Want input from Subframe experts

[48builder]

I'm getting ready to order my radiator. I'm having an aluminum unit made so I can get what I want. The LT1 has some peculiarities when it comes to cooling. I have an '87 Gran Prix front clip in my '48 Chevy sedan. Since it is a front steer, the stock radiator support has to be modified to fit around the steering box.

I had a spare support, so I started cutting it up to make it fit, and I started thinking about alternatives. I figure I have a couple options.

I can make a support similar to the stock one out of 1-1/2 angle, and shape it to go around the steering box. I also have to make a support coming up from the crossmember to hold up the bottom of the radiator support. Then I can just have the radiator guy make a couple flat tabs off the side of the rad and bolt it to the angle.

Or, I was thinking I could make some supports out of the same 1-1/2 angle and attach them to the frame rails. I'd have the fenders bolt to these supports just like the original. Then I could bolt some angle on the inside of them, and attach the radiator in the same way. I wouldn't have to worry about a support from the crossmember, and it seems like it might be easier overall. I would have to make some bracing across the front like the original radiator support has, but that's easy.

I figure enjenjo has done a few subs, and I know Sumner and Bob K have. Anybody have some pros and cons I should consider?

[enjenjo]

Here's some pictures of one I am working on right now. It's a truck, but the same sub frame. What I did was tip the bottom of the radiator forward to clear the steering box. The core support was modified to go inside the box too.

[1FATGMC]

   

I used the Radiator and core support from the 73 Camaro I got the clip from. I used a couple pieces of square tubing to brace it. You can see a little of this in the picture above. I trimmed the sides of the core support so that the inner fenders would clear it when you tilt the front.  I also had to section out a piece from the side core supports to get the radiator where I wanted it vertically.

   

Not real pretty, but it uses all of the stock rubber mounting top and bottom to hold the radiator in place.  Another nice thing is I'm able to run the stock fan shroud and fan.  I like having as much as possible stock pieces for ease of replacement parts while on the road.

I'm running a new 4 core a friend of Hooley's built for me in Ok. this past summer when my old one developed some bad holes last spring.  I keep the original 2 core I had as a replacement if something goes wrong with the 4 core like what happened to the old one last spring.  It is about a 15 minute job to swap it in when needed.

There are some more pictures (  HERE ).

c ya, Sum

[WZ JUNK]

The LT1 has some peculiarities when it comes to cooling.

I did an LT 1 engine in a 56 Plymouth last year.  I used the radiator/condensor/with cooling fans from a 96 Trans AM.  I used the factory rubber saddles top and bottom and fabricated the new mounts for them.  I like to use the factory mounting cushions whenever possible and that is just about all the time.  They let the radiator float but still hold it in place.  I feel a rigid mounted radiator is more apt to be subjected to vibration and twisting stress and can cause the radiator to leak.  The LT 1 being a reverse water flow engine calls for some planning when doing the radiator hook up.  I have seen some that were done wrong but being driven.

[1FATGMC]

The LT1 has some peculiarities when it comes to cooling.

I like to use the factory mounting cushions whenever possible and that is just about all the time.  They let the radiator float but still hold it in place.  I feel a rigid mounted radiator is more apt to be subjected to vibration and twisting stress and can cause the radiator to leak.

I agree.  

Good talking to you today John,

Sum

[Bob K]

I agree totally about the mounting solid. I mounted the first Walker radiator right to the angle. I shook it apart in the first 45k.

I used Harley Davidson oil tank mounting hardware when I replaced the radiator and used the same system on the 52 vert. No more shakey shakey and have put another 60k on the 47 and 25k on the 52 with no trouble.







I also put 2 on the bottom on a bracket I made to give it some vertical support.

B B

[48builder]

Thanks for the info, guys. I went out and looked, and I can't angle my stock mount like enjenjo. It would be at about 45 degrees. I think I will use a combination of making my own radiator frame and mounting it to the frame rails. I'll either use some stock saddle mounts or the Harley mounts like Bob. I have a friend with a big shear press and a brake. I'll have him make some channel the right width for my radiator and go from there.

Walt