When i drop my motor this winter i was considering doing a 964 cam upgrade. Is this a worthy investment, and what would i expect to see in power gains? Thanks, Alex

 

Alex,

It really depends on how you drive the care whether its worth doing or not. 964 cams make a little more power in a slightly higher RPM range thats very useful for those days at the track.

Actual gains depend on many factors such as exhaust configuration and software.

 

What about sending your existing cams to a re-grinder?

Steve W.-Can the stock cams be reground for less?

 

Indeed, stock cams can be reground for less $$$ especially since 964 ones would need the PS drive to be machined off. New or refurbished rocker arms should always be used when installing new or reground cams, too.

 

Thanks guys. What do you think the best performance modifications would be for the 3.2 without forced induction? I definitely want to do some upgrades when the motor comes out but I'm really not sure what to do. Thanks a lot -Alex

 

I can picture Steve out behind the building testing cams after 9:00 PM revving an engine to 9,000 RPM's screaming "IT'S ALIVE, IT'S ALIVE!!!" only to be left wundering if it's the noise that drives him or some sick and twisted memory of his drive in that DP935?

 

I would suggest Stroking it!

 

Over the past few years I have done many modes to my 3.2. I think the best bang for the buck was my ECU chip and my SSI with two in one out M&K muffler. I have the 964 cams in my car. Like Steve said I think I lost a little down low but gained a little more from 4K and above. If you have not already done so get a chip from either Steve Wong or 911Max. Both are great.

 

I had done this to a stock 3.2 that I was using in my race car last year. The car gained about 10 Hp, and it was moved up the rpm band range. For me it was not a positive change.

Ed

 

Check out Jeff Alton's 3.4 or Ralph's 3.5 on pelican. You can make some decent power by going with a little more agressive cams - 20/21 if you still have to smog - 993 SS if you don't.

The 964 is more of a marginal increase IMO - and of course you can use your existing cam to regrind off.

 

My two cents.

Cat bypass, second exaust tip added to right side of stock muffler, SW chip for 215-220rwhp or 250+fyhp.

Send transmission out for a close ratio gear set.
This will alow you to run at a higher avarage HP and be much, much faster.

Reduce weight where you can. The right wheel set can reduce rotating and unsprung weight as much as 40 lbs. Take off as much weight from the rear as you can (duck tail?).

 

I'd only do these as part of an engine teardown. I had mine reground by John Dougherty (http://www.drcamshafts.com/) and went with his DC19, a bit hotter than a 964, but still supposedly smoggable. As mentioned above, it pulls better from mid-high R's.

The biggest bang I got was the B&B headers and re-chip I did a few years back. The cams just complimented it all.

 

I already have the cat by-pass and it seems to make a bit of difference. I planned on opening my muffler and taking everything out. The chip is definitely coming but I'm going to go through the motor first. I was considering taking off the whale tale but i cant decide. How about air boxes? Do aftermarket ones make any difference?

 

If you're really trying to find spare HP laying around, I'd get a set of headers, and do the exhaust right. Airbox is minimal if any....mostly sound. That said, a cone filter cleans up the compartment as does removing the heater blower and A/C.

 

I gutted a muffler once and it was very loud.
I am thinking of cutting up a spare I have and taking out everything to the right of the middle bulk head. Then, remove the tube to the exit between the two middle and first bulk head. Then make open up the area around the where the exit pipe went throught the middle bulk head a bit.
This will keep the resonance chamber, free up air flow, save some weight and should not be way out there.

I think the stock headers are ok with our no overlap cams. If one were to go with a more aggressive cam then the scavanging of equal length headers is a bigger plus. Otherwise, I do not see the cost payoff to be very good.

Compression, more CC,s and twinplugging can help a bunch.

So do we spend $2k on shinny headers, muffler, and oil lines or use it for bigger P&C's or light weight bumpers and interior.