3.0 SC High Performance Rebuid

[D911SC]

Originally Posted by Henry Schmidt

I can relate to everything you say, only with regards to a different subject:
I've been married 3 times and now dating a 24 year old and when I do dumb-ass stuff "I just have to remind myself why I'm doing this in the first place;
because I absolutely love it! "

This is one good reason why I never get tired of reading this thread!

[James Brown]

love to break that in!! And about break in methods, air cooled aircraft engines are run 45 min at max power climb then 30 min at 1/2 power, oil change and there good to go! Don't baby it the rings need to seat hard.

[lindy 911]

Something tells me she's WELL past broken in.

Lindy

[78SCRSMAN]

Hi,
I just ran across this and something struck me... anyway, just in case I overlooked something. You are using 95mm P's & C's with twin plug ignition?

[lindy 911]

That is correct. 95mm Mahle cylinders with JE 10.5 : 1 95mm pistons.

Lindy

[kenikh]

Great thread. What pulley wheel did you end up settling on?

[lindy 911]

I used the upper pulley half from Henry and still have the stock crank pulley. I'm going to change that to a Supertec also in the near future.

Lindy

[kenikh]

Originally Posted by lindy 911

I used the upper pulley half from Henry and still have the stock crank pulley. I'm going to change that to a Supertec also in the near future.

Lindy

Good to know - I'll have to ping Henry on acquiring those bits as well. Thanks!

[Rusty 356]

Okay, quick question: if you are going to limit the rpm to a speed below the power band for the cam, why put the DC80 cam?

[lindy 911]

I used a GE60 not GE80. It's chipped for 8,000 in the MSD box but I don't run it much past 7,200 or so for the time being. I'm still fine tuning the Webers and finding the right timing.

Lindy

[78SCRSMAN]

Just wondered where I can get a dizzy like yours... is it a modded stocker?
I've been looking at the different twin plug setups and was thinking of the Clewett one for the programability but if there is a less expensive way to go...

[cstreit]

+2 on running it hard for break-in. I beat the hell out of them (keeping it well under red-line). Found that if I don't rings don't tend to seat as well.

My typical break in is 20 minutes on the track under 6k RPM.

[lindy 911]

The distributor came from Aaron Burnham @ Rennwerks, 805-240-6931 It's a modified stock SC distributor that uses a Jag V-12 cap and custom rotor. Henry Schmidt @ Supertec has some stake in this as well. I looked at the Clewett crank fire ignition but I am running carbs and the electronic stuff does not afford a very big plug gap and they are susceptible to fouling the plugs, so I'm told. The twin plug distributor runs two MSD coils fired by an MSD 6-AL box. It's an awesome set-up.

Lindy

[kenikh]

The Burn Bros dizzy is about as far as you can go in terms of features and quality. It is a lovely device.

[Carrerax]

Originally Posted by kenikh

The Burn Bros dizzy is about as far as you can go in terms of features and quality. It is a lovely device.

What are your thoughts on the JB racing distributor? Mine should be here soon.

[RClewett]

From post 113 I looked at the Clewett crank fire ignition but I am running carbs and the electronic stuff does not afford a very big plug gap and they are susceptible to fouling the plugs, so I'm told.

You should be careful to who and what you listen to when people are telling you things.

When there is a problem fouling plugs, the underlying problem is too much fuel. With a carburetor, too much fuel is caused by incorrect jetting. If you mask the problem with a large spark plug gap, you still have carburetor that is not properly set up.

When a carburetor is set up properly, you will find more bottom and mid-range torque and there is no problem fouling spark plugs. Why would you want to mask more bottom and mid range torque?

Fix the real problem of too much fuel and the real benefits of the crank fire ignition can be realized. BTW, the correct mixture will also help a CD ignition.

Richard

[Jeff Alton]

Richard, good to see you posting on here! Your products and company are highly regarded!

I will be in contact again with you shorlty for a Tec3R.

Everything we have got from Richard and his advice has proven to be great!

Cheers

[lindy 911]

I did not mean to say that the crank fired ignition was no good, just not what I chose. Richard, you and I actually had a conversation and I was very close to using your stuff especially in light of the free plug wires you were offering just before the end of last year. That would have certainly been less money than what I had to spend to do what I did. The dizzy alone cost more that your entire set-up. Then, of course, I had to add the MSD, coils and plug wires.

As far as the plug fouling notion, you are right that the plugs should not have fouling problems if the induction system is set up properly. My problem was more about the type of plug I wanted to run and the gap it has. I'm using an NGK plug with twin grounds that don't let you set the "gap" in a traditional way. There is some adjust-ability, but not enough to get into the comfort zone (.035) your set-up seems to need.

My decision to use the dizzy arrangement was based on my specific choices and not the quality or performance of your product.

Lindy

[RClewett]

The systems I sell are only a couple of what is available. A gap of .035 is not unreasonable for a street car. The multi ground plugs are good for street engines and provide good exposure for the spark to ignite the charge.

One of the details that people often over look is the larger the spark plug gap, is the higher stress on all the ignition components. The larger the gap and/or higher the compression ratio, the higher the voltage requirement to light the plug. This considerably higher voltage breaks down ignition components. Spark plug wires or the resisters in the spark plug connectors being the weakest link in the system. For the daily driver, this means shorter intervals between service.

There is a point of diminishing returns on large spark plug gaps. For most engines, the HP difference between a spark plug gap .028 and .035 is 0. On a CD system, once the charge is lit, the spark plug is done. Where additional power happens is after the charge is lit, and combustion chamber dynamics and spark duration can play into the equation.

Richard

[lindy 911]

OK, I know this is the engine building forum but here's an update on the Grenade. I had Tru-Design build some 9" wheels for the rear and moved the 7's to the front. Also had the FB bits painted and installed them. Here's a couple of shots.

Lindy