RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   Race Car Tech (https://www.rx7club.com/race-car-tech-103/)
-   -   13b dry supm std style drive ratio ? (https://www.rx7club.com/race-car-tech-103/13b-dry-supm-std-style-drive-ratio-868878/)

MRJACK$ON 10-16-09 02:14 AM

13b dry supm std style drive ratio ?
 
Hello all, does anyony know whats the ideal sproket ratio(size,tooth count) for the pump & the motor for a external 3 stage pump,in a road race setting lookin to turn 8500-9000 RPM maximun. LMK THANKS:):)

Chaotic_FC 10-16-09 02:54 PM

very good question!! :lol: i need to know this myself.

MRJACK$ON 10-18-09 01:20 PM

^^^ really what are you building maybe we can brainstorm ideas. Im using a weaver brothers 3 stage pump,a modified mazda race pan/plate,& a 5gal tank, all -12 lines. I fabbed up a mount for the pump using the stud & holes for where the AC COMP. used to go.

EProdRx7 10-18-09 09:20 PM

I think you need to get in touch with the pump manufacturer and see what the recommended RPM range is. Then you'll need to size the pulleys accordingly. The one on my Sports racer runs off the water pump drive on a Kawasaki ZX10R. I believe it is a 1:1 drive and the motor runs 13000 rpm all day.

Chaotic_FC 10-19-09 11:41 AM


Originally Posted by MRJACK$ON (Post 9569302)
^^^ really what are you building maybe we can brainstorm ideas. Im using a weaver brothers 3 stage pump,a modified mazda race pan/plate,& a 5gal tank, all -12 lines. I fabbed up a mount for the pump using the stud & holes for where the AC COMP. used to go.

EProdrx7 is defiantly right about us needing to check with the manufacturer.

I'm using a 3 stage pump as well, and a custom 3/4" thick aluminum oil "plate". you can see it all if you check my build thread. (link in sig)

are you taking the measures to drop your engine down in the car now that the oil pan is gone?

jgrewe 10-19-09 12:05 PM

The only set up I've had my hands on was thrown together from a bunch of parts from an ARCA car.
We weren't allowed a 'dry' sump so we left the stock pan and pump on the car for scavenge. IIRC the pump ran about 1/3 engine speed, I can check the stuff today and count teeth. The pumps have different springs to set pressure ranges so as long as you get the volume you want the pressure is no problem. The car had a guage that only went to about 100psi at first and it spent its time pegged at 100 at anything above 4000rpm. We were thinking, well, pressure isn't an issue... We ended up putting a new guage in it with a higher range so we could set the pressure around 115-120psi. The first session with the new guage and hot oil the oil was running 180psi at top rpm! The next session with a new spring in the pump we had it down where we wanted it and probably picked up a few HP.

Hey Chaotic, where exactly in Fl are you? I'm in St Pete Bch.

Chaotic_FC 10-19-09 12:14 PM

fort lauderdale!

scathcart 10-22-09 07:06 PM

50% shaft speed, 1.100 pump stage, bypassed at 120 psi, wide clearances, 13B maintained pressure to 10K rpm.

Similar engine, .750 pump stage, driven at 57% shaft speed, maintained pressure to 10K.

I would go with 50% if your pump stage is .875" or wider.


All times are GMT -5. The time now is 07:50 AM.


© 2024 MH Sub I, LLC dba Internet Brands