pauldana

The 3" filter will work, and is much better..

Those headers do not look like shorties.. ??

KNOT-HEAD

Thanks...
I know, it's time to man up and quit being a cry baby. Understand, I'm just an old fat man looking for sympathy. I usually get it too! Except from "pauldana"..... cus-he's just an old grouch! I was just kidding. I can't wait to fire that puppy up. I think I may wear a double pair of heavy duty night time "Depend's", if and when the opportunity arrives.
I just spoke to the mechanic working on the car at about 10:00am this morning. My opening statement to him when he answered the phone with "hello" went something like this: "Good morning! Before you have the opportunity to ruin my weekend, please let me tell you how much potential you have to do so! Last week I hoped and prayed my wife and myself would be able to drive the car to Crusin The Coast. As you know, a critical part for the new transmission had been overlooked and was not delivered in time to meet that schedule. WELL!!! This Saturday (tomorrow) the company I am employed by is having a big shindig on the LSU campus by means of a tail gate party. All the high mucky-mucks in the company and client base will be attending. It would really lift my spirits to heavenly heights if I would be able to drive up to that company function, push the switch on those electric cut-outs and blow the socks of all those VP's. Now, am I going to be able to do that? The answer was.... I'm waiting for the shortened driveshaft to make it back from the machine shop. I said "Can you light a fire under his *** and get it here soon enough? He said he had already discussed that situation with him. So, If you are a praying person....Put me on your prayer line so this two year curse will lifted from my solders (and bill fold). The saga continues!

KNOT-HEAD

pauldana

The exhaust may very well decrees your overall power output RWHP.. louder and slower they are... A proper exhaust system uses scavenging and the cutouts do not... it would be better to take the money and make an X pipe..

KNOT-HEAD

Thanks,
After all the good advice you and others have consistently shared with me, I didn't want to take a chance this late in the game and underestimate the final installation height of the intake, carb, breather assembly, so I just ordered the 2" replacement (for the same reason God put nipples on a man.....JUST IN CASE...LOL!) I still haven't gotten the car back. The yoke the machinist ordered for the shortened driveshaft was the wrong one to fit the 700r4 transmission. Once I get the car in hand, I will try the 3" filter to make sure it will fit and not allow the top of the breather to rub on the heat fire protection on the inside of the hood.
Yes, The headers are not "shorties" they are the mid-length (see attached). I know they are not as efficient as "tuned full length" but they will have to do.

KNOT-HEAD

KNOT-HEAD

Alright pauldana... You are driving me crazy. You have beat me to a pulp about the "mid-length" headers I have... Now you want to throw "X-pipes" at me...What the hell is "X pipes"? The original exhaust brought the original exhaust manifold to the pipe than made a single "Y" through the chassis than back to duel pipes before the muffler. I had the muffler shop make it a true duel exhaust coming straight from the "mid-length" headers to a true duel exhaust. Should I have left the "Y" to allow for more back pressure and scavenge more exhaust?

KNOT-HEAD

cv67

You dont need a X or H pipe, do whats best for you!
Unless you have a horrible exh port its a waste.

DAD111

Agreed - dont worry about exhaust at this time, Get that hot rod up and running and have some fun, then worry about fine tuning it.

KNOT-HEAD

Thanks cuisinartvette,
I just think "pauldana" is grouchy old man (like me) that get's his jollies by beating up (ignorant, stupid, gullible, self destructive, crybaby, KNOT-HEAD'S) sweet old men like me!...LOL! I am very sure he looks forward to seeing what NEW stupid mistake I have made, so he can "toot his own horn" and make me more unmissable than I already make myself..... Just kidding. All of you have been a blessing. Please keep up the "charity work". I know I will never be able to give any of you good advice about automobiles and/or the internal combustion engine but I do pass what I learn from you to others when given the opportunity.
Now, I can educate you on the miracle effects of Food Grade Hydrogen Peroxide and Medical Grade D.M.S.O. (Dimethyl Sulfoxide).
KNOT-HEAD

KNOT-HEAD

OK, pauldana....
Let's get fa-reel-up-in-hya!
We already discussed the fact that I NEVER plan to race this car either on the street or strip but I would like to have some credibility when around knowledgeable enthusiast, such as yourself. Now that's another thing, after I die and my thrill seeking eldest son inherits the car...all bets are off.
What am I actually sacrificing by not having all the bells and whistles? How much horse power? How much efficiency? How much speed? How much anything? I'm starting off with a 485hp engine. I know I am loosing (bla, bla, bla) from the engine to the ground because of additional strain put on the engine by the auxiliary (A/C, power steering, water pump, alternator... etc.) equipment. How much do you think (all the good stuff) will drop because of not using the most effective engine and exhaust components?

KNOT-HEAD

KNOT-HEAD

pauldana

Exhaust...her is the scoop...

Larger tubes obviously flow better... but there is a point of diminishing returns,,, And there is a thing called scavenging.. Thus the right size pipes for the engine being used. In my case 2" primaries are best, but I went 1 7/8" for fitment.. in your case 1 5/8" would be best. The "tuned" headers like mine help a bit more with scavenging... a H or X pipe, X-pipe being better, helps even more
with scavenging... To give you a reference, the corvettes here that run side pipes rather than a tuned exhaust loose on the Dyno around 15hp-30hp.. depending on the engine.
A tuned x-pipe will also give a different sound, more of a modern higher pitched sound with a LOT less drone. So you would loose the "motor boat sound" some people feel is more of a "muscle car sound"

https://en.wikipedia.org/wiki/Scavenging_(automotive)
scavenging (automotive)

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Not to be confused with Scavenge pump.This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (September 2015)(Learn how and when to remove this template message)
Uniflow scavengingIn automotive usage, scavenging is the process of pushing exhausted gas-charge out of the cylinder and drawing in a fresh draught of air or fuel/air mixture for the next cycle.

This process is essential in having a smooth-running internal combustion engine. If scavenging is incomplete, the following stroke will begin with a mix of exhaust fumes rather than clean air. This may be inadequate for proper combustion, leading to poor running conditions such as four-stroking. If scavenging is not properly done it will affect the total power output of the engine.

Scavenging is equally important for both two- and four-stroke engines. However it is more difficult to achieve in two-stroke engines, owing to the proximity, or even overlap, of their induction and exhaust strokes. Scavenging is also equally important to both petrol and diesel engines.

KNOT-HEAD

Thanks,
I get the reason for the scavenging. The picture was a great help. So the air/fuel mixture is compressed then ignited at the top of the compression stroke, driving the piston down and turning the crank shaft. The next piston fires bringing the first piston back toward the compression stroke. If you are pulling in a fresh mixture of air/fuel at the same time you are exhausting the spent mixture any mixture not ignited will be trapped in the cylinder and become part of the new fresh mixture. Right?

What is an "X & H" pipe? I am assuming the crossover pipe between the exhaust manifold and the muffler I originally had on the car would be considered an "X" pipe! Right? If so, I should have left the crossover pipe instead of changing it to "true duel" exhaust! Right?

The side pipes allow for less back pressure and allow a smooth exhaust release. If that release is not balanced you will loose power on the compression stroke allowing some mixture not to be properly absorbed by the piston and transferred to the crank shaft. Right?

KNOT-HEAD

pauldana

Scavenging.... When the exhaust blows out of one piston hole "a pulse" of hot expanding exhaust gas is produced that traveled down the header tube. This pulse crates a vacuum behind it, if the pulses from the other tubes come in a a tuned length (all same length tubs) the pulses will be one in back of the other, each pulse helping move the pulse behind it by the vacuum created. .... now, go further down the main tubes to a "X-pipe" a pipe that crosses over in an "X" format to the other side and connecting the 2 exhaust pipes together, these pulses then mix and in a tuned manner to help produce even greater scavenging thus increasing HP. This type of exhaust is used on all new modern performance cars. Thus the loss of that "muscle car sound" but increasing HP and fuel economy. An H-pipe does not intersect in an "X" pattern and usual has a pipe welded from onside to the other, it is not as efficient as an x-pipe.

Side pipes ,,, Read above.

KNOT-HEAD

Thanks,
So naturally... I had it backwards. Scavenging helps pull the hot air out of the cylinders. Tuned headers equal up the suction. Good thing I don't do this for a living.

KNOT-HEAD

jb78L-82

That was Funny...^^^^^^^^^^^^

DAD111

The X pipe he is referring too is after the headers - small section of straight pipe then the x crossover, just about where your cross-member for the trans is located. Goggle exhaust systems for C3 vettes. For the best power HP gains on your motor this would be a good choice. Add another $1000.00 to your list. The exhaust system you have will do fine - maybe 15% to 20% HP loss. By the seat of the pants you will never feel the difference. Dyno you will see a difference because it's a graph..

pauldana

KNOT-HEAD

Thanks,
It's a big difference between "funny" and pitiful! I'm trying to learn all this mumbo-jumbo high tech jargon and will never use it! I'm gonna impress the hell out of some of those little old ladies at the car show that come remissness about "the good old days", trying to get in and out of their boyfriend's car ("OH! It looked just like yours"), while "not" showing too much (lady parts) satin and lace, under their mini-skirt
Hopefully their husbands will know LESS than I do so I can baffle them with bull s**t.

All joking aside. I don't know how much, if any, of this thread you have followed. These EXPERTS have had a great deal of patience with me TRYING to keep me from continuing my two year battle with my attempt in cutting cost over "do it right the first time". Even "pauldana" is NOT beating up on me as much anymore. That's a miracle in it's self!

KNOT-HEAD

P.S.
I still don't have the car. Don't know why...this time... but I'm not going to ask! I missed Crusin The Coast, the company LSU vs Georgia tail gate party. I'm hoping I can have it for our company "breast cancer awareness" benefit tomorrow...just have to keep my fingers crossed. I have never driven a 400(+)hp car before. Gonna be like a kid on Christmas!

KNOT-HEAD

Thanks,
Just add that to the list of screw ups. That is basically what the original exhaust was like. Two individual pipes, connecting to one pipe where it penetrated the cross member of the chassis, then back too two pipes that connected to two mufflers. I didn't know why they did "such a stupid thing" so when I had the mid length headers and electric cutouts installed I had them go "true duel exhaust". Oh well!!!!!

KNOT-HEAD

DAD111

That will work just fine - True duels

pauldana

True Duel you have is much better than the stock "Y" exhaust.