Expected RWHP on dyno. Guesses anyone?

[Nuclear]

Hello all. I'm very much a rookie when it comes to modern fuel-injected cars, so I'm learning as I go. I will be performing a chassis dyno soon, and I was just wondering if anyone has an "educated guess" on what my combination might produce. Yes, I fully understand that comparing different dyno machines is like comparing women- all are different. I also understand that weather is big factor. I'm just looking for some input from guys who have similar cars, and have factual data (i.e. dyno numbers).

2006 GT/4.6 3V, 5-speed, 3.55. SCT/Bama 93 "race" tune. C+L racer cold air, stock exhaust except for Flowmaster 40-series mufflers, and Brenspeed Detroit Rocker NA cams.

Any guesses on RWHP?

I ran the car down the 1/4 mile yesterday and was disappointed at the 14.30s and 14.40s it ran (@99MPH). Granted, traction was crap at 2.2 seconds, but I really expected a higher MPH. The weather was low 80s and humid. Elevation 650'. Should I expect more?

I appreciate any and all input. Thanks....

-Nick

 

[s8v4o]

Based off your mods I would say guess 310-315 RWHP. Based off your MPH in the 1/4 I would guess 270 RWHP. My car bone stock trapped 102. I don't think that elevation would make a huge difference.

 

[lee12609]

longtubes and an aftermarket crossover will help alot with the cams. without exhaust the cams arent helping as much as they could.

i'd say 280-290whp

 

[lilcrate]

I think your MPH should definitely be higher. That is good elevation. The weather wasn't perfect, but nothing to set it that low.

My '10 with just catback trapped 102 in a few different temperature settings.

 

[BruceH]

Hello all. I'm very much a rookie when it comes to modern fuel-injected cars, so I'm learning as I go. I will be performing a chassis dyno soon, and I was just wondering if anyone has an "educated guess" on what my combination might produce. Yes, I fully understand that comparing different dyno machines is like comparing women- all are different. I also understand that weather is big factor. I'm just looking for some input from guys who have similar cars, and have factual data (i.e. dyno numbers).

2006 GT/4.6 3V, 5-speed, 3.55. SCT/Bama 93 "race" tune. C+L racer cold air, stock exhaust except for Flowmaster 40-series mufflers, and Brenspeed Detroit Rocker NA cams.

Any guesses on RWHP?

I ran the car down the 1/4 mile yesterday and was disappointed at the 14.30s and 14.40s it ran (@99MPH). Granted, traction was crap at 2.2 seconds, but I really expected a higher MPH. The weather was low 80s and humid. Elevation 650'. Should I expect more?

I appreciate any and all input. Thanks....

-Nick

FWIW I've seen a 4.6 3v with off road pipe, Hot Rods, and cai make 300rwhp with a bama tune. It was super safe. IIRC max spark was 27 degrees and a/f was a tad over 12.0. There was an easy 30hp left on the table. It did drive nice though.

Have you thought about a different tune? There are some really good tuners who will do email tunes the right way, with datalogs. Lito on this board comes to mind.

I'm going to guess that your car will make 279rwhp with an sae correction factor on a dynojet.

 

[Nuclear]

For what its worth: I performed a warm compression test on the engine. All cylinders were between 140-150 PSI (throttle open). I'm trying to schedule a chassis dyno session for next week.
I have not ruled out a lame tune yet. After I see some dyno numbers, I may be trying a different tune.
What does a completely stock 3V put down to the tires? 250 HP? Anyone have numbers on that?

Nick

 

[s8v4o]

For what its worth: I performed a warm compression test on the engine. All cylinders were between 140-150 PSI (throttle open). I'm trying to schedule a chassis dyno session for next week.
I have not ruled out a lame tune yet. After I see some dyno numbers, I may be trying a different tune.
What does a completely stock 3V put down to the tires? 250 HP? Anyone have numbers on that?

Nick

When you did your compression test did you disconnect your injectors? If you didn't then the fuel could have skewed your numbers a little bit. I've never done a compression test on the 4.6 but my 2.3L turbo with only 8.0:1 compression had about 155PSI. I'm not sure what the typical compression is on these motors. Stock motors usually put down about 250-260 RWHP.

 

[Steedman07]

driver mod...ftw..Stick or auto?

 

[Nuclear]

The car is a manual, and I performed the compression check with the fuel pump relay removed

 

[RED09GT]

With the longer duration cams and them being fully advanced with no computer control, I would think that your cranking compression is about right. With the cams advanced, the exhaust will open early and add on the extra duration of the Detroit rockers and that will make for some relatively low cranking numbers.
As long as they are consistent, it should be okay.

Sent from my HTC Desire HD A9191 using Tapatalk 2

 

[Renesis07]

I put down 313whp on a dynojet.

My car has LT headers, catless H pipe, JLT intake, Delete plates, UD Pulleys, and a Bama tune.

My guess for yours is right around 300whp, longtubes will help you a lot.

 

[BruceH]

For what its worth: I performed a warm compression test on the engine. All cylinders were between 140-150 PSI (throttle open). I'm trying to schedule a chassis dyno session for next week.
I have not ruled out a lame tune yet. After I see some dyno numbers, I may be trying a different tune.
What does a completely stock 3V put down to the tires? 250 HP? Anyone have numbers on that?

Nick

3v manual is good for 270 or so rwhp. Depends on the dyno.

 

[Renesis07]

3v manual is good for 270 or so rwhp. Depends on the dyno.

Yea that's about right. My buddy just dyno'd his stock 09 GT (only has axlebacks and a K&N intake - no tune), and it put down 264whp on a mustang dyno.

 

[QWIKFIX]

For comparisons...I have manual with 3.31s, ran mine late sept on a hot (mid 80s) afternoon, track at 475ft, left off idle (TC off) with 60fts from 2.35 to 2.44 on stock tires, trapped between 104 and 109mph (best time 13.8ish). I have bolt ons and a tune and dyno'd on a mustang dyno (actually same dyno at 2 different locations) 309/323 stock exhaust + hit my speed limiter/rev limiter, last dyno 319/325 with FRPP GTA mufflers and speed limiter off/rev limiter set higher.

 

[W3bb3r04]

FWIW I've seen a 4.6 3v with off road pipe, Hot Rods, and cai make 300rwhp with a bama tune. It was super safe. IIRC max spark was 27 degrees and a/f was a tad over 12.0. There was an easy 30hp left on the table. It did drive nice though.

Have you thought about a different tune? There are some really good tuners who will do email tunes the right way, with datalogs. Lito on this board comes to mind.

I'm going to guess that your car will make 279rwhp with an sae correction factor on a dynojet.

Mine made 331/331 with Hotrods, Bassani X, Axle backs, CAI and bama tune on Pro Dyno's Dynojet.

 

[Renesis07]

Mine made 331/331 with Hotrods, Bassani X, Axle backs, CAI and bama tune on Pro Dyno's Dynojet.

Those numbers are solid for not having longtubes...

 

[muztangman93]

Dude I need your roush wheels

 

[BruceH]

Mine made 331/331 with Hotrods, Bassani X, Axle backs, CAI and bama tune on Pro Dyno's Dynojet.

Good for you! The guy I saw on the dyno eventually traded for a 2013. He was pretty dissapointed. We were all making fun of the a/f and spark advance. What was your a/f and spark advance? I have a feeling that they toned everything down after 5.0 motors started popping. Keep in mind that different dynos give different results.

 

[QWIKFIX]

Good for you! The guy I saw on the dyno eventually traded for a 2013. He was pretty dissapointed. We were all making fun of the a/f and spark advance....

Hmm that wasnt a certain..."HEMI" something or other..

 

[BruceH]

Hmm that wasnt a certain..."HEMI" something or other..

Annonymity is a fundamental part of our... Sorry, wrong group.