Dyno numbers good (at least for me)

Rev · 02-13-2005, 07:00 PM

I went to a new shop here in Houston for DynoJet pulls. It was a high end shop that builds road racing Porsches. The shop is named Protechnic and I do recommend them. 5 pulls for $85.

My car dynoed at 280 @5700/293@4000. That's the best it's ever done. I had ditched my mechanical fan completely now having both a pusher and puller electric fans. I also got rid of the resonator exhaust tips that I was running. I suspected that they added some back pressure and that was correct. I now have only 1.5 psi back pressure when it used to be 3 psi.

Both these things apparently added 20-30 hp to the rear wheels. These are uncorrected numbers and they are on a different dyno from past dyno runs. They did dyno a new Dodge truck with a hemi in it soon after me. He dynoed 270 with the auto tranny. He has a factory rating of 345 hp. Also has a heavier tranny and differential and so probably less drivetrain efficiency.

Anyway, from that info, I figure I probably have around the same 345 hp that he has since I dynoed a little highrer. Just thought I would share.

Rev

rwhite65 · 02-13-2005, 10:14 PM

Congrats! Now you got me wondering though. When you say the resonators, are you talking about the exhaust tips that stick thru the back roll pan, the exhaust extensions?

I tried to include a picture here. If so, I still have these on my car.
Ryan

Rev · 02-14-2005, 08:49 PM

I was running PaceSetter tips on my 2 1/2" pipes. These were 3" tips about 18" long. The problem was that to have room for the sound deadening material, the inside diameter actually restricted down to about 1 3/4" or 1 5/8". That restriction actually raised my back pressure to 3 psi measured right behind the headers. I just changed to a 3" Hooker tip without any sound deadening going from my 2 1/2" tail pipe to the 3" tip. That lowered the back pressure to 1.5 psi.

Rev

EZRIDN · 02-14-2005, 09:18 PM

Cool....nice numbers throught the auto.

rwhite65 · 02-22-2005, 01:17 AM

Hey Rev,
I can not quit thinking the exhaust tips I have are slightly hurting me as well. From your pics, you have the exhaust thru the roll pan as I do. Will you post some pics of the new exhaust at the rear...and let me know where you got the new tips??
Ryan

Rev · 02-22-2005, 08:43 PM

The new tips look just like the old tips from the outside. They just do not have any sound deadening in them (thereby not reducing the inside diameter). They also were shorter requireing an extension for the tail pipe to exhaust tip (PINTA). They are Hooker slash end tips 3" / 2 1/2" that I got from Jegs for about $30-40.

The only way to know if you get a reduction in back pressure is to measure it before and after. That's what I did, and I believe the reduction helped me some.

Rev

rwhite65 · 02-22-2005, 09:21 PM

Thanks Rev, that is exactly what I was lookin for.
Ryan

02-13-2005, 07:00 PM	#1
Rev Registered Member Join Date: Nov 1998 Location: Houston, Tx. Posts: 3,887	Dyno numbers good (at least for me) I went to a new shop here in Houston for DynoJet pulls. It was a high end shop that builds road racing Porsches. The shop is named Protechnic and I do recommend them. 5 pulls for $85. My car dynoed at 280 @5700/293@4000. That's the best it's ever done. I had ditched my mechanical fan completely now having both a pusher and puller electric fans. I also got rid of the resonator exhaust tips that I was running. I suspected that they added some back pressure and that was correct. I now have only 1.5 psi back pressure when it used to be 3 psi. Both these things apparently added 20-30 hp to the rear wheels. These are uncorrected numbers and they are on a different dyno from past dyno runs. They did dyno a new Dodge truck with a hemi in it soon after me. He dynoed 270 with the auto tranny. He has a factory rating of 345 hp. Also has a heavier tranny and differential and so probably less drivetrain efficiency. Anyway, from that info, I figure I probably have around the same 345 hp that he has since I dynoed a little highrer. Just thought I would share. Rev __________________ '66 Coupe, 306, 350-375 HP, C-4, 13.07 e.t., 104.8 mph, 1/4 mi. O.B.C. #2 '66 coupe

02-14-2005, 08:49 PM	#3
Rev Registered Member Join Date: Nov 1998 Location: Houston, Tx. Posts: 3,887	Re: Dyno numbers good (at least for me) I was running PaceSetter tips on my 2 1/2" pipes. These were 3" tips about 18" long. The problem was that to have room for the sound deadening material, the inside diameter actually restricted down to about 1 3/4" or 1 5/8". That restriction actually raised my back pressure to 3 psi measured right behind the headers. I just changed to a 3" Hooker tip without any sound deadening going from my 2 1/2" tail pipe to the 3" tip. That lowered the back pressure to 1.5 psi. Rev __________________ '66 Coupe, 306, 350-375 HP, C-4, 13.07 e.t., 104.8 mph, 1/4 mi. O.B.C. #2 '66 coupe

02-14-2005, 09:18 PM	#4
EZRIDN Registered Member Join Date: Jan 1999 Location: U.S.A. Posts: 504	Re: Dyno numbers good (at least for me) Cool....nice numbers throught the auto. __________________ '86 GT..5 spd....14.0 @ 98 SOLD '87 GT..5 spd...Stock...14.4 @ 97 SOLD '90 GT Conv. A4 Cream Puff...14.6 @ 94 SOLD '99 Z28..A4..Stock stall, no tuning, all motor, full weight 11.92 @ 117.95 SOLD '03 Centennal Edition GT 5 spd. 1 of 620 5 spd coupes made. http://bradbarnett.net/mustangs/timeline/99-04/03/100th.htm Stock..... 2.02 8.9 13.89 @ 99.03 http://bradbarnett.net/mustangs/timeline/99-04/03/100th.htm

02-22-2005, 01:17 AM	#5
rwhite65 Ride Hard Join Date: Oct 2000 Location: Wyoming IL Posts: 1,094	Re: Dyno numbers good (at least for me) Hey Rev, I can not quit thinking the exhaust tips I have are slightly hurting me as well. From your pics, you have the exhaust thru the roll pan as I do. Will you post some pics of the new exhaust at the rear...and let me know where you got the new tips?? Ryan __________________ 65 Fastback 91 roller 306, H/C/I AOD-Bauman, PI Stallion, 4.10's and traction loc 04 Grand Cherokee Freedom Edition 79 Ford F-250 4x4 - Restored

02-22-2005, 08:43 PM	#6
Rev Registered Member Join Date: Nov 1998 Location: Houston, Tx. Posts: 3,887	Re: Dyno numbers good (at least for me) The new tips look just like the old tips from the outside. They just do not have any sound deadening in them (thereby not reducing the inside diameter). They also were shorter requireing an extension for the tail pipe to exhaust tip (PINTA). They are Hooker slash end tips 3" / 2 1/2" that I got from Jegs for about $30-40. The only way to know if you get a reduction in back pressure is to measure it before and after. That's what I did, and I believe the reduction helped me some. Rev __________________ '66 Coupe, 306, 350-375 HP, C-4, 13.07 e.t., 104.8 mph, 1/4 mi. O.B.C. #2 '66 coupe

02-22-2005, 09:21 PM	#7
rwhite65 Ride Hard Join Date: Oct 2000 Location: Wyoming IL Posts: 1,094	Re: Dyno numbers good (at least for me) Thanks Rev, that is exactly what I was lookin for. Ryan __________________ 65 Fastback 91 roller 306, H/C/I AOD-Bauman, PI Stallion, 4.10's and traction loc 04 Grand Cherokee Freedom Edition 79 Ford F-250 4x4 - Restored

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