Cams for 3.2?

[movin]

Are C2 cams better than stock for a 3.2? are they a hydraulic grind? will they work if they are meant for hydraulic lifters?

[WydRyd]

I'm told the 964 CAMs are a "nice" bolt-in replacement for the stock 3.2 CAMs.

[Early_S_Man]

C2/C4/964 engines didn't have the hydraulic lifters! They didn't arrive until the 993 ...

Web-Cam 20/21 grind is even better than the 964 grind!

[TimT]

20/21 we saw 311 rwhp at the dyno on a 3.2, with siome other mods naturally

[marcesq]

Tim:

Can you share the other mods??

Porshin has just broken in the 20/21 cams, and has nothing but kudos for the set up.

[TimT]

Tec-2 engine management, TWM individual throttle bodies, appropriate crank and case mods to support high RMP longevity. Porting and smoothing of the heads. GT-3 oil pump. lightened flywheel etc....

[speeder]

Or anyone else who knows, I know that 20/21s are the most aggressive cam that CIS will work with, same for motronic? Will carrera engine management system tolerate bigger cams? TIA.

[marcesq]

Denis:

I believe that the 20/21 grind is the most radical cam that can be used without modification to the pistons of a 3.2 to avoid valve/piston contact. I am not certain as to whether the Motronic can tolerate more lift/duration if pistons are cut.

The CIS can not tolerate any greater overlap than the 964 cams, and even if it could the pistons would have to modified as well.

I am sure that Rob (Porshin) would be happy to share his experience in this regard. He just rebuild the top end of his 3.2 and really know his stuff.

[jhugh]

I have 964 cams in my 3.2L. Big, BIG difference. Definitely faster than stock. They are the chief reason, I believe, why I was once able to out-drag a new Camaro SS four times in a row. The power is definitely more on the top end, though... 4K+. You will want a new chip... as much to salvage the low end as to save your pistons from lean condition.

Cheers,

[PORSHIN]

Well, I have the 20/21's in my 3.2 and though i haven't been able to find a dyno in my area, I can honestly say they made an unquestioned difference to me. I won't turn it loose from a standstill because I feel it would possibly break something like a clutch or axle which are new too. Some guys in a yellow 5.0 mustang found out along with me that from a 30 mph rolling start in second gear it will leave the Mustang instantly and continually. When I hit third, he said he gave up. We stopped and chatted a little and they thought it was using nitrous or turbos. They wouldn't believe it was a naturally aspirated 3.2. The 20/21 cams have a greatly increased lift but the duration and overlap is just slightly increased because the fuel control system can't work properly with the intake pulses generated by more overlap than they have. These cams produce a pretty lumpy idle and will produce tremendous hp gains from about 4000 rpm to about 7000. To use them to their potential, you will need to use raceware rod bolts to keep it together at those rpms. You will also need stronger "performance" valve springs to keep the rockers on the cams and keep from "floating the valves". That will cause you to lose anything you would have gained. Also you will need a chip that will move the rev limiter up to 6800 or 7000. A cat bypass and free flowing muffler will also be in order. When you know what happens at 4000 rpm though it sure is hard to keep your foot out of it! LOL
Rob

[speeder]

Thanks for the info. I guess that a euro 3.2 w/ 964 cams, chip+ euro exhaust and sport muffler would be just about 3.6 power but lighter? Great motor in any 911, but imagine in an early car! Hang on!!

[marcesq]

Denis:

Thats exactly what I had in mind

[sp_cs]

Folks

Appears i may need to undertake a top-end rebuild at some point in the near future. I've a standard euro spec 3.2, 10.3-1 comp, SW 98Ron chip, standard intake etc etc.

Thinking of 964 or 20/21 cams as part of the rebuild.

Where can i expect to see gains/losses (if any?)

What else do i need to fit with the cams? ARP head studs? Uprated springs/retainers? Re-chip

I am also thinking possible 3.4 Mahle 9.8:1 conversion - would these cams be suitable?

Mine is purely a road car but hope to see some track action once the engine is sorted.

Thanks in advance

SP

[sp_cs]

Anyone?

[JeremyD]

Do you have to pass emissions? If so, then the 20/21 grind is about as agressive as you can get. Next up is the 993SS mechancial grind. It's about at the limit of the motronic's ability to catch the idle. Steve wong can program you a chip.

I have the 993 SS cams on my 3.4

It drives alot like an early S - need to keep it high in the rev zone - but rewards.

The rest of my engine is:

3.4 mahle 9.8 to one jugs
extrude hone intake
993ss cams (Dougherty Racing Cams)
arp rod bolts
Supertech Head Studs
enlarged throttle body
competition springs and retainers (EBS)
LN 1 3/4" SS Headers
MK Dual in - Single out

[Gunter]

Originally posted by sp_cs
Folks

Appears i may need to undertake a top-end rebuild at some point in the near future. I've a standard euro spec 3.2, 10.3-1 comp, SW 98Ron chip, standard intake etc etc.

SP

10.3 : 1 CR with single plug??????
What octane are you running?

[johndglynn]

Originally posted by Gunter
10.3 : 1 CR with single plug??????
What octane are you running?

It's a 231bhp Euro car Gunter, Shirish is in the UK. 98RON fuel.

[sp_cs]

Cheers JG, thats right, standard euro spec on 98ron, occassionally 99Ron Tesco stuff, whatever that really is - my car loves it!

JeremyD - some serious figures you're pushing there, good work!

I'm swaying toward 964 cams, as i doubt i'll be over 6k revs very much

Cheers
SP

[911-32]

Originally posted by TimT
Tec-2 engine management, TWM individual throttle bodies, appropriate crank and case mods to support high RMP longevity. Porting and smoothing of the heads. GT-3 oil pump. lightened flywheel etc....

Blimey 311rwhp nice

SP - I am sure you would like the 964s or 20/21s if you can do them as little while you are in there thing! I love my 993 Supercup cams.

[sp_cs]

Cheers Mr B! I'm thinking 964 too.....$650 on new billets from DRC

Waiting to hear what Tuthills have to say and also what TC from impactbumpers.com reports back with after his rebuild.

SP