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Gearhead1432
How much power have people been able to get out of a stock displacment motor? Torqure and Hp?

I can recall reading about people getting 120hp from 1.7L type one motors years ago. That is on pump fuel.

With the technology available today I would think that volumetric efficiency could be pushed further than before while maintaining reliability on the street.

So is 130-160hp out of a 2.0 totaly screwy.gif

I know Porsche did it years ago with a couple diferant 2.0L motors like the 901/911 or 587 (street motors not track). However, they were radicaly diferant compared to the simple type 4. ....

-Rob
Dave_Darling
You could probably get about 300 HP out of a 2.0 displacement motor.

For about thirty seconds. At a cost rivalling that of your average house. On some exotic type of fuel. With huge amounts of boost. After five years of development. (At many times the cost of the average house.)

Constraints are what give you an idea of where to go. You mention pump gas--that's one good thing to know. (Regular-grade? CA-super 91 octane? The 94 you can get some places? Something else?)

Forced induction or naturally aspirated?

How long is it supposed to last?

Is cost an object? What kind of budget is available?

Is a peaky powerband OK, or do you want a fat mid-range for easy driving?

....And on and on and on. Answer these types of questions (and many others!) and you can start figuring out reasonable limits.

--DD
alpha434
QUOTE (Dave_Darling @ Jan 3 2006, 07:26 PM)
You could probably get about 300 HP out of a 2.0 displacement motor.

For about thirty seconds. At a cost rivalling that of your average house. On some exotic type of fuel. With huge amounts of boost. After five years of development. (At many times the cost of the average house.)

Constraints are what give you an idea of where to go. You mention pump gas--that's one good thing to know. (Regular-grade? CA-super 91 octane? The 94 you can get some places? Something else?)

Forced induction or naturally aspirated?

How long is it supposed to last?

Is cost an object? What kind of budget is available?

Is a peaky powerband OK, or do you want a fat mid-range for easy driving?

....And on and on and on. Answer these types of questions (and many others!) and you can start figuring out reasonable limits.

--DD

Water cool the heads and add bi turbo. Maybe not three hundred, but an easy two.
Bleyseng
a Jake Raby kit 2270 would be in the ballpark of what you are talking about. With Nikkies and FI its already here (140-160hp) but costs $$$$$.

alpha434
oh yeah- and weld the heads to the cylinders and forget about pump gas. Run the compression at 18:1.

Hehe. If anything goes wrong, you can take out a whole city block.
Gearhead1432
Fuel; 91/92 you can get any where

Induction; FI or carbs? I hapen to be partial to the later, but modern FI is impressive

Endurance; 100K miles sound good?

Cost; less than the equivilant 901/911 wink.gif

peaky power bands are fun... that's why I like smaller motors.

I figure that I would just spend more $$$$ on heads and none on upping the dissplacement. Piston upgrade is nessesary however. Probably JE or something like that.

Other wise the same performance could probably be had at a larger displacement with less tuning. But that would take all the fun away.

I like motors like the 302 Z-28 with two 4bbls drooley.gif or old 283 MFI 'vette motor
Gearhead1432
QUOTE
If anything goes wrong, you can take out a whole city block.


I like your thinking. The neighbors would feek out when it started up!
Jake Raby
Man, it never ceases to amaze me how hard you guys make this....

Want 155 ponies??Shell out about 4500 bucks for the 2270 kit and be done with it...
Brett W
To hell with pump gas, drop the compression to 6.5, throw some nitro methane at it and run 45lbs of boost.

Oh sorry you wanted this engine to last more than one trip to the gas pump. Sure would be fun though.
dmenche914
Sure wish us folk in the San Fransisco bay area could easliy find 92 Octane. several years ago it dissappeared from near all the service stations (at least all the station i have gone too)
We recently had a big price drop in gas, we now pay closer to the national average. Had to do with the katrina thing, and the EPA waiving the special california only gas mix (with ethonal and /or MTBE), beause of gas shortages. Seems the special gas not only reduced milage, power and rotted rubber parts in older cars, it also costs more!

Hoping for more hurricanes!
Jake Raby
we have 93 octane at every pump, sometimes 94 and the Citgo station sells 100 octane...

Just move out of California and you can experience it too....
Gearhead1432
QUOTE (Jake Raby @ Jan 3 2006, 11:08 PM)
Man, it never ceases to amaze me how hard you guys make this....

Want 155 ponies??Shell out about 4500 bucks for the 2270 kit and be done with it...

Come on Jake, that would be too easy. biggrin.gif (however your kit is "plan B")

I'm sure you can appreciate people who have the desire to do something a little different. "Thinking out of the box." Some people want to put Subs in their 914, others small block chevys.

So, if joe blow down the street can build a reliable 400hp 350 for his Camaro, why can't I build a 140hp 2.0 type 4? Or is my logic missplaced? wacko.gif confused24.gif

As for pump gas around here, you can find 91-92 at most places. There are a few places you can get 100+ race fuel.

-Rob
lapuwali
The key here is specific power: hp/liter.

In a two-valve engine, getting more than 70hp/liter is getting into race engine territory. The cam required to do better than this usually produces poor low-speed drivability. Four-valve engines do better, usually 80hp/liter before it gets too cammy for street use. Variable valve timing changes the picture completely, but we'll ignore that, for now.

A 70hp/liter 2.0 would indeed make 140hp. There are several street engines in this neighborhood. The Euro-tuned Alfa twincam makes 140-150hp in 2.0 street form. Even the smog-choked, low compression, very mild cammed US version did 115hp (58hp/liter). The '72-'73 911E made 165hp from a 2.4 Six, or 68hp/liter. The 911S of that year did 190hp (77hp/liter), but it's generally considered to be pretty wild for day to day street use.

The stock 2.0 Type 4 only does 48hp/liter, so there should be a lot of room for improvement here. The number Jake just threw out 155 from 2.27L is 68hp/liter, so you should (theoretically) be able to get 135hp or thereabouts from 2.0L. I suspect that since building a 155hp 2270 costs about the same as building a 135hp 2.0, that there's little point in doing the latter, unless you're operating under racing rules that limit you to 2.0 liters.
Jake Raby
The difference is the RPM range needed to make the power.. A 135HP 2 liter HAS to turn and make power to 7,000 RPM to make the numbers- The 2270 only needs 5,000 RPM to make 135 HP.

Tell me which one is the easiest to drive with the best torque and usable power.....

Tell me which one will last the longest.... (remember that RPM = wear)

HP is worthless unless you intend to operate at 5,252 RPM + ALL THE TIME, thats because Tq and HP cross at 5,252 RPM.

It's all about torque, once you realize HP sucks and torque rules, you'll start enjoyiong the car a lot more...
Gearhead1432
Hmm, maybe I'll have to re-evaluate this. I think a 6.5K red line is in order. It must be able to go on long *spirited* drives in exccess of 1000miles.

New example. It maybe a poor one considering it is a member of the 547 family, but none the less, here it is... 1966cc (2.0) 2000GS motor. 130hpDIN @ 6.2k rpm, and 131 Lbs/ft.
Jake Raby
It's a 4 cam with twin ignition and a full hemi chamber...

It's not even on the same planet as the engine's we are discussing here and it was designed for a 1200 pound aluminum bodied car.

I have driven one in a 59 Carrera GT and the powerband was worthless, slow as dirt..
here she is, this car raced at Leman in 1960 piloted by Bill Romig- yes those are aluminum brake drums...

This engine made 138HP as a 1600, Abarth tuned..
user posted image
Gearhead1432
That's a great looking speedster. drooley.gif

But you said it's a 1600, that must be a 547 or other earlier motor, I was refering to the 587 2000GS motor found in the Carrera2. wink.gif

It looks like 110 hp at 3.5Krpm is easy to make. And that is with out a real header and with 40mm carbs.

So add better heads with cam... maybe 44IDFs or some kind of FI... tangerine header....

It looks like another 25hp can be found in there.
Brew
QUOTE (Jake Raby @ Jan 4 2006, 05:06 PM)

HP is worthless unless you intend to operate at 5,252 RPM + ALL THE TIME, thats because Tq and HP cross at 5,252 RPM.


Jake, I understand and agree with your post, except for this quote. Obviously, just because Hp and TQ cross at 5252 doesnt mean that's where either of them necessarily peak.

Or am I reading it wrong?
Jake Raby
Nope, the peak is dictated by the overall engine combo.

The fact is that below 5,252 RPM Torque is always higher than HP.

Above 5,252 RPM HP is always higher than torque..

So HP is not huge unless your engine is very much still revving and making power past 6K.

Dyno graphs that don't cross HP and torque at 5,252 RPM are not accurate- the formula is incorrect.

Here is an example of a correct dyno graph
user posted image
Brew
Ok, I get ya now. Thanks!
lapuwali
Jake, hp (sae) = torque (ft/lbs) x rpm / 5252. The 5252 is just there to correct the units being used. If one used Watts for power and measured torque in Newton meters, the correction factor would be different, and thus where they curves crossed on the graph would be different, but the results would be just as valid.

You can also show graphs where HP and torque are plotted on different scales, and there, the curves would also cross at a different place, but would still be valid and correct.

There's nothing magic about 5252, it's just a result of the units being used.
Jake Raby
Exactly....

Thats really apparent on engines that make all their power below and will not even rev 5,000 RPM- Like my Pinzgauer engine...

My whole point is that HP is way over rated and generic for street cars that spend their at midrange RPM.
Gearhead1432
Great info Jake.
I hadn't realy looked at it that way before.
grantsfo
The only cost effective way to get reliable HP is to go with a six. biggrin.gif
Jake Raby
Narrow minds all think the same.
grantsfo
QUOTE (Jake Raby @ Jan 4 2006, 08:09 PM)
Narrow minds all think the same.

Jake when you can sell a 150 hp engine for around $7500 my mind will open to the incredible possibilities offered by your genious with T4 engines. My sense is your production volumes will never get you to that price point. So I'd rather pick up a used 6 with a warranty for under $5000.
lapuwali
QUOTE (Jake Raby @ Jan 4 2006, 07:46 PM)
Exactly....

Thats really apparent on engines that make all their power below and will not even rev 5,000 RPM- Like my Pinzgauer engine...

My whole point is that HP is way over rated and generic for street cars that spend their at midrange RPM.

I give up... dry.gif
Jake Raby
QUOTE (grantsfo @ Jan 4 2006, 08:15 PM)
QUOTE (Jake Raby @ Jan 4 2006, 08:09 PM)
Narrow minds all think the same.

Jake when you can sell a 150 hp engine for around $7500 my mind will open to the incredible possibilities offered by your genious with T4 engines. My sense is your production volumes will never get you to that price point. So I'd rather pick up a used 6 with a warranty for under $5000.

I was just being a smartass...
Overlook me. boldblue.gif
Bleyseng
Isn't a 2270 kit in that ballpark?


Me, I am trying to get a 80hp 1.7l rebuild for Blair's 72 on a small budget.......but he has eyes for my 2056 engine. flipa.gif
TeamAxisRacing
ph34r.gif huh what 2056? mmm driving-girl.gif
Gearhead1432
The stock Djet 1.7 makes 80hp DIN... wink.gif

Unless it happens to be a Kalifornia model icon8.gif
grantsfo
QUOTE (Jake Raby @ Jan 4 2006, 08:35 PM)
QUOTE (grantsfo @ Jan 4 2006, 08:15 PM)
QUOTE (Jake Raby @ Jan 4 2006, 08:09 PM)
Narrow minds all think the same.

Jake when you can sell a 150 hp engine for around $7500 my mind will open to the incredible possibilities offered by your genious with T4 engines. My sense is your production volumes will never get you to that price point. So I'd rather pick up a used 6 with a warranty for under $5000.

I was just being a smartass...
Overlook me. boldblue.gif

..I'm not a smart ass. wink.gif
Bleyseng
Yes, thats what we are putting together, a stock "W" code engine. The one with domed 90mm pistons and little valve heads.

I can see a turbo in the future..... popcorn[1].gif
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