[Squidward]

Divorcing this question from my other thread for clarity.

Car came with st300 and shifter. Car now has th350, and will be going back to stock shifter that will be converted to a 3 speed with new detent plate.

The parts manual diagram shows 2 different trans levers depending on either AT or HD, with 2 different pn's.

Does anyone know the difference between the st300 and th400 trans shift levers? Is there maybe a different length? Different angle when mounted on the shaft?

Thanks!

[Squidward]

Ok, a little more research off the web. Apparently, the th350/400/st300 all have the same shift shaft intervals. Due to case external dimensions, the th400 uses a slightly different lever offset, but I suspect has the same hole to hole length.

My ST300 shift lever measures 3.25" center to center (hole to hole). There is 1/2" offset.

From the parts manual diagram, there are 3 part number differences in the linkages between th400 and st300: Trans lever arm, linkage rod, and shifter lever arm. I am hoping the only thing I will need to mod is the detent plate, and the rest of the geometry lines up.

[tanksteve]

The turbo 400 67 Firebird shifters that I have are about 3.75" center to center on the levers with a 1.5" offset. They also have a tab on the top to allow the neutral safety switch to mount high and they cut the bottom of the shifter body level with the bottom of pivot shaft. They almost certainly had to make those modifications when they found the original Camaro powerglide shifter would not clear a t-400.

An ST300 shifter might clear a T-350.

They used what i think is a modified ST-300 shifter for T-350 and T-400 in 68-72? Nova, and that shifter will work. Most 67 "Camaro" auto shifters advertised on Ebay and others are actually the later Nova shifters.

[Squidward]

Thanks, my friend.

I uninstalled all my previous shifter stuff, and installed my st300 shifter last night to get my final holes drilled. Before that, I measured, and the shifter lever arm was 3.5" with a 1" offset.

That slight length difference from sender to receiver tells me it is not a 1:1 motion ratio, so I might need to do some tuning to get the right shifter position to align with the gear select.

I also hooked up the rod between shifter and trans, and it feels like it is binding up somewhere near the governor cover. More crawling needed.

New True Slap detent plate arrives today.