Downpipe reroute

[liquidswords88]

I recently completed work on my homemade 3" "Jsm" style downpipe. I bought a bunch of random 3" mandrel bends and butt welded them. While I was figuring out my plan of attack, I thought that since I am not running inner fender wells I should use the space. I made my downpipe in a fashion that it turns away from the engine and then swings back in and down. This design prevents the down pipe from being so close to the plug wires. It also keeps the downpipe from transferring radiant heat into the engine. As a bonus it gives much more room for the starter wiring which in my opinion is perilously close with a stock downpipe.

 

[TYTILIDIE]

Re: Downpipe reroute

Biggest problem with no inner fenders is that if you spent a lot of time and money making a nice engine bay it will be for nothing as it will get pretty nasty in there. The down pipe running close to the plug wire is fairly irrelevant unless it's within 1/2" or so and even then it shouldn't be that big a deal. Same with the starter minus the wiring. A lot of people run a remote solenoid which imo makes a huge difference and takes a lot of reliability and starting issues out of the equation.

Unless your truck is a weekend cruiser in no weather you will likely regret no inner fenders. I remember being so excited to see all the room and having that race car look and after one rain that I wasn't expecting it never looked the same no matter well I cleaned.

Heat soak is a huge pita on these trucks but it is mainly due to the a2w set up. You can minimize it but if you install a meth inj set up youll be tickled and forget the heat soak issue. Or you can run a2a which also makes a big difference. On a 90* day I can have an IAT of 140* sitting at a light and watch it drop to about 95* in a few seconds. With meth, you can watch your 140* IAT at the stage drop to 50* by the end of a 1/4 run.

 

[liquidswords88]

Re: Downpipe reroute

I wouldn't even consider my truck a weekend cruiser...lol. It's more like a full scale model that sits in storage instead of a shelf. If it sees 500 miles a year that would be max. I don't get projects going in an effort to use them, it's more for something to do.