LT1 conversion trans thoughts.
Thread Starter
Drifting
Joined: Aug 2007
Posts: 1,838
Likes: 13
From: Kingman AZ
LT1 conversion trans thoughts.
I've been gifted a 355 LT1. Gifted in the sense I am only paying 1800 dollars. A new rotation assembly cost that much. Hot cam , forged balanced. Etc. Expected 400/450 hp. If you did this swap what transmission would you suggest, 700r4, 4l65e,, 4L80e or a manual 5 or 6 speed. Manual route is gonna stretch the budget with pedals and all.
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Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
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all the bits to convert to manual can be purchased as a kit from Zip. however bits can be sourced used as well.
Me, I Vote manual. much more fun factor. as well as it will increase the value of your car.
which manual? kinda depends on your rear gear. and what you can get a good price on.
Me, I Vote manual. much more fun factor. as well as it will increase the value of your car.
which manual? kinda depends on your rear gear. and what you can get a good price on.
Advanced
Joined: May 2020
Posts: 76
Likes: 7
From: MA
all the bits to convert to manual can be purchased as a kit from Zip. however bits can be sourced used as well.
Me, I Vote manual. much more fun factor. as well as it will increase the value of your car.
which manual? kinda depends on your rear gear. and what you can get a good price on.
Me, I Vote manual. much more fun factor. as well as it will increase the value of your car.
which manual? kinda depends on your rear gear. and what you can get a good price on.
In my 69, I have an M22 with 308's. 85 - 90 MPH is around 3 to 4k RPM's Kind of wish my car had at least a 5th because my car loves to be at 80 and above. Its happy there.
Good luck with your conversion.
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,079
Likes: 4,431
From: Marlton NJ
My LT1 did not mind 3000 rpm at 70 in the slightest with 355 gears. and a WR M20. But these days I would slow it down a little to 2500ish cruise with a TKO 5 speed. No way I would put an auto behind it,!
Play with gears here til you get it right.
I would think a TKX CR with .81 OD with 355s would be just about perfect in a good revving LT1
Play with gears here til you get it right.
I would think a TKX CR with .81 OD with 355s would be just about perfect in a good revving LT1
Last edited by leigh1322; Jan 3, 2021 at 12:28 AM.
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,079
Likes: 4,431
From: Marlton NJ
Sorry but I must disagree. I have seen too many guys put 5 or 6 spds in their car, with too much of an overdrive in it, and then are not all that happy. You need to look at both ends, not just one.
The TKX CR will give him the best of both worlds. It'll run like a scalded dog as if it had 411s in it, then cruise nice at 60-70-80 mph
With 355s he'll have 10.2 in it in first, and a tight gear spread, and a 2500 rpm cruise at 70 You could probably use 5th from 60 up. What's not to like?
Yes you could put more gear in it in first. And yeah you could put more OD in it. But does it really need either?
The TKX CR will give him the best of both worlds. It'll run like a scalded dog as if it had 411s in it, then cruise nice at 60-70-80 mph
With 355s he'll have 10.2 in it in first, and a tight gear spread, and a 2500 rpm cruise at 70 You could probably use 5th from 60 up. What's not to like?
Yes you could put more gear in it in first. And yeah you could put more OD in it. But does it really need either?
Last edited by leigh1322; Jan 3, 2021 at 02:31 PM.
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