Horsepower for all the (common) Porsche engine options Options

[IronHillRestorations]

Porsche factory HP numbers were minimum output, so an engine could make more but not less

[mepstein]

Great discussion gentlemen, good to have this all in one place.

I think the next interesting thing to collectively have a chat about is the crossover point on horsepower versus cost building out a more powerful flat four versus swapping in a six.

I know that’s apples versus oranges and how the car feels, but I think it would still be useful.

For example, total cost to build 130 hp flat for versus total cost to get that same horsepower with a flat six.

Cost is a difficult way to compare. You can spend 10k on rebuilding a six and not add any hp. You can also spend $10k just to fit the six into the car. The big difference between the 4 and six is it’s possible to buy a stock six from 110-275hp. A stock 4 is maxed hp at the very lowest stock 6.

The stock 3.2 I just purchased is about 220. That’s a super exotic build for a 4 and would cost triple the purchase price of my 3.2.
So it’s tough to talk in absolutes.

[Tdskip]

Good points, so it sounds like there is BALLPARK a cut over point around a 2.2 or 2.4 for what the six gives you vs when you need to start to built a really expensive 4 to keep up?

[mepstein]

Good points, so it sounds like there is BALLPARK a cut over point around a 2.2 or 2.4 for what the six gives you vs when you need to start to built a really expensive 4 to keep up?

I think that makes sense. I'm not trying to say a six is better than a 4 or vise versa but I think the six has the advantage of "off the rack", stock horsepower compared to a 4 with the disadvantage, unless you already have a 914-6, of needing to do a conversion.

[burton73]

It’s a very nice choice for a -6 conversion without the DME complications of the 3.2 or 3.6. A carbed 3.0 SC motor would be great as well once you replace the pistons and cams with ones that are not so limiting (and also replace any Dilivar studs).

Some of the guys have asked what is in this Engine. Scott Kinder built it for me and this is what it has inside. 

1978 3.0 SC big-port base (case, crank, rods, oil pump)
Custom JE Pistons, replated Nikasil cylinders, 9.8:1
New valves, 38/37 ports (stock) in 3.2 heads
ARP head studs & rod bolts
GE40 "Mod-S" cams
. PMO 46 carbs & manifolds
J WE custom curve on SC distributor to match the carbs/cams
 - 930 tensioners, idler arms--all rebuilt
, Otherwise just everything new or refinished, redone, rebuilt


At this point we can only guess. 230-250? We will dyno it tater when it gets it finished tune at Sea level. It is at Sandy UT with E @ PMB



https://vimeo.com/337332800

Bob B

[Rand]

It's a very slippery slope. There are 4 cylinder engines making 1000hp. Not TIVs mind you. More cylinders are going to provide longer longevity in general. But times change and technology does faster.

[mepstein]

It's a very slippery slope. There are 4 cylinder engines making 1000hp. Not TIVs mind you. More cylinders are going to provide longer longevity in general. But times change and technology does faster.

My boss bought a machine shop and said the guys there are making 900hp from the Suby turbo fours.

The 962 at our shop uses an air cooled 3.0 with a single turbo to get 780hp. Mid 80’s tech.

[Tdskip]

Good discussion, and man you guys have some awesome cars.

@mepstein - that was the trade off I was trying to get to, but as you and others point out it isn’t an apples v apples thing.

[914_teener]

Great discussion gentlemen, good to have this all in one place.

I think the next interesting thing to collectively have a chat about is the crossover point on horsepower versus cost building out a more powerful flat four versus swapping in a six.

I know that’s apples versus oranges and how the car feels, but I think it would still be useful.

For example, total cost to build 130 hp flat for versus total cost to get that same horsepower with a flat six.

Total power at the crank? Also the converted power is torque.

Torque is what you feel.

[thelogo]

1.7 flat 4 - 79

(IMG:style_emoticons/default/WTF.gif) were they thinking

[Larmo63]

Tom, I'll take you for a ride in my /6.

You'll want a six.

Believe me.

[914_teener]

It's just not worth it to build a four for real torque or horsepower unless you are keeping it stock or near stock. A 2056 is probably your best bet. Done right 15k. There is really is no comparison to a six.


Like Larwrence said....ride in one or drive in one...end of discussion.

[mb911]

Oh also want to point this out as some people get very confused from inaccurate advertising. K&N air filters add zero hp.. Don't buy into the hype it's complete b.s... I am not arm chair QB ing here this is from real data in my former life as an experimental aircraft engine builder.

[Tdskip]

Thanks for all the discussion. I’m definitely putting the 3.2 in. I’ve just been trying to educate myself on other engine options as well ( part of figuring out what to do with the spare 2.7 L ) and so forth and wished there was one place that had everything together, so I thought I’d start the thread.

[Coondog]

Just do it.....but don’t forget about your Trans and Brakes.

[VaccaRabite]

It's a very slippery slope. There are 4 cylinder engines making 1000hp. Not TIVs mind you. More cylinders are going to provide longer longevity in general. But times change and technology does faster.

My boss bought a machine shop and said the guys there are making 900hp from the Suby turbo fours.

Usually for just long enough for the dyno run before the engines scatter.

The BS my Suby brethren (IMG:style_emoticons/default/bs.gif) do to their engines (spending money they don't have on a very powerful and equally short lived motor) and then complaining bitterly about horrible Subaru reliability... (IMG:style_emoticons/default/blink.gif) (IMG:style_emoticons/default/barf.gif) Ring-land failure. Premature clutch failure. Asshats. "How do you have a WRX with over 100K miles and still on the original clutch? Mine failed in 20K miles..." There are not enough eyerolls.

Zach

[mepstein]

It's a very slippery slope. There are 4 cylinder engines making 1000hp. Not TIVs mind you. More cylinders are going to provide longer longevity in general. But times change and technology does faster.

My boss bought a machine shop and said the guys there are making 900hp from the Suby turbo fours.

Usually for just long enough for the dyno run before the engines scatter.

The BS my Suby brethren (IMG:style_emoticons/default/bs.gif) do to their engines (spending money they don't have on a very powerful and equally short lived motor) and then complaining bitterly about horrible Subaru reliability... (IMG:style_emoticons/default/blink.gif) (IMG:style_emoticons/default/barf.gif) Ring-land failure. Premature clutch failure. Asshats. "How do you have a WRX with over 100K miles and still on the original clutch? Mine failed in 20K miles..." There are not enough eyerolls.

Zach

They are race engines. The good thing is I now have machine shop availability at reasonable prices.

[defianty]

Thanks for all the discussion. I’m definitely putting the 3.2 in. I’ve just been trying to educate myself on other engine options as well ( part of figuring out what to do with the spare 2.7 L ) and so forth and wished there was one place that had everything together, so I thought I’d start the thread.

To educate myself on six cylinder engines I bought this book.

https://www.amazon.com/Porsche-911-Red-Book...s/dp/B015QNJUCE

It lists every engines spec, I've referred to it so many times my copy is starting to get a bit tired. A great reference book.

[914Toy]

Tom, I'll take you for a ride in my /6.

You'll want a six.

Believe me.

(IMG:style_emoticons/default/agree.gif)

[76-914]

(IMG:style_emoticons/default/stirthepot.gif)