3.0 rebuild for performance advice

[icarp]

Sorry no pic posted

don't know
why

[icarp]

[icarp]

1980 911sc is car #704 , Civic type R is #703 , traffic light start
good fun
Ian

[KNIGHTRACE]

WOW that I plenty of information, I have used cams without any change to the CIS and it worked great especially on 9.8:1 Euro motors. However, I think the adjustable system is really inexpensive and worth doing. I built a euro 930/10 3 liter with these cams a few other small tricks, radian cut valves and 964 oil pump and made 237 @ the wheels. I sent a set to Michael D'Silva in Australia and he built a clients 3 liter there. He did not dyno it BUT he said it was the smoothest 911 motor he has ever driven. I will ask him to give his opinion. William Knight

[mikedsilva]

Originally Posted by groovydude

I'm trying to figure out the best bang for buck in an engine performance upgrade/modification. The engine is a small port (1982) 3.0 with 120K miles. It had a top end and new rings at 95K, it has the original head studs I believe. Currently have stock CIS, SSI headers and Classic Retrofit CDI upgrade. I'll be doing my own work.


It's the expected gains I'm trying to figure out of course. Any input will be appreciated. And if someone has thoughts for a different set of or additional mods, please speak up! Thanks.

hi Groovydude
(never thought I would say that to anyone!)

Yes, there are a plethora of things you can do to your motor. Where do you draw the line? I guess it comes down to where the car will be used primarily and of course your budget. If you are doing all the work yourself, well that saves a tonne of money.

I don't have as much experience as a lot of others on this forum, however I have built a few and driven different 3.0 cars over the last couple years...
The most recent engine I rebuilt started off completely stock apart from a set of SSi heat exchangers and a sports muffler. It only had the stock 8.5:1 compression pistons but it was quite torquey from down low (great for street) but ran out of puff around 5k.

Upon disassembly we found he had the 'big port' heads.. so we sourced a set of 9.8 used Mahle pistons and re-ringed.. at the same time, we chose to try the M1 cam that William Knight supplies. Pay careful attention to your deck height and your intake valve clearances as this is a much 'bigger' cam than stock (lots more duration).

No other mods were made. The CIS was left stock but treated to new gaskets.
The car runs a Dansk sport muffler but I am certain this muffler is slightly restrictive as while I was building this motor, I tried the Dansk on my own 3.0 car, and it definately felt slower at the top end... I think if the owner replaced his Dansk with something else he may see a benefit.

As William mentioned in the above post, this engine is the smoothest I have ever driven. It's almost freaky. Yes, I had the rods, pistons, pins etc, all balanced by the machine shop, but I've had that done with every other engine prior. This one is just so smooth. Is it the cam? I'm not experienced enough to say that it is, but that's the only thing different on this motor, compared to the others I have assembled.

It idles great, (little bit more exhaust note at idle) and is smooth and linear all the way past 6000... it almost feels like an electric motor it is just so smooth.

The owner loves it.. he only drives it on weekends through the hills and mountains but he keeps telling me how much more acceleration and how much harder it pulls everywhere. He doesn't seem to think we have lost anything down low, but it has not been dynoed (before OR after) so any perceptions of performance are purely that.

Again, we were very pleased with the result.

To give you a comparison, my own car is a 3.0.. I built it with 10.2 Carrillo pistons, ITBs, a full efi and ignition engine management system from Rasant, Headers, a GT3 muffler, bigger cams etc... and in all honesty, if my car had driven as well as the one above, I would not have spent all the money in efi. But that's just me.

[Bigtoe32067]

Or go all out
I have a 3.2ss with twin plugs, 10.5 pistons, I’m not sure which cam as I didn’t build it, large port worked over heads, and Weber 46’s. Made 295hp at the crank.

The intoxicating rush of this engine cause me to run it to its 7400 rpm redline for the first two shifts even though first is almost unless as its spinning the whole time and its even sideways into second.

I bought a set of Itbs from Al. but haven’t bought an ecu yet. This is in my future plans.
Funniest car I think I’ve ever owned and I’ve owned a lot of fun cars.

[KNIGHTRACE]

Mike D'Silva, Thank you for the input and help to the community. It has been a privilege to work with you and see you help the people in Australia, I am Thankful to call you a friend. It is a great feeling to see such enthusiasm in the community. William Knight

[boyt911sc]

Originally Posted by groovydude

I'm trying to figure out the best bang for buck in an engine performance upgrade/modification. The engine is a small port (1982) 3.0 with 120K miles. It had a top end and new rings at 95K, it has the original head studs I believe. Currently have stock CIS, SSI headers and Classic Retrofit CDI upgrade. I'll be doing my own work.

These seem to be my choices:

1. Don't open the engine, just add the following bolt on & tuning Cost ~ $500-$800. Expected gains = ???
- Set Cam timing to Euro
- Recurve the dizzy to Euro or replace with 123-ignition adjustable model.

2. Above PLUS new 10.5:1 CR pistons & cylinders. Clean up heads & keep single plug. Change head studs while I'm in there. Cost ~ $7200 Expected gains = ??? Also, do I need to replace the cylinders with these pistons, or can I run with the stock tubes?

3. Above plus more aggressive cam. Cost ~ $8200/ Expected gains = ???

It's the expected gains I'm trying to figure out of course. Any input will be appreciated. And if someone has thoughts for a different set of or additional mods, please speak up! Thanks.

Groovy,

Ian Carpenter came to visit me at home this morning with his green car with CIS engine. I have not met him until today and we talked mostly about CIS. We both share the same interest about CIS in general. And he invited me to get into his car for a short drive to show me his adjustable pressure regulator (WUR delete).

The adjustable pressure regulator is located between the two front seats with a round knob. And a complimentary AFR meter on the dash. So far everything looks normal and nothing out of the ordinary until he accelerated the car. You need to get into his car and experience yourself what this engine is capable of performing. I have been rebuilding stock CIS engines and never seen one like it.

I am a very skeptical person and not easy to convince. But my experience this morning riding in Ian’s car with a CIS motor is an eye opener. Anyone with CIS car wanting for a performance upgrade should consider this set-up. BTW, Ian lives in New Mexico and drove his car to the East Coast to visit his relatives. I just happened to reside nearby.

I will rebuild a motor using Ian Carpenter set-up. Thanks.

Tony

[icarp]

Tony , Thanks for the nice words . It was very nice to meet you . I am very impressed with your Lab for the work on the CIS parts , first class , data is everything when it comes to calibration.
I also enjoy your solve the problem attitude, and sense of humor . I am glad you enjoyed the performance from the 3.0 CIS engine in Kermit . The Key parts are the Cam , and the WUR delete .
With the adjustable regulator in the cockpit and the AFR meter on the dash it makes setting the mixture so easy. The Engine is a Small port 3.0 that is all stock with the exception of the M1 Cam and Regulator . More details on the 1st page . In the next months I will have a kit for sale
Thanks again Ian

[KNIGHTRACE]

The M1 cam seems to be the best we can put in a CIS 3.0. Great fuel economy, great power , also safer with todays fuels. THE WUR controller is really nice to be able to dial in the AFR's. William
KNIGHTRACE@MAC.COM

[Geronimo]

Knight, would the M1 be equally recommended for a 3LSC small port car running PMO's but still CIS pistons?

Either way the gains look amazing.

[James Brown]

Like most say, ignition is the best bang for your buck (mechanical advance to 36˚). Open up the intakes, CARBS, yes carbs (PMO's or Webbers) the rest of your parts will work well. Have fun.

[KNIGHTRACE]

Geronimo, They will definitely be the best you can put on a CIS piston for PMO's. The only down side to them is where you have to meet emissions. I would actually try these before you open the Intakes or anything like that. They work on stock springs and you don't have to tear a motor apart to change cams. I changed a set in my SC years ago without taking the motor out of the car. They will also eliminate many of the flat spots on carbs without having to over reduce the size of the Venturi's in the carbs verses a stock cam. This is because they stabilize the vaccum in the intake sooner in the RPM range. I wrote a small article on Carb Basics that if anyone emails me wanting it I will email them the article. These M1 cams were developed to maximize the HP and TQ on a motor with CIS pistons no matter what is on top of the motor. My email is KNIGHTRACE@MAC.COM. William

[Geronimo]

Nice, we have no emission test in MI. It's about the only thing I can do without opening a giant can of worms. The numbers you are making is impressive for a cam swap. If my motor checks out I might have to give these a try this spring.

[KNIGHTRACE]

I have quite a few sets in operation will very positive reviews. I would like Andrewcologne in Germany to give a set a try. It would be nice to get a set in Germany. Thanks, William
email KNIGHTRACE@MAC.COM

[jpnovak]

I have been using a cam grind that is basically 993SS intake/964 exaust/114LC. Clears the 9.8:1 CIS pistons and runs amazing up top.

Recent 80SC 3.0 build on the dyno yesterday with PMO EFI ITB/9.5"1/Cam described above/SSI/M&K. Made 180+ ft# from 3500 to 6500 and 213HP at the wheels.

[Geronimo]

213WHP isn't to bad for a 3L, what size PMO's. I have a 3L, 46mm PMO, SSI, M&K and would love more oomph. Knight's cam sounds like a great with without going full stupid on a costly build for small gains.

[KNIGHTRACE]

Good numbers, I built a 930/10 euro 3.0 last year made 229 HP at the wheels no other mods, can not remember TQ but have dyno in computer.

[Geronimo]

213WHP would mean roughly 250CHP, pretty respectable bump from the factory 180!

[Glenfield]

Euro 3.0 has a higher HP in stock. Closer to 204 post 1980 vs US cars of same years. Still a great bump though!