How much HP coming from a 2.4 with 9.8:1?

[POORSH]

Just got a replica with a 2.4, E cams and 32mm Webers and 9.8:1 compression. I was told the engine makes around 200hp, but I doubt it. It doesn't feel as strong as my 73.5T. But then again, I think the 73.5T has been worked on by the previous owner (feels very strong for a 2.4).
The question is, how much power do you guys think is coming from the 2.4 with the E cams? What is the max power you can get out from a setup like that? Thanks.

[lateapex911]

I shouldn't do this, as it's just a guess, but...

Depending on the carb tune, the ignition tune, the exhaust setup, and other little things, I'd bet that getting 175 at the flywheel would be all you could hope for.

At the hubs, on a Dynapak chassis dyno, I'd expect to see no more than 150 ....

[kucharskimb]

2.2 E stroker HP output

we dyno'ed my 2.2E stroked to a 2.4 after the rebuild. put out 172 at the wheels. i dyno'ed it again last year. the second time it was running a little lean, but still put out 165 at the wheels.

if you use the 15% rule...

165 x 1.15 = 190
172 x 1.15 = 198

so, yes, your estimates are a good ballpark.

mine is a 2.2E stroked to 2.4. Crane ignition. SSi's. Modified stock muffler. Webers.

you should have a really nice motor.

[jstobo]

Well the 72-73 E's 2.4 with 8:1 compression and MFI were rated at 165HP DIN. Only difference to your motor appears to compression ratio and Webers. Probably higher than stock but I doubt 35HP more. But who cares. These early cares are not about HP but about fun to drive. Get your car on a track and you will see what I mean.

[Tyson Schmidt]

I had a 2.4 with mod-Solex cams (re-ground E-cams) and similar compression with MFI that made 143hp at the wheels. That worked out to roughly 186 at the crank.

Webers are about 10hp less than MFI, but it all depends on the tuning. A poorly tuned MFI will make less power than well-tuned Webers, and vice-versa.

My MFI pump was tired, and probably could have made another 10-15hp if it were fresh.

Also, a factory-style sport muffler is good for 15HP over a stock early muffler.

[lateapex911]

Also, keep in mind that the dyno business is less than dependable, and some dynos are always "different" than others...In the car racing rules game, we have a saying, "Is that DynoXXXX hp or real hp?"

Tyson, how did your numbers get from 143 at the wheels to 186 crank? Thats a big adjustment...over 30% I think...?

[kucharskimb]

i should mention that the two dyno runs mentioned were on two different dyno's, in two different states, about 2 years apart, under different ambient temperatures. altitudes were about the same.

but it doesn't really matter, now, does it.... every time i bring this dyno sheet up, the guy with the 3.0 that puts out 2 hp less tells me my numbers are bogus. and then the "DIN" word comes out...

DIN = .99 x SAE => a negligible conversion.

enjoy your engine.

[POORSH]

Thanks for the info. I guess I was just a little disappointed that the car is not as fast as it looks. I would not have a problem swapping the engine/trans(901) for a bigger motor/trans, but it hurts to see the current setup go to waste since it only has 1k miles since engine rebuilt.

[haycait911]

don't feel bad, my 2.7 with carrera p/c's, e cams, and webers dynoed 155 hp and 165 ft/lbs at the wheels. I weigh just under 2400 lbs and this car is very quick. numbers don't tell everything. my old 914 with 94 din hp was the most fun I've ever had and would show up a lot of cars that on paper should have eaten it alive. forget adding power, lose weight. better performance AND better handling. Don.

[POORSH]

Don,
I don't think I can lose any more weight on the car. The car is basically stripped to metal. The interior is competely gutted out, no dash, no panels, no head liner, etc. I think it weighs about 2100lbs. I will get it out on the track one of these days.

[haycait911]

it's more of a philosophy than anything, if you're at 2100 lbs your car should go like h*ll! don't worry about #'s so much and just enjoy the ride. the guy who dyno'd my car was very impressed even if I wasn't. he explained to me that most cars don't make the numbers their owners would like when dyno'd. it's more about the hp/torque curve and driveability. hp #'s is a muscle car game, we should be above that. Don.
ps. oops, even I inflated my #'s.

[Tyson Schmidt]

Originally posted by lateapex911

Tyson, how did your numbers get from 143 at the wheels to 186 crank? Thats a big adjustment...over 30% I think...?

Hmmm, might be my bad memory. I remember for sure that we worked it out to be 186 flywheel assuming 15% loss.

[arrivederci]

Not sure if this is any help, but my '72 came with a warmed over T motor, apparently 2.2S Ps & Cs (haven't torn it down to verify anything). That is supposed to be in the neighborhood of 9.8:1, some say it could be more. My dyno run put it right in the neighborhood of the numbers others are posting - 145 rwhp. That's with MFI and verified T cams. It is a pretty stout motor for what it is. Notice how flat the torque curve is.

[Tyson Schmidt]

Here's the link to my dyno chart. Mine is the first one. it made 158 at the wheels.


Reseda Dyno Day - Results

[Jeff Higgins]

It's all too easy to get wrapped up in horsepower numbers, but that is not what the early 911's are all about. My dead stock 2.4 T motor makes similar power to everyone else's that has chimed in; about 136 RWHP and 143 ft/lbs of torque. Hardly impressive by any measure.

It's performance belies those numbers, however. At just about 2200 pounds, it has no trouble whatsoever in keeping up with, or more often running away from, SC's and Carreras. It won't beat any of them in a drag race, but under braking and through the corners it really shines.

And it's just so damn much fun to drive; that's all I care about. I could have spent half the money and effort to go twice as fast. That's not what these cars are about.