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Will Cut Outs Improve my E.T? #994805 05/18/11 09:56 AM 05/18/11 09:56 AM
Joined: May 2005 Posts: 128 usa mrmopardan OP member
mrmopardan OP member Joined: May 2005 Posts: 128 usa	I make a occasional 1/4 Mi. pass down the track. I race with full 3 " TTI exhaust with their Dynomax mufflers. This exhaust seems to flow well but I'm wondering if there is even more performance to be had through exhaust modifications. would there be an improvement by adding "cut outs"? Anyone tried this and if so where is the ideal location to install and which brand. Thanks, Danny 68 GTX Full street trim, solid lifter cammed. Best 11.34 @ 121 mph. 1.72 60 ft. (yeah I know.. my 60 ft. sucks)

Re: Will Cut Outs Improve my E.T? [Re: mrmopardan] #994806 05/18/11 10:23 AM 05/18/11 10:23 AM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	un-capped seems to pick up 2-5 tenths depending on system. Since you have a decent 3" I'd guess you'd pick 2 or so. Enought to dip into the 11's I'd think. My old 67 coronet w/ a mild 440 and 2.5 system would drop 3.5 tenths w/ the exhaust open. And before those guys who get on here and claim no difference.. I don't count a 3.5 with a race mufflers and no tail pipes as an exhaust system. If you want to see how much, un-cap the headers and make a blast. That way you'll get an idea. [IMG]http://i66.tinypic.com/pui5j.jpg[/IMG] Coming soon!!!!

Re: Will Cut Outs Improve my E.T? [Re: mrmopardan] #994807 05/18/11 10:24 AM 05/18/11 10:24 AM
Joined: Dec 2004 Posts: 2,703 Mohnton, Pa DodgeCharger master
DodgeCharger master Joined: Dec 2004 Posts: 2,703 Mohnton, Pa	I would doubt it would improve enough that you would notice it. I run a full 3 inch exhaust with magnaflows and if I drop the exhaust I don't really notice much improvement. maybe .05 at the most.

Re: Will Cut Outs Improve my E.T? [Re: mrmopardan] #994808 05/18/11 10:34 AM 05/18/11 10:34 AM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	I am planning a cut out system for my Rampage BUT I will have a header with about 16" long collector and I will come off the side of the collector to run to my exhaust, where most guys run straight off the back of the collector... you would need to jet differently without the exhaust... this is where guys dont see any change due to not jetting for the change... I plan on a split on the jetting... not perfect for either set up, unless it will see alot more street mileage, then I'll jet for the street and the exhaust

Re: Will Cut Outs Improve my E.T? [Re: DodgeCharger] #994809 05/18/11 10:38 AM 05/18/11 10:38 AM
Joined: Jan 2003 Posts: 1,142 Central New York slippery440 Crybaby440
slippery440 Crybaby440 Joined: Jan 2003 Posts: 1,142 Central New York	Same question almost a few days ago. Same answer. We found that if you drop the whole exhaust system off the car you will gain .1 to 1.5 in the 1/4. We guess some or most of that gain was for the lost of weight. You are just adding cut outs. Probly all your going to gain is to the noise pollution. Is it worth the hassel? If you have a totally junk exhaust yes if not no. If the MODS did their job I would not be hitting the notify MOD button. LOL

Re: Will Cut Outs Improve my E.T? [Re: mrmopardan] #994810 05/18/11 11:21 AM 05/18/11 11:21 AM
Joined: Nov 2005 Posts: 690 New Hampshire, USA O oldiron mopar
oldiron mopar O Joined: Nov 2005 Posts: 690 New Hampshire, USA	66 belvedere, 431/tti 1 7/8, 3 in (with tailpipes), dynomax, 4sp, cutouts saw no consistent measureable difference (best 11.07, consistent 11 2s to 3s. Would often run street stick class (closed) and quick stick (open) one after another. Liked the pipes open so I could hear engine revs on shifts (know if clutch slipped), plus I basically like the noise. If anything, slowed down slightly w/cutouts open, ran lean. If carb was jetted properly for open pipes probly would have picked up, but never tried cause I'm basically lazy. 66 Belvedere Vert, 4 Speed/Jerico, slowly, very slowly, getting faster - NA LD Wedge New New Best: 10.56 @129 68 B'cuda 4 gear Jerico - Another New Best of 9.86 & Trying to slow up https://www.youtube.com/watch?v=T4jDLKwd9Gs

Re: Will Cut Outs Improve my E.T? [Re: oldiron] #994811 05/18/11 03:01 PM 05/18/11 03:01 PM
Joined: May 2005 Posts: 128 usa mrmopardan OP member
mrmopardan OP member Joined: May 2005 Posts: 128 usa	As I continue to research this subject.. I also have the oval GTX exhaust tips too. Are they restrictive?? 68 GTX Full street trim, solid lifter cammed. Best 11.34 @ 121 mph. 1.72 60 ft. (yeah I know.. my 60 ft. sucks)

Re: Will Cut Outs Improve my E.T? [Re: MR_P_BODY] #994812 05/18/11 03:23 PM 05/18/11 03:23 PM
Joined: Sep 2004 Posts: 22,873 Chicken coop dustergirl340 Chicken Little
dustergirl340 Chicken Little Joined: Sep 2004 Posts: 22,873 Chicken coop	Quote: this is where guys dont see any change due to not jetting for the change... amen to that! I've picked up 3-4 tenths with open exhaust AND jetting. I once forgot to re-jet when I uncapped and saw no gain, and ran very lean to boot.

Re: Will Cut Outs Improve my E.T? [Re: dustergirl340] #994813 05/18/11 03:35 PM 05/18/11 03:35 PM
Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again Moparnut426 I Live Here
Moparnut426 I Live Here Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again	I have seen guys switch to a more free flowing exhaust and have a slower E.T. and had it run leaner. So there is a lot to just dumping the pipes and goin racing. Kasey

Re: Will Cut Outs Improve my E.T? [Re: Moparnut426] #994814 05/18/11 05:01 PM 05/18/11 05:01 PM
Joined: Jan 2003 Posts: 17,918 Akron, Ohio ProSport I Live Here
ProSport I Live Here Joined: Jan 2003 Posts: 17,918 Akron, Ohio	I ran an X-pipe on my old car with Magnaflows and turnouts in front of the rear tires, it was pretty quiet and ran 9.90 with or w/o the exhaust system. 1970 Challenger, all aluminum 528 Hemi, HDK suspension, Tremec 5 speed manual

Re: Will Cut Outs Improve my E.T? [Re: ProSport] #994815 05/18/11 05:12 PM 05/18/11 05:12 PM
Joined: Jan 2004 Posts: 877 Pittsburgh, Pa J Jeff_383 super stock
Jeff_383 super stock J Joined: Jan 2004 Posts: 877 Pittsburgh, Pa	68LAR went from a 11.60 to a 11.28 just with opening the exahust. No jetting change. He has a full 3" sysytem with dynomax ultraflows.

Re: Will Cut Outs Improve my E.T? [Re: Jeff_383] #994816 05/18/11 05:24 PM 05/18/11 05:24 PM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	Quote: 68LAR went from a 11.60 to a 11.28 just with opening the exahust. No jetting change. He has a full 3" sysytem with dynomax ultraflows. I think I was the winner of the "how much faster" contest on that one.

Re: Will Cut Outs Improve my E.T? [Re: DodgeCharger] #994817 05/18/11 07:47 PM 05/18/11 07:47 PM
Joined: Jan 2003 Posts: 3,943 Melbourne.....Oz-land Moparmal master
Moparmal master Joined: Jan 2003 Posts: 3,943 Melbourne.....Oz-land	Quote: I would doubt it would improve enough that you would notice it. I run a full 3 inch exhaust with magnaflows and if I drop the exhaust I don't really notice much improvement. maybe .05 at the most. Same deal - Magnaflows with twin 2.5" and X pipe. I have electric cuot outs, I open them at the track and tune one stage richer and no difference. If I don't tune one stage richer it leans and I go slower. Thats the benefit of maganflows - they actually flow. 67 RO23 clone with 6.1 SRT Hemi and dual quads. Soon to have Drag Pak induction and Throttle body.

Re: Will Cut Outs Improve my E.T? [Re: mrmopardan] #994818 05/18/11 08:18 PM 05/18/11 08:18 PM
Joined: Jan 2003 Posts: 5,894 Florida Locomotion master
Locomotion master Joined: Jan 2003 Posts: 5,894 Florida	A lot depends on how the carb is jetted. Typically, ideal jetting for a closed exhaust will be lean for an open exhaust. Of course, the more cubes and rpm's you have, will also be a factor, so the results depend on how efficient the exhaust is compared to the amounbt of air/fuel you're putting through it. I've been running TTI step headers on my 360 for years and had the carb tuned for it as best as I could. A few years ago I installed a 3" x-pipe and Dynomax Ultra Flo mufflers (oval) ending at the rear end housing. After some carb tuning which I believe included dropping the jet sizes 1-2 numbers and getting the weight back to what it was (system was +60 lbs), the car was about .5-.10 faster than open headers! I can only assume that the x-pipe affected the jetting, overall helped my particular combination and that the mufflers were not a restriction. Last edited by Locomotion; 05/18/11 08:27 PM.

Re: Will Cut Outs Improve my E.T? [Re: MR_P_BODY] #994819 05/18/11 09:18 PM 05/18/11 09:18 PM
Joined: Nov 2009 Posts: 2,275 Desert Tracker H HYPER8oSoNic top fuel
HYPER8oSoNic top fuel H Joined: Nov 2009 Posts: 2,275 Desert Tracker	Quote: I am planning a cut out system for my Rampage BUT I will have a header with about 16" long collector and I will come off the side of the collector to run to my exhaust, where most guys run straight off the back of the collector... you would need to jet differently without the exhaust... this is where guys dont see any change due to not jetting for the change... I plan on a split on the jetting... not perfect for either set up, unless it will see alot more street mileage, then I'll jet for the street and the exhaust "Stupidity is Ignorance on Steroids" "Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)

Re: Will Cut Outs Improve my E.T? [Re: slippery440] #994820 05/18/11 10:32 PM 05/18/11 10:32 PM
Joined: Oct 2008 Posts: 261 Wisconsin BLONDE BARRACUDA enthusiast
BLONDE BARRACUDA enthusiast Joined: Oct 2008 Posts: 261 Wisconsin

Re: Will Cut Outs Improve my E.T? [Re: Mr.Yuck] #994821 05/18/11 10:39 PM 05/18/11 10:39 PM
Joined: Jan 2003 Posts: 12,141 Benton, IL. D DaveRS23 Special needs idiot
DaveRS23 Special needs idiot D Joined: Jan 2003 Posts: 12,141 Benton, IL.	Quote: un-capped seems to pick up 2-5 tenths depending on system. Since you have a decent 3" I'd guess you'd pick 2 or so. Enought to dip into the 11's I'd think. My old 67 coronet w/ a mild 440 and 2.5 system would drop 3.5 tenths w/ the exhaust open. And before those guys who get on here and claim no difference.. I don't count a 3.5 with a race mufflers and no tail pipes as an exhaust system. If you want to see how much, un-cap the headers and make a blast. That way you'll get an idea. My car picks up about .2 with them open. And I agree that testing with the exhaust open at the track will tell you what you need to know. Because there is a car show most weekends around here, I hit a couple a month. Which means the car sees more show time than track time. The cut-outs are more fun at car shows than they are at the track. I have cops come by and ask me to open them up and fire it up. Cut-outs are just tons of fun on the street! The added performance at the track is gravy. Master, again and still

Re: Will Cut Outs Improve my E.T? [Re: DaveRS23] #994822 05/19/11 02:04 AM 05/19/11 02:04 AM
Joined: Jul 2006 Posts: 4,319 Puyallup, WA S StealthWedge67 master
StealthWedge67 master S Joined: Jul 2006 Posts: 4,319 Puyallup, WA	When I bought my car it had a fairly new exhaust sytem with Flowmasters on it, but it was 2-1/4" pipe. So I added about 18" of 3" pipe off the headers (to get past the subframe) leading to a set of 3" cutouts, then it steps down to 18" of 2-1/2, and then down to the existing 2-1/4" setup. I see a solid .25 when open, but my system is relatively restrictive compared to a full 3" system. To make it pay, you really need to rejet LemonWedge - Street heavy / Strip ready - 11.07 @ 120

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