Stock exhaust manifold?

Vinyl66 · February 28th, 2008, 08:50 PM

ive tried my best to accurately est. the fly hp of my 302 using Dyno2000 ver. 3.06 program. and with it set up as stock exhaust manifolds w/ mufflers it was showing me making 268hp at 5500 rpm then changing it to small tube header w/ mufflers it was showing me making 315hp at 5500rpm. does that sound crazy or does it make that much of a difference 47hp? i am planning on installing tri-y headers so i figure they would be small tube.

Vinyl66 · February 28th, 2008, 09:47 PM

another question about the est. is with the combustion chamber at 54.58cc it has the compression ratio at 12.50 sound right?

460brevill · February 29th, 2008, 09:47 AM

i dont think headers will give that much extra hp,and that comp. cant be right?

Vinyl66 · February 29th, 2008, 09:52 AM

Originally Posted by 460brevill

i dont think headers will give that much extra hp,and that comp. cant be right?

ive looked and ive heard other people say they have had 35hp jumps in power over manifolds. and as for the comp if i set it for 10.5 it est. the combustion chamber at 63cc and i am pretty sure i have the 54cc head 289s

460brevill · February 29th, 2008, 10:59 AM

what piston are you running?

Vinyl66 · February 29th, 2008, 11:21 AM

Originally Posted by 460brevill

what piston are you running?

just stock and thats how i have it set up on the program. 302 w/ .030 bore 306ci i went through and input all the flow specs for the 289 heads. then it asks for compression ratio and at 12.5 it est. a 54 cc chamber which i believe i have and if i lower it to 11 or 10 i can't remember it est. 64 cc chamber.

460brevill · February 29th, 2008, 11:29 AM

on performance counts dyno,try y over stock gave us 26 extra hp,with short stroke and stock pistons i we are comeing up with 1105 at .030 over.

Vinyl66 · February 29th, 2008, 11:46 AM

Originally Posted by 460brevill

on performance counts dyno,try y over stock gave us 26 extra hp,with short stroke and stock pistons i we are comeing up with 1105 at .030 over.

program or a real dyno?

460brevill · February 29th, 2008, 01:03 PM

real dyno

Vinyl66 · February 29th, 2008, 01:52 PM

hmmm... i wonder what is a better est. then. 54cc (which i have) @ 12.5comp = 315hp or 64cc @ 10.5comp= 297hp

Vinyl66 · February 29th, 2008, 07:07 PM

alright i keep playing with the program and found i have my valves at the wrong diameter and i calculated the comp wrong. now with it set at 10.85 comp i am making 267hp @ 5500rpm on manifolds. with small tube headers i am making 316hp @ 5500rpm. still jumping like crazy but if that happens for real i won't mind

but, i think ive got it pretty much 100% dialed in except exact cam specs but i feel im close on those numbers

MustangOne · March 7th, 2008, 09:46 PM

See if this helps any. We use hedman headders. Fit alot better than tri y's and are only 149.00 and the Coated ones are 279.00 in summit. and fit and look great.
stock set up is 9.5:1 with the 54 cc heads. at 12.5 93 octane gas almost works

460brevill · March 8th, 2008, 09:09 AM

most people on here dont like headmans.i have been useing them for 30 years and love them.i do a lot of the shortys on the mid 80s and up.easy fit and good power adder.

Vinyl66 · March 8th, 2008, 10:56 AM

whats the reasoning that people don't like them? and is it better to go with collector diameter for you exhaust match? IE those headers have a 3 inch collector so would 3 inch exhaust be the optimal fit?

Vinyl66 · March 8th, 2008, 11:12 AM

because i wanted to put these on. Flowmaster

MustangOne · March 8th, 2008, 11:17 AM

I Love Hedman headders. They fit with out dinging and have greater flow than tri y's.

The last 2 sets of tri y's we had to ding both sides at the back of the shock towers

Vinyl66 · March 8th, 2008, 11:47 AM

Originally Posted by MustangOne

I Love Hedman headders. They fit with out dinging and have greater flow than tri y's.

The last 2 sets of tri y's we had to ding both sides at the back of the shock towers

have you tried to put a set on a 64-66 mustang or just your 68? because the 68s have larger engine bays

MustangOne · March 8th, 2008, 01:23 PM

I have put 2 sets on 1965 and 1 set on a 1966. Fit great Look good. Love the price.

My Neon Green 1965 have them and my 1965 GT Conv have them. And Intalled them on a Customers 1966 coupe with 4 Speed. Had zero problems.

460brevill · March 8th, 2008, 11:11 PM

put the headmans on 65/66 with 2 1/2 inch to flowmasters and out the back.you cant go wrong.

jspagna1 · March 9th, 2008, 12:39 PM

I've never had issues with the Tri-Y's. This is mu 2nd Mustang with them. I did get ceramic coated one this time. The rest of the exhaust is 2.5" all the way out the back with H-Pipe & 40 Series Flows. As for the Try-Y's having smaller tubes, it's called more torque, which IMO win's races.

February 28th, 2008, 08:50 PM	#1
Vinyl66 Anatidaephobic 1966 Vinyl Mustang 2012 Hyundai Elantra GLS Join Date: Sep 2007 Posts: 2,353 iTrader: 0 reviews	Stock exhaust manifold? ive tried my best to accurately est. the fly hp of my 302 using Dyno2000 ver. 3.06 program. and with it set up as stock exhaust manifolds w/ mufflers it was showing me making 268hp at 5500 rpm then changing it to small tube header w/ mufflers it was showing me making 315hp at 5500rpm. does that sound crazy or does it make that much of a difference 47hp? i am planning on installing tri-y headers so i figure they would be small tube. __________________ Pittsburgh Steelers/Penguins/Pirates FTMFW!!!!! Last edited by Vinyl66; February 28th, 2008 at 08:58 PM.

February 28th, 2008, 09:47 PM	#2
Vinyl66 Anatidaephobic 1966 Vinyl Mustang 2012 Hyundai Elantra GLS Join Date: Sep 2007 Posts: 2,353 iTrader: 0 reviews	another question about the est. is with the combustion chamber at 54.58cc it has the compression ratio at 12.50 sound right? __________________ Pittsburgh Steelers/Penguins/Pirates FTMFW!!!!!

February 29th, 2008, 09:47 AM	#3
460brevill Hardcore Enthusiast Join Date: Apr 2007 Location: Farmville VA Posts: 1,327 iTrader: 0 reviews	i dont think headers will give that much extra hp,and that comp. cant be right? __________________ i sixing 200 six with 300 hp.

February 29th, 2008, 10:59 AM	#5
460brevill Hardcore Enthusiast Join Date: Apr 2007 Location: Farmville VA Posts: 1,327 iTrader: 0 reviews	what piston are you running? __________________ i sixing 200 six with 300 hp.

February 29th, 2008, 11:29 AM	#7
460brevill Hardcore Enthusiast Join Date: Apr 2007 Location: Farmville VA Posts: 1,327 iTrader: 0 reviews	on performance counts dyno,try y over stock gave us 26 extra hp,with short stroke and stock pistons i we are comeing up with 1105 at .030 over. __________________ i sixing 200 six with 300 hp.

February 29th, 2008, 01:03 PM	#9
460brevill Hardcore Enthusiast Join Date: Apr 2007 Location: Farmville VA Posts: 1,327 iTrader: 0 reviews	real dyno __________________ i sixing 200 six with 300 hp.

February 29th, 2008, 01:52 PM	#10
Vinyl66 Anatidaephobic 1966 Vinyl Mustang 2012 Hyundai Elantra GLS Join Date: Sep 2007 Posts: 2,353 iTrader: 0 reviews	hmmm... i wonder what is a better est. then. 54cc (which i have) @ 12.5comp = 315hp or 64cc @ 10.5comp= 297hp __________________ Pittsburgh Steelers/Penguins/Pirates FTMFW!!!!!

February 29th, 2008, 07:07 PM	#11
Vinyl66 Anatidaephobic 1966 Vinyl Mustang 2012 Hyundai Elantra GLS Join Date: Sep 2007 Posts: 2,353 iTrader: 0 reviews	alright i keep playing with the program and found i have my valves at the wrong diameter and i calculated the comp wrong. now with it set at 10.85 comp i am making 267hp @ 5500rpm on manifolds. with small tube headers i am making 316hp @ 5500rpm. still jumping like crazy but if that happens for real i won't mind but, i think ive got it pretty much 100% dialed in except exact cam specs but i feel im close on those numbers __________________ Pittsburgh Steelers/Penguins/Pirates FTMFW!!!!!

March 7th, 2008, 09:46 PM	#12
MustangOne Lost in the 60's 1968 GT 500 Super Snake 12.6 @ 114.3 Join Date: Mar 2008 Location: Sapulpa Oklahoma Posts: 1,947 iTrader: 0 reviews	See if this helps any. We use hedman headders. Fit alot better than tri y's and are only 149.00 and the Coated ones are 279.00 in summit. and fit and look great. stock set up is 9.5:1 with the 54 cc heads. at 12.5 93 octane gas almost works __________________ MustangOne's Car's How to post Photos in Your Thread. Vote for your Favorite Ride of the month, Every Month Modded Mustangs Facebook

March 8th, 2008, 09:09 AM	#13
460brevill Hardcore Enthusiast Join Date: Apr 2007 Location: Farmville VA Posts: 1,327 iTrader: 0 reviews	most people on here dont like headmans.i have been useing them for 30 years and love them.i do a lot of the shortys on the mid 80s and up.easy fit and good power adder. __________________ i sixing 200 six with 300 hp.

March 8th, 2008, 10:56 AM	#14
Vinyl66 Anatidaephobic 1966 Vinyl Mustang 2012 Hyundai Elantra GLS Join Date: Sep 2007 Posts: 2,353 iTrader: 0 reviews	whats the reasoning that people don't like them? and is it better to go with collector diameter for you exhaust match? IE those headers have a 3 inch collector so would 3 inch exhaust be the optimal fit? __________________ Pittsburgh Steelers/Penguins/Pirates FTMFW!!!!! Last edited by Vinyl66; March 8th, 2008 at 11:10 AM.

March 8th, 2008, 11:12 AM	#15
Vinyl66 Anatidaephobic 1966 Vinyl Mustang 2012 Hyundai Elantra GLS Join Date: Sep 2007 Posts: 2,353 iTrader: 0 reviews	because i wanted to put these on. Flowmaster __________________ Pittsburgh Steelers/Penguins/Pirates FTMFW!!!!!

March 8th, 2008, 11:17 AM	#16
MustangOne Lost in the 60's 1968 GT 500 Super Snake 12.6 @ 114.3 Join Date: Mar 2008 Location: Sapulpa Oklahoma Posts: 1,947 iTrader: 0 reviews	I Love Hedman headders. They fit with out dinging and have greater flow than tri y's. The last 2 sets of tri y's we had to ding both sides at the back of the shock towers __________________ MustangOne's Car's How to post Photos in Your Thread. Vote for your Favorite Ride of the month, Every Month Modded Mustangs Facebook

March 8th, 2008, 01:23 PM	#18
MustangOne Lost in the 60's 1968 GT 500 Super Snake 12.6 @ 114.3 Join Date: Mar 2008 Location: Sapulpa Oklahoma Posts: 1,947 iTrader: 0 reviews	I have put 2 sets on 1965 and 1 set on a 1966. Fit great Look good. Love the price. My Neon Green 1965 have them and my 1965 GT Conv have them. And Intalled them on a Customers 1966 coupe with 4 Speed. Had zero problems. __________________ MustangOne's Car's How to post Photos in Your Thread. Vote for your Favorite Ride of the month, Every Month Modded Mustangs Facebook

March 8th, 2008, 11:11 PM	#19
460brevill Hardcore Enthusiast Join Date: Apr 2007 Location: Farmville VA Posts: 1,327 iTrader: 0 reviews	put the headmans on 65/66 with 2 1/2 inch to flowmasters and out the back.you cant go wrong. __________________ i sixing 200 six with 300 hp.

March 9th, 2008, 12:39 PM	#20
jspagna1 Regular Join Date: Nov 2007 Location: Connecticut Posts: 58 iTrader: 0 reviews	I've never had issues with the Tri-Y's. This is mu 2nd Mustang with them. I did get ceramic coated one this time. The rest of the exhaust is 2.5" all the way out the back with H-Pipe & 40 Series Flows. As for the Try-Y's having smaller tubes, it's called more torque, which IMO win's races. __________________ 1966 Mustang Coupe Ford Racing 5.0 HO Roller Motor/B303 Cam/1.7 RR TFS TW 205 Heads/Ceramic Coated Tri-Y Headers Edelbrock Performer RPM/Holley 650 DP 8 qrt Milodon oil pan/Griffin aluminum radiator Mallory Distributor/MSD/Holley Electric Fuel Pump 2.5" Exhaust with H pipe/2 chamber Flowmasters Auburn 3:55's rear/Aluminum drive shaft + loop SSBC disc brakes/C-4 wTCI 2800 15x6/15x7 Torque Thrust D's BFG Drag Radials Fiberglass Shelby hood/frt valance/trunk/bumpers

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