Enthusiastic Newb Needs Some Engine Build Advice: What Would You Do?

[ScottArizona]

Man...so many options in this world. I appreciate the advice to just hot rod the 3.2. To clarify, I 100% intend to do that...just not in this car! ADDvanced, the 3.2 is super solid and I want to keep it...and install it into a future project (long hood, street/DE combo lightweight outlaw screamer, maybe on a 912 chassis is my dream).

That is why I want the 3.0 back into the SC, but, I would hate to feel a reduction in power, thus my conundrum (and questions). And, since I have to dive into the engine anyway for the stud repair and refresh, might as well improve things while I can.

And I'm not dead set on 50hp. Car already has no-heat headers and a bursch exhaust (not a huge fan of the sound, which is a bit too sedate). I like Aaron's idea! That sounds amazing.

A little concerned about the suggestion that huge elevation swings may pose a problem though. I have never owned a car with carbs, so I'm a little behind the 8 ball in terms of my understanding of the limitations of carbs.

Also, even if my "built" 3.0 was not much faster than my current, internally stock 3.2, I think I'd be fine with that. The 3.2 seems to feel just a bit lazy, so if at a minimum I could get improved throttle response and "revability," that would probably be just fine.

[Bill Verburg]

Folks tal hp but what most street users want is torque

Here's a comparison of some typical torque curves seen in the 911 world
the rust colored one is a carbed/cammed/headered 3.4

[BURN-BROS]

I've never been a fan of the 3.2 in stock form.

you can substitute PMO Throttle bodies and a spicy EFI cam and your altitude issues would go away. There are new ECU packages out now with impressive self learn capabilities.

[Trackrash]

It's a euro SC with the big port heads?

With bigger P&Cs and headers and a cam like a 964 couldn't you still use your CIS and gain a good jump in power?

I'm not ready to give up my carbs quite yet. But at the cost of carbs vs ITBs, ITBs make a lot of sense. The problem with Webers is the gas that is available now is not formulated for carburetors.

[GaryR]

He's missing the CIS system..

[75 911s]

Sell the running 3.2 and buy a 3.6

Put the 3.0 parts in oil and bags and store them.

[ScottArizona]

Originally Posted by GaryR

He's missing the CIS system..

Actually, I have it...but I'm just unclear of the condition since its been on a shelf for over a decade.

Thanks for all the advice guys. I want to keep both engines because I eventually want two air coolers!

[ScottArizona]

Originally Posted by Trackrash

It's a euro SC with the big port heads?

With bigger P&Cs and headers and a cam like a 964 couldn't you still use your CIS and gain a good jump in power?

I'm not ready to give up my carbs quite yet. But at the cost of carbs vs ITBs, ITBs make a lot of sense. The problem with Webers is the gas that is available now is not formulated for carburetors.

So, school me on ITB's. I Would still need some modern, computer-run engine management system though right? Isn't that like voodoo magic to set up? I guess that would solve the elevation swing issue though, if I'm not mistaken. And I'm assuming with a nice ITB EFI retro-fit, I could use aggresive cams and the the throttle response would be carb-like?

And yes, its the big-port, higher compression euro motor. In other words, stock for stock very similar power output as a U.S. 3.2, which is why I was assuming it should not be too hard to eclipse the power of the internally stock 3.2 with some "while you are in there" mods to the euro 3.0.

[Sboxin]

Originally Posted by BURN-BROS

3.0 liter base
98mm bore
mod S cams
Twinplug
10.5/1 comp
SSI exhaust
PMO 46
M&K R muffler

This combo should get you around 280hp, strong midrange and a redline of 7500 rpm

Agree with Mr. Burn . . .
A friend has something similar to this in a race car - and he can be as fast as our 3.6/3.8L race engine . . . big difference is in weight 200# lighter, etc.

Regards,

[rswannabe]

If I were rebuilding the 3.0 SC motor, I'd do it as a 3.2 short stroke, twin plug with 10.5:1 compression and run a Mod S/GE40/DC40 cam at the minimum. Carbs are good, but EFI with individual throttle bodies are better (if more expensive). This would easily get you the extra 50 hp you stated as a goal. Bump the cam to something more aggressive but still streetable like a GE 60/DC60 and you can be up in the 280 crank HP range.

You say you like the simplicity and looks of the carbed motor. An EFI ITB setup can look just as good, and is more dribveable and less finicky than carbs. I have a lot of experience with both and much prefer EFI at this point.

Here is my 3.8 EFI ITB motor that is backdated to look like and early carb motor.

[BURN-BROS]

Originally Posted by ScottArizona

So, school me on ITB's. I Would still need some modern, computer-run engine management system though right?

Yes

Originally Posted by ScottArizona

Isn't that like voodoo magic to set up?

Not so much anymore....new systems are self tuning and are getting downright impressive. You still require basic knowledge, but the specific skill sets may not be required in the near future....or even today.

Originally Posted by ScottArizona

I guess that would solve the elevation swing issue though, if I'm not mistaken.

Yes

Originally Posted by ScottArizona

And I'm assuming with a nice ITB EFI retro-fit, I could use aggresive cams and the the throttle response would be carb-like?

Yes!

[mepstein]

Sell the 3.0 & the 3.2. Buy a good 3.6. Chip, exhaust and if you still need more, change cams. 275-300hp easy and no hassle. With a strong 3.6, you will be pretty and won't be chasing expensive mods to the smaller engines.

[pmax]

Originally Posted by Trackrash

What ever you do, make sure all the components you choose are well suited to work in harmony.

I suggest giving some thought to the 915 as well in the pursuit of engine power.

[Josh D]

Here’s a less costly build that offers good bang for the buck:

98mm P/C (used cylinders bored and plated)
9.5:1 CR (single plug)
964 cams (ground on stock cams)
TBitz EFI (reuse stock intake and TB)
Early HE’s or SSI

Should be good for 230-240 crank HP and great midrange torque. Get car down to about 2400 lbs and it’ll be a lot of fun.

This is essentially what i’m doing.