More big block swap questions!

[Ed's 1970]

Hello guys,
My big block 540 is coming along. I have the bare block (bowtie gen 6) and most of the rotating assembly. Motor will be built this summer. I don't know at this time when it will go in, there are some issues with my car's suspension that have to be fixed before putting this beast in it. As it stands now, the car won't be able to handle it, if I put the motor in now, it would be pure insanity. What I really want to do is get the shell off the car and just redo the whole chassis and put the motor and other stuff in then. It's looking like the 540 I am building will put out 550-600 horse, and 650-700 tq, although it is capable of much more. I am just going to tell people it's a 454 , u can not tell the difference.

There are some other things I will need as you probably already know. One of them is an upgraded aluminum radiator. Are the radiator supports different on a small block car? Will I have to swap out the radiator support in order to install a big-block radiator?

The other question I had was the tranny. I think I need a rockcrusher, M22 or a heavy-duty 5 spd from tremec. Seems like the M22 would be much easier, although it only has 4 gears. Any suggestions?

The other parts of the drivetrain: I already bought some heavy-duty 3.0" half-shafts and chromoly strut rods. I plan on getting a heavy duty 3.0" driveshaft as well, the stocker looks weak to me!

The exhaust: I am thinking headers with stock routing to the back, but 3.0" polished stainless steel tubing with some 2 or 3 chamber flowmasters.

Thanks Ed

 

[Crimson Thunder]

You will have to change out the radiator core support(or just cut the hole bigger)so your new radiator can get some air.I'd go with the Tremec TKO 600 5 speed athough i think you can gat the T56 in a 600 ft version also.

 

[AKRAY4PLAY]

i would go with a Dewitt's aluminum radiator and electric fan kit. they are super sweet and truely a direct bolt-in replacement that will easily cool your motor. it will also give you lots more room up front to clear the big block. what tires are you planning on running?? traction, hard launches and big power = broken parts. if you are running regular street tires, might as well keep the stock rearend parts. if you go with slicks better start looking at heavy duty rear carrier, half shafts, spindles, u-joints and camber rods. also, what are you doing with the front suspension??

 

[Ed's 1970]

Thanks for that info Akray4play, sounds about right. I have heard of Dewitt's before. I wonder if the current radiator support has to be changed?

At this point, it looks like this is just going to be a street oriented machine, not street-strip, but u never know. I just purchased some big-block half shafts anyway, they are heavy-duty looking to me except the flange looks pretty much stock. You are exactly correct though, big power and big traction is broken parts...
That is why I have not raced my '94 Z28, it has a stock T56 which will not tolerate slicks for too long with 500+ horses.

Tires, probably stock rally rims. It would be nice to fit a 10-inch wide rally on the back, I noticed they sell those with a 5" BS! If not, 8-inch will suffice. If I go with cragars, it looks like I could fit a 17x9-inch wheel in the back with stock everything, just relocate the e-brake cable, no biggie. I am starting to like the stock wheel a lot better lately though.

Any suggestions on a wheel/tire setup would be a great help. I need new wheels and tires on this car soon.

The front suspension will probably be left stock with some new bushings and big-block springs and a bigger sway bar. I figure by then I will probably be broke...

 

[AKRAY4PLAY]

Ed,
have you looked at the Vette Brakes' performance plus suspension system?? it runs $2300-2400. it has everything to replace your suspension from the frame down. you can adjust the spring rate to suit your needs without buying new stuff. i have the kit on mine and love it. it is a whole new car. the big bonus is that the kit is totally bolt on and does not ruin or alter the car in any way. that way if you sell it to a collector, the conversion is easily reversible and will not hurt the collector value of the car. look into the kit, i think it will save lots of grief and money in the long run. i can gladly answer any questions you have about the system, just trying to keep the post semi-short.
as for wheels and tires, i run 255/60/15s on mine. i tried a buddies 17s with o-ring tires, it turned great but rode like a rock and would boil the tires at any thought of throttle compaired to my 15s. granted i'm running a 406 sb with 600hp and 590 ft/lbs, so tire fires are nothing new for me. i run the 15s with low air pressure to get a little "wrinkle wall effect" for launching and to smooth out the tar strips across the road. i set my suspension up a little stiff for cornering, but the low tire pressure gives a slight wash when first starting to turn. it is something that takes a little getting used to, but all in all she corners on rails.
you will not need a core support with the Dewitts radiator. it is litteraly a direct bolt in, just like factory replacement. the radiator and fan kit runs $900-1000 for everything you need for install. it is a very nice and clean set-up. you may want to get some new rubber holding bushings for it, Dewitts has them for a good price. also check all the Vette forums for group buys, you can save around 10% if you catch it right, same thing goes for the VB&P suspension kit.
well i better cut this off for now, give me shout if you need any more info or pics. sounds like your car will be sweet when done. later, Brian.

 

[Ed's 1970]

Brian, thanks for all those tips. Yes, I have looked at VB&P suspensions, they look like a good deal. I may go with that, we'll see.
I was afraid that the 17's would also hurt the ride. I love the ride now on the 15's, it is so much smoother than my '94 Z28, which has 17" centerlines and poly bushings, man that thing is like a board, it feels every bump in the road! So, looks like I will stick with the 15's and perhaps poly suspension bushings.
Looks like the motor is going to be the easy part in all this!

 

[AKRAY4PLAY]

the suspension is an easy install. you'll have more problems getting the motor spec'ed and installed. don't let that discourage you on the motor though! you can easily install the suspension in about 12 hours of getting after it with a good tool supply. i jacked around on mine while putting it in, measuring all the changes and such. it took me two days, case of beer and a couple bloody knuckles without air tools. i did everything on jackstands, a lift would make things a lot easier and faster, but it is still do-able. if you get a kit from VB&P, spend the extra and get the performance plus kit i think it is part number 42000. it comes with all new stuff from the frame down, including tie-rod ends and ball joints with all poly bushings.

 

[Ed's 1970]

What about the stock axles in the rear, are they going to hold up to 700+ ft/lbs of torque or do I need to upgrade to 31 spline axles? I don't plan to run slicks, just street tires.
Thanks Ed

 

[AKRAY4PLAY]

you should be fine with stock stuff in the rear end. if you go with drag radials or slicks, you'll want to upgrade to Tom's Differentials 12 bolt set-up with 1480 u-joint kit. the set-up runs about $4500-5000. street tires are the relief valve of the drivetrain. you will not be able to load them enough to twist stock stuff unless you are a complete tard with the clutch. dumping the clutch with a foot on the go pedal is always a bad idea unless things are made to take the beating. if you slip the clutch enough to load the drivetrain before getting on it, you'll be fine. http://www.tomsdifferentials.com/catalog.asp?pg=22 12 bolt carrier
http://www.tomsdifferentials.com/catalog.asp?pg=24 1480 halfshaft kit