Pinto Car Club of America

Shiny is Good! => Your Pintos/Bobcats & Racers => Topic started by: EP73Pinto on September 02, 2007, 10:52:22 PM

Title: Exhaust, how much is too much?
Post by: EP73Pinto on September 02, 2007, 10:52:22 PM
I have a mildly built 2.0. It has four 38mm Mikuni side drafts, a Racer Walsh (RW) #2 cam, and about 11:1 comp. I also bought a Schoenfeld header from RW. The header has 1 5/8" primary's that step to 1 3/4 and meet in a 3" collector. I asked the people at RW if a 2 liter pinto can flow a 3" exhaust. They assured me that the circle track guys run this exhaust open and that if I am running a full length pipe (over the axle and out the back) with a muffler that 3" would not be too much. This car is a former F Production road race car (ICSCC) and will be used for auto cross. Therefore I will need plenty of mid range torque. I am thinking of stepping it down to a 2.5" or a 2.25". Any suggestions? Any body run a N/A pinto with a 3" exhaust?
Also the cam grind is: Lift  .450", Dur @ .050" - 245/252. Anybody have a suggestion on a cam that might be better for my application? Thanks.
Title: Re: Exhaust, how much is too much?
Post by: Pintony on September 03, 2007, 02:14:08 AM
Hello EP73Pinto,
I think U will find that the Schoenfeld header will NOT clear the 2.0 motor mount on the passenger side...
Also, U will NOT be able to get 3" exhaust around the axle it will have to go under...

From Pintony
Title: Re: Exhaust, how much is too much?
Post by: 77turbopinto on September 03, 2007, 12:06:38 PM
"Too much" is only defined with you YOUR GOALS for the car.

Keep in mind that circle track racecars are driven in a different manner than on the street (or as least they should be) or auto-x, and that a race set up might make street driving or auto-x an issue.

Bill
Title: Re: Exhaust, how much is too much?
Post by: Pinturbo75 on September 03, 2007, 12:24:19 PM
sorry to disagree, but, i have 3" all the way to the bumper and its over the axle. sam, AKA the whistler on turboford has 3.5 all the way to the bumper over the axle. i did mine with mandrel bends for about 70 bucks plus the muffler at 55 bucks. i can post pics if you need.
Title: Re: Exhaust, how much is too much?
Post by: crazyhorse on September 03, 2007, 01:25:11 PM
Just remember, Pintony likes his cars LOW. He may well not have room for a 3" exhaust.
Hope I'm not steppin on your toes Pintony.
@stock height I can't see a prob with a 3" exhaust over the axle.
Title: Re: Exhaust, how much is too much?
Post by: Pintony on September 03, 2007, 03:10:32 PM
Quote from: 4CAMMER72 on September 03, 2007, 12:24:19 PM
sorry to disagree, but, i have 3" all the way to the bumper and its over the axle. sam, AKA the whistler on turboford has 3.5 all the way to the bumper over the axle. i did mine with mandrel bends for about 70 bucks plus the muffler at 55 bucks. i can post pics if you need.

Hello 4CAMMER72,
I would like toi see the photos...
From Pintony
Title: Re: Exhaust, how much is too much?
Post by: UltimatePinto on September 04, 2007, 12:07:44 AM
I can say from experience that Pintony is right about the motor mount issue. Had to relocate the mount on my Runabout install.

My Schoenfield came with a modified mount/bracket that could have been used but it was all steel no rubber.

Trouble with that is you can't hear yourself think with all the engine noise generated with the solid mount. Had a set of solid aluminum mounts purchased from RW years ago. Will never use again.

Al
Title: Re: Exhaust, how much is too much?
Post by: EP73Pinto on September 05, 2007, 01:23:04 AM
Actually I have a 3" exhaust already installed. It is all mandrel bent and it go's up over the axle. And my car is LOW.  :coolafro: (I  don't think I can drive over a pack of cigarettes with my 20" race tires.)  I paid $180 for my aluminized tubing.  :-\ I cut and fit it myself. Took all day just to do that. And you're right about the Schoenfeld header not clearing the motor mount. I made a custom mount to get around it. I plan on posting pictures soon. I can throw in a couple of pics of the exhaust as well. I'm actually pretty proud of the fit of the exhaust since I'm not a fabricator by trade.
I'm thinking the exhaust might be too big because I don't feel like I have enough midrange. Maybe I've just been spoiled by the 170 ft/lbs that my e30 BMW makes at 3000.
The reason I brought up the cam is I'm not real impressed with the top end either. The power starts dropping off below 6k.
As far as the street drivability, this is a purpose built road race car. No interior (except 2 race seats), and a full cage. I could deal with a difficult car on the street, if it goes like a raped ape on the auto cross. But that gets back to my original post.  I want 200 hp with good power throughout the power band. Any suggestions?
Title: Re: Exhaust, how much is too much?
Post by: Pintony on September 05, 2007, 01:40:36 AM
TURBO
Title: Re: Exhaust, how much is too much?
Post by: 77turbopinto on September 05, 2007, 03:41:04 AM
"200 hp with good power throughout the power band"

I assume you mean that you want a flat torque curve from idle to 6k or so?

Trying to get a N/A engine to a level anywhere near that will take lots time and money. You might not get close to your goals, and the only way to find out is to do it.

I agree with Pintony, for 200HP and a flat-ER torque curve, go with a turbo. From what I have seen, high HP (150+up) N/A 2.0 and 2.3 engines don't have much bottom to upper mid-range power, if any.

IMHO: A good Auto-x car is good as a d/d.

Bill
Title: Re: Exhaust, how much is too much?
Post by: crazyhorse on September 06, 2007, 08:18:33 PM
Quote from: 77turbopinto on September 05, 2007, 03:41:04 AM

IMHO: A good Auto-x car is good as a d/d.

Bill

I TOTALLY agree. if it drives & handles well, it will be an absolute BLAST on the street. I also agree that 200HP from an N/A 2300 is going to be difficult at best. At least if you want it streetable. My goal was always 1hp/cu-in, or 140hp. I think a mild cam & some porting could achieve this reliably.
Title: Re: Exhaust, how much is too much?
Post by: EP73Pinto on September 09, 2007, 11:49:06 PM
Quote from: Pintony on September 03, 2007, 03:10:32 PM
Hello 4CAMMER72,
I would like toi see the photos...
From Pintony
Here is my 3" exhaust. It has a 5" super trap.
I supported the car from the spring perches to show what it looks like with the suspension compressed.
Title: Re: Exhaust, how much is too much?
Post by: EP73Pinto on September 10, 2007, 12:04:24 AM
Here is a picture of the ground clearence. That is a golf ball used for reference. You can dee where the exhaust got partially crushed when I was trying to load it on to a trailer.
Title: Re: Exhaust, how much is too much?
Post by: Pintony on September 10, 2007, 12:22:04 AM
Hey EP73Pinto,
I stand corected!!!!
Title: Re: Exhaust, how much is too much?
Post by: EP73Pinto on September 11, 2007, 11:00:24 PM
Quote from: 77turbopinto on September 05, 2007, 03:41:04 AM
...

IMHO: A good Auto-x car is good as a d/d.

Bill

??? d/d??
Title: Re: Exhaust, how much is too much?
Post by: 77turbopinto on September 12, 2007, 06:51:00 AM
Demo Derby! J/K!! Daily Driver.

Bill
Title: Re: Exhaust, how much is too much?
Post by: Srt on October 08, 2007, 04:40:04 AM
Quote from: EP73Pinto on September 09, 2007, 11:49:06 PM
Here is my 3" exhaust. It has a 5" super trap.
I supported the car from the spring perches to show what it looks like with the suspension compressed.

and the interferance between the pipe and the axle tube is apparrent.  if the guy wants mid range big stuff won't help.  if you're running the car on the street the banging and rattling will drive you crazy
Title: Re: Exhaust, how much is too much?
Post by: Pinturbo75 on October 08, 2007, 04:35:07 PM
the only time i get a clank from the exhaust hitting is when i drop the clutch from over 4500 rpm :D  and that wont happen anymore after i do a few upgrades to the rear suspension.
Title: Re: Exhaust, how much is too much?
Post by: Srt on October 09, 2007, 05:18:38 AM
ok
Title: Re: Exhaust, how much is too much?
Post by: Mutant pony on December 31, 2007, 06:07:40 PM
It sounds to me like you are pretty close. I think the cam is a little on the small side. Racer Walsh should be able to give you a good recomendation on that. With a milled head, good porting, The right cam, your intake and header you should be right around 200hp.
I just read your other post, Yeah, you should be really close.








Title: Re: Exhaust, how much is too much?
Post by: turbo toy on January 01, 2008, 08:57:41 AM
The biggest problem I have with this setup is the 1 5/8" -1 3/4" stepped header. The large primaries are entirely too big for anything but a true race engine and are going to kill low and midrange torque.