Meanwhile, 4 years later............

[fred cook]

In 2013 I built a 3.3SS engine for my SC using CIS, Electromotive XDi, Mahle pistons and 964 cams. Compression is just under 11:1. Typical with projects, other things came up and the car only got driven occasionally. One thing that I could never seem to get just right was the timing, fuel injection adjustment and idle speed. The engine uses a twin plug system and runs quite well on 91-93 pump gas. Finally, this afternoon, I think I got the settings where they need to be! The XDi system has an infinitely adjustable timing system via 4 knobs on the controller. I decided to go back to basic P car timing settings and set the cranking timing to 5 degrees BTDC. The mid and upper range timing is set at 19 degrees which when added to the initial timing results in an advanced of 24 degrees. The 3rd setting allows for a timing reduction at higher rpms and I set that at -4 degrees. When running at high rpm, the total advance is now 20 degrees! A little CIS adjustment to lean the system slightly and a tweak on the idle bleed screw seems to have everything just right! It cranks easily, idles at 950 when warm and goes back to a strong idle when the throttle is lifted. Best of all, it really pulls well when running up thru the gears. My wife and I went to supper in it and she was amazed at how quick it can be! Now all that is left to do is to recharge the a/c and drive it like I stole it!

[emac]

Great work Fred---I'd love to have that in mine

Ernie

[Eli W]

Nice ride, love the no tail look on it.

Now drive it!

[Fabspeed Motorsport]

Beautiful - great work Fred!

Time to enjoy the fruits of your labor!

- Alec

[Luccia at Pelican Parts]

Beautiful. Looks like you take great care of her. We need more pictures!

[fred cook]

Originally Posted by Luccia at Pelican Parts

Beautiful. Looks like you take great care of her. We need more pictures!

Here are a couple more............ Car on lift getting an oil change and a shot of the underside of the engine, 4 years after rebuild but with no cleaning done! Both pictures taken today (Friday 24th). The engine is a 3.3SS with Carrera twin plug heads, Electromotive direct fire ignition, 964 cams, Mahle 100mm pistons, LN Engineering cylinders, large port CIS (with several mods) and SSI exhausts. Just a bit stronger than a 3.0 !

[KyMitch]

Fred,
It's been a while since I read your build thread, gonna have to dig it up soon!
I'm planning a build for my 83 3.0 based around the LN 100mm slip fits, twin plug, & upgrading to big port CIS as well..
Currently my old worn out stock long block runs pretty darn good thanks to sending my distributor off to Barry Hershon for a rebuild and recurve. MSD ignition of course. My timing is set very similar to yours actually. CIS loves that more aggressive curve!
As for the CIS, I stripped the entire Lambda system. I'm running nothing but an adjustable WUR. What mods did you make to your CIS?
My car pulls strong with great AFR's all the way to 7k until the factory rev limiter kicks in..
Why did you choose the Mahle pistons over the JE's? Aren't the JE's supposed to be matched up pretty well with the LN cylinders? I was considering their 10.5 CR option..
Anything you would have done different with yours?
Any tips would be greatly appreciated!

Thanks, Mitch Any plans on putting that beast on a dyno!!??

[fred cook]

Originally Posted by KyMitch

Fred,
It's been a while since I read your build thread, gonna have to dig it up soon!
I'm planning a build for my 83 3.0 based around the LN 100mm slip fits, twin plug, & upgrading to big port CIS as well..
Currently my old worn out stock long block runs pretty darn good thanks to sending my distributor off to Barry Hershon for a rebuild and recurve. MSD ignition of course. My timing is set very similar to yours actually. CIS loves that more aggressive curve!
As for the CIS, I stripped the entire Lambda system. I'm running nothing but an adjustable WUR. What mods did you make to your CIS?
My car pulls strong with great AFR's all the way to 7k until the factory rev limiter kicks in..
Why did you choose the Mahle pistons over the JE's? Aren't the JE's supposed to be matched up pretty well with the LN cylinders? I was considering their 10.5 CR option..
Anything you would have done different with yours?
Any tips would be greatly appreciated!

Thanks, Mitch Any plans on putting that beast on a dyno!!??

Mitch,

I used the Mahle 10.1:1 pistons because they were available at a good price from EBS. Someone had ordered them and then backed out. Once I had the pistons nailed down, I ordered the 100mm slip fit cylinders from LN. The Mahle pistons have a nice curved top shape, not a dome. The dome tends to block the flame travel while the Mahle shape does not. Of course with the XDi twin plug ignition that should not be a problem. After assembling the engine, it turned out that the actual compression ratio was just under 11:1! Each cylinder was measured at 160 psi compression.

I used a set of Carrera race prepped heads that came off a track engine. When I got the heads, I sent them off to Xtreme Cylinder Heads in Florida for a rebuild. They got new guides, new exhaust valves and a 3 angle valve job. They might not have needed the work, but I wanted them to last for a long time! The intake and exhaust ports had been cleaned up and polished. Even with the large port CIS runners, I still had to open up the cyl head end of the runners to match the ports. The runners are 39mm while the intake ports are 42mm. Did a similar thing on the exhausts. The exhaust ports on my heads are 41mm so I flared the ends of the SSI exhaust where they meet the heads to keep everything flowing nice and orderly.

If you use the Electromotive XDi system, the timing is completely adjustable. There are 4 knobs on the controller box to set the initial timing, secondary timing advance, high rpm advance retard and the ignition cutout point. If you have a/c since you are working with an SC 3.0, You will need to use the 3.2 XDi kit and a modified rear engine carrier. Otherwise, you can't make the a/c belt clear everything. When you mount the crankshaft position sensor and get it spaced properly, put a small metal hose clamp on it so that you can remove and replace the sensor without having to get a feeler gauge down in a place where you can't see and your hand won't fit!

For the CIS, I used the large port early SC airbox and runners. I used the other hardware from my 1980 SC airbox (fuel distributor, wur, aav, etc). I also replumbed it to resemble the 73.5 arrangement. Believe it or not, this franken-cis works really well. Starts easily, idles at 950 and pulls quite well all the way up to 7500 rpms. One other thing that I did was to add a spring loaded contact switch to activate the cold start valve. It only comes on at full throttle but gives each cylinder a bit more fuel while working hard. According to my a/f meter, it drops the a/f ratio from around 14:1 to about 13:1! Just a little touch to keep from burning a valve or piston. The airbox has a little aluminum distribution box mounted inside that makes the CSV fuel go into each cylinder. In normal driving, the CSV isn't activated.

One thing that I would recommend is to have the con rods rebuilt. In the rebuild process, have them shot peened to remove any latent stress risers that might be in the rods. Also, check weights on everything. rods, pistons, etc. I used a stock crankshaft with standard journals so standard bearings would work. Actually, all that I used from the original engine was the block, crankshaft, oil pump and flywheel. Everything else was new or a replacement.

Sorry to make this so long, but there was a lot of thought and work that went into my engine and I certainly don't mind sharing with anyone/everyone. Haven't put it on a dyno yet, but might do so in the near future!

[KyMitch]

Thanks Fred!
I appreciate you sharing these tips! Those heads sound pretty sweet. Not sure I'll get into any porting, maybe just some polishing on a set of Carrera heads as well. And some nice springs. I'm gonna see how much Barry will charge me to convert my dizzy to twin plug before I go crankfire since he just built it a year ago I've got the Large port airbox, runners, and air plate. I believe the throttle body was the same size thru all the SC years??
I'm planning on using a 964 cam grind unless I come across a more aggressive cut that works ok with CIS.
And I'm going to double check with the JE tops to make sure the CIS will be ok with them as well. I know the ideal piston for CIS is Max Moritz style and would like to go that direction if possible.
Still have plenty of homework left to do. I'd like to get the most out of this while still retaining the cheep and reliable CIS. Mitch

[fred cook]

Here are a couple of pictures of the Carrera heads and Mahle pistons that I used in my engine. The deck height wound up being 1.1mm without any spacers under the cylinder. Due to machining on the cylinder heads, actual compression wound up being about 10.8:1.

LN Engineering cylinder with Mahle 10.1:1 piston


Carrera cylinder head looking at the intake port


Carrera cylinder head looking at the exhaust port


Cylinder head combustion chamber

[Plays with cars]

Hey Fred, can you elaborate on why you chose -4 deg advance at the top end. Is it because of your higher compression and cam profiles? Is volumetric efficiency really high at high RPMs with your combination? Generally I thought that high compression was problematic at mid-RPM ranges, not on the top end. And, with dual plugs your motor shouldn't be as sensitive.

Curious because I am running a programmable ignition and am in the process of tuning. All done with the butt dyno at this point, so I'm looking to gain insight whenever I can.

[Joe Bob]

Nice work. No tail but still have front air dam. Be careful you may have some handling issues.

But have fun.

[fred cook]

Originally Posted by Plays with cars

Hey Fred, can you elaborate on why you chose -4 deg advance at the top end. Is it because of your higher compression and cam profiles? Is volumetric efficiency really high at high RPMs with your combination? Generally I thought that high compression was problematic at mid-RPM ranges, not on the top end. And, with dual plugs your motor shouldn't be as sensitive.

Curious because I am running a programmable ignition and am in the process of tuning. All done with the butt dyno at this point, so I'm looking to gain insight whenever I can.

The Electromotive XDi installation manual suggested a starting point of 10 degrees initial, 14 degrees secondary advance and -4 for high rpm running. I am still experimenting and at this point have the primary timing set at 5 degrees btdc, secondary at 19 degrees with the 3rd setting at -4. I think that I can reduce the second setting to 15 degrees for a total of 20 degrees advance btdc and set the retard at zero. Since each engine is different, there is no fixed/set rules for dialing in the timing. Once I get it where I think it is optimized, I will try to put it on a dyno for final tweaks. I took the car out for a 35-40mile drive this afternoon with some in traffic driving and some open road driving. Pretty pleased with the results and the couple of times I opened it up, the acceleration was pretty impressive!

[fred cook]

Originally Posted by Joe Bob

Nice work. No tail but still have front air dam. Be careful you may have some handling issues.

But have fun.

Originally, I had some oversteer issues with this car even with the 7x16 front and 8x16 rears. I changed out the 225-50x16 rear tires for a set of 245-45x16s which seems to have tamed the rear twitch. I have considered adding a duck tail but sorta like the smooth look. If I ever get to the point of doing DEs or track days, I might have to go ahead and make the change.