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Cheshire Cat

3.0 SC engine build suggestions

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Well, the time has come to mess with the engine. So, my favorite parts is here - what do you think I should do with hardware?

Now I have a stock 3.0 SC 1982 engine with Triumph ITB`s and EFI (seems like 44-45mm TBs) on COPs, exhaust will be sorted finally when I`ll drop the engine, so the plans are:

3,2SS with 10.5-11 CR pistons, hopefully single plug since I`m using 98 petrol but suggestions are welcome. Street car (with some track activities once in a blue moon) but keen to use 4000 to whatever RPM range

Camshafts, probably 964 profile, but still thinking, intake and exhaust porting? Headstuds etc?

Enlighten me gents. 

Aiming to have 250 or so at the wheels (dreams-dreams)...

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I am not an expert, but from what I have gathered, that sort of compression with the large 911 head design struggles with the single plug. As it is offset, twin plugging is a good idea. @Mike D'Silva is the resident rebuild expert, so you should talk to him. 

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Since you are already running CoP's going to twin plugs is about as easy as it will ever get.  All you are really up for is another set of Cop's and extra harnesses ($50 to 110 each cylinder), machining heads for second plug (when done as part of full head reconditioning I was charged $700) and machining access holes into the lower rocker covers (don't know what that costs as I've gone to 964 style covers).  Like Jeff infers, (modestly) more power at 8 to 10 degrees less total advance would be the payback.

 

However I do warn you that as soon as you unbutton these engines the minimum cost increment for anything appears to be a $1000!

For example, you can buy a set of Carrera 3.2 cylinders from EBS Racing that have been bored and replated to 98mm that would suit your 3.2SS build for $360USD outright each.  Alternatively you could buy a set of used 3.2 cylinders for around $1000 (Yes and that's if you can find any!) and have them bored and replated for $2,500 locally (or $2,000 at NZ Cylinders but I'm still making up my mind with them).  KS or Mahle cylinders are both equally fine for replating.

A set of 98mm JE pistons will be almost $2,000 or Mahle Motorsports closer to $3,000.  So eye wateringly expensive and our current exchange rate isn't helping at all!

I suggest you do some Google searches using "Pelican Forum" and "3.2SS" to help you arrive at the specification you want and then do some careful "worst case" estimates that include having to replace all the valves, the springs, sprockets and rockers along with all the other normal wear parts like bearings ($1,200!), valve guides, cam chains, slippers etc. so there are no surprises.

 

 

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As @Peter M is suggesting, just a standard rebuild is super expensive. Beyond all of the custom things I have had to do, just replacement parts like chains, chain guides, bearings, etc add up. I also had to get all of my rockers resurfaced, valves lapped and checked. It is a very expensive exercise before you even start to look at upgrades.

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4 hours ago, Peter M said:

Since you are already running CoP's going to twin plugs is about as easy as it will ever get.  All you are really up for is another set of Cop's and extra harnesses ($50 to 110 each cylinder), machining heads for second plug (when done as part of full head reconditioning I was charged $700) and machining access holes into the lower rocker covers (don't know what that costs as I've gone to 964 style covers).  Like Jeff infers, (modestly) more power at 8 to 10 degrees less total advance would be the payback.

 

However I do warn you that as soon as you unbutton these engines the minimum cost increment for anything appears to be a $1000!

For example, you can buy a set of Carrera 3.2 cylinders from EBS Racing that have been bored and replated to 98mm that would suit your 3.2SS build for $360USD outright each.  Alternatively you could buy a set of used 3.2 cylinders for around $1000 (Yes and that's if you can find any!) and have them bored and replated for $2,500 locally (or $2,000 at NZ Cylinders but I'm still making up my mind with them).  KS or Mahle cylinders are both equally fine for replating.

A set of 98mm JE pistons will be almost $2,000 or Mahle Motorsports closer to $3,000.  So eye wateringly expensive and our current exchange rate isn't helping at all!

I suggest you do some Google searches using "Pelican Forum" and "3.2SS" to help you arrive at the specification you want and then do some careful "worst case" estimates that include having to replace all the valves, the springs, sprockets and rockers along with all the other normal wear parts like bearings ($1,200!), valve guides, cam chains, slippers etc. so there are no surprises.

 

 

Yeah I know the drill. 

Don`t get the point of buying a set of 3.2 cylinders to bore them if I could do the same with my ones. Same 3 mil added...

The thing with twin plug is they are not as crucial in Aus as it is in the US. The petrol quality is the key. Googled it.  

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Actually the difference in fuel between Aus and the US is not as much as it seems. They measure octane differently to what we do, so from memory our 98 is roughly the same as their 93.

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If you would mention a few names in Australia (I`d prefer Melbourne) who does all that machining stuff I`d be quite happy and if you name some ruff money numbers to aim I`d even happier :)

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3 hours ago, Cheshire Cat said:

Yeah I know the drill. 

Don`t get the point of buying a set of 3.2 cylinders to bore them if I could do the same with my ones. Same 3 mil added...

The thing with twin plug is they are not as crucial in Aus as it is in the US. The petrol quality is the key. Googled it.  

The 3.2 cylinders don't have the fire groove machined into the top of the cylinders like SC cylinders which can cause problems when they are over-bored.

True about twin plug not being mandatory and your decision will be based on factors no doubt different to mine.  I think I was pretty even handed about the benefits and costs in my earlier post.

But you are right of course, you can Google all this.

 

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Why do the parts cost so much more? Because people pay, or is there some other reason?  A set of LSx pistons is nowhere near that much.

i do find it funny that some of us drop 20k on an engine with pretty modest power outputs in the scheme of things.  Don’t get me wrong what Chesure cat is doing is exactly the same as what I would like to do, but the value is so bad compared to the rest of the car world.

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FWIW, if your Ps & Cs are still in spec, I wouldn't bother with going 3.2.  Also, as was stated, 3L cylinders don't take well to being bored to 98mm - not enough meat left at the top.  IMO, $5k plus to get an extra 200cc is not a great bang for buck equation.  Of course, if your Ps & Cs are cactus, that's a whole different story.

Anything over about 10:1 needs to be twin plugged.  You have an '82 engine which means it's already at 9.8:1 and the pistons swirl and squish the AF mixture under the plug which non OEM pistons don't do AFAIK.  So save your $700 or $800 twin plugs for where it will be of most  benefit - ports, cams, exhaust.  You already have a good ITB setup.

250RWHP equates to about 300 crank HP.  This is a big stretch for an N/A engine of this size both technically and financially.  Even if you did get 100hp/L you might find it a pig to drive on the road.  Also, high comp generally means lots of heat which means you'll have to upgrade your cooling system.  The slope gets very slippery...

Good luck with whatever you decide.

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Mark,

I suspect running standard pistons may limit your cam choices due to tight piston to valve clearances.  Maybe fine with 964 cams but anything else may not be workable.  However I'm sceptical that 964 cams and 3 litres will achieve 250rwhp with a muffler.

I think the most sensible approach - cost and streetability - to achieve this hp would be to keep the engine near stock with just do the usual refresh items and upgrades such as ARP rod bolts and all steel head studs and just stick a turbo on it.

Uncle's/Martin's/Mike Lowrrrry's two famous threads would be a good resource.  

 

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11 hours ago, Coastr said:

Why do the parts cost so much more? Because people pay, or is there some other reason?  A set of LSx pistons is nowhere near that much.

i do find it funny that some of us drop 20k on an engine with pretty modest power outputs in the scheme of things.  Don’t get me wrong what Chesure cat is doing is exactly the same as what I would like to do, but the value is so bad compared to the rest of the car world.

Say JE pistons cost something around 1000usd without shipping, pretty standard 95mm bore and 98mm a hundred or so more. 

But seems like to bore out stock 3.0 sc cylinders not the best idea, so we coming to the point of buying a set of cylinders which is either used one or a new and it will add another grand or more (talking used one option).

Then comes bore out - another 600-700, maybe a bit less bucks. Heads porting etc will cost something else. Again the twin plug. 

I'm gonna do this myself and really slow so, I will have plenty of time to consider my options. 

9 hours ago, bumble said:

FWIW, if your Ps & Cs are still in spec, I wouldn't bother with going 3.2.  Also, as was stated, 3L cylinders don't take well to being bored to 98mm - not enough meat left at the top.  IMO, $5k plus to get an extra 200cc is not a great bang for buck equation.  Of course, if your Ps & Cs are cactus, that's a whole different story.

Anything over about 10:1 needs to be twin plugged.  You have an '82 engine which means it's already at 9.8:1 and the pistons swirl and squish the AF mixture under the plug which non OEM pistons don't do AFAIK.  So save your $700 or $800 twin plugs for where it will be of most  benefit - ports, cams, exhaust.  You already have a good ITB setup.

250RWHP equates to about 300 crank HP.  This is a big stretch for an N/A engine of this size both technically and financially.  Even if you did get 100hp/L you might find it a pig to drive on the road.  Also, high comp generally means lots of heat which means you'll have to upgrade your cooling system.  The slope gets very slippery...

Good luck with whatever you decide.

Good stuff mate. I'll crack it open and shall see how's it going. Probs. Will not mess with 98mm pistons but will do the 10.5 to 11 CR

12 hours ago, Peter M said:

The 3.2 cylinders don't have the fire groove machined into the top of the cylinders like SC cylinders which can cause problems when they are over-bored.

True about twin plug not being mandatory and your decision will be based on factors no doubt different to mine.  I think I was pretty even handed about the benefits and costs in my earlier post.

But you are right of course, you can Google all this.

 

Thanx for pointing out the ring problem. I should investigate more. 

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3 hours ago, Cheshire Cat said:

Then comes bore out - another 600-700, maybe a bit less bucks. 

Because the cylinders are aluminium it's more that just a bore out as they have to be then re-Nikasil plated.  $2000 to 2,500AUD is going rate.

If you have a plenty of time and a touch of luck, usable 98mm pistons and cylinders come up for sale on Pelican occasionally.

I wish you luck with your endeavours.  

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4 hours ago, Peter M said:

Because the cylinders are aluminium it's more that just a bore out as they have to be then re-Nikasil plated.  $2000 to 2,500AUD is going rate.

If you have a plenty of time and a touch of luck, usable 98mm pistons and cylinders come up for sale on Pelican occasionally.

I wish you luck with your endeavours.  

2000-2500? are they made of titanium with some gold and platinum?

btw. googling around for rough prices I`ve found a set of 964 3,6 c\p, is it possible to use any of those?

got my answer for the 3,6 cps. spigots and heads should be machined, now the question is who could do this here and how much

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Your crankcases would need to be bored to allow the 964 cylinders to fit.  Sorry I'm not sure how the deck height is effected as I've been researching 3.4's rather than 3.2SS.  At worst it may require special conrods or pistons as well.

It's a pity though as those 964 parts are plentiful and cheap from cars being stripped for Singer I presume.

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29 minutes ago, Peter M said:

It's a pity though as those 964 parts are plentiful and cheap from cars being stripped for Singer I presume.

...in short, wasted.

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Theory is that a 3l, can get up to 300 hp without significant internal work, so 250hp should be relatively easy. Parts below will be circa $15k. 1) SSI's and decent muffler should b the start. Peter Starr muffler is best around. No drone, awesome sound. 2) PMO's. 3) Matching S Cam for PMO's. 4) High comp piston and rings. You can go more, but cost will keep going up. Above four are best bang for your buck IMO. Good luck.

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1 hour ago, FL7 said:

Theory is that a 3l, can get up to 300 hp without significant internal work, so 250hp should be relatively easy. Parts below will be circa $15k. 1) SSI's and decent muffler should b the start. Peter Starr muffler is best around. No drone, awesome sound. 2) PMO's. 3) Matching S Cam for PMO's. 4) High comp piston and rings. You can go more, but cost will keep going up. Above four are best bang for your buck IMO. Good luck.

I am not sure where those figures are from. 300hp out of a 3l is a LOT, and that is figures at the crank. have a look at @Pork Chops did with his 3.2SS. A lot of internal goodies there and he got 220hp at the wheels (so maybe 260-270 crank). 

 

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That is the general rule what can be achieved. Not at the wheels. Not necessarily from those 4 stages, bit what these engines can get without massive internal stressed. 3.0l - 300hp. 3.2l - 320hp. 3.6l  - 360hp. This is from the air-cooled engine experts who have built race engines. Those 4 stages are most efficient and easily reversible. Interesting that a 911 engine book I read quoted those 4 items as upgrades. Exactly what my expert air-cooled engine builder told me. 

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If u start off with an oz delivered u have around 190hp. PMO's, S cam and SSI's and exhaust will increase this by around 50-60. Whether it is 250/60 or 300. The power to weight makes this very fast. Suspension and tyre upgrades a must. I have plans to do these mods on either a 3l or 3.2, with a wide body to keep the power in check

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4 minutes ago, FL7 said:

If u start off with an oz delivered u have around 190hp. PMO's, S cam and SSI's and exhaust will increase this by around 50-60. Whether it is 250/60 or 300. The power to weight makes this very fast. Suspension and tyre upgrades a must. I have plans to do these mods on either a 3l or 3.2, with a wide body to keep the power in check

250 will be fine yeah, but it will take a real screamer to get to 300! lots of headwork etc. 250 is about right if you take all the easy gains.

you won't need a widebody to keep the power in check. it looks cool though

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2 hours ago, FL7 said:

Theory is that a 3l, can get up to 300 hp without significant internal work, so 250hp should be relatively easy. Parts below will be circa $15k. 1) SSI's and decent muffler should b the start. Peter Starr muffler is best around. No drone, awesome sound. 2) PMO's. 3) Matching S Cam for PMO's. 4) High comp piston and rings. You can go more, but cost will keep going up. Above four are best bang for your buck IMO. Good luck.

300 is achievable with really hard racing solutions which is not my case unfortunately. But I used to be at this level of optimism a while ago. Now - seems like I was wrong. Probs I'm quite wrong being wrong but we shall see :))

 

37 minutes ago, MFX said:

I am not sure where those figures are from. 300hp out of a 3l is a LOT, and that is figures at the crank. have a look at @Pork Chops did with his 3.2SS. A lot of internal goodies there and he got 220hp at the wheels (so maybe 260-270 crank). 

 

Jeff, Nick said there that nothing was done with the heads and this is quite a big part of the power numbers. His setup really nice and very street useable. I'd go just a tiny bit further but it will take a while. 

4 minutes ago, clutch-monkey said:

250 will be fine yeah, but it will take a real screamer to get to 300! lots of headwork etc. 250 is about right if you take all the easy gains.

you won't need a widebody to keep the power in check. it looks cool though

With lots of headwork you'll be able to get 100+ hp from 1 liter. But it takes thing further, rods, crank to reach higher rpm, valves, then exhaust and intakes to provide more air to get it. Slippery slope. Which is fine if you packed with money. 

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7 minutes ago, Cheshire Cat said:

300 is achievable with really hard racing solutions which is not my case unfortunately. But I used to be at this level of optimism a while ago. Now - seems like I was wrong. Probs I'm quite wrong being wrong but we shall see :))

 

Jeff, Nick said there that nothing was done with the heads and this is quite a big part of the power numbers. His setup really nice and very street useable. I'd go just a tiny bit further but it will take a while. 

With lots of headwork you'll be able to get 100+ hp from 1 liter. But it takes thing further, rods, crank to reach higher rpm, valves, then exhaust and intakes to provide more air to get it. Slippery slope. Which is fine if you packed with money. 

yep, if you have the  head apart for recondition may as well give them a tickle :)

as peter said, won't be hard to go twin plug just to get the most out of what you have for relatively little modification.
a healthy 250hp with a good midrange will be far more satisfying than a peak 300hp.

take the easy gains, don't get caught on the slippery slope!
 

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3 minutes ago, clutch-monkey said:

yep, if you have the  head apart for recondition may as well give them a tickle :)

as peter said, won't be hard to go twin plug just to get the most out of what you have for relatively little modification.
a healthy 250hp with a good midrange will be far more satisfying than a peak 300hp.

take the easy gains, don't get caught on the slippery slope!
 

It's so tempting though:))

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