RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   What sort of drivetrain loss is there on an FC? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/what-sort-drivetrain-loss-there-fc-385659/)

bennettaru 01-14-05 05:52 AM

What sort of drivetrain loss is there on an FC?
 
Can anyone give me a rough percentage of drivetrain loss in power from the fly to the wheels?

bennettaru 01-14-05 06:14 AM

never mind, i think it's around 30%

CyborgRyu 01-14-05 06:45 AM

lol 30%. our cars isn't fwd or awd.

drivetrain loss on rwd is very minimal. I believe closer to the range of 15%

patman 01-14-05 07:32 AM

15-20%

Crionics 01-14-05 10:12 AM


Originally Posted by CyborgRyu
lol 30%. our cars isn't fwd or awd.

drivetrain loss on rwd is very minimal. I believe closer to the range of 15%

Why would it be less than fwd?

CyborgRyu 01-14-05 11:00 AM

hm..it was early when i typed that. well i think the fwd has a even less power loss, but still do as well as a RWD since when you launch a car, the weight shifts to the rear, giving it more traction than a FWD would. hence in a way, you lose some power in a FWD

1987RX7guy 01-14-05 11:03 AM

actually FWD launch is faster for the launch than RWD. Once weight transfer takes place RWD takes the front.

bennettaru 01-14-05 11:20 AM

FWD Definetly has LESS loss than RWD, anyways, i just got the info from autospeed


It's widely generalised that there's a 30% power loss through a RWD's drivetrain, while a FWD loses only 20%.

vaughnc 01-14-05 03:56 PM

~15-17% NA
~17-19% Turbo II (hot dyno intercooler & beefier drivetrain).

RETed 01-14-05 05:08 PM

15% on average is fine.
20% is too high.
I've seen an FD (similar drivetrain) put down 12.5% with all Redline fluids.


-Ted

Snrub 01-15-05 12:15 PM


Originally Posted by 1987RX7guy
actually FWD launch is faster for the launch than RWD. Once weight transfer takes place RWD takes the front.

:confused: Why do you say that, are you assuming there's more weight over the front wheels in a static situation and you're refering a split second before the car has moved appreciably?

RotaryEvolution 01-15-05 12:31 PM

because a RWD has a rubber band effect, it takes a moment for the weight to shift rearward before the car begins to move, in a FWD the tires begin to grab instantaneously but lose traction easier because the weight is shifted to the rear.

dag 01-15-05 01:41 PM


Originally Posted by Karack
because a RWD has a rubber band effect, it takes a moment for the weight to shift rearward before the car begins to move, in a FWD the tires begin to grab instantaneously but lose traction easier because the weight is shifted to the rear.

Um. No. The weight shifts rearward when a car is launched no matter what. The difference between the two is that while a FWD car has it's traction pulled up by this weight transition, a RWD cars traction is forced down towards the blacktop. So no, given the exact same car one being FWD and one being RWD, the RWD car will be capable of a lower 60' time.

The Griffin 01-15-05 02:00 PM

I'm under the impression that drivetrain loss is a function of hp.So it could be something like 15% in a lower hp car and a lessor value in the the same vehicle but putting out twice the hp.Anybody shed some light on this(fact/fiction)?

PureSephiroth 01-15-05 02:29 PM


Originally Posted by dag
Um. No. The weight shifts rearward when a car is launched no matter what. The difference between the two is that while a FWD car has it's traction pulled up by this weight transition, a RWD cars traction is forced down towards the blacktop. So no, given the exact same car one being FWD and one being RWD, the RWD car will be capable of a lower 60' time.

Um. Duh. that's what they're saying. FWD puts power to the wheels faster than RWD because its physically closer to the power plant. The wheels simply can't hook up once the weight begins to shift.

capn 01-15-05 03:41 PM

dont think FWD cars have it so great my caddy has 300 at the crank yet only 220 at the wheels thats a 27% loss. but then again it has one of the strongest automatic transaxles, so it sucks power

dag 01-15-05 11:12 PM


Originally Posted by PureSephiroth
Um. Duh. that's what they're saying. FWD puts power to the wheels faster than RWD because its physically closer to the power plant. The wheels simply can't hook up once the weight begins to shift.


My fault on the misquote I was speaking to this guy:


Originally Posted by 1987rx7guy
actually FWD launch is faster for the launch than RWD. Once weight transfer takes place RWD takes the front.


Mint87RX7 01-15-05 11:17 PM

isnt the topic about hp loss through friction in the drivetrain? what does the weight distribution have to do with it, your going to have the same rwhp whether you get traction or not

flamin-roids 01-15-05 11:21 PM

I think its even worse on automatic transmissions. And FWD is good for the little umph right off the line but thats it. FWD is more efficient however. But RWD is funner and is more practical for racing.


All times are GMT -5. The time now is 06:37 PM.


© 2024 MH Sub I, LLC dba Internet Brands