M6 to TH350 or TH400 swap - read stickies.
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I bought a 408ci stroker car with a 6spd. It made 475rwhp the way it sits, should be over 500rwhp pretty soon plus I'm planning on a 100-200 shot on top of it.
I'm wanting to convert to an auto to be a little more street friendly but mostly for track season next year. It's a street/strip car, not a daily driver. Just planning on taking it out on nice days/nights and having some fun, and racing regularly when the season opens.
So, do I go with a TH350 or TH400? Either way, it's going to have a RMVB and a brake.
I'd like a 400 because of the extra strength, but a TH350 is more efficient, and with a 9" tail shaft it will retain my driveshaft.. which is a huge plus because it's an expensive aftermarket unit. I have a tunnel mounted TQ arm so that isn't a factor in deciding. In the sticky it said a TH400 with a 4" TS will use the stock M6 crossmember, but it doesn't say anything about a crossmember for a TH350. If I have to make a crossmember that is fine.
And where can I find a tailhousing with the electronic speedometer setup? I'm not interested in hacking the ABS wire and having an inaccurate speedo and no ABS, it's going to be street driven much more than the track so having ABS and knowing the proper speed is a must. I had a sponsor quote me $275 to add the plug-and-play setup to a trans they quoted me, but i didn't know if they were available elsewhere if I decide to build the trans myself.
For an extreme duty th350 with plug and play speedo I was quoted around $2100 + a core from a great sponsor.. but I'm hoping I can build one myself and save some money.
I'm wanting to convert to an auto to be a little more street friendly but mostly for track season next year. It's a street/strip car, not a daily driver. Just planning on taking it out on nice days/nights and having some fun, and racing regularly when the season opens.
So, do I go with a TH350 or TH400? Either way, it's going to have a RMVB and a brake.
I'd like a 400 because of the extra strength, but a TH350 is more efficient, and with a 9" tail shaft it will retain my driveshaft.. which is a huge plus because it's an expensive aftermarket unit. I have a tunnel mounted TQ arm so that isn't a factor in deciding. In the sticky it said a TH400 with a 4" TS will use the stock M6 crossmember, but it doesn't say anything about a crossmember for a TH350. If I have to make a crossmember that is fine.
And where can I find a tailhousing with the electronic speedometer setup? I'm not interested in hacking the ABS wire and having an inaccurate speedo and no ABS, it's going to be street driven much more than the track so having ABS and knowing the proper speed is a must. I had a sponsor quote me $275 to add the plug-and-play setup to a trans they quoted me, but i didn't know if they were available elsewhere if I decide to build the trans myself.
For an extreme duty th350 with plug and play speedo I was quoted around $2100 + a core from a great sponsor.. but I'm hoping I can build one myself and save some money.