Rear gear ratio on spray
04-07-2009, 07:57 PM
#1
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Rear gear ratio on spray Someone may be able to help, Building a f-body with a Texas Speed 427LSX, TH350 w/Tranny brake, 28" rear tire, going to spray 300 Direct port, currently has a Moser 12bolt with 4.10 gears, all the suspnsion goodies, what gear are you N20s guys running or recomend with a set up like this?
04-08-2009, 01:45 PM
#2
With the power I would expect that you are going to make, 150 mph trap speeds should be well within your reach if not exceeded.
That being said, a 28 inch tire and a 4.10 gear probably won't get you there. You'll probably need to swap in a set of 3.90's at a bare minimum, probably 3.73's. Or, go to a 29.5 or 30 inch tire, if you can get them under the car.
You didn't mention if the motor is a solid roller or hydraulic motor, I'm assuming it's hydraulic and you plan to spin it to 7200 to 7500, if you're going solid roller and will spin it to 8500 then you're probably o.k. with the 4.10 gearing.
Honestly, I would not just start out with a 300 hit on a new setup, I'd probably get the kit jetted to somewhere around a 24 or 26 nitrous jet and get the tuneup right before you start trying to hit it harder (300 hit being about a 32 jet, at least how we figure it)
Try the car with the 4.10 gearing with the smaller jets, see where you're trapping mph and rpm wise at that power level, see what the converter slippage and whatnot is, plus this will give you a chance to get the car sorted out some too.
Once you have it running right (that jet should get you to a single digit pass) you'll know what you need gearing wise to get thru in your rpm range.
That being said, a 28 inch tire and a 4.10 gear probably won't get you there. You'll probably need to swap in a set of 3.90's at a bare minimum, probably 3.73's. Or, go to a 29.5 or 30 inch tire, if you can get them under the car.
You didn't mention if the motor is a solid roller or hydraulic motor, I'm assuming it's hydraulic and you plan to spin it to 7200 to 7500, if you're going solid roller and will spin it to 8500 then you're probably o.k. with the 4.10 gearing.
Honestly, I would not just start out with a 300 hit on a new setup, I'd probably get the kit jetted to somewhere around a 24 or 26 nitrous jet and get the tuneup right before you start trying to hit it harder (300 hit being about a 32 jet, at least how we figure it)
Try the car with the 4.10 gearing with the smaller jets, see where you're trapping mph and rpm wise at that power level, see what the converter slippage and whatnot is, plus this will give you a chance to get the car sorted out some too.
Once you have it running right (that jet should get you to a single digit pass) you'll know what you need gearing wise to get thru in your rpm range.
04-09-2009, 06:08 AM
#5
Chance converter is a killer piece for sure, if you're in the market for a converter I'd try getting in touch with lenny @ ultimate converter concepts.. that's who built the converter that's in my car and they do all of eastside's race car converters. Pricing is good and they've been solid performers for us.
