Time for new exhaust need help

[ORANGECRUSHer]

My 1835 baja needs a new exhaust. I’m about to change the dual Kadrons to dual 40 HPMXs too! For all I know the rest of the engine is stock. I had a 1-5/8” bugpack quiet pack bobcat type ceramic exhaust.

I’m wondering if i need 1-5/8”? Prices are about the same either way. I’m thinking about going with a 1-1/2 this time. Maybe a sidewinder style. I think ill try the Tri-mill brand as well.

What do you guys think? What works for my combo? I can’t make up my mind. Maybe just a raw stinger type for now to try out a 1-1/2?
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Brian H.
I may not know everything,but I will try to help if I can
OrangeCrushER Berrien Warrior 2.4L Quad4
LAZY MARY 1970 Baja 1835cc

[Vanillagurilla]

I have 1 5/8 u bend on mine with a 12in glass pack type muffler, 1 5/8 is actually to big for an 1835 but my car doesn't seem to care. You might get a little more torque from a 1 3/8 exhaust.

[L5wolvesf]

There are calculations available that are designed for optimum performance based on a book by A. Graham Bell called Performance Tuning in Theory and Practice, Four Strokes.

http://www.wallaceracing.com/header_length.php
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Amonster Motorsports

SNORE # 1196 sponsored by:
- www.356carburetorrescue.com/home.html
- Barnwerks Fabrication & Welding
- ArtSpeed Graphics

“Racing's important to men who do it well. When you're racing, it's life. Anything that happens before or after is just waiting.”
S. McQueen

[plotch]

What happened to the ceramic coated?

[ORANGECRUSHer]

It's getting pretty rough. rusty, flakey coating and the muffler has rubbed a hole in itself. Oh and there was a spot I had to weld a patch onto because it was starting to rust through.
It's actually surprising these exhausts last as long as they do. I think I'll try the 1-1/2". I've got enough going on with having to jet these HPMX's let alone reading up on engine calculations. Ordinarily I'd be interested but I just want it up and running at this point. I don't have a lot of time to study before I make a decision. Just thought I'd see what people thought since it's not an uncommon setup. Basically a 1600 DP with an 1835 jug kit and duals. whoopie!

Thanks to everyone who gave me input. Gonna order tomorrow morning. I'm planning on this being my DD again this summer. I need some fun in my life.
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Brian H.
I may not know everything,but I will try to help if I can
OrangeCrushER Berrien Warrior 2.4L Quad4
LAZY MARY 1970 Baja 1835cc

[dustymojave]

1.5" is PLENTY.

I've run my 1835 with 1.5" headers for decades. I won a championship with an 1835 with 1.5" TriMil Bobcat headers as you see in my avatar.
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Richard
Offroading VW based cars since 1965
Tech Inspection 1963 - 2012 SCCA/SCORE/HDRA/MORE/MDR +
Retired from building Bajas, Fiberglass Buggies and Rails in the Mojave Desert. Also Sprints & Midgets, Dry Lakes, Road Race cars. All types New and Vintage
SoCalBajas Member
Kicked Cancer's A$$...1st and 2nd round...Fight ain't over yet.

[ORANGECRUSHer]

Thanks Richard. The vendor near me sells the Empi equivalent of the Tri-Mill bobcat and I think I'll get that for now due to availability. Eventually I'd like to get a Tri-Mill though. probably from Moore Parts. It's been awhile since I heard a VW without a muffler of some sort. Wonder if I'll be ok in the city?
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Brian H.
I may not know everything,but I will try to help if I can
OrangeCrushER Berrien Warrior 2.4L Quad4
LAZY MARY 1970 Baja 1835cc

[dustymojave]

Downturn collector with a 2" Thrush Turbo muffler. Sounds great but quiet enough to not bother the neighbors or get cop attention. And only costs like $30 most anywhere. Makes more power than a quiet pack too. DON'T get a "Super Turbo". They have fiberglass packing that doesn't last long and they sound crappy.
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Richard
Offroading VW based cars since 1965
Tech Inspection 1963 - 2012 SCCA/SCORE/HDRA/MORE/MDR +
Retired from building Bajas, Fiberglass Buggies and Rails in the Mojave Desert. Also Sprints & Midgets, Dry Lakes, Road Race cars. All types New and Vintage
SoCalBajas Member
Kicked Cancer's A$$...1st and 2nd round...Fight ain't over yet.

[Benjamingvsu]

I'm also exhaust shopping - how do you attach the muffler to the downturn collector - weld it on? Does it need any support?

[cbeck]

Open and pointed away from me. It's only noisy when you put your foot in it.

_________________
My cut in half and rebuild thread
www.thesamba.com/vw/forum/viewtopic.php?t=647779

[Vanillagurilla]

[Benjamingvsu]

I've also been looking at this style- can you tell me how far it is from the top edge of the bend before the end of the exhaust to the top edge of the pipe it crosses over - trying to figure out if it will fit with where my bumper tubes are.

[cbeck]

I will check tomorrow.
_________________
My cut in half and rebuild thread
www.thesamba.com/vw/forum/viewtopic.php?t=647779

[dustymojave]

[oldschool5er]

This is an example of one of mine with a Tri Mill and U bend with a clamped on Empi can. The Empi can comes with a spark arrester but I leave it off and only put it on if I am in an area that requires it. Putting it on even quiets it down more. It is short enough and light enough that I don't bolt it down but clamping it is a little risky as I can loose it, but I want to run open at times. I went U bend because I kept getting exhaust fumes in the back window when I ran straight up bob cat. I prefer straight open exhaust and just love the sound although most people don't want that. The Empi can takes the edge off. I installed a Turbo Muffler on a customers car as Richard suggests and he is in love with it. One thing is that yes a 1.5" is the best choice for an 1835, but if you ever plan on building a bigger motor you could run a 1 5/8" on it for now and get away with it without any real issues although not a perfect size, but would save you from buying another exhaust if you ever build it bigger.

_________________
HRE in Westerville,Ohio

Full machine shop with all types of CNC. Rapid prototyping available, CNC Plasma cutting, 3D printing and Laser engraving.

[mr_bill]

CUSTOM....1 1/2" "sidewinder w/ equal length tubes & merged collector, from "A-1 Exhaust, in Santa Ana, CA.
_________________
see ya' on the trail........

"Mr Bill"
Dos Perros Motorsports
Orange, CA
1972 Class 11x/Stock Bug
'60's era "vintage" Tunnell-Buggy

"...no one here....get's out ALIVE...."

Motor = electric
Engine = internal combustion

www.facebook.com/groups/DosPerrosMotorsports
www.alrchapter132.org
www.DAV.org

[cbeck]

#2 exhaust tube leaves the port, drops about1.5", and comes 7"out from the head.

The bend between the collector and outlet is 6.5"from top of #2 tube to top of bend. I ended up using purple nail polish to make a timing mark on the bottom of the pulley so my timing lite would lite up a spot I could see the case split. With the hp I think I have(125), I won't miss a few with unequal length tubes.

_________________
My cut in half and rebuild thread
www.thesamba.com/vw/forum/viewtopic.php?t=647779

[dustymojave]

[mr_bill]

have "A-1" exhaust on my 11 car, too.........EXCELLENT items
_________________
see ya' on the trail........

"Mr Bill"
Dos Perros Motorsports
Orange, CA
1972 Class 11x/Stock Bug
'60's era "vintage" Tunnell-Buggy

"...no one here....get's out ALIVE...."

Motor = electric
Engine = internal combustion

www.facebook.com/groups/DosPerrosMotorsports
www.alrchapter132.org
www.DAV.org

[dustymojave]