2Tc Build

[sharpshane]

Building a car for street and mild track use, what do you think?

 

I have this 2tc block that looks rebuilt but i can't tell, it's all cleaned up and the head too.

 

 

 

how can i tell what cam is in it?

what compression it is?

 

Now to make this cheap I will need your help. How much should I be able to pay for the items listed AND should I even consider these items?

 

Dual carby webers with manifold, online about $1400

 

Cam??? size???

 

Ignition set up?

 

Rebuild head with roller rockers? Is that too much??

 

I have a t50 5 speed trans. Do I need to rebuild it, is it easy, take it to aamco???

 

 

 

[altezzaclub]

The cam should have numbers/letter stamped on the back of it, which will refer to the manufacturer & the grind.

 

Otherwise you will have to draw a graph for both inlet & exhaust lobes using a dial guage and a protractor, so you plot lift against degrees of rotation and get a beautiful bell-shaped normal curve. Actually, i suppose you only need the lift at 50thou, max lift and when it opens & shuts a valve, as all those are published by the cam grinders.

 

The compression ratio means putting a piece of flat plastic over the chamber with a hole in it, sealed on with grease. (as are the valves) Then fill the chamber through the hole with turps from a burette or pipette. You should get a volume of 30-35ml, so you can easily work out the ratio between the chamber plus the head gasket (about 5ml) to the cylinder+chamber+gasket.

 

If you want to know how much to skim off to get a certain ratio, mark the edges of the chamber on graph paper, cut it out & count the squares to get the area. 9or weigh it against a known area of paper) Then you can calcuate the cylinder (area X skim depth) you will be milling off to increase the compression.

 

Google yourself stupid with the mathmatics of fluid flow then decide on what porting to do, matching all manifolds and carbs/extractors.

 

Aren't you glad you never bunked school on maths days!

 

Bits here in post #11-

 

http://www.rollaclub.com/board/topic/42407-the-girls-ke70/

 

Pop the sump off the block and look at one main bearing and one big-end. If they are new you will see, and if they look a bit worn you can use plasti-gauge to measure what gap they have. You should be able to see crisp clear hone marks in the cylindes if it has been honed for new rings.

 

I wouldn't bother with roller rockers yet. Get the flywheel lightened, get all parts balanced and get it running. You can decide between twin DCOEs or quads off a motorbike, it depends on how much room you have under the bonnet. You'll need extractors & a free-flow exhaust. Grab an electronic dizzy and have it re-curved to suit the motor once you have it running.

 

then put your money into the suspension & brakes! Hold those horrible leaf springs in place, get good spring and shock rates for weekend warrior work and fat sway bars.

 

then put money into a close ratio gearbox & LSD. (don't weld the diff..)

 

Take plenty of photos and post them up as you do it!

[GJM85]

My old man did one in a ke70. Went well indeed.

[tojo2]

2tc are hemis so will need a bit of measuring / calculating of piston displacement as well , for the compression ratio equation.

 

Might want to measure the stroke as well as some 2tc are moded with 3tc crank/rod/piston

Edited February 15, 2012 by tojo2

[sharpshane]

wow, i got some work to do! Thanks to all, ill post pics along the way

[sharpshane]

i found a dual side draft set up used for cheap, tips on the linkage would help with pics.

[altezzaclub]

That photo is too small to tell, but they should have a linkage in there.

 

The cable goes onto one outer end and between the carbs there is a U-shaped lever with a spring & a screw on one carb intersecting with a lever only on the other. The 2nd lever goes between the spring and the screw, which is how you set the throttles to match each other.

 

If they're not there I'n sure you can buy them from Redline or similar.

[sharpshane]

yep, not there, this one has been modified. I'm just trying to think on how to hook it up, the cable will have to pull from the bottom. I'll post more pics tomoroww. :hmm:

[sharpshane]

 

made the intake gasket and took off the old single weber

[altezzaclub]

I made up the linkages I needed, but there isn't much room between Webers as I remember, that's why the cable pivot goes on one end.

 

http://www.rollaclub.com/board/topic/42407-the-girls-ke70/

[sharpshane]

problems: the carbs are set up to pull down on the linkage, is there a way to flip these or some how a reverse cable set up?

inbetween the carbs i would push that linkage down towards the ground, it seems backwards, shouldn't it pull up?

 

 

 

this is the current set up complete with zip tie

Edited February 24, 2012 by sharpshane

[sharpshane]

k i found that the action is not reversed and I'm dumb...i just need to buy a kit that mounts to the webers

[altezzaclub]

Yes, you buy a triangle pivot that turns a push into a pull and mount it on the tappet cover. Most old cars had rods for the throttle instead of cables so they pushed.

 

This linkage marked in yellow between the carbs needs to be adjustable. The two screws in white set the idle for each carb, and when you're happy with that you then adjust the center link until they open together. The guy who did the conversion to cable may have ruined that.

[Miximus]

k i found that the action is not reversed and I'm dumb...i just need to buy a kit that mounts to the webers

 

Hey man, i just bought Twin Dellorto's for my 3TC, just wondering... how much clearance do you have between strut tower and carby's??

[sharpshane]

Its about 4-5 inches, it can difer depending on the horns and intake manifold though