datzenmike Posted August 31, 2014 Report Share Posted August 31, 2014 Putting my exhaust back in and it pains me. The thing is crazy rusty. Should I cut off the down pipe, blast it, and paint?? Seems like a bad idea , but fucking rusty ass pipe messing up the theme. I like the stock manifold, so headers are out. So I do need to work with the stock down pipe that brings two to one. I presume making a custom one would be more bs than I want. I don't know. I do know that sound means nothing to me. Quiet is what I want in my muffler, though performance is still a consideration. I'd love muffler recommendations, and suggestions on making the plumbing look right. Paint? More like ceramic coating to handle 700 -800F. No-one will see or care about rust and you shouldn't too Get one of the exhaust flanges modeled on the gasket and run dual 1.75s Someone makes it? Mklotz does. www.bluehandsinc.com Mike's flange hole is 42.6mm or 1 43/64ths so a 1 5/8" pipe will fit. Two 1 5/8" pipes will have the same cross sectional area as a single 2.3" pipe. As the stock 510 pipe is likely no larger than 1 3/4" this is a huge increase. The factory saw fit to join these two pipes into a single smaller pipe to keep the exhaust speed up.... and it's cheaper. You could run two 1 1/2" pipes which would equal a 2 1/8" single exhaust pipe. Smaller pipes will fit easier than larger. The mufflers will also be smaller and easier to place. Link to comment
laotsu Posted August 31, 2014 Author Report Share Posted August 31, 2014 I've had pretty knowledgeable exhaust guys say not to go larger than 2.25". Link to comment
tr8er Posted August 31, 2014 Report Share Posted August 31, 2014 Like this? Only smaller pipe? The thread from 2010, can't find it off hand, said they lost low end torque. This due to loss of back pressure. I wonder if 1.5" would be even better in duel? I'm not one who needs big pipe to get off. And yes. I would know to go ceramic. But all I would have reasonable access to would be spray able ceramic. I've got no powder coat guy out here. Link to comment
datzenmike Posted August 31, 2014 Report Share Posted August 31, 2014 I don't think it's back pressure. You want the smallest pipe to give the fastest gas speed but not so small that it becomes restrictive. A tall order I know. A fast gas speed has more inertia. It travels so fast that it sucks all (or more) of the exhaust out of the cylinder. In fact at times it can actually begin to suck in the intake air during the overlap times when both valves are open. This reduces the engine having to do the work of pushing exhaust out and sucking air in. A huge exhaust pipe only approaches this when at extreme RPMs with lots of flow. At low speed more exhaust is left in the cylinder and has to be pushed out or it dilutes the intake air. A turbo would be an exception as huge amounts of exhaust are produced and can be run in a larger pipe yet still have good speed. A 2" pipe will flow 4 times what a 1" pipe will so you don't need a big increase in size. Link to comment
RatVonDude Posted August 31, 2014 Report Share Posted August 31, 2014 last time someone mentioned "back pressure" they got thrown to the lion, apparently it doesn't help an engine. exist 1.75 straight and yoshermurer cherry bombs <<< "boss man " Link to comment
tr8er Posted August 31, 2014 Report Share Posted August 31, 2014 Cherry bombs are too loud. If my engine sounded like a Tesla, but still runs like my Datsun, I'd be happy. Is there a higher functioning (muffling) muffler that anyone can recommend? And I'm still only considering duels. Once I choose my path, I'll move this to my build. Thanks Link to comment
tr8er Posted August 31, 2014 Report Share Posted August 31, 2014 I put a flow master on my Z in the 90's. Hated the loud. Made me feel like the Civics I wanted to monkey stomp. And I was not a Camero, who, at the time I felt deserved the straight pipe sound. Link to comment
Trophy24 Posted August 31, 2014 Report Share Posted August 31, 2014 Use the cherry bomb in combination with another muffler. I know this will add to the cost, but you are already running dual pipes and it will therefore not be the cheapest route. I see this design at work every day with quiet sound levels. Link to comment
laotsu Posted August 31, 2014 Author Report Share Posted August 31, 2014 I like the Thrush glasspack I use but I have no idea if it'll be too loud for you. Link to comment
tr8er Posted August 31, 2014 Report Share Posted August 31, 2014 Use the cherry bomb in combination with another muffler. I know this will add to the cost, but you are already running dual pipes and it will therefore not be the cheapest route. I see this design at work every day with quiet sound levels. So, in this setup, what does the Cherry Bomb do for me? Link to comment
RatVonDude Posted August 31, 2014 Report Share Posted August 31, 2014 Cherry bombs are too loud. If my engine sounded like a Tesla, but still runs like my Datsun, I'd be happy. Is there a higher functioning (muffling) muffler that anyone can recommend? And I'm still only considering duels. Once I choose my path, I'll move this to my build. Thanks somebody was talking how there scored twin yoshimura motorcycle exhausts of c.list for $150.00 and put em on a 1600. I would think the sound would be nice and tame. Link to comment
tr8er Posted August 31, 2014 Report Share Posted August 31, 2014 Clarifying statement: "only considering duels", meaning, I'll likely have a single exhaust, but am considering duel. Link to comment
smoke Posted August 31, 2014 Report Share Posted August 31, 2014 I was the one who will throw you in a pit for even using the word backpressure. But anyway...just use a turbo style muffler, a bigger one will make it quiet. 1 Link to comment
tr8er Posted August 31, 2014 Report Share Posted August 31, 2014 I've found that back pressure can really reduce turbo lag... But no, velocity without friction will create vacuum on the valve overlap reducing piston work. Sucking exhaust fumes from cylinder. Increasing combustible mix in cylinder. Increasing efficiency of engine. I do get it. Back pressure is one step past high velocity, and into friction. For my purposes, I'd want highest performance in the 45-70mph range. Link to comment
HRH Posted August 31, 2014 Report Share Posted August 31, 2014 Since I got the new wheels and tires on ugly Betty, I decided I didn't need my turbines anymore. I love those wheels, but I've been helping out a kid from Saudi Arabia who's been coming into NAPA quite a bit working on his '73 610. He's a student up at EWU. Think he's transferred to another school in Lewiston or something now, can't remember. Anyway, just goes to prove all middle easterner's can't be bad. He loves this 610. It looked pretty pitiful to start with, but he's been doing a lot of work on it. Converted it to a Weber carb, got the engine running right a month ago. We had to fix a lot of vacuum leaks. Anyway, I sold him the turbines today along with some 280zx struts I had cluttering up the garage. They make the 610 look waaaay better. Now to clean the garage and start working on the motor for Gracie II. Red truck needs to have the motor swapped before the snow flies! 1 Link to comment
flatcat19 Posted August 31, 2014 Report Share Posted August 31, 2014 Was that 610 hidden in Pasco? I know where one exactly like that was-drove by it a few weeks ago-GONE! That car is so ugly its beautiful. Link to comment
HRH Posted August 31, 2014 Report Share Posted August 31, 2014 I'm not sure where he picked it up, but it might have been Pasco. Body-wise, it's a great find, very little rust. I actually like the shape better than the 510, though I think it needs fender flares and 16s to make it just right. Link to comment
datzenmike Posted August 31, 2014 Report Share Posted August 31, 2014 I put a flow master on my Z in the 90's. Hated the loud. Made me feel like the Civics I wanted to monkey stomp. And I was not a Camero, who, at the time I felt deserved the straight pipe sound. Avoid any straight through design. Turbo style use baffles and fiberglass lining to absorb the initial shotgun blast of the exhaust pulse. Take the raspy snap out of it. I would run stock mufflers. Only two cylinders using it so half the backpressure restriction... win win. Link to comment
flatcat19 Posted August 31, 2014 Report Share Posted August 31, 2014 I'm not sure where he picked it up, but it might have been Pasco. Body-wise, it's a great find, very little rust. I actually like the shape better than the 510, though I think it needs fender flares and 16s to make it just right. Been drooling over that car for a few years. I always thought it was hidden well enough that I could go get it anytime. Link to comment
tr8er Posted August 31, 2014 Report Share Posted August 31, 2014 Walker quiet flow muffler? Link to comment
smoke Posted August 31, 2014 Report Share Posted August 31, 2014 Yes, I think you would like that. Link to comment
HRH Posted September 1, 2014 Report Share Posted September 1, 2014 And the ratsun circle has completed itself. Since I sold the turbines to Mohammed, I started turning my attention to the red truck. Didn't get anything done on the motor for it today, but I have been needing a set of extra wheels so I don't have to keep swapping winter and summer tires on the 5 spokes. So I searched for turbines on craigslist, and I just got back with these :) Link to comment
thisismatt Posted September 1, 2014 Report Share Posted September 1, 2014 Unless your two exhaust pipes are fighting each other over multiple confrontations, they're duals, otherwise they're duels. 1 Link to comment
laotsu Posted September 1, 2014 Author Report Share Posted September 1, 2014 unless you are a Nazi, you are an internet forum spelling cop... :devil: 1 Link to comment
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