DOUG S HEADERS DES102 LS Engine Swap Exhaust System Instruction Manual

: June 12, 2024
: DOUG S HEADERS

Table of Contents

DOUG S HEADERS DES102 LS Engine Swap Exhaust System
Product Information
Product Usage Instructions
INSTALLATION
DOUG’S HEADERS LIMITED WARRANTY
Parts List
Read User Manual Online (PDF format)
Download This Manual (PDF format)

DOUG S HEADERS DES102 LS Engine Swap Exhaust System

Product Information

The DES102 exhaust system is specifically designed as a bolt-on system for use in LS Swapped 1963-1972 Chevy/GMC C-10 Short Bed, Coil Spring, Truck Arm rear suspension trucks. It is compatible with Doug’s Headers and requires the use of Doug’s motor mount brackets and Doug’s transmission cross member.
Before starting the installation, please ensure that all the parts are included in the kit. If you have any doubts or questions, you can contact Doug’s Tech department at 909 599-5955.

Product Usage Instructions

Ensure that the LS engine and transmission swap is completely installed before proceeding with the installation of the exhaust system. Remove any existing exhaust and mounting brackets if they are still present.
Install the forward tailpipe hanger bracket to the U-Shaped shock absorber mount cross member using the existing holes in the cross member. The bracket should be positioned on the forward inner side of the U-Channel with the hanger rods towards the front of the truck. Slip one rubber isolator over each end of the hanger rods.
Install the rear tailpipe hangers to the outside of the frame rails above the rear tires. Each frame rail has one 5/8 and one 5/16 hole, and the brackets should be bolted to these holes using the provided hardware. Ensure that the smaller bent flanges on the brackets with two 1/4 holes are pointing downward.
Attach one tailpipe hanger bracket to each of the frame brackets using the supplied 1/4 hardware. The 1/2 hole on the bracket should be pointing downward. Bolt one rubber isolator to each bracket between the bracket and the frame. Install the 1/2 bolt in the rubber and secure the nut on the bracket side.
To ensure maximum ground clearance, you need to hole saw two large holes in the Truck Arm cross member for the exhaust to pass through the frame. Measure 5 1/2 inches from the inside of the frame rail towards the center of the truck and scribe a vertical mark. Scribe a horizontal mark at the center of the height of the cross member where your vertical mark is. This will be your center point for drilling. Use a 3 3/4 inch hole saw to drill a hole through the cross member. Repeat this step for the opposite side.
Slide the 2 1/4 inch Accu Seal clamp over one side of the H section of the H-Pipe and slip the H-Pipe together. Slip one 3 inch Accu Seal over each inlet end of the H-Pipe with the nuts facing down and the bolt/nut towards the inside of the H. Assemble the hanger assemblies as shown in the picture.
Slide a 3 inch Accu Seal clamp over the expanded end of each of the muffler intermediate pipes and slip the pipe over the outlet of the H-Pipe. Note that the driver and passenger side pipes are different. Snugly tighten the clamps, but do not fully tighten to allow for adjustment.
Slide a 3 inch Accu Seal clamp over one end of each muffler and install the muffler on the muffler intermediate pipe. Measure the distance from the inside of the frame rail to the front edge of the muffler and adjust the intermediate pipe until the muffler is 3 3/8 inches from the frame rail. Snugly tighten the clamp when everything is in place. Repeat this step for the other side.

PerTronix thanks you for choosing DOUG’S HEADERS, the best fitting, highest quality
Header and Engine Swap products on the market. TO realize the full potential Of our good fit, please read and understand these instructions completely prior to starting work.
Check to make sure you received the proper parts for your application against the parts list in these instructions. If you are unsure you have received the proper parts, please call PerTronix before you start work.
Be sure to work safe! Whenever you work underthe vehicle be sure that it is located on level, solid ground and is supported by adequate safety stands!
Remember : Hot asphalt will not support most jack stands!

NOTE : Read Before Starting Installation

This exhaust system is designed as a bolt on system specifically for use in LS Swapped 1963-1972 Chevy/GMC C-10 Short Bed, Coil Spring, Truck Arm rear suspension trucks.
This system will connect to the Doug’s Headers using Doug’s motor mount brackets and Doug’s transmission crossmember, Any other brand of mounts or headers will not necessarily fit.

INSTALLATION

Check that all the parts are in the kit before starting. If you are unsure, contact Doug’s Tech department at 909 599-5955.
The LS engine and transmission swap need to be completely installed before installing this exhaust system. If you haven’t already done so, remove all existing exhaust and mounting brackets.
Install the forward tailpipe hanger bracket to the U-Shaped shock absorber mount crossmember using existing holes in the crossmember. The bracket will go on the forward inner side of the
U- Channel with the hanger rods towards the Front of the truck. Slip one rubber isolator over each end of the hanger rods.
Install the rear tail pipe hangers to the outside of the frame rails above the rear tires. There is one 5/8” and one 5/16” hole in each frame rail, the brackets will bolt to these holes using the supplied hardware. the smaller bent flanges on the brackets with two 1/4” holes will point downward.
Attach one tailpipe hanger bracket to each of the frame brackets using the supplied 1/4” hardware with the 1/2” hole pointing downward. Bolt one rubber isolator to each bracket between the bracket and the frame. Install the 1/2” bolt in the rubber and put the nut on the bracket side.
For the Exhaust to pass through the frame and offer maximum ground clearance, you will need to Hole Saw two large holes in the Truck Arm crossmember. Measure 5 1/2” from the inside of the frame rail towards the center of the truck and scribe a vertical mark. Scribe a horizontal mark at the center of the height of the crossmember where your vertical mark is. This will be you center point for drilling, Using a 3 3/4” hole saw drill a hole through the crossmember. Repeat for the opposite side.
Slip the 2 1/4” Accu Seal clamp over one side the “H”” section of the H-Pipe and slip the H-Pipe together. Slip one 3” Accu Seal over each inlet end of the H-Pipe with the nuts facing down and the bolt/nut towards the inside of the H. Assemble the hanger assemblies as shown in the picture.
Slip the H-Pipe through the 3 3/4” holes in the crossmember and clamp it to the Headers using the V-Band Clamps, but do not fully tighten. Adjust the H-Pipe section until they are fairly centered in the crossmember holes and then tighten the H clamp and the V bands. Slide the hanger assemblies up against the cross member and mark the two mounting holes in each side. Remove the H-Pipe and drill 3/8” holes for the hanger brackets. Reinstall the H-pipe to the headers and attach the brackets to the crossmember, only snug the hardware.
Slide a 3” Accu Seal clamp over the expanded end of each of the muffler intermediate pipes and slip the pipe over the outlet of the H-Pipe. Note driver and passenger side are different. Snug the clamps but do no fully tighten to allow movement for adjustment.
Slide a 3” Accu Seal clamp over one end of each muffler and install the muffler on the muffler intermediate pipe. Measure the distance from the inside of the frame rail to the front edge of the muffler; adjust the intermediate pipe until the muffler is 3 3/8” from the frame rail. Snug the clamp when everything is in place. Repeat for the other side.
Slide a 3” Accu Seal Clamp onto the outlet of each muffler and then slide the over axle tubes in place from Behind the axle, slipping them into the mufflers. Insert the hanger rod into the rubber isolator installed in step 5.
Slide a 3” Accu Seal clamp over over the tail pipe inlets and slip the tailpipes onto the over axle pipes, inserting the hangar rods through the rubber isolators that you installed in step 3.
Adjust all of the pipes and brackets for the best location and centering in the crossmember. Watch for clearances of all pipes between the frame, gas tank, etc. When you are satisfied with the best fit, starting at the front and working rearward, tighten all the brackets, followed by the Accu Seal Clamps (60 lbs. ft.), making sure the pipes don’t move as you tighten them. You may have to loosen clamps as you work your way back in order to align other components, take your time and exercise extreme patience.
Congratulations, you are done. Check all clamps and fasteners after about 50 miles and again once a year.

This product is designed for swapping a non-original engine into a vehicle that did not offer it. Laws vary by state regarding emissions regulations for engine swaps. This product is Illegal for Street or Off Highway use on any 1975 or newer vehicle originally equipped with a catalytic converter and may further be illegal depending on state or federal engine swap emissions laws regardless of vehicle year and would therefore only be legal for Closed Course Competition use. 1’ar7ro11ix 1’a,10,,,.t111ea 8rt111ds 2021

DOUG’S HEADERS LIMITED WARRANTY

All Doug’s Headers and Exhaust products are guaranteed, to the original purchaser, to be free of defects in material and workmanship for one year from date of purchase. This warranty covers the replacement or repair of the product and does not cover the cost of removal and installation, customer applied coatings, or Any discoloration or corrosion of finished surfaces.
Damage or product failure resulting from collision, improper installation, off road use, road hazards, the use of exhaust insulating wrap, or rust occurring after installation is not covered by the warranty. This warranty extends only to the original purchaser.
Should a part be deemed defective, it should be returned to the original selling retailer and must be accompanied by the sales receipt. If there is no retailer in your area, contact PerTronix direct for a return authorization and return the part prepaid to the factory for inspection. PerTronix reserves the right to replace or repair the alleged defective part and return the part freight collect.