68 F100 build, need solid advise

[Frank ZX]

I tore my 68 F100 down after attending the F100 nationals this year. I entered my truck in the show just for the fun of it. After everyone turning there nose up I decided it was time for a rebuild. I already have a Crown Victoria front end, 460 big block, and a TCI C6 transmission.
Originally I was just gonna swap to a rust free cab and new DOVE head and Comp Cam but after stripping the truck down to the frame, I did some research on autocross ing and Pro Touring. I already have 17X10.5 and 17X9 wheels and 315 and 275 tires. What I really want to do now is improve the rear suspension. I've researched till my head is spinning. I've got a basket full of parts in Ron Suttons Website. I really want to build a killer 3 link and watts link rear suspension. I've got room for roughly 36 inch trailing arms and 3rd link with some fab work.
Are 36 inch arms overkill or what?
This is a street truck driven on special occasions and events. I want seriously good handling and street manner. Help me decide which way to go. 128788

[Frank ZX]

I forgot to mention, I'm also boxing the chassis front to rear.

[Dr G]

You did not mention your budget. But if handling is your goal, then that big 460/C6 combo is not going to do you any favors, especially with a staggered (in width) tire and wheel setup. That is a recipe for understeer. I'd recommend 315's all around. And if you could afford it then some type of 351 based stroker engine, if big cubes are what you are after. Assuming it's in the budget.

Some knowledgeable folks on this forum recommend against fully boxing stock frames because it leads to cracking at the cross members. That being said the stock frames are very flexible and are not beneficial to performance handling.

I think a 3-link is a good choice on a truck as there is lot's of room for the third link. The longer links will reduce pinion angle change, so I don't really see a down side to it. Though I suppose there are diminishing returns at some point.

I'm sure others will chime in.

Gustave

[Restomod]

Well i will put in my .02..... Do what i wish i did and go full vic frame swap and dump the stock stuff. Put whatever engine / trans you want and rock it!

[Frank ZX]

Thanks for the replys!
315 all around is a great idea but that leaves me hunting for wheels or another rear end. The CV front is quite a bit wider up front.
The 460 has to stay for now because I already have everything to upgrade the powerplant. A new 5.0 is my dream but it's gotta wait.
I have thought about moving the engine aft even if it involves cutting the firewall and lowering the engine.
If I finish the frame boxing and weld x braces or triangulation thru out I hope to no induce cracks.
I copied Hacker's F100 hole punching.128828

- - - Updated - - -

Thought I'd post a few pics of the truck before teardown128829.128829
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I'll post more pics later.
Frank

[Frank ZX]

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This was at the F100 Nationals this year. As soon as I got home, I tore the whole truck down.

[Frank ZX]

[attach=config]128850[/attach

[Frank ZX]

I installed a new Comp Cam and kit but didn't like the specs so I've got a slightly larger cam and modified DOVE-C heads going in. I degreed the cam then tore it back down. I expect 500+HP at the crank.128856[ATTACH

[Frank ZX]

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[Frank ZX]

3 inch exhaust. That's probably getting redone too when I decided what rear suspension I'm going with.128860

[Josh@Ridetech]

Cool project, keep this updated for us!

[Restomod]

I think the stiffness of the CV chassis may be worth the difference of the front track width. I put just the cv front end and only boxed to the firewall, the stock chassis was made to flex. It in my opinion take a pretty stout boxing job to get the stocker to the same level.

[Frank ZX]

I think the stiffness of the CV chassis may be worth the difference of the front track width. I put just the cv front end and only boxed to the firewall, the stock chassis was made to flex. It in my opinion take a pretty stout boxing job to get the stocker to the same level.
Im gonna build the chassis as stout as my skill allows.
I'm adding several braces and taking out some of the stamped steel braces. Swapping to a CV frame takes some of the cool factor out IMO but each to their own.
I agree the stock frame was made to flex and the CV chassis was more rigid than the F100 chassis.
I'm waiting on leaf spring sliders and a watts link.
Thinking hard about adding a homemade torque link with some sort of a slider or pivot at the front of a torque link for axle arc. I have a couple ideas. Gonna stick with the leaf springs for now and I have too much in the big block and C6 already but have considered moving the engine aft a few inches. I'll post pics soon.

[Frank ZX]

I got a watts link kit and spring sliders. Also got the first crossmembers in place. Removed the stamped steel member and replaced it with square tubing. This is also gonna be the attach point for the watts link.
Slider instructions says to move the front spring eyelets inboard 1.5 to 3 inches inboard. Anyone don't this?
BTW, here some of the steel going in the chassis.129343
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[Restomod]

I understand creating more work than you have to, make your plan and do your best to stick to it.

[Frank ZX]

I understand creating more work than you have to, make your plan and do your best to stick to it.

So far I'm sticking to it.
I got the watts link bracket made and slotted. Tacked into place. My welders acting up so I couldn't weld except tack welds. I inquired about a set of Nascar truck arms so looks like I may use them. We'll see. Still have to finish boxing the frame in and fabbing crossmembers.129481
I'm not happy with the 1/4 inch link. I'm gonna make another side to the watts link for strength.

[48prerunner]

Looks cool I wish I had gone a different root that leafs in the back maybe on the next rebuild. hotrodstohell does stuff with truck arms maybe you could copy some of their ideas.

I think the crown vic frame would loose some of its strength without the body to tie it all together. The rear tank height kick up would require you to cut out most of the bed floor.

[Frank ZX]

Looks cool I wish I had gone a different root that leafs in the back maybe on the next rebuild. hotrodstohell does stuff with truck arms maybe you could copy some of their ideas.

I think the crown vic frame would loose some of its strength without the body to tie it all together. The rear tank height kick up would require you to cut out most of the bed floor.
The CV frame rear portion made me not want to swap chassis. Now I have to come up with a way to get strength out of the truck frame. Got the Nascar arms!

[MonzaRacer]

Hey research a leaf link set up. Basically you have a living point under spring then add in an upper adjustable arm directly above the spring. Mainly it allows setting any pinion angle and actually frees up axle. Also adding a stiffener above/on front of leaf spring with spring clamps for each leaf. And if you do it right you can " allow" a certain amount of spring wrap by tightening or loosening the spring clamps in front of axle. It also stiffens up leafs allowing removal of some leafs to tune rate. Because all your spring rate will be behind axle.

[projectPONY]

Hey Frank ZX, any updates?

[Frank ZX]

A lot of updates. I haven't posted the build but it's on the road. Not 100% complete but I've put 4K miles on it.
I went with a all aluminum 4.6 3v and TR360 5 speed. Balance is 53/47 front to rear! I used Nascar truck arms and coilovers all around. The chassis does pretty good but it needs some fine tuning.
The engine makes 332hp to the tires with just cams, exhaust and a custom tune. I had gauges built to monitor everything. I'm installing BMW 750 seats now. I removed 16 motors from them! Lol
Here's a few pics.144779

[Frank ZX]

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[Frank ZX]

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[Frank ZX]

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[Frank ZX]

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[Frank ZX]

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[Frank ZX]

I've had 2 surgeries on my rt elbow since I started this thread so that slowed me down a little. I'm dealing with Psoriasis arthritis now in my ankles so that again has slowed me down. This old truck keeps me active which is what I need more than anything.
I've drag raced it in a truck hard tire class and it did ok. No times were displayed so I have no idea on et or mph.
I have a nitrous system partly installed. It will be 100% automatic. Remote bottle opener, wot and window switch and bottle warmer on a thermostat.
I just did a cruise from Chattanooga to Somerset Kentucky. Some guy in a new Mustang GT kinda challenged me through some curvy sections of mountain roads and it did pretty good except the bench seat. We slid around alot. Lol
That's the reason for the lowbuck BMW seats.
I'll post more pics when I finish the seats.

[Josh@Ridetech]

Well, that's one heck of an update. You've been busy. The truck looks great!

The 3v's were a solid engine and you can really wake them up with some bolt on's.

Hopefully, the healing process on the elbow goes fast. Good luck!

[Jetfixr320]

Looks awesome! Great build.

[48prerunner]

looks cool any more info on your rear suspension? I'm thinking about ditching my rear leafs this winter, my biggest problem is wheel hop. I have similare set up to you except I have the coyote.

[Frank ZX]

looks cool any more info on your rear suspension? I'm thinking about ditching my rear leafs this winter, my biggest problem is wheel hop. I have similare set up to you except I have the coyote.
Have you thought about leaf spring sliders in place of the shackles? Maybe even clamping the fwd leafs together?
I have read several good books on suspension design. Wheel hop is fairly easy to fix. There's very little information on truck arms. I assume it's because their used in Nascar and no racers want to let their secrets out. Same goes for HTH truck arms. I come up with my own way of setting the arms up. I haven't autocrossed the truck yet but I have drag raced it and other than changing coilover springs, it will do both or atleast I think it will. I don't want to mislead anyone at this point or cause anyone to get hurt. I will tell you this much...make sure you have plenty of adjustment. If you ever see me out, your welcome to shimmy under the truck and see how I did it. I hope you understand where I'm coming from.
Im out of work because of this Aurthis. It went from my elbow to my ankles and it's hard to be on my feet any length of time. This truck keeps my mind off pain. Lol
Other than the gauge and switches, the nitrous system is completely hidden. The bottle is in a toolbox and the nozzles and solenoids are hidden under the airbox.
Turn the system on, open the bottle from the drivers seat and the rest is automatic. It shouldhave over 500hp to the rear tires with the AC on.145028

[Frank ZX]

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[lightningcow]

Are those some adjustable coilovers up front? What's the scoop on those?

[Frank ZX]

They are double adjustable Viking coilovers. I'm still learning and getting the feel for setting the suspension up.
I just put 700lb and 500 lb coilover springs on. The rear seems too stiff(maybe). Like I said, stI'll getting a feel for it. I would like to do a trackday or autocross with someone experienced in this stuff. Maybe I can hook up with someone that can help me...

[chevelletiger]

What yr 7series bmw did you get the seats from?

[Frank ZX]

I need to get on here more often. Plenty of updates. My 3v is now supercharged and wrecked the entire driveline with slicks. New motor, transmission, driveshaft and differential. I'll get better pics later.

[rustomatic]

Awesome truck--post more totally reasonable progress!