The reason they don't spec 4t65e's for more power anymore is because the parts we used to build them up with are no longer on the market. I have at least 3 major components in my transmission that are not replaceable, and I didn't even get them all.
Another big reason is because the demand no longer supports the market to supply parts that cost companies a ton to develop/maintain. Out of the hundreds/thousands of folks that muse about building up a "big power 3800" each year online, maybe 5-10 actually go thru the process of not only buying all the necessary parts, but also getting it running and dialed in to perform at a level that would need $3k+ invested in the transmission.
A 4t80e conversion is an option that a few have done, but you'll need to talk with those who were successful (turbocharged400sbc - James - can talk your ear off about it). You can see some details in LS4king's youtube videos on the swap in those cars, but he's mostly backed out of the market for personal reasons.
For FWD transmissions, there's limited options. Honda boiz spend thousands on billet cases to try holding big power, and aside from the GM Racing 4t65e we got a few parts from in ~2006, nobody cared to push upgrades for an automatic FWD... The solution to going fast reliably is always cubic dollars in the car world.
Another big reason is because the demand no longer supports the market to supply parts that cost companies a ton to develop/maintain. Out of the hundreds/thousands of folks that muse about building up a "big power 3800" each year online, maybe 5-10 actually go thru the process of not only buying all the necessary parts, but also getting it running and dialed in to perform at a level that would need $3k+ invested in the transmission.
A 4t80e conversion is an option that a few have done, but you'll need to talk with those who were successful (turbocharged400sbc - James - can talk your ear off about it). You can see some details in LS4king's youtube videos on the swap in those cars, but he's mostly backed out of the market for personal reasons.
For FWD transmissions, there's limited options. Honda boiz spend thousands on billet cases to try holding big power, and aside from the GM Racing 4t65e we got a few parts from in ~2006, nobody cared to push upgrades for an automatic FWD... The solution to going fast reliably is always cubic dollars in the car world.
