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?

L79racer · 07-14-2013, 09:48 PM

Quote:

Originally Posted by james schaechter

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?

Why doesnt my shift point match gear selection? I used to run a Nash 5 speed then switch to a glide. Its been 9.92 at over 134 mph at 2900lbs.. With that Mph and a 29" tire it was going through the traps around 7000 plus or minus a few rpms. I dont want to be going through the traps over 7200.

james schaechter · 07-23-2013, 09:35 AM

The short tire at 134 answers the question. The detail in the last post is helpful. Definately not set up for best e t so that makes it pretty easy to choose. It depends on if you have any future plans to change the car. Sounds like the car has more than enough power to run 3.08 or even like a 2.93 or so. Only you have enough info to decide, but it would be good to discuss the ratios with Scott at Jerico so you don't pick something odd that is hard to change later. Good Luck!

jscamaro1 · 07-24-2013, 07:01 PM

Seems to me you would be going the wrong way with the first gear. With that rear gear and small tire I would want a 3.19 way before a 2.93 or 3.08. Clutch setup might be tricky with not much ratio in the trans or rear end.

Ever call G-force?

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: 1,928 Likes: 1,072 Liked 1,212 Times in 249 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 Posts: 574 Likes: 6 Liked 44 Times in 22 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: 1,928 Likes: 1,072 Liked 1,212 Times in 249 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

07-23-2013, 09:35 AM	#9
james schaechter VIP Member Join Date: Dec 2004 Location: Cumming GA Posts: 1,928 Likes: 1,072 Liked 1,212 Times in 249 Posts	Re: Jerico 4 spd ratio? The short tire at 134 answers the question. The detail in the last post is helpful. Definately not set up for best e t so that makes it pretty easy to choose. It depends on if you have any future plans to change the car. Sounds like the car has more than enough power to run 3.08 or even like a 2.93 or so. Only you have enough info to decide, but it would be good to discuss the ratios with Scott at Jerico so you don't pick something odd that is hard to change later. Good Luck! __________________ James Schaechter 3163 STK

07-24-2013, 07:01 PM	#10
jscamaro1 Junior Member Join Date: Mar 2011 Posts: 13 Likes: 0 Liked 3 Times in 1 Post	Re: Jerico 4 spd ratio? Seems to me you would be going the wrong way with the first gear. With that rear gear and small tire I would want a 3.19 way before a 2.93 or 3.08. Clutch setup might be tricky with not much ratio in the trans or rear end. Ever call G-force?