Too much torque?

[24OZ]

hi guys/gals

anyone used the Baddog frame rail strengthening kit?

i am looking at options to stiffen up the chassis on my 240Z,looked into a 1/2 cage but was told unless i go full cage it probably won't do what i want

car is a daily driver...or will be again soon :oops: so would prefer to keep things subtle and unobtrusive

what have you guys done to stiffen up the chassis and what have been the noticeable results

cheers

paul

[warrenz]

Hi

 

Do you have strut braces front and rear? They make a big difference I am told. I intend to install them when I get mine back on the road.There was a thread on here a while ago discussing this issue.

 

Warren

[Mr Camouflage]

Hi Paul

 

Getting the car double seam welded wouldn't hurt.

 

I think the best way to stiffen the chassis to handle lots of torque is to extend the frame rails to the rear sub frame, and maybe weld in a 2 sections out to the sills.

 

Cant find the photo I was looking for, but Phillip from Sweden has done pretty much the same thing with his car, though he has replaced the rails completely with steel tube.

 

 

More pics here: http://www.classiczcars.com/forums/showthread.php?t=17399&page=2

and here:

http://forums.voodoo-people.com/mull/viewforum.php?f=6

 

Strut braces help with handling, but I don't think they would help too much with the front to rear twisting force that the engine torque puts on the chassis.

 

How much HP you aiming for with the V8?

[24OZ]

thanks for the input guys

 

strut braces obtained and ready to go,may consider tying the front shock towers to the firewall in a triangulation,beleive this is worth doing for the minor inconvenience of welding a gusset bracket to the firewall

 

the swedes restoration is well beyond my capabilities or requirements for the Z's i have,sometimes i think it would be better to start with a basket case and do the full mods,my two 240's are too good to start chopping up,stripping to a bare shell or heavily modifying,rather i am looking at unobtrusive ways of assisting in structural integrity....not build a race car

 

luckily with the size rubber i can fit under the stock rear guards wheelspin will probably be the saving factor in preserving the body/chassis :roll:

 

so no-one in australia has used the Baddog rail kit i take it?

anyone used there own rail design?

cheers

paul

[PZG302]

Seam welding the chassis rails, inner guards and so on in the engine bay should stiffen the car up enough for you, however one word of advice stitch weld the seams only with welds about 50mm long with a 50mm gap between them.

 

This makes it easy to repair if the worst happens.

 

The seam welding works well. In my 240 I can jack up one corner at the front and both wheels will leave the ground.

[Zeddophile]

too much torque breaks gearbox mounts. trust me, I currently have a tiedown strap retaining my gearbox on one side until tomorrow...

[nat0_240_chevZ]

too much torque??? ha ha never, more the better

 

i find with my sbc 283, when stalling it up (when it had a knackered enginemount) would lift the left side of the motor easily up like a motor jack and only at about 1200rpm when then stally would start to grab.

 

i only have one of thos carbon endlink front braces but i dont thing it would do anything for chassis rigidity for a twisting force.

 

A traiangle brace from firewall to the crossmember mounts will do it but the tri brace from towers to firewall (as seen on hybridz) from my point of view does little unless tid to the lower rail near the crossmember, ie where the enging is conected to.

 

Baddog stylr rails do help a lil, by conecting to the rear, but its like having 2 pencils side by side and twisting them at one end, doesnt do much if you follow me.

 

The front cross member needs to be triangulated in a vertical plane across the strut towers, and then also tri'ed from that front tri to side tri's, this is exactly however what a roll/safety cage is.

 

seam welding is the easiest thing to do for yourself at this stage, but my car before i bought it had a 260z front clip put on after extensive damage to the rad support, and both rails, not only is the steel a grade thicker with lest rust due to the later model, but the guys (chassis blokes not sure who here in adelaide) sleeved a rect/square section inside the font rails and i find my car doesnt "feel" like it twists but how can you realy tell.

 

Yes i agree that any excess tourqe the car and tyres can handle ends up in copius amounts of heart pounding wheelspin. even bigger fatter wheels wont help much stopping this as its tyre grip that will reduce this, ie softer stickyer, not bigger, (but if bigger and stickyer then yes that will = more grip) Traction is measures like so "(grip/traction) = (co eff. of friction) X (weight acting on other surface)"

 

so its this coefficient that makes all the diff as youweight does not change, and this is irrespective on contact area, (well only slightly but almost and nearly neglectable, only testing shows small error).

 

Anyways, go for the seam welded front, the rails under the seats AKA as "SEAT SUPPORTS" wont give you much, although YES i will be connecting to the rear and have slip on over existing SEAT RAILS from 2-2.5mm folded section when i do. My reason is however for a overall chassis rigidness without the roll/safety cage.

 

hope i helped, Also 24Oz, your car looks remarkebly like mine, even the wheels look same/similar, provided it the pic as your avatar, ill post a pic soon.

 

nato

[24OZ]

thanks for that info,most guys on hybridz swear by the Baddog rails unless you are going to the trouble that Alsil went to

 

that pic is one of my 240's although i cannot take the credit for the build....i bought it like that...(i just put on the wheels,brakes and R200 lsd),.....much cheaper than building it yourself(like my RB30ET 240Z)go figure!

the current motor is a boss 302 but i have a turbo 302 that's itching to replace it.....just worried about twisting up the body with 500hp as it was a bare metal rebuild :lol: