Jerico 4 spd ratio?

L79racer · 07-12-2013, 07:04 PM

Whats a good ratio for a 550 hp motor with 4.56 rear gears at 3000lbs? I know its a little vague.

Dinsdale · 07-13-2013, 12:10 AM

You need to call Jerico and be a little (actually a lot) less vague. Any other advice at this point is pure speculation and pretty much useless.

tj310 · 07-13-2013, 08:46 AM

30 x 9 tires ? smallblock ? we switched from a 3.25 first with a 5.57 rear to 2.75 x 6.0 ,similar results . If I were buying new 3.08 ---Trevor

james schaechter · 07-13-2013, 09:56 AM

The standard Jerico ratio that you see is typically a 3.19 low. If you don't have adequate hook, maybe 3.08 or even less, but only if you are working around less then ideal set up like a street strip car or small tire combo that does not work well. Clutch plays a big role. 4.56? Low rpm engine or street strip? If you can't hook the low gear and adapt the ratios to compensate, get a gear set that is easier to upgrade. Make sure the forst gear set is 33/15 and work with Scott at Jerico to pick the rest. If you plan on ramping up the car to handle the more traditional race ratios, it makes a difference. If you do it right, you can then change only main drive gears to go to a 3.19. If you pick some weird ones, it gets expensive because you have to choose a whole set.

Run to Rund · 07-13-2013, 10:44 AM

After a discussion with Scott on my fairly similar combination, I got 3.08, 1.93, 1.34 iirc.

L79racer · 07-14-2013, 11:41 AM

Quote:

Originally Posted by james schaechter

The standard Jerico ratio that you see is typically a 3.19 low. If you don't have adequate hook, maybe 3.08 or even less, but only if you are working around less then ideal set up like a street strip car or small tire combo that does not work well. Clutch plays a big role. 4.56? Low rpm engine or street strip? If you can't hook the low gear and adapt the ratios to compensate, get a gear set that is easier to upgrade. Make sure the forst gear set is 33/15 and work with Scott at Jerico to pick the rest. If you plan on ramping up the car to handle the more traditional race ratios, it makes a difference. If you do it right, you can then change only main drive gears to go to a 3.19. If you pick some weird ones, it gets expensive because you have to choose a whole set.

Thanks for the replies, Its a 383 small block chevy. I will be shifting at 7200 and should be going through the traps about the same. Probably a 29x9 tire. Once its done If needed might go to 4.88. It will be a 4 link so hooking should not be a problem. Clutch will be a ram adjustable. I see a lot have the 3.08 1.93 1.34. If you go to a 3.19 what do you bring second and third to?

james schaechter · 07-14-2013, 09:10 PM

http://www.jericoperformance.com/charts.htm

This lists the chart on gears. How much power and how much weight. What RPM do you plan on finishing at?

The reason I ask is that your shift rpm doesn't seem to match your gear selection. Not saying you are wrong. Just need more info. If youhave the power and torque to run a lot of mph, then maybe you need a 2.90 something first gear. If not and you can't handle the rpm on the other end, maybe reconsider the shift rpm also?

07-12-2013, 07:04 PM	#1
L79racer Member Join Date: Jan 2005 Location: North Massapequa, NY Posts: 218 Likes: 0 Liked 0 Times in 0 Posts	Jerico 4 spd ratio? Whats a good ratio for a 550 hp motor with 4.56 rear gears at 3000lbs? I know its a little vague.

07-13-2013, 12:10 AM	#2
Dinsdale Member Join Date: Oct 2004 Location: Canada Posts: 313 Likes: 0 Liked 6 Times in 2 Posts	Re: Jerico 4 spd ratio? You need to call Jerico and be a little (actually a lot) less vague. Any other advice at this point is pure speculation and pretty much useless. __________________ Dale Posnick

07-13-2013, 08:46 AM	#3
tj310 Member Join Date: Sep 2009 Location: Dresden On. Canada Posts: 460 Likes: 0 Liked 0 Times in 0 Posts	Re: Jerico 4 spd ratio? 30 x 9 tires ? smallblock ? we switched from a 3.25 first with a 5.57 rear to 2.75 x 6.0 ,similar results . If I were buying new 3.08 ---Trevor

07-13-2013, 09:56 AM	#4
james schaechter VIP Member Join Date: Dec 2004 Location: Cumming GA Posts: 1,985 Likes: 1,277 Liked 1,424 Times in 294 Posts	Re: Jerico 4 spd ratio? The standard Jerico ratio that you see is typically a 3.19 low. If you don't have adequate hook, maybe 3.08 or even less, but only if you are working around less then ideal set up like a street strip car or small tire combo that does not work well. Clutch plays a big role. 4.56? Low rpm engine or street strip? If you can't hook the low gear and adapt the ratios to compensate, get a gear set that is easier to upgrade. Make sure the forst gear set is 33/15 and work with Scott at Jerico to pick the rest. If you plan on ramping up the car to handle the more traditional race ratios, it makes a difference. If you do it right, you can then change only main drive gears to go to a 3.19. If you pick some weird ones, it gets expensive because you have to choose a whole set. __________________ James Schaechter 3163 STK

07-13-2013, 10:44 AM	#5
Run to Rund Senior Member Join Date: Sep 2007 Location: Henderson, NV Posts: 583 Likes: 8 Liked 54 Times in 27 Posts	Re: Jerico 4 spd ratio? After a discussion with Scott on my fairly similar combination, I got 3.08, 1.93, 1.34 iirc.

07-14-2013, 09:10 PM	#7
james schaechter VIP Member Join Date: Dec 2004 Location: Cumming GA Posts: 1,985 Likes: 1,277 Liked 1,424 Times in 294 Posts	Re: Jerico 4 spd ratio? http://www.jericoperformance.com/charts.htm This lists the chart on gears. How much power and how much weight. What RPM do you plan on finishing at? The reason I ask is that your shift rpm doesn't seem to match your gear selection. Not saying you are wrong. Just need more info. If youhave the power and torque to run a lot of mph, then maybe you need a 2.90 something first gear. If not and you can't handle the rpm on the other end, maybe reconsider the shift rpm also? __________________ James Schaechter 3163 STK