3.0 to 3.2SS Build

[Jhogan0101]

Anybody have any thoughts on this setup?
Case/crank.................. Existing
Head studs..................New steel studs
Connecting rods...........Existing
Piston/Cylinders...........Mahle 98mm, C/R?
Cylinder Heads............Existing? Port intake? (82' sc)
Upgrade Cylinder Head valves/guides/springs?
Twin plug setup (necessary? 93 gas)
CIS to PMO 46mm
SSI Heat Exchanger..... Fitted for 3.0 or different?
Fan............................... Stock

Oil cooler........................Upgrade to elephant lines and 87' front cooler w fan thermostat?

[tharbert]

Welcome to the forum! You'll find a lot of expertise here. One of the best functions of this forum is the ability to search past threads. For instance, a search of "3.2ss" brought up 265 entries. Of the 265, you'll find answers to some of your question marks like twin plugging, piston selection, C/R, head mods, PMO's... It would help if you included a description of the car you have and your goal. Daily driver? Hot rod? DE? Racing? And, be sure to include a few pictures of your car!

3.2SS
3.0 to 3.2 conversion

Tom

[fred cook]

I did this about 2 yrs ago, but I used the Mahle 100mm pistons for a 3.3SS engine. A couple of things to consider based on your project list. First, have the rods rebuilt. Also, there is a procedure called shot peening that will relieve any stress points in the rods. Something you should never see again but that will help you feel comfortable about the engine when at high rpms. The second thing would be the port size in your cylinder heads. The late SC heads have pretty small ports. They can be opened up some, or you can swap to Carrera heads with the nice big 42mm intake and 41mm exhaust ports. I chose to use the Carrera heads and sold the SC heads to help offset the cost. Using the 46mm ITBs should work well with the large port heads. If you decide to stick with the CIS system, you will need to source one of the early SC airboxes and intake runners. They are quite a bit larger inside than the later ones. I used the CIS in a somewhat modified version on my 3.3SS and am quite happy with the performance. I agree that the ITBs would make more power, but I wanted to see what could be done with the CIS system. Plan your engine carefully, acquire as many parts as possible up front and , if you don't already have it, get Wayne's book on rebuilding the 911 engine. Good luck!

[mreid]

When you are going to all this trouble, why not new cams? I'm using GE80.

[Jhogan0101]

Thanks for the info guys.

[Farrell]

out of curiosity, can you take a 3.0 to a 3.4? i know Fred Cook says that he went from a 3.0 to 3.3ss and that sounds intriguing. the biggest benefit i see is there is more displacement available.

with a 3.3ss or 3.4 can you make better low end - mid range torque? so many people stick to a 3.2ss build with their 3.0 upgrade, is there a reason more people don't do 3.4 or 3.3ss, it seems like any chance to make more displacement would be sought after. is it cost that holds people back?

sorry I'm new to all this and am reading as much as i can.

Cheers,
TF

[mreid]

You don't have the mill the engine case to go from 95mm to 98mm.

[Farrell]

Originally Posted by mreid

You don't have the mill the engine case to go from 95mm to 98mm.

98mm is 3.4L?

[mreid]

It is 3.2 on 3.0 and 3.4 on a 3.2. Stock they have the same cylinder size (95mm), the cranks have a different stroke.

[Farrell]

Originally Posted by mreid

It is 3.2 on 3.0 and 3.4 on a 3.2. Stock they have the same cylinder size (95mm), the cranks have a different stroke.

So if I were to use 98mm cyinders with a 3.2 crank i would have a 3.4L displacement?

[Josh D]

Originally Posted by Farrell

So if I were to use 98mm cyinders with a 3.2 crank i would have a 3.4L displacement?

Yes, but you'll also need rods from 3.2 and pistons with 3.2 wrist pin offset and 23 mm wrist pins.

[mreid]

This is a very good point. You have to specify which crank to ensure the correct rods and pistons.

[Manda Racing]

I just found a stored box for 20 years with Carillo (sp?) rods I ran in a 3.0 for a season. I hope the surface rust hasn't ruined them.

[Farrell]

awesome, Thanks mreid and Josh D!

Manda - i would assume you can get them shot peened if there isn't too much rust.

[fred cook]

Originally Posted by mreid

You don't have the mill the engine case to go from 95mm to 98mm.

I used the LN Engineering "slip fit" cylinders. No case mods needed. A bit pricey, but top quality and no machine work required.

[fred cook]

Originally Posted by Farrell

So if I were to use 98mm cyinders with a 3.2 crank i would have a 3.4L displacement?

The 3.0 connecting rods and rod bolts are stronger than the 3.2 version. Something that is important considering that these are engines know to rev!

[wprater]

Originally Posted by fred cook

I did this about 2 yrs ago, but I used the Mahle 100mm pistons for a 3.3SS engine. A couple of things to consider based on your project list. First, have the rods rebuilt. Also, there is a procedure called shot peening that will relieve any stress points in the rods. Something you should never see again but that will help you feel comfortable about the engine when at high rpms. The second thing would be the port size in your cylinder heads. The late SC heads have pretty small ports. They can be opened up some, or you can swap to Carrera heads with the nice big 42mm intake and 41mm exhaust ports. I chose to use the Carrera heads and sold the SC heads to help offset the cost. Using the 46mm ITBs should work well with the large port heads. If you decide to stick with the CIS system, you will need to source one of the early SC airboxes and intake runners. They are quite a bit larger inside than the later ones. I used the CIS in a somewhat modified version on my 3.3SS and am quite happy with the performance. I agree that the ITBs would make more power, but I wanted to see what could be done with the CIS system. Plan your engine carefully, acquire as many parts as possible up front and , if you don't already have it, get Wayne's book on rebuilding the 911 engine. Good luck!

where can I find details on which heads will fit with a 3.0 case? Im looking to do a similar 3.0 to 3.3ss build soon!

[fred cook]

The main thing to look for will be heads from engines that have the same bore spacing. This will ensure that the heads will match the cylinder head studs. So, that means that basically any SC or Carrera heads will work. There has been lots of discussion about port size, with the general consensus being that the early SC heads with 39mm intake ports would seem to be optimal for a 3.2 or 3.3 engine. I used the Carrera head with the 42mm intake/41mm exhaust port sizes and have not found any issues due to the large ports. The end results will depend on things like compression, cams, ignition system and intake system. So, you need to think about things such as whether this will be primarily a track or street engine and if you want an engine that makes good low and mid range torque or one that makes lots of top end horsepower, etc. Just remember, "speed costs money, how fast do you want to go?".

[wprater]

Originally Posted by fred cook

The main thing to look for will be heads from engines that have the same bore spacing. This will ensure that the heads will match the cylinder head studs. So, that means that basically any SC or Carrera heads will work. There has been lots of discussion about port size, with the general consensus being that the early SC heads with 39mm intake ports would seem to be optimal for a 3.2 or 3.3 engine. I used the Carrera head with the 42mm intake/41mm exhaust port sizes and have not found any issues due to the large ports. The end results will depend on things like compression, cams, ignition system and intake system. So, you need to think about things such as whether this will be primarily a track or street engine and if you want an engine that makes good low and mid range torque or one that makes lots of top end horsepower, etc. Just remember, "speed costs money, how fast do you want to go?".

thanks for the tip, I'll continue to figure out exactly what carb/cam etc combo I like and go from there!