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Old 05-01-2024, 09:23 PM
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Default 2 Questions about my ride

Car is a '65 Lamnas. I'm going to run a TH400 trans. There are no bolt holes for proper positioning of the trans x-member and if I simply scoot it rearward the ~6 inches or whatever, it won't be the right height. I can probably shim it, but was wondering if someone makes an aftermarket x-member that will work? I've looked around a bit, but have not seen anything available in the

2nd question is about the gas pedal. I don't like the floor mounted style of the 64-65 cars, with the 2 studs protruding from the floor pan. Can I convert to the 66-later style pedal linkage and pedal without too much trouble?

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Old 05-01-2024, 10:52 PM
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For the crossmember call speedway motors and ask about a G force crossmember for you car! I don’t know much about the lemans peddles

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Old 05-01-2024, 11:54 PM
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There is 3 inches difference between a T 350, and a T 400 trans mount, or a 2 speed, ST300.

I've swapped T 400s into 65, 67, and 68 hardtops without any problems just using the standard crossmember, and drilling an extra hole on either side. I wouldn't spend the money for an aftermarket crossmember, but it's not my car, or my wallet.

Now if you have the fully boxed HD frame, or a convertible, you would need to do some fabrication to slide the tab welded to the inner channel rearward. GM first used the T 400 in 67, so they should have coresponding holes already.

I can't answer definitively about the gas pedal, but I doubt GM redesigned the sheetmetal of the firewall from 65, to 66. My best guess would be a minor change to adapt the later pedal, if there was any change at all.

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Old 05-02-2024, 12:50 AM
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I did it on a '66 Tempest, but it's been a minute...the height difference still bothers me so I can probably just make a shim. If I'm remembering right, just the mid '66-earlier frames have no height provision for the position of the holes when they're correctly positioned for a TH400 whether it's 3 or 6 inches....dimension is not so much mattering in this case.

I'm wanting to get everything lined up well to minimize parasitics and any further unnecessary power loss....TH400s take around 40-ish hp..? Not sure on that. This one's gonna be my last build I think....we'll see.
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Old 05-02-2024, 02:09 AM
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When I converted my ‘64 to TH400 all I did was move the crossmember back and drill 4 new holes for the 2 hold down brackets. Those 2 brackets retain the rubber insulators that cap the ends of the crossmember. The frame doesn't have a perfectly flat area where the rubber insulators nest, but it works fine.

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Old 05-02-2024, 07:35 AM
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Quote:
Originally Posted by b-man View Post
When I converted my ‘64 to TH400 all I did was move the crossmember back and drill 4 new holes for the 2 hold down brackets. Those 2 brackets retain the rubber insulators that cap the ends of the crossmember. The frame doesn't have a perfectly flat area where the rubber insulators nest, but it works fine.
My experience also with a '65.

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Old 05-02-2024, 10:27 AM
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I used a 66 gas pedal assy in my 64 lemans a few years ago. Don't remember all the particulars, but seems that it bolted-in easily enough but the angle seemed high. Maybe I heated the metal rod of the pedal and bent it down a little, don't really remember, but it worked out fine

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Old 05-02-2024, 12:48 PM
KEN CROCIE KEN CROCIE is offline
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slide it and drill it.

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Old 05-02-2024, 03:37 PM
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Not to sound like a broken record but I converted both my 65 and 67 LeMans to a TH-400 and all I did is move it and drill it just like Ken said. I never noticed a height difference, not say it's not just never noticed one.

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Old 05-02-2024, 03:46 PM
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The crossmember will be tilted rearward at a very slight angle when you slide it back if you retain the stock rubber insulators and clamp mounting. This presents zero issues.

You can also simply drill 2 holes on each end of the crossmember and omit the rubber insulators and clamps. This allows the crossmember ends to sit flat.

I’ve done it both ways. The Chevelle crossmember bolts directly to the frame unlike Pontiac but you can bolt the Pontiac crossmember directly and it works great.

Either way you’re sliding the crossmember back pretty much a full 6” and drilling 4 new holes in the frame.

Easy peasy.

Pictured below is the crossmember on my old GTO bracket car bolted directly to the frame. The GTO was equipped with a ‘71 455 HO, reverse manual valve body transbraked TH400, a 3.89 geared Ford 9” rear along with 10x28” Goodyear slicks.
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Old 05-02-2024, 06:54 PM
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Quote:
Originally Posted by b-man View Post
The crossmember will be tilted rearward at a very slight angle when you slide it back if you retain the stock rubber insulators and clamp mounting. This presents zero issues.

You can also simply drill 2 holes on each end of the crossmember and omit the rubber insulators and clamps. This allows the crossmember ends to sit flat.

I’ve done it both ways. The Chevelle crossmember bolts directly to the frame unlike Pontiac but you can bolt the Pontiac crossmember directly and it works great.

Either way you’re sliding the crossmember back pretty much a full 6” and drilling 4 new holes in the frame.

Easy peasy.

Pictured below is the crossmember on my old GTO bracket car bolted directly to the frame. The GTO was equipped with a ‘71 455 HO, reverse manual valve body transbraked TH400, a 3.89 geared Ford 9” rear along with 10x28” Goodyear slicks.
Not to derail too much here…
Bolting xmember directly to the frame, would that alleviate somewhat the driveline angle issues I’ve read about using poly trans mounts? They’re higher than factory rubber, and I recall people saying that was a problem.

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Old 05-02-2024, 07:05 PM
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Quote:
Originally Posted by rolling money pits View Post
Not to derail too much here…
Bolting xmember directly to the frame, would that alleviate somewhat the driveline angle issues I’ve read about using poly trans mounts? They’re higher than factory rubber, and I recall people saying that was a problem.
Might help.

Measure from the crossmember to the floor pan with and without the rubber insulators, just rest the bare crossmember ends on the top of the frame to see.

Or eliminate the issue and just use a rubber trans mount, I used all stock rubber mounts on my bracket car with no problems. I did use a chain on the driver side to limit engine movement but that’s all.

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Old 05-02-2024, 07:18 PM
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I actually rotated the crossmember 180 degrees and only had to drill one hole on each side.

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  #14  
Old 05-03-2024, 01:00 AM
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65 Lamnas,
For using a suspended gas pedal you might want to look at this link. It's actually for installing a suspended pedal in a Cheby C10 pickup but has some great pics & info. I also own a 64 Cheby C10 besides my 62 Catalina. Mine was more a hodge podge of parts. The pedal came from a 73 Nove, but the bracket I used was from a 73 Full Size Pontiac - I did have to heat & bend the rod ti make it all fit & look correct & my throttle cable came from a 73 Chevy C10. Don't be afraid to hunt around to mix & match to get teh look & function you want. If you're at all curious my POS C10 is shown in post #21 with the suspended gas pedal installed.

Link: https://67-72chevytrucks.com/vboard/....php?t=530828\

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