Just started to do my swap into my 51 GMC with 81 Malibu front end & my manifolds apear to be too wide for the chassis. Anyone know of any headers that tuck closer to the motor? This could be a show stoper!!
Details of current motor assy. are 2004 GMC seria P/U (5.3)

 

I used 2000 or 2001 F-body exhaust manifolds in my el camino, I am pretty sure that 98 - 02 f-body manifolds will fit, but I think no matter what year you use you will have to move the oxgen sensors, but that is no big deal. I only had to move the drivers side o2 sensor.

 

Im having the same problem with my `1992 ford ranger swap. Hedman and hooker both make block hugger headers that look like they will work for you. Maybe a different stock manifold will clear better. I have a set of '02 Camaro manifolds if you are interested.

 

You may could use some GTO stock manifolds like these. I had a pair but sold them. They are closer to the engine and have a smaller outlet.

 

Thanks G-body, I will try to come up with some F-body manifolds. Any suggestions for motor mounts?

 

I just got them. They are perfect for my application. Thanks 55chevy!

 

I am using Sanderson headers on mine. They have several LSx models. They are smaller 1.5" tubes, but for my application that will be fine as long as they fit. I am having to modify the driverside for steering box clearance. I have a narrowed Nova subframe and that is presenting some challenges. I am posting pics of the passenger and driver's side before modification. you can see more details by following the link to my project journal in my signature. The Sanderson price was reasonable, I paid $250 for plain steel and they will ceramic coat them for me once the mods are done for $110. Sanderson has been great to work with providing me extra pieces of pipe and bends to do my modifications for a small charge.

Pat

 

I used mounts that I bought from 5.3 Racer when he took his car apart. There are pics in this thread on the second page. https://ls1tech.com/forums/conversions-swaps/252644-ls1-swap-into-1986-elcamino.html
If you think they might be of use to you I can email/post the dimensions for them.

 

Pat, do you know what the distance between the two collectors is when the headers are bolted to the engine ?

 

These are the 1997 first design Corvette manifolds.....tuck in ok for a factory manifold

 

i have some z06 manifolds.
they are closer to the motor, and exit more in the center.
if they would work for you, i do have a set id sell inexpensive.

 

I don't have that figure yet, possibly will have it this afternoon. Also relative to that measurement is how high or low the collecter is. In pictures the CTS-V manifolds looked like they woulld work perfect for me, but they turned out to have the collector too high and hit my steering box. If the collectors would have been lower, like the Fbody manifolds, they would have worked.

I will post pictures as soon as we have a good fit.

Pat