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Tim240Z · 04-01-2005, 01:24 AM

I used the headers that I had on my 350 that I took out of there. like I said above I wanted to keep the OEM manifolds to keep all the EGR stuff, but 'Oh Well'!
No problem with the auto 4 speed (4L60E), but there just wasn't enough tunnel 'hump' to push it back like I had hoped.....I'm hoping for 18-20 mpg.

The only thing I had to do to mount the tranny was drill a hole in the X-member for the tranny mount (TH350 has 2 bolts, the 4L60E only has one stud that connects it to the X-member.)

04-01-2005, 01:24 AM	#7
Tim240Z Senior Member Join Date: Jan 2005 Location: LAX area, So Cal Posts: 499	I used the headers that I had on my 350 that I took out of there. like I said above I wanted to keep the OEM manifolds to keep all the EGR stuff, but 'Oh Well'! No problem with the auto 4 speed (4L60E), but there just wasn't enough tunnel 'hump' to push it back like I had hoped.....I'm hoping for 18-20 mpg. The only thing I had to do to mount the tranny was drill a hole in the X-member for the tranny mount (TH350 has 2 bolts, the 4L60E only has one stud that connects it to the X-member.) __________________ 1972 Suburban C20 454/TH700R4, eaton-corporate 4.10 (looking for 3.7) Sold: 71 Cheyenne 20 Installed a 99 5.7L L31/4L60E from Suburban 1500 (2005)