: OT: Hemi makes 368 rwhp on dyno, stock



Florian
07-01-05, 12:18 PM
Fellas (and Dannystang),

College roommate of mine now working for a company in MI that is offering a s/c package to Hemi owners has dynoed over 20 hemi engines and the average rwhp is 368. These motors are not to be trifled with...however, he reports that the top ring land is about 1/3 the size of the LSx motors and cant take much boost as a result (good news for us V guys). Food for thought.

F

lasstss
07-01-05, 12:20 PM
Fellas (and Dannystang),

College roommate of mine now working for a company in MI that is offering a s/c package to Hemi owners has dynoed over 20 hemi engines and the average rwhp is 368. These motors are not to be trifled with...however, he reports that the top ring land is about 1/3 the size of the LSx motors and cant take much boost as a result (good news for us V guys). Food for thought.

F

Unfortunately that is 50-60 horses more than most of us stock..

RobertCTS
07-01-05, 12:42 PM
That must be the small block Hemi?(345HP) The 6.1 stock Hemi put out 425HP and with a SC who knows.

This my wife's Hemi Magnum.

thebigjimsho
07-01-05, 01:03 PM
368 would be 30 more than my V. That's pretty close to where it's suppose to be. Bring it on!

thebigjimsho
07-01-05, 01:08 PM
That must be the small block Hemi?(345HP) The 6.1 stock Hemi put out 425HP and with a SC who knows.

This my wife's Hemi Magnum.368(r)ear (w)heel horsepower is slightly above the 425hp the engine is rated by Dodge to make.

RobertCTS
07-01-05, 01:38 PM
What's the rule of hand on HP loss to the rear wheels? 25%? That would put a 425 down to 319HP. A 50HP gain w/SC to get to 368HP?

thebigjimsho
07-01-05, 02:01 PM
I think a pretty common calculation is about a 20% loss for a RWD automatic. That would have the SRT-8 around 440hp instead of 425hp.

If the V had a 15% drivetrain loss, my 338hp would equal 388hp. If it's a 17% loss, 338hp would equal 396hp.

But, ultimately, it's what you get down. So the average SRT-8 gets 30 more hp to the ground and carries an extra 350lbs. So take it for what it's worth.

GNSCOTT
07-01-05, 02:21 PM
I think a pretty common calculation is about a 20% loss for a RWD automatic. That would have the SRT-8 around 440hp instead of 425hp.

If the V had a 15% drivetrain loss, my 338hp would equal 388hp. If it's a 17% loss, 338hp would equal 396hp.

But, ultimately, it's what you get down. So the average SRT-8 gets 30 more hp to the ground and carries an extra 350lbs. So take it for what it's worth.

That 20% for an auto is just a guideline. It all depends on the convertor and gearing in the tranny itself, and The SRT-8 tranny from what I hear is almost as tight as a manual. No Dyno is created equal. If your car is capable of running a low 13, you need 400hp to do it in a 4000+lb car and driver. I know my car has a very low 13 and I know that SRT-8's will run low 13's all day long because of the auto (less driver error).

2005V
07-01-05, 05:17 PM
Mine was 17% drive train loss on the money (using GM's 400HP figure) the first time around on the dyno to set a baseline.

Dooman
07-01-05, 05:39 PM
I thought he meant the 340hp version too? I can't imagine any one shop right now that has had 20 SRT cars in-house yet! Could a s/c bring the 5.7 Hemi up that far?

RobertCTS
07-01-05, 05:54 PM
I posted earlier that my wife has the 5.7 Hemi. Her dealer said the 6.1 and AWD were next to impossible to get.

Florian
07-01-05, 06:20 PM
theve had well over 20 SRT Hemis in house. They are a development house and they do all the testing on the Hemis.

F

RobertCTS
07-01-05, 06:32 PM
theve had well over 20 SRT Hemis in house. They are a development house and they do all the testing on the Hemis.

F
That's probably why the dealers are still in line.

MikeF
07-02-05, 07:09 PM
I just watched an old Spielberg film, "The Duel". It reminded my why I don't buy Chrysler.

Dooman
07-05-05, 10:31 AM
Thanks for the info then, it is a nice vehicle!

dannystang
07-06-05, 01:27 PM
Fellas (and Dannystang),

College roommate of mine now working for a company in MI that is offering a s/c package to Hemi owners has dynoed over 20 hemi engines and the average rwhp is 368. These motors are not to be trifled with...however, he reports that the top ring land is about 1/3 the size of the LSx motors and cant take much boost as a result (good news for us V guys). Food for thought.



F

LOL I was on vacation just checking old posts...I c were at it again ;)

Florian
07-06-05, 02:19 PM
Dannystang,

Just a bit of jocularity in the old forum for giggles. :) No offense meant.

Florian

Playdrv4me
07-06-05, 02:51 PM
Im still lost.

The title of this thread is 368rwhp STOCK. Are we talking about the 345HP 5.7L version or the 425HP 6.1L?

And what is the talk about the s/c? If it has an S/C then its not stock is it?

wildwhl
07-06-05, 03:00 PM
Playdrv4me -

I believe Florian's comments are stock numbers...with S/C they're dynoing much better than that :)

Florian
07-06-05, 03:01 PM
the 6.1L

F

Florian
07-06-05, 03:02 PM
WW is correct as well

F

Playdrv4me
07-06-05, 03:04 PM
Nice!

Mowgli
07-06-05, 09:08 PM
Hmm. The Ford's SC4.6 rated at "390hp" with a T56 and IRS put down mid 360s rear wheel hp on average. The LS6 with ten more hp rated at "400hp" and with the exact same T56 tranny and also an IRS puts down 330 rear wheel hp. Or the GTO with the same "400hp" rating but a different engine, albeit an identical tranny and again an IRS and we see 340 rear wheel hp.

Now comes Chrysler with rear wheel hp in the 360s, an IRS but with an auto, and calling it "425hp".

I love the always magical game of factory power rating.

Ah the ever changing "driveline loss", god bless ya.

Vrocks
07-06-05, 10:27 PM
We all know dyno numbers don't tell the whole story. Who knows how accurate that dyno was, and the gearing, power band / mechanical advantage mean a lot.