autocross with DEEP chuck holes instead of ORNAGE cones. Short side wall tire = broken wheel. That's why we have winter and road construction for seasons. WILL BE ORDERING A TRACK BAR and shock kit from NO LIMIT soon thanks to all this is best upto date info going.

[midnight340]

Rob, I have read this entire thread over the last week or so, taking notes all the way. I really appreciate your sharing your knowledge and love your trucks! (warning: non-Chevy content, but trailing arm related)

I need some help and have a couple of questions. I've run my truck for 20 years, street, drags, and autocross a few times... and want to improve handling.

First here is what I'm working on (a bit different from most here, but I trust the questions will be relevant to this forum):

1950 Ford F-1 w/ 340 Dodge/727 (so small block weight). Volare front suspension that I have ordered a Firm Feel 1-1/4" sway bar for, and plan to order Fatman dropped spindles. Am installing a Firm Feel stage two steering box and longer pitman. The truck weighs right at 3200 lbs (no driver) and is fairly light in the back end as I have no tailgate and am running an aluminum bed floor. Truck sits low, is chopped, with steel tilt front sheet metal. Rear end is Ford 9" with 3.89 gears.

The frame is boxed back to front cab mount, boxed over C-notch, has heavy cross-member about 16" behind cab. I will add the trailing arm cross-member (near rear cab mounts) and one for coil-over mounts. Frame has 7" rails.

I am changing from leafs to trailing arms. I have a Brothers aftermarket crossmember, stock trailing arms I've separated, painted and bolted together. I intend to run coil-overs at rear of arms outside the frame rails. Will run a fat Speedway Motors chromo 32" track arm at axle height or lower.

I am going to see if I can figure a way to reuse the stock Volare 1" sway bar on the rear with shortened ends to increase effectiveness (heat, flatten, re-drill ends)

Question 1: Since I failed to weigh the rear separately before tear down- do you have any suggestions as to where to start with spring rate?

Question 2: I have some budget limit, but am looking at 2" Pro TA shocks which are listed as compression 3, rebound 5, in Speedway Motors catalog. Would these be appropriate? and what length should I be looking for? Will 7" work (compressed 12.5", extended 19.5") I have about 4" axle to C-notch as it sits.

Any help you could offer (or anyone else!) would be appreciated. Or any other suggestions. Thanks, guys!

[midnight340]

Big Rick 53, I know what you mean about the chuck holes and road break up. I spent a year in Bozeman... a lot of high speed runs to Billings (no speed limit, in 1980 anyway). I think my ex still lives in Billings. Good times!!! Beautiful state.

[midnight340]

I forgot one question to do with anti-squat in the lengthy post above (sorry for the length, but didn't know how else to get to the questions...)

My truck has a 114" wheelbase, is light, and sits pretty low... so would it be best to mount the trailing arm with the bracket hole at the top vs lower position???

And thanks again, I appreciate all the info on this thread!!!

[midnight340]

Rob...Damn, I feel like a jerk! Just found where I needed to be on the No Limit Engineering site and found your fat track bar and see also you sell the Pro shocks. I'd love to order and support your business, only fair after all the great help you've been to so many!!
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[midnight340]

Some progress today, cleaned old brackets off 9" and clamped re-furbished arms to axle, located trailing arm crossmember. Checked centering, wheel location, x-measured everything. Will weld and bolt it up tomorrow.

(due to 1 1/4" offset of motor/trans I had to modify the crossmember a bit to give driveshaft plenty of clearance.)

I'd still like some advice on coil-over spring rate (mounted at end of arms behind axle and outside frame. Anyone with experience with this?

[robnolimit]

Looks good so far. for spring rate, think "light" Here's an estimate. 1400 lbs total rear weight. - 225 unsprung wt (axle, wheels/tires, 1/2 suspension, 1/2 drive shaft....) that nets you 1175 lbs sprung wt. , or appx 590lbs per side. If you use a coil-over with 5" of stroke, you have 2 1/2" of spring/shock compression at R.H. + 1/2" of static spring pre-load (never run the springs slack at full open) So think that you have 3" of spring compression at R.H. Now do the math, 590 lbs of sprung wt. divided by 3" of compression to R.H. = 197 lb/in or 200. Now, with the spring behind the axle, you gain on the motion ratio, making the spring feel stiffer. It has more leverage. You may want to drop to a 180 spring. With a 4" stroke shock, thats 2" to R.H., + 1/2" static compression, or 2 1/2" spring compression at R.H. so, 590lbs divided by 2 1/2" = 236lb/in. try a 225. good luck with the truck. R U going to Nashville Goodguys?

[hotrod1]

Hey ROB:

Automatic or Manual Transmission?

[68racer]

I used a 170 spring in that location with good results.

[midnight340]

68racer thanks for that input, I assume that's on a C10? or?

And Rob, I want to say I really appreciate the computations and the experience behind the knowledge.

On the installation on my F-1... in order to run low and to get good arm/frame clearance I had to pull the arms in a bit, putting the u-bolt partially below my c-notches which limits the travel I'd planned. I may modify the c-notch areas some... will have about 3-1/2" inches of travel (axle to frame) from ride height, but if I could run with only 2-1/2" spring compression I'd be fine.

So it sounds like I'd be fine with a 2" bodied (compr 3/ rebound 5) 7" shock (coil-over) with 2-1/2" 200-225# spring? Do I have this right?

And once I build the coil-over mounts (rectangular tubing across full width of frame) then I plan to x-brace from there forward to stock mid-crossmember. Should give me a good rigid rear section.

[AEA]

Something I've been wondering about. On a 67-72 C10 if you had plenty of horsepower and brakes. Would there ever be a situation where it would make sense to use ballast in the rear to help the front to rear weight balance?

[68racer]

Yes thats on a C10. I did the math with corner weights. The rear units are QA1, DD502 might be the part number. Sorry to be vague but I will have to check my facts.

[midnight340]

Rob, no I won't be making it to Nashville, but do hope to get the truck out some this year.

I see I typed in 7" in last post, but will be looking at ordering the 4" stroke/225# spring units. Am anxious to get the F-1 back on the street and see how it handles/rides.

At age 66 my progress isn't as fast as it used to be, but I do get into the shop more often so it all works out. As long as we are having fun, right? :-)

I did get my 1-1/4" sway bar... that's a fat bar compared to my stock 1" As far as the longer pitman arm, I've got a rear sump pan and may have to raise the engine some for clearance... but I'd like to get the 12:1 ratio vs stock 16:1.

[robnolimit]

Originally Posted by hotrod1

Hey ROB:

Automatic or Manual Transmission?

thats a tough call. For longer, full road coarse, i'd say manual. But for short auto-x, an automatic may have some merit. Trent Summers (Summers and Sons black '70 C10) and Mark Bowler (Bowler Transmission) worked up what may be the ultimat short coarse package. They built an auto - 4L80 I think, that does some very cool stuff. Using some electronics and delay box stuff, this is what it does.
1) it leaves the line on the converter like a normal automatic, then within about 2 seconds of the launch, the converter goes fully locked up, and stays that way, acting like a stick trans, and allowing engine braking and throttle steering in the corners.
2) buttons on the steering wheel control the up and down shifting 1,2,and 3, using a simple ail cylinder on a ratchet shifter. The up and down shift is WAY faster than you could ever shift a stick. Reverse manual valve body.
So, using an auto, they get off the line faster and smoother, and shift faster up and down. It is a bit heavier, and needs a big cooler.

That being said, I like a stick, but, I'm currently building a 65 mustang using a C4 with a gear venders OD behind it. I want to build this car capable of finishing the 'One lap of America' next year, and this combo lays out to be the simplest and most bullit proof. What? Never heard of the One lap? google it, it's awesome.

[hotrod1]

Thanks Rob.

[robnolimit]

Originally Posted by AEA

Something I've been wondering about. On a 67-72 C10 if you had plenty of horsepower and brakes. Would there ever be a situation where it would make sense to use ballast in the rear to help the front to rear weight balance?

Yes, I have ballasted plenty in the past. It's a trade off. Total wieght means slower acceleration, but balance can be faster in the corner. Also, rear weight can add traction. Solid steel blocks (I don't think I can say lead blocks) bolted to the frame rail, or a nice 3/16" steel tray to safegaurd the fuel tank. "No sir, thats not ballast, thats a skid plate to protect the fuel tank". "what, added strength to the rear of the chassis, no, thats a safety item"

[robnolimit]

Originally Posted by midnight340

Rob, no I won't be making it to Nashville, but do hope to get the truck out some this year.

I see I typed in 7" in last post, but will be looking at ordering the 4" stroke/225# spring units. Am anxious to get the F-1 back on the street and see how it handles/rides.

At age 66 my progress isn't as fast as it used to be, but I do get into the shop more often so it all works out. As long as we are having fun, right? :-)

I did get my 1-1/4" sway bar... that's a fat bar compared to my stock 1" As far as the longer pitman arm, I've got a rear sump pan and may have to raise the engine some for clearance... but I'd like to get the 12:1 ratio vs stock 16:1.

shock/spring sounds good. I talked with some guys this weekend atthe Hiedts muscle Car challenge, they're trying a Nascar inspired set up. 350 ft spring, REALLY progressive shock valving, and 1 7/8" sway bar. - mixed results. Just sayin, theres more than one way to skin a cat. Try Lee power Steering for the close ratio box.

[SCOTI]

Originally Posted by robnolimit

thats a tough call. For longer, full road coarse, i'd say manual. But for short auto-x, an automatic may have some merit. Trent Summers (Summers and Sons black '70 C10) and Mark Bowler (Bowler Transmission) worked up what may be the ultimat short coarse package. They built an auto - 4L80 I think, that does some very cool stuff. Using some electronics and delay box stuff, this is what it does.
1) it leaves the line on the converter like a normal automatic, then within about 2 seconds of the launch, the converter goes fully locked up, and stays that way, acting like a stick trans, and allowing engine braking and throttle steering in the corners.
2) buttons on the steering wheel control the up and down shifting 1,2,and 3, using a simple ail cylinder on a ratchet shifter. The up and down shift is WAY faster than you could ever shift a stick. Reverse manual valve body.
So, using an auto, they get off the line faster and smoother, and shift faster up and down. It is a bit heavier, and needs a big cooler.

That being said, I like a stick, but, I'm currently building a 65 mustang using a C4 with a gear venders OD behind it. I want to build this car capable of finishing the 'One lap of America' next year, and this combo lays out to be the simplest and most bullit proof. What? Never heard of the One lap? google it, it's awesome.

One Lap quality vehicles are the ultimate hot rods.

[midnight340]

I have my gas tank at the front the box (stock tank reversed out of the cab) and compete without a lot of fuel. Also I've run a spool for years now... Definite need for ballast so have an old implement gas tank cut in half behind tha rear end and always run a sandbag (high tech huh?). It has improved balance and handling immensely... Drags, street cornering, wet traction.
(Spools are treacherous in the wet with a light truck.... But you always have to drive according to what machine you're in.)
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[jc70chevy]

Hey rob should this help with some chassis flex.

[robnolimit]

yep, anytime you can shape in triangles is a plus

[1FUN64]

On my 64 I am wrapping up my NoLimit wide ride install and setting my engine back in the frame.

I am debating leaving my inner fender wells out.

1) To show offf the new suspension.

2) Weight savings.

Would the weight savings be offset by the stiffness the inner panels provide to the front of the truck? I do not have the frame boxed or reinforced (yet) maybe next winter.

My main focus is handling as I run in the local autocrosses as much as possible.

Great info in these forums guys.

[Baggerjohn]

On a 67 c-10 long bed daily driver, what is the best way to go for the best handling and great ride, static drop or air bags? Also, is there anything that can help to improve the turning radius? It's a tank. Thank you.

[bdiamond]

Originally Posted by Baggerjohn

On a 67 c-10 long bed daily driver, what is the best way to go for the best handling and great ride, static drop or air bags? Also, is there anything that can help to improve the turning radius? It's a tank. Thank you.

All those questions have been answered earlier in the thread. Its a long read but well worth it. I recommend reading it all at least once. You'll learn way more than you ever wanted to know

[skorpioskorpio]

Originally Posted by Baggerjohn

On a 67 c-10 long bed daily driver, what is the best way to go for the best handling and great ride, static drop or air bags? Also, is there anything that can help to improve the turning radius? It's a tank. Thank you.

Actually a tank can turn 180 degrees in it's own length, I get what you mean, but just saying.