750 horsepower capable 4L80e transmission
This is my base 750 hp “recipe.” This is the platform from which all transmission builds take form. I use this recipe in almost all of my 80e rebuilds. I personally have taken it to 750 wheel hp and use this exact build (with addition of a transbrake) in my (former, now sold) street/strip turbo LS G body that run 9.9x ET traps 140+ mph at Portland International Raceway. Every unit I build gets a 1 year warranty from date of purchase on component quality and workmanship.
The pump pressure regulator valve and spring are modified for more line pressure and correspondingly, modifications are needed to prevent issues from this. The pump body is drilled for a "line to lube" orifice to prevent excess charge pressure in the torque converter. The front seal exhaust port is enlarged to prevent blowing oil past the front seal.
With this increase in fluid flow and line pressure we can address some of the issues the 80e sees in high power, high load applications.
Increased lube orifice size to the 4th gear planetary gears.
Increased lube orifice size to the sun shaft.
The direct clutch is dual fed, meaning the direct clutch apply piston has more surface area for the fluid to act on. The drum is also drilled for faster fluid exhaust and clutch release.
I prefer green Borg HE frictions for fast, firm clutch apply. Forward and intermediate clutch packs have a HD wave/cushion plate for less shock loading of the sprags and rollers. End clearance on all clutch packs was adjusted to nominal specs.
A heavy duty spring pack, retainer plate and case snap ring is added to the intermediate clutch pack and clutch apply piston.
The 2-3, 3-4 accumulator is deleted. This decreases apply times and increases pressure for those gear changes. It also reduces the chance of any "cross-feeding" in the fluid circuits in that area of the valve body. The valve body itself is disassembled, cleaned and vacuum checked. The valve body separator plate is drilled to enlarge the orifices on all forward gear changes.
It has mild shifts at part throttle, and line pressures can still be tuned via HP tuners/Holley etc.
This recipe also features a rollerized output shaft. I replace the selective washer and thrust bushing with a roller-type needle bearing. This reduces drag. I also rollerize the forward clutch hub to direct drum now as well.
Core exchange fee is $600 for '99+ cases, Call for 91-98 case prices. I have cores on hand and am happy to build your unit with my stock, but charge a market-rate core exchange fee.
Please call 503 560 1852 to discuss custom builds, transbrake options (manual and automatic) and SFI bell/aftermarket cases
*for the immediate future I will not be processing deposits and build payments through squarespace. Contact me at douglassproston@gmail.com and I will email you a paypal invoice. Venmo, Cash or Check are accepted if you wish to avoid the 3.5% electronic payment processing fee.
the reason is squarespace is charging an additional fee on top of the paypal fee with the results totaling almost $100 in fees per $1000, which is unsustainable.
This is my base 750 hp “recipe.” This is the platform from which all transmission builds take form. I use this recipe in almost all of my 80e rebuilds. I personally have taken it to 750 wheel hp and use this exact build (with addition of a transbrake) in my (former, now sold) street/strip turbo LS G body that run 9.9x ET traps 140+ mph at Portland International Raceway. Every unit I build gets a 1 year warranty from date of purchase on component quality and workmanship.
The pump pressure regulator valve and spring are modified for more line pressure and correspondingly, modifications are needed to prevent issues from this. The pump body is drilled for a "line to lube" orifice to prevent excess charge pressure in the torque converter. The front seal exhaust port is enlarged to prevent blowing oil past the front seal.
With this increase in fluid flow and line pressure we can address some of the issues the 80e sees in high power, high load applications.
Increased lube orifice size to the 4th gear planetary gears.
Increased lube orifice size to the sun shaft.
The direct clutch is dual fed, meaning the direct clutch apply piston has more surface area for the fluid to act on. The drum is also drilled for faster fluid exhaust and clutch release.
I prefer green Borg HE frictions for fast, firm clutch apply. Forward and intermediate clutch packs have a HD wave/cushion plate for less shock loading of the sprags and rollers. End clearance on all clutch packs was adjusted to nominal specs.
A heavy duty spring pack, retainer plate and case snap ring is added to the intermediate clutch pack and clutch apply piston.
The 2-3, 3-4 accumulator is deleted. This decreases apply times and increases pressure for those gear changes. It also reduces the chance of any "cross-feeding" in the fluid circuits in that area of the valve body. The valve body itself is disassembled, cleaned and vacuum checked. The valve body separator plate is drilled to enlarge the orifices on all forward gear changes.
It has mild shifts at part throttle, and line pressures can still be tuned via HP tuners/Holley etc.
This recipe also features a rollerized output shaft. I replace the selective washer and thrust bushing with a roller-type needle bearing. This reduces drag. I also rollerize the forward clutch hub to direct drum now as well.
Core exchange fee is $600 for '99+ cases, Call for 91-98 case prices. I have cores on hand and am happy to build your unit with my stock, but charge a market-rate core exchange fee.
Please call 503 560 1852 to discuss custom builds, transbrake options (manual and automatic) and SFI bell/aftermarket cases
*for the immediate future I will not be processing deposits and build payments through squarespace. Contact me at douglassproston@gmail.com and I will email you a paypal invoice. Venmo, Cash or Check are accepted if you wish to avoid the 3.5% electronic payment processing fee.
the reason is squarespace is charging an additional fee on top of the paypal fee with the results totaling almost $100 in fees per $1000, which is unsustainable.
This is my base 750 hp “recipe.” This is the platform from which all transmission builds take form. I use this recipe in almost all of my 80e rebuilds. I personally have taken it to 750 wheel hp and use this exact build (with addition of a transbrake) in my (former, now sold) street/strip turbo LS G body that run 9.9x ET traps 140+ mph at Portland International Raceway. Every unit I build gets a 1 year warranty from date of purchase on component quality and workmanship.
The pump pressure regulator valve and spring are modified for more line pressure and correspondingly, modifications are needed to prevent issues from this. The pump body is drilled for a "line to lube" orifice to prevent excess charge pressure in the torque converter. The front seal exhaust port is enlarged to prevent blowing oil past the front seal.
With this increase in fluid flow and line pressure we can address some of the issues the 80e sees in high power, high load applications.
Increased lube orifice size to the 4th gear planetary gears.
Increased lube orifice size to the sun shaft.
The direct clutch is dual fed, meaning the direct clutch apply piston has more surface area for the fluid to act on. The drum is also drilled for faster fluid exhaust and clutch release.
I prefer green Borg HE frictions for fast, firm clutch apply. Forward and intermediate clutch packs have a HD wave/cushion plate for less shock loading of the sprags and rollers. End clearance on all clutch packs was adjusted to nominal specs.
A heavy duty spring pack, retainer plate and case snap ring is added to the intermediate clutch pack and clutch apply piston.
The 2-3, 3-4 accumulator is deleted. This decreases apply times and increases pressure for those gear changes. It also reduces the chance of any "cross-feeding" in the fluid circuits in that area of the valve body. The valve body itself is disassembled, cleaned and vacuum checked. The valve body separator plate is drilled to enlarge the orifices on all forward gear changes.
It has mild shifts at part throttle, and line pressures can still be tuned via HP tuners/Holley etc.
This recipe also features a rollerized output shaft. I replace the selective washer and thrust bushing with a roller-type needle bearing. This reduces drag. I also rollerize the forward clutch hub to direct drum now as well.
Core exchange fee is $600 for '99+ cases, Call for 91-98 case prices. I have cores on hand and am happy to build your unit with my stock, but charge a market-rate core exchange fee.
Please call 503 560 1852 to discuss custom builds, transbrake options (manual and automatic) and SFI bell/aftermarket cases
*for the immediate future I will not be processing deposits and build payments through squarespace. Contact me at douglassproston@gmail.com and I will email you a paypal invoice. Venmo, Cash or Check are accepted if you wish to avoid the 3.5% electronic payment processing fee.
the reason is squarespace is charging an additional fee on top of the paypal fee with the results totaling almost $100 in fees per $1000, which is unsustainable.