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Chapter 20: 12/19/01 Drilling holes in carbs and more advance monkey business

12/19/01  Since last episode, I have been trying to get the engine to idle.  I set the static advance using a modern type timing light which works almost as well as a distributor curving machine.  I believe that the static is now about 15 degrees.  The vacuum setup has not been connected yet because the idle/vacuum situation needed to be ironed out.  The car would stumble and die if I didn’t continue to goose the throttle.  I couldn’t get it to run on fast idle either. Finally, I took the carb top off and set the floats closer to the top of the chamber.  I also had read that drilling out the idle jets 0.010” more than standard might help, but before doing this I wanted to check whether the accelerator pump was what was keeping things going.  I disconnected it, and the problem got worse.  A mechanic friend had suggested that drilling small holes in the primary butterflys might help.  This would put more air thru without opening up the transfer ports. Well, after seeing that the engine ran better with a bit more gas, I drilled out the idle jets with great improvement in idle and transition.  The drills I used were purchased at a hobby supply store and go down to very small sizes. Now that the idle is sorted out better, I can figure out what the vacuum/boost “curve” is from each of the ports on the carb.  One is manifold pressure and the other is the “ported” value.  Right now, the canister is set to retard the timing a bit too much under load, and I will need to revise my formula.

I routed gas temporarily around the mechanical pump, and it seems pretty happy this way, delivering 6 to 9 pounds all the time.  The A/F meter is reading in the  .8 and .9 volt region most of the time now, and the plugs look ok.   It’s getting cold here, and I need to get the heater motor hooked up next.

1/30/02  I’ve been getting another vehicle up and running, but have been thinking about the TurboStude.  In the meantime, it has been cold and slippery here, and not conducive with high speed or good traction…..  The heater, however, is working fine and the engine is settling in with a fairly low idle.  The thing is rich enough now on open throttle to make me a little less nervous, and one of the rattling sounds which I thought was suspicious for detonation has largely disappeared.  Now I can concentrate on the driveline a bit.  When I put my foot into it at almost any rpm, the engine runs away from the clutch.  Don’t smell any burning, but I must assume that either it is coated with an oily, caked residue like an old iron frying pan, or the lining is just plain gone.  The clutch springing never felt like much of anything from the beginning (now about 500 miles ago).  One way or another, I decided that I need something more substantial.  I found that though I can’t go to a bigger clutch in the stock setup, I can put in stronger springs on the pressure plate and add ceramic parts to the disk. 
  I was advised to get the flywheel face resurfaced at the same time.  These things can apparently be done by anyone who normally does clutches.  It will, however cost me $200.  If I were ready, I could have figured out a way to take an old Ford automatic tranny, change the input shaft and come up with something useable, but this seemed pretty straight-forward.  The clutch guys said that this would probably be ok to about 200-250 HP.
  I originally set out to double the HP of my engine, and now, with up to #15 boost, my calcs say that I am up at least to the HP above.  I used “Dragstrip Plus”  to try figuring out what might be going on.  It allows one to try changing various elements of the formula.  Though the assumptions on my camshaft are a bit off, it says that with proper gearing ,tire adhesion, and a cool engine, I already have a 13 second car!  Well, I don’t know if I believe that, but I have determined from the program that the optimal rear-end for this car in a quarter mile competition would be somewhere around 3.90 which would put me under 14 seconds at almost 100 mph.
The program was not shy pointing out that my valves were smallish (1.3″) and my lift was tiny (0.28″) and that my camming was skimpy.  Now, I’m not sure how well it understands what happens to breathing when a turbo is added, but it did ask specific questions about the turbo (but not ratios or anything that deep).  I’ll try the 3.40 rear-end in it, but found out that if I do want to change, the 8″ rear can be built up just like a 9″ with a limited slip pumpkin and a higher (numerically) gear.  The program actually told me NOT to go to anything as tall as a 4.56, though if I did, it would be a good 1/8th mile car.  It also showed me how significant the rear tire height can be in terms of ET and MPH.  Also surprising was what a positive effect running a cold engine could have. None the less,  Ted Harbit likes to warm them up and I’ll follow his prescription!  My buddy has convinced me that I’d better put on some good brakes up front before I kill myself, so I will be bolting on a disk brake conversion kit I had been saving for the 53′ Studillac.  Since the TurboStude has spindles from a 54′, it should be pretty straight-forward, though I may hold on the dual master cylinder conversion for the time being.  I guess I’ll spend the $800 at some point for the Turner conversion on the 53’……     http://www.turnerbrake.com/

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