200 hp club?

[madkaw]

All these HP are great, but the OP was wanting to make the "club" with his L24. This would be something to really brag about. I'm sticking with my 24 until I've exhausted myself trying to make 200 with it. It's probably going to take a bigger cam and the triples to happen

[jackboxxx]

Nice numbers John,

so...from 325 at the engine, to 282 at the wheels is like a 13% drop thru the drivetrain...then with tweaking you got the drop down to ummm less than 10% drop...to the wheels.. I figure with my street car its more like a 20% loss of power? so im probably around 230hp or so sigh...

Horsepower numbers...

My racing 3L made 325 hp on Kinetic/Sunbelt's SAE certified engine dyno. It made those numbers repeatedly on different days. The engine was shipped out here to SoCal and put in my race car. Jim Thompson came out and we spend 1/2 a day verifying the installation at Superior Automotive's chassis dyno in Anaheim. 282hp to the rear wheels is what we measured. We did some tweaks to the install due to some cooling concerns and went back the next day. 294 hp to the wheels with no changes to the tune, fuel, etc. The car did not magically pick up 12 horsepower.

[Oiluj]

Have you dyno'd your Z with measurements to the wheels - just wondering?

Only with my bucket seat, "butt dyno", and it seems quite happy...

I really don't know, but I'd guess-timate I lose something between 15% to 25% through the stock drivetrain. That means between 160 to 180 HP at the rear wheels, (but probably closer to 160). Without putting it on a calibrated dyno, it will remain a mystery...

[Travel'n Man]

My dyno was to the rear wheels -154.11 hp 172.21 torque - I'm sure with very little effort I could increase those numbers, but I'm happy where I am - for street/show what are you going to do with all that HP anyway.........

[jackboxxx]

what are you going to do with all that HP anyway.........

if you have to ask.....

[Diseazd]

There are some super motors and numbers being thrown out, some nice builds, but the thread is about the L24. Nobody builds better motors than Rebello and Coffey......I don't dispute that. All I'm saying is.......does anyone have a street driven Z with an L24 (NA and non turbo) that puts 200 h.p. To the rear wheels that will run on pump gas? I'd love to see how it could be done.......It would amaze me!

[Travel'n Man]

I'm agreeing with Guy - I think nobody has generated 200 RWHP without changing the entire dynamics of the L24 engine.

[steve91tt]

Most of the folks building NA motors for these cars are not worried about keeping the original block. You don't see many high HP L24's because L28's are cheap, available and bolt right in. The extra displacement just makes things easier. John said above that he has seen a 2.4L L6 engine make 208hp on a SAE certified engine dyno running a "stock" cam, SU carbs, headers, and a good ignition. This agrees with what I have read elsewhere and what Dave Rebello also told me about his experience building these motors. If you took that motor and added a decent cam, triples and did some porting I don't see why it wouldn't be over 200HP at the wheels and be quite streetable. 85hp per liter at the wheels is not unreasonable for these motors given the fact that John is making 98hp per liter at the wheels with his L30 race motor.

[30 Ounce]

Displacement is your friend. If your willing to go to a 2.8 or 3.0 liter (still looks like 2.4!!) it would help a lot. And if your talking at the crank that would also help. I did a lot of head work on mine and am at 184hp at the wheels. I'll post a dyno of my 178hp run cause I don't know were the other one is.[ATTACH=CONFIG]49780[/ATTACH]

started with Rebello 3.0 liter bottom end. E88 head ported, chambers welded (custom shape 11.5:1 compression.), steel seats, bigger valve, Isky 490-290 cam, Rebello modified SU carbs, MSA 6-1 header, 2 1/2" exhaust.

Since this dyno I've taken the oil out of the dashpots & did a couple of mods that Dave recommended and retuned. Seems to be a lot more powerful now but dyno needs to confirm this.

This was at 5000 feet elevation and my dyno guy says its not corrected for elevation.

[John Coffey]

Nice numbers John,

so...from 325 at the engine, to 282 at the wheels is like a 13% drop thru the drivetrain...then with tweaking you got the drop down to ummm less than 10% drop...to the wheels..

My point was that we made no change that would have increased the fuel or air used in the engine so the "increase" in horsepower was just an anomaly of the chassis dyno. IMHO, chassis dynos are tuning tools and not to be used to generate bench racing horsepower numbers.

In the past I've had two identical L6 engine built to SCCA ITS specs, one was a L24 and the other was a L28. Same carbs, same cam (stock), same headers, same ignition, etc. Probably as close to same as possible. The L24 engine made more horsepower then the L28 because I could spin it to 7,500 rpm and tune it to take advantage of that rpm. The L28 made more torque and was easier to drive on the street. If I remember correctly, the L24 made 190hp on the engine dyno and the L28 made 181hp on the same dyno.

[coop]

Hey John, earlier this year when I accidentally hit 7500 rpm on my ITS engine, the valves floated and cracked a piston. I only rev to 7200 when shifting from 2nd to 3rd at the start of the race and then 6800 for all the 3rd to 4th shifts because that is where the hp curves cross. The OEM valve springs just aren't up to the task plus the power really drops off above 7000.

My new Rebello engine has made Dave proud. It hit 205.2 hp at 6100 rpm and 196.8 ft-lb of torque at 5000 rpm. This is up from 200.7 hp and 190.7 ft-lb on the previous engine. Dave thinks that maybe his latest piston rings or maybe my newest Stahl stepped header may have made the difference.

So, it is possible to get 200+ hp at the crank with a "fairly" stock L24. All it takes is money and Dave Rebello.

[John Coffey]

That's great! See post #28 above. Sunbelt hit similar numbers a while ago with one of Chet's engines - which won the ARRC twice. It takes a lot of labor to get those numbers with stock parts. Javier hit the 190hp number I mentioned above back in the early 1990s. Here's a video of his 190hp engine in an ITS race back in the day.

Javier's car is the red #35.