How much frame in front of firewall?

[coostv]

I know this is subjective, but how much frame do I need in front of the firewall? I plan to use a 350/700r4 combo, suicide front, and possibly a small recess in the firewall.

I have searched with all the terms I could think of and came up blank...

I read somewhere that 31.5" was a good number to start with and subtract from that for the recessed firewall. Sound accurate?

Thanks,

Chris

 

[Gastrick]

It's subjective once you have enough room for all your components. If I'm building a chassis from scratch, I mock everything up first (body/engine/radiator) and then I make sure the total package fits and looks proportionate (that's the subjective part). I build the chassis accordingly from there. I'm not sure what you are building but it sounds like it won't have a hood or fenders which leaves you more options.

 

[HOT40ROD]

My model T rat pickup is setting on a Model a frame. The way I when about was. I sat the front axle fcirst , Then the radiator and grille and the motor and trans. After all of that I slid the cab up behind the motor until it looked right.

Then I cut the frame at the rear and add about 5 inches to the wheelbase to balance it out.

Not the best picture but here what I came up with.

 

[coostv]

I plan to build an entirely scratch built car. I have seen quite a few builds where the chassis is built first and the body is built second. I have an overall plan, I am trying to iron out a few details before the first weld is burned.

My thoughts were to build the chassis first, but after talking to guy from work he suggested I do the body first for the same reason Gastrick... I may do the firewall and frame of the body so I have a reference point for the chassis.

Seems easy until you are ready to pull the trigger and get materials for the project!

I am going to post this project and if finances allow I would like to complete it in a year'ish.

 

[RPM]

We build a lot of T Bucket frames or rat frames. We allow 42" from the front of the flat firewall to the front of the round tube, in the very front of the frame. We set the engine/trans seam 2" in front of the firewall. This will work with just about any v-8 engine and allow enough room for a blower drive if needed.

 

[King Herald]

Lay your parts out first, make sure things look right, clear each other etc. It'll depend on the body style too, if you're building a shorty trad T bucket, or a longer RPU sort of thing.

 

[donsrods]

After you get a figure, add an inch or two. Every time I do one I wish I had left just a tad more room for unexpected things, like electric fan clearance, distributor clearance, etc. I've never seen it fail that things get a little tight no matter how carefully you measure.

Don

 

[meyek91974]

an easy idea if it helps ya

ok, for example, I am building a t-bucket, but I am not using a V8 and want an extra inch here and there. - So it's not typical.

I bought the front cross section (26") and the two main lengths going back, but I got them an extra 18" too long. So, as I mock up the radiator, engine, tranny, drive shaft, set the rear, measure to plop a bucket of a "body", and so forth I can measure and make the final cut for the rise and rear "deck". I know it's not the common way, but just remember as I've been told "measure twice to cut once" - well, measure four or five times and then cut.....

AND EVEN BETTER, mock up with 2x4's to then have steel done right once. - just put jack stands under your 2x4's at the motor mounts and high load bearing points

 

[RPM]

You can get some big card board boxes. Like refrigerator or washing machines come in. Lay them out on the garage floor and draw what you need and draw it all to actual size. No saw dust that way, (I hate that stuff) real easy to make changes and it won't cost a penny to do it.

 

[IAM-LDS-2]

You say you are building a car , coupe , 2 door or 4 door ?

 

[HOT40ROD]

There one guy locally that build the frame out of 2X4s because it cheap and he get it the way he wants it before he cut the steel and builds the frame. He always says that it cheaper to miss up a piece of wood then the steel.

 

[Jimmy Wallbanger]

that wood work . GET IT!

I measure a few times on guessing where stuff would go then zd it to fit the cab making sure that I left alot xtra in the front. then measured the motor rad and such. you can always shorten the front if you have to luckily i didnt have to. just tack stuff and use temp cross members to be sure.