| Author |
Message |
John B (John_b)
Junior Member
Username: John_b
Post Number: 78
Registered: 5-2003
| | Posted on Monday, October 20, 2003 - 7:01 am: | |
In my experience drivetrain loss is approximately 15%. I doubt the 360 loses 22%. I dynoed my M5, rated at 396HP and got 335HP at the rear or about 15.5% loss. Incidently I think it should better be expressed as a constant number, not a ratio. I doubt if you modify an engine to put out an extra 100 HP at the crank only 85HP would make it through to the rear wheels. It should simply take a fixed amount of HP to overcome the friction in the transmission and drive train. In this case I would expect higher HP engines to display lower power train losses as a % of their crank HP. |
Jeff Edison (Euro308guy)
Member
Username: Euro308guy
Post Number: 445
Registered: 7-2002
| | Posted on Monday, October 20, 2003 - 6:46 am: | |
To me, the dyno numbers quoted here would seem to be about right. I know that the last time my 348 twin turbo was dyno tested, it came out to exactly 350 whp. When I drove it on club day behind our member's 360, at low rpm's the 360 actually slowly walks away, then under moderate to high boost, the 348TT catches him and given the chance to stay all the way into the throttle, might even pass him.
The numbers would seem to reflect acuracy based on this loose interpretation. |
Mike Winston (Mikew)
Junior Member
Username: Mikew
Post Number: 106
Registered: 10-2003
| | Posted on Monday, October 20, 2003 - 1:58 am: | |
Is there any HP difference between Euro and US 360s? I seem to remember reading that the US version of the Porsche GT2 was down just a few HP from the Euro version which got me wondering if that might account for the 5HP in question on the 360. |
Michael W. (Whimike)
Junior Member
Username: Whimike
Post Number: 78
Registered: 7-2003
| | Posted on Monday, October 20, 2003 - 1:52 am: | |
How does 22% drivetrain loss make sense? In the Porsche world, we use a 15% drivetrain loss when the front wheels are disconnected on a 2-wheel dyno, or 20% if using a 4-wheel dyno. Can the 360 drivetrain be that inefficient?!?
-- Michael |
Thomas I (Wax)
Member
Username: Wax
Post Number: 627
Registered: 7-2003
| | Posted on Monday, October 20, 2003 - 12:38 am: | |
From Ferrari's site - 360 Modena
No. of cylinders 90� V8
Bore & stroke 85x79 mm
3.34x3.11in.
Unit displacement 448.2 cc
27.36 cu. in.
Total displacement 3,586 cc
218.84 cu. in.
Maximum power 294 kW (400 bhp) @ 8,500 rpm
Maximum torque 373 Nm (275.6 lbs/ft) @ 4,750 rpm
|
allan fiedler (Allanlambo)
Intermediate Member
Username: Allanlambo
Post Number: 1386
Registered: 6-2002
| | Posted on Monday, October 20, 2003 - 12:22 am: | |
If a 360 only makes 300-310rwhp, i wonder how well it would fair against a 355 with headers,cat-bypass pipes,exhaust and airfilter upgrade. Ive read that they produce around 330rwhp in this setup.
Actually i think 300-310rwhp seems low. Corvette Z06's may be slightly faster than 360's, but they weigh about the same and produce about 350rwhp, so i think a 360 should do better than 310rwhp. Any ideas? |
Brian Kennedy (Kennedy)
Member
Username: Kennedy
Post Number: 525
Registered: 3-2002
| | Posted on Sunday, October 19, 2003 - 11:50 pm: | |
Actually, I think 22% is the standard assumed loss in the drivetrain... with 400hp that's a whopping 88hp... so 310hp is about right. |
Tim G. (Tim)
Member
Username: Tim
Post Number: 282
Registered: 3-2002
| | Posted on Sunday, October 19, 2003 - 11:24 pm: | |
I think it was about 310. I was shocked that it lost so much through the drivetrain. |
Brian Kennedy (Kennedy)
Member
Username: Kennedy
Post Number: 524
Registered: 3-2002
| | Posted on Sunday, October 19, 2003 - 11:07 pm: | |
300 to the rear wheels seems a bit low... shouldn't it be 310-315 or so? How hot was it at the dyno? |
Tim G. (Tim)
Member
Username: Tim
Post Number: 280
Registered: 3-2002
| | Posted on Sunday, October 19, 2003 - 10:54 pm: | |
I think ferrari says 400. I just had a 360 on the dyno and it is only 300hp to the wheels. |
Gary Brauch (Gary_brauch)
New member
Username: Gary_brauch
Post Number: 28
Registered: 10-2003
| | Posted on Sunday, October 19, 2003 - 10:33 pm: | |
I've heard great things about the Radical, if I were looking for a track-only vehicle that would be my first choice. What SCCA class did you compete in? I was in FF '73 - '78 and SSB RX7 '79 - '81 (I know, that makes me an old fart!) |
Bob McGrew (Bob_mcgrew)
New member
Username: Bob_mcgrew
Post Number: 4
Registered: 6-2003
| | Posted on Sunday, October 19, 2003 - 10:23 pm: | |
Mill Valley Gary is a good friend, Raded with him in Scca many years before moving to Charlotte,Nc. I'll tell him That I met "yall" Don't know about the 5 horsepower Question, But, Our Radical with 1300cc is way faster |
Gary Brauch (Gary_brauch)
New member
Username: Gary_brauch
Post Number: 27
Registered: 10-2003
| | Posted on Sunday, October 19, 2003 - 10:17 pm: | |
Amazingly enough (given how unusual the name is), no, although we both raced SCCA in the same time frame and I know him slightly. I'm in the Palo Alto area. |
Bob McGrew (Bob_mcgrew)
New member
Username: Bob_mcgrew
Post Number: 3
Registered: 6-2003
| | Posted on Sunday, October 19, 2003 - 10:13 pm: | |
Is this the Gary Brauch that lives in Mill Valley, Ca? |
Gary Brauch (Gary_brauch)
New member
Username: Gary_brauch
Post Number: 25
Registered: 10-2003
| | Posted on Sunday, October 19, 2003 - 10:02 pm: | |
Somebody help me break the code. Some magazines report 395, others 400. Ferrari says 400. I know, 5hp is hardly worth mentioning, but when it is the difference between 395 and 400 it seems much larger... |