CIS to EFI kit

[Europa Auto]

Nice work Dave!
I like the engine color combination. Have you dynod the 2.7 with the EFI?

[CindyDuck]

Looks like Tonys fan base is growing, as well it should. All the complements are true. There is also a thread about his venture in computer controled ignition, keep up the good work.
I will have new and accurate dyno numbers from my 3.0 after July 29th.
Mike

[zumwoll]

I am looking to get something that will deliver me more than the 12 MPG that my six webers does. My CIS is my three previous 911s managed 22 on the hwy. Of course this 74 is really pumped with JE Pistons, Garretson G60 cams and lotsa head work. WHat think. If I can get more mileage I do not mind giving up some of the blazing speed. It s costing me $50 to drive 200miles which is rediculous.

[Europa Auto]

It sounds like you are running too rich, try leaning your mixture and your MPG should go up. Tony at www.bitzracing can probably help you with this problem.

[CindyDuck]

Last time I calculated milage I got 22MPG from my 79 3.0. I am running as lean as I can, as it is my daily driver. I can do 35 MPH in 5th gear through town and excelerate to 55 on the highway without a shift. My buddy was with me and he admitted his CIS 3.0 could never do that, I dont know about a carbed car. On the 29th I will be on the Dyno to tune it to Max HP useing a wide band O2 sensor to get an AFR.
Zum, you could offset the cost of the kit by selling those carbs here in the classifieds, they are worth a couple bucks. I dont think speed would be compramised, you may gain some horsies along the way. The install of Tonys kit is easy if you have basic mechanical skills and the support is unsurpassed. I dont personaly know the guy but if you have questions he is always there. You would need a new intake, 3.2 works well. I and some others on this post have done it without breaking the bank.
If your thinking about it email Tony and he will take care of you.
Good luck and keep us posted.
Mike

[DohertyCM]

So If i get this kit does that mean I have to replace the MSD ignition box?

Also No one has posted a dyno chart showing before and after install.

How much HP gain do you get?

Last question..

I see the same size throttle body on all of the pictures...can you use a larger one? How about one twice the size.....
In theory can you use one of those HOLLEY four barrel jobs?

Just trying to get a feel for this mod before I buy it.

[tbitz]

Originally posted by zumwoll
I am looking to get something that will deliver me more than the 12 MPG that my six webers does. My CIS is my three previous 911s managed 22 on the hwy. Of course this 74 is really pumped with JE Pistons, Garretson G60 cams and lotsa head work. WHat think. If I can get more mileage I do not mind giving up some of the blazing speed. It s costing me $50 to drive 200miles which is rediculous.

Zumwoll,

EFI will get you much better MPG, that is for sure.

However converting to EFI will require CIS intake runners and airbox. I am not sure how compatible your cams will be with a plenum intake system. High overlap cams produce poor vacuum at idle making tuning more challenging at these low RPMs.

Folks that have converted cars with 964 and WEBCAMS 20/21 are very pleased with the EFI conversion, but I have no idea how well the G60 cams will work.

Cheers,

[tbitz]

Originally posted by DohertyCM
So If i get this kit does that mean I have to replace the MSD ignition box?

Also No one has posted a dyno chart showing before and after install.

How much HP gain do you get?

Last question..

I see the same size throttle body on all of the pictures...can you use a larger one? How about one twice the size.....
In theory can you use one of those HOLLEY four barrel jobs?

Just trying to get a feel for this mod before I buy it.

DohertyCM,

You still need to keep your MSD box. The conversion only controls fuel.

Post conversion dyno curve can be seen
here.

No need for larger throttle body. This is not the bottle neck in the 911 engine. Excessively large throttle bodies make for very poor part throttle control (Think ON-OFF and nothing in between).

Cheers,

[Scott R]

Well I just took the plunge, I'll post pics when I get done with the install. Thanks to everyone in this thread for the great pictures and information.

[Dave Taylor]

Scott,

You'll be very happy with Tony's EFI and his great support. Mine starts the first time everytime in all kinds of weather, hot or cold. More power and better mileage, too.

Keep us posted!

[Europa Auto]

Hey Scott,

Welcome to the EFI club!

We'll be here for you if you need any help!

[Scott R]

Originally posted by Europa Auto
Hey Scott,

Welcome to the EFI club!

We'll be here for you if you need any help!

I'm an IT consultant by day, so I should be able to at least get my laptop and the software up and running, but I'm sure to have questions on the install. Thanks everyone!

[Scott R]

Ok, for everyone that has completed their install, I would like some suggestions. First where exactly did you tap your vaccum line for the MS to? I drilled in near the brake booster line for mine.

Secondly, it looks like from some of the pictures, that people have elimnated the AAR and associated plumbing all together, how has that impacted cold start?

[Dave Taylor]

I drilled out a port in the side of my throttle body and tapped in there. Originally, I just teed into the vacuum line to the dist., but found out quickly that this was a no-no! Car ran like crap until Tony told me to move the line to the throttle body. Haven't had any problems since. I don't think I had the AAR on my '74. It's a great system and you're going to love it!

Check out this link to CIS To EFI conversion forum on Yahoo:
http://autos.groups.yahoo.com/group/bitzracing/

Might be another good place to post questions.

Dave

[Europa Auto]

Originally posted by Scott R
Ok, for everyone that has completed their install, I would like some suggestions. First where exactly did you tap your vaccum line for the MS to? I drilled in near the brake booster line for mine.

Secondly, it looks like from some of the pictures, that people have elimnated the AAR and associated plumbing all together, how has that impacted cold start?

Scott, I removed the AAR from my engine and it works great without it. The cold start is controlled by MegaSquirt.

[Scott R]

Thanks guys! I really want to get rid of as much of the CIS system as possible, and the AAR needs to go, pulling that will also eliminate the AAV, and the other pancake thingy on my 80'. I'm not getting as much vacuum as I possibly should, and I either have a intake leak somewhere, or possibly a dead cylinder. So I would like to eliminate as much as possible to assist in troubleshooting.

[tbitz]

Mike,

You sure you removed the AAR? Looking at the above picture I can still see it installed. Maybe your mixing it up with the AAV.

The AAR adds extra air when engine is cold to keep the engine from stalling. The little leaver beside the handbrakes can also be used to add air to the engine, but I am not sure all years have one.

The AAV isn't really needed and can be removed.

[tbitz]

As mentioned above, a Yahoo Group has been created where people can get together and discuss CIS to EFI installations with other people running the same conversions.

You can join the group here:
http://autos.groups.yahoo.com/group/bitzracing/

[Europa Auto]

Originally posted by tbitz
Mike,

You sure you removed the AAR? Looking at the above picture I can still see it installed. Maybe your mixing it up with the AAV.

The AAR adds extra air when engine is cold to keep the engine from stalling. The little leaver beside the handbrakes can also be used to add air to the engine, but I am not sure all years have one.

The AAV isn't really needed and can be removed.

Tony,
You are absolutely correct, I removed the AAV only. The AAR is still in place. I hope Scott is keeping track of all the postings today because he was planning to remove the AAR.
Sorry guys an honest mistake.

[Scott R]

This is the guy I'm talking about:




And of course he's the same loop as the AAV, I swear I can't see this guy in some of the install pictures. I doubt this unit has ever worked in my system, I have two and even when I had CIS I never had a warmup cycle.