Engine Dyno:How do you run the Hemi to have any REAL world numbers? [Archive] - Cherokee SRT8 Forum

: Engine Dyno:How do you run the Hemi to have any REAL world numbers?


BuilderBill
06-14-2007, 03:56 PM
Hey guys,
My 426 stroker engine was run on the dyno at Indy Cylinder Heads. They used a mechanical linkage and FAST electronics / fuel management. That ain't the way I will be running the Hemi now is it???

Anyone else have their mighty Hemi engine dyno tested any other way?

ASM is about done with the technology to dyno test our Hemi's more realistically:
They have my PCM (thats where one of many went :D).
They have a complete wiring harness fabricated.
The throttle is being activated by our actual jeep accelerator pedal assy.Don't you thing that is is a more realistic (yes, a ton of work) way of dyno testing our Hemi's....use real world fuel & spark management rather that a FAST system with a mechanical throttle.

My 426 should be running on the engine dyno there soon...any bets on whether it makes more or less hp than at Indy????
Bill

GotStroke?
06-14-2007, 04:11 PM
Yes the numbers at Indy are going to be higher. The only way to truly know will be to run the complete induction/exhaust setup you'll use on the road paired with the engine management system/tune you'll also use in the real world.
It would be neat if possible as we could then see a true figure for actual driveline loss (I believe 25% through the trans, transfer case, two diffs, and heavy 20" wheels with runflats), but I don't know if it's possible.
ps, good info for you in my last post in the SWorks vs. Kooks thread;)

BuilderBill
06-14-2007, 04:38 PM
Yes the numbers at Indy are going to be higher. The only way to truly know will be to run the complete induction/exhaust setup you'll use on the road paired with the engine management system/tune you'll also use in the real world.
It would be neat if possible as we could then see a true figure for actual driveline loss (I believe 25% through the trans, transfer case, two diffs, and heavy 20" wheels with runflats), but I don't know if it's possible.
ps, good info for you in my last post in the SWorks vs. Kooks thread;)
Stroker...got your Sworks post. I will most likely go with them do to the no cel's and the way they respond to our needs.

I am trying to get the engine dyno testing as close as possible to real life. I will see after the last engine mods on the engine dyno, the engine will be installed and the jeep driven outside to the ASM chassis dyno. That should give us a very realistic number between the engine dyne and chassis dyno.
Bill

GotStroke?
06-14-2007, 04:42 PM
Stroker...got your Sworks post. I will most likely go with them do to the no cel's and the way they respond to our needs.

I am trying to get the engine dyno testing as close as possible to real life. I will see after the last engine mods on the engine dyno, the engine will be installed and the jeep driven outside to the ASM chassis dyno. That should give us a very realistic number between the engine dyne and chassis dyno.
Bill

That's going to be some interesting info, we've been guessing at DT losses for quite a while. Thanks again for your contributions to the "cause".

Blown7
06-14-2007, 05:30 PM
Well at this point your comparing apples to oranges IMHO.
If the engine ran at Indy normally aspirated and now at ASM it's running with a blower then the numbers will be all over.

What you should do now is run the engine without the blower with the OEM PCM take the numbers, compare, then hook the blower up.

Then chassis dyno, you'll have all the info you could ever want.

Jeff

BuilderBill
06-14-2007, 09:08 PM
Well at this point your comparing apples to oranges IMHO.
If the engine ran at Indy normally aspirated and now at ASM it's running with a blower then the numbers will be all over.

What you should do now is run the engine without the blower with the OEM PCM take the numbers, compare, then hook the blower up.

Then chassis dyno, you'll have all the info you could ever want.

Jeff
Jeff,
The engine has NOT been touched as far as any upgrades like a supercharger yet. This is why I want to run it vs. the dyno at Indy. Sorry for the confusion! Then the supercharger, cam etc. etc.
I need to give you a buzz regarding your gage.
Bill

Blown7
06-15-2007, 05:42 AM
Jeff,
The engine has NOT been touched as far as any upgrades like a supercharger yet. This is why I want to run it vs. the dyno at Indy. Sorry for the confusion! Then the supercharger, cam etc. etc.
I need to give you a buzz regarding your gage.
Bill

K gotcha. Then your just going to run the engine at ASM with the OEM PCM tuned by B&G.
Well that will reflect what the FAST vs B&G controllers will provide for power.

Jeff

BuilderBill
06-15-2007, 06:27 AM
K gotcha. Then your just going to run the engine at ASM with the OEM PCM tuned by B&G.
Well that will reflect what the FAST vs B&G controllers will provide for power.

Jeff Actually, the Hemi will be run with the STOCK PCM 1st.
Then, the ASM user PROGRAMMABLE PCM (piggybacked) will be tested. This will be revolutionary and use a reluctor on the back of the balancer and it will be manufactured so you do not have to drop the crank and change reluctors....which obviously makes for a simpler install. The dropping of the crank is NOT a backyard project.:eek:
A work in progress photo of the reluctor wheel to balancer is attached.
Bill

gculver
06-15-2007, 07:03 AM
Bill, Good Luck! I'm most interested in the nuts & bolts(so to speak) of ASM's new tuning package!! GC
PS: did you get my PM about the box?

BuilderBill
06-15-2007, 07:11 AM
Bill, Good Luck! I'm most interested in the nuts & bolts(so to speak) of ASM's new tuning package!! GC
PS: did you get my PM about the box?
GC...I replied pm'ed right back to you. The Volant & ram setup is yours. Glad I can help the cause. It may be 60 days or so.
Bill

gculver
06-15-2007, 07:34 AM
Bill, Please check my reply!! Thanks!!