Idk if this has been answered before, I couldn't find anything. I'm going to build a awd Civic with CR-V parts but I want to boost it to 500hp(on my b20) and I was wondering how much hp and tq I can make before I need to upgrade parts? I want to start with 300 while it's still my daily and fwd but when it's a weekend/track car I want to do 500hp with the awd system.

 

i'm interested to here from people in the know as well. 500 hp on stock anything seems like a recipe for disaster, but i really have no idea.

 

let's start with the fact that a brand new crv made 140hp. you are using used parts and more than doubling that power and tq. what do you think?

 

my thoughts too.

the torque is the critical item to consider. general simplification- horsepower makes heat, torque breaks things. So original was about 130 lb-ft peak at the crank. a five second search of dyno graphs for 300 hp B-series shows about 250 lb-ft peak. it's probably reasonable to assume that there is a safety factor of 2 (200%) in the original design of the AWD system. So a 300hp B-series may be ok... but only just. and will certainly wear more quickly.

 

also depends on what its being used for, but its probably the usual drag race down the strip

 

It'll be my track car. Not drag racing.

 

Thanks that's really helpful.

 

Your weak point is going to be the viscous coupling for the rear diff. IF you could adjust the preload on those clutches, you could theoretically increase it's ability to handle more power. If you can't, you'll probably just burn the unit out and be left with lower to the driveshaft that never reaches the rear wheels.

Could an S2K rear end be put into a CRV?

 

I've heard of people putting a wagovan viscous coupler and rear end in insted of the crv. Does anyone know anything about that.

 

For what purpose?

 

It's supposed to be stronger than the crv vicous coupler and rear diff. I'm going to be making about 300 whp

 

The reason ppl use the wagovan is for the full time AWD. The CRV is not full time AWD.

 

Does anyone know what years and models people use the wagovan viscous coupler and rear diff from?

 

 

I don't know if they're stock drivetrains, but there is a 700hp one and a 1300hp one.

https://lmgtfy.com/?q=turbo+awd+civic

 

 

when I went looking to see if some sort of clutch adjustment was feasible I discovered some misconceptions I had that we seem to share.

the early CR-V AWD systems don't have a viscous coupling but a "dual pump" mechanism at the input to the rear diff. The PTO from the transaxle case is driven by the front differential carrier so essentially if the front wheels are moving the "prop shaft" is spinning. the prop shaft drives the front pump in the rear diff. the rear wheels drive the rear pump as they free spin. when the two pumps are spinning at the same speed... nothing happens. when the front pump spins faster than the rear (when the front wheels are slipping) more pressure is created by the front than the rear. the difference in pressure triggers an internal valve and that sends fluid to the clutch pack driving the rear wheels. that said, the OP can run any power level he wants because the back won't be doing anything unless he tries to do a burnout.

but I think it may have potential for "hacking" to operate as desired. if the rear pump were disabled or it's output redirected/rerouted the effect would be the same as a slippage situation. this would drive the rear all the time. for stability during braking, pressure to the clutches should be bleed/diverted back to the sump. this could be done with a solenoid valve triggered by the brake switch. the electrical circuit for the solenoid could also be used to enable/disable rear drive with a relay and switch on the dash. or go even more advanced and have the valve triggered above a certain speed... something like that.

there are two ring gears on the differential carrier in the transaxle. the additional one is what drives the PTO for the rear, but it's a different ratio- it's geared UP. that ratio plus (or multiplied by... for the math nerds) the rear diff ratio is the actual drive ratio for the rear. if an S2000 rear end, or anything with traditional gearing were to be used, this PTO ratio would need to be changed to match. tall order!

 

Oh, and here's a good thread with lots of pictures

AWD CRX del Sol - CRV driveline swap

 

I wonder where that del sol is now.