Gearing for swap.
Gearing for swap. Starting my JY 6.0 turbo build and have a question about gearing for a turbo engine.
Plan on running a 4l80e behind the engine. I figure 8-12# boost is likely to be it.
The swap is going in a '85 Chevy C-10 SWB which is roughly 3700-3800 pounds. Primarily a driver but I'm sure it will see the track plenty of times a year (NED is 15 minutes away) so I'll have the rear set up well the track.
What gear will really be a good street/strip gear for a heavy turbo? I really want to have good highway manners at 75-80mph but I also plan to tape the time slip to the glove box.
I might even want to tow my drag car ('64 Nova) to the track with my'85.
Plan on running a 4l80e behind the engine. I figure 8-12# boost is likely to be it.
The swap is going in a '85 Chevy C-10 SWB which is roughly 3700-3800 pounds. Primarily a driver but I'm sure it will see the track plenty of times a year (NED is 15 minutes away) so I'll have the rear set up well the track.
What gear will really be a good street/strip gear for a heavy turbo? I really want to have good highway manners at 75-80mph but I also plan to tape the time slip to the glove box.
I might even want to tow my drag car ('64 Nova) to the track with my'85.
A 3.50 gear would cruise nice, give you a decent slr and should have okay rpm across the stripe. Good compromising gear imo. But being a ten bolt I think you're limited to 3.42 or 3.73,
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If it were me I would calculate final drive ratio with a few different rear end ratios, but make the priority for driveability for the street when selecting the rearend ratio.
For the track I would use a taller tire\wheel combination to change final drive ratio. You probably don't want to drive daily on drag radials. Should be able to get a pretty tall tire to fit since it is a truck.
A low or high stall will also make a difference when driving on the street compared to the drag strip.
Just me, but really annoying after awhile to be crusing the blvd's at 45 mph with a 4000 stall and it makes your gas mileage suck too.
For the track I would use a taller tire\wheel combination to change final drive ratio. You probably don't want to drive daily on drag radials. Should be able to get a pretty tall tire to fit since it is a truck.
A low or high stall will also make a difference when driving on the street compared to the drag strip.
Just me, but really annoying after awhile to be crusing the blvd's at 45 mph with a 4000 stall and it makes your gas mileage suck too.
Right,
I'll run somewhere in a 30" for street use and a 28x10.5 bias at the track.
New to turbos so not sure if it's about getting out of the hole or big end.... thinking more about big end. If I can get out hard enough on a 3.42 that would be cool as that is a 2100ish RPM at 80mph. I expect converter slip will increase rpm a bit from there unless I get a lockup unit.
Converter is another question, I'm thinking 3000 stall from freakshow. That will allow it to spool up a bit and will have decent street manners. Is 3000 about right? And should o lockup?? Haven't called freak show yet so I really don't know the cost diff yet. If I do get a lockup I'll switch it off at the track.
I guess I should mention I'll be running the Trickflow LS cam that most are running too but will stay with stock heads.
The 10 bolt will be fine once I'm done with it. I don't expect it to 60ft any harder than 1.6-1.5.
I'll run somewhere in a 30" for street use and a 28x10.5 bias at the track.
New to turbos so not sure if it's about getting out of the hole or big end.... thinking more about big end. If I can get out hard enough on a 3.42 that would be cool as that is a 2100ish RPM at 80mph. I expect converter slip will increase rpm a bit from there unless I get a lockup unit.
Converter is another question, I'm thinking 3000 stall from freakshow. That will allow it to spool up a bit and will have decent street manners. Is 3000 about right? And should o lockup?? Haven't called freak show yet so I really don't know the cost diff yet. If I do get a lockup I'll switch it off at the track.
I guess I should mention I'll be running the Trickflow LS cam that most are running too but will stay with stock heads.
The 10 bolt will be fine once I'm done with it. I don't expect it to 60ft any harder than 1.6-1.5.
