Header Clearance. Need Advice!

[CJM72]

Hello Friends. Been picking away at my swap and the other night I mounted my Doug Thorley headers (Thy‑324y‑c) to my LQ9/4l65e combo in my 1972 Blazer. Everything bolted up nice and easy.

After a quick final inspection, I realized my drivers side header is basically touching the firewall where it kicks down. It bolted up easily, but I barely can fit a piece of paper in there!

So question is...how do I get some clearance in there short of beating on the firewall? I may try loosening up everthing on my Dirty Dingo mounts to see if I can 'clock' the motor a bit, but it seems like the soft motor mounts will just sink back to there normal level. Could collapsed body mounts be the problem?

Spacing seems pretty even on both front mounts and it appears the previous owner has 2 shims on both sides. Anybody have a measuremnent between the rocker box or floor and their mount with fresh body mounts? I ordered up a set of new mounts from Wes.

Headers are ceramic coated, but not sure I want them touch the fire wall like that!

[CJM72]

After examining the problem, I think I should rephrase the question here. What do you guys feel is a minimum amount of clearance between a driver's side header and the firewall? When the engine torques (twists) the driver's side header is going to rise into the firewall. New mounts might give me an 1/8" of clearance, but I'm guessing that I need 3/4" to be comfortable. The offending section of the firewall has some bends and ribbing built in that might not be great to beat in.

I'd love to use these headers and sell my LS3 manifolds, but If I can't figure out a fix soon I'll have to throw these up for sale and try to get my manifolds coated instead. Thanks

[CJM72]

Update. I found out I can actually read LMC on the body mounts. This means that the guy that had the Blazer before me must have replaced the mounts when he did the body work about 2 years ago now.

I know the LMC Mounts aren't the best, but I doubt they totally collapsed in 2 years time and almost no miles. Guess I have two options: 1. Put a big ass dent in the firewall in the drivers footwell. 2. Sell these headers and put my manifolds on. Don't think I like either option! Still open to suggestions.

[clemsonteg]

These headers are designed for our trucks, right? I would think they would fit better. Maybe the 4wd?

[CJM72]

These are headers ate specifically made for our trucks, but I've heard the Dirty Dingo crossmember does raise the motor up a bit. Pics in 2wd applications and other trucks appear to have a lot more room.

[dayj1]

Do you have the option of moving the engine forward in the chassis?

[CJM72]

In theory yes, but my whole choice of components was based around keeping the transfer case in the stock location so I could use the stock driveshafts. Too bad, the headers look fantastic.

[CJM72]

Hi Guys,

I've decided to just pull these off, take the hit, and sell them. I have LS3 manifolds and I don't want to fight these. Too bad...they seem to work for almost everyone else and they look awesome. Doug Thorley quality seems to be top notch.

Where do you guys have the best luck selling? I could become a paying member and sell them here, or throw them up on Ebay. Of course I threw the box away before I realized I had clearance issues!