4.6 build starts today!!!

[Redsnake]

Man that's awesome!! My '01 XJ may need a new motor in a little bit and if this became a 'package' of sorts I'd be glad to know the cost to start saving or heck just order one up...

I wonder if those torque numbers will give the OE drivetrain any issues... :\

 

[XJEEPER]

Well, today was the big day and it came off perfectly! The guys at Lopers said they hadn't seen such a strong motor!

Max rear wheel horsepower = 227hp
Max rear wheel torque = 396 ft/lbs

AFR's were great with just a slight fattening under 50% dyno load and WOT.

I think I'm done now!

Impressive!!

 

[RCP Phx]

You're killing me smalls!!! Why did you have to do that? 225 hp/400 ft-lb at mid 9s CR?!?! I need new underwear. Been waiting to see a 0331 based build with dyno numbers and now we know. I think this will start a few conversations...

Question, Chris and Russ, any chance of a "package"? This build sheet, these injectors, this tune, done! Drooling...

Russ will give you a quote on anything/everything your budget will allow. This whole thread is a "build sheet" and I have not done any "computer tuning" even though I have spoke with Chris thru-out the build!

 

[RCP Phx]

Man that's awesome!! My '01 XJ may need a new motor in a little bit and if this became a 'package' of sorts I'd be glad to know the cost to start saving or heck just order one up...

I wonder if those torque numbers will give the OE drivetrain any issues... :\

I didn't set a budget when I took this on, but with my build (with me doing all the work) it ran about 5k!

The Toyota guys put a lot more HP to the AW4!

 

[Boostwerks.com]

Well, today was the big day and it came off perfectly! The guys at Lopers said they hadn't seen such a strong motor!

Max rear wheel horsepower = 227hp
Max rear wheel torque = 396 ft/lbs

AFR's were great with just a slight fattening under 50% dyno load and WOT.

I think I'm done now!

Holy crap. Do you have the graph? 400ft/lbs for that HP just sounds almost unbelievable (not saying your lying).

:yelclap:

 

[RCP Phx]

I've got the print outs from the "Dynojet" machine they use.

 

[Boostwerks.com]

Willing to post em up?

EDIT: BTW, what gear was it done in?

 

[RCP Phx]

Well that was fun, first my scanner didn't work, then the camera didn't work!

 

[RCP Phx]

Willing to post em up?

EDIT: BTW, what gear was it done in?

It was done on a rolling dyno thru all gears and with different loads!
Lopers is one of the best race shops in Phoenix, the shop has been here since 67 and John Loper has been winning drag races even before that!

 

[Exxon Valdez Jeep]

That's nuts

 

[JohnX]

It was done on a rolling dyno thru all gears and with different loads!
Lopers is one of the best race shops in Phoenix, the shop has been here since 67 and John Loper has been winning drag races even before that!

I've never heard of a dyno pull thru all gears? What gear was the 400lbft achieved in? It makes a HUGE difference in the numbers to be in different gears.

Also...where's the rpms on the chart??

 

[typerr]

My understanding is Dynojet (and other chassis dyno) pulls are done in your 1:1 gear to remove any effect of torque multiplication so the dyno operator will shift up through the gears to get to the proper ratio during the session.

 

[RCP Phx]

^^^This and without load the motor will not produce it's maximum. I only had a engine dyno and flow bench at my shop but can't imagine all the work that would be involved to run the new EFI motors, back in the day of carbs is was a easy set-up!

JohnX - the RPM's/AFR/Speed and other data is on all the test sessions and I have about 30 pages of print-outs!

 

[Boostwerks.com]

I've never heard of a dyno pull thru all gears? What gear was the 400lbft achieved in? It makes a HUGE difference in the numbers to be in different gears.

Also...where's the rpms on the chart??

This.

The standard way to do it is use a gear that is as close to 1:1 as mentioned. This would be to lock the trans in 3rd gear or to simply prevent it from going into 4th.

If the trans was in 2nd gear peaking 400ft/lbs, the motor obviously isn't actually making that kind of torque due to the gear reduction.

 

[Boostwerks.com]

Some more info..

The way dyno's work is simply to read torque over a certain RPM range. Given that we know that horsepower is simply a function of torque and RPM, we can find out what the true torque output of the engine is even though the peak numbers maybe skewed given the gearing.

HP = TORQUE x RPM ÷ 5252

and

TORQUE = HP x 5252 ÷ RPM

Your peak HP number was 227. Not knowing when this peak occured however, I'd have to assume the RPM. Just googling some graphs of 4.6L strokers it looks like peak HP is around 4500-5000RPM.

Plugging in for an assumed 4500rpm peak, I end up with about 265ft/lbs which sounds about right.

 

[RCP Phx]

The numbers work out for me, peak torque was achieved at about 2900-3000 rpm !

 

[JohnX]

The numbers work out for me, peak torque was achieved at about 2900-3000 rpm !

None of the numbers posted make sense. That is precisely why I wanted to see the graph with rpms present. It really sounds like they ran it in second gear or somethjng? Nobody does it that way, and it gives VERY misleading numbers.

What boostwerks posted is spot on regarding relationships between HP and torque.

 

[Boostwerks.com]

The numbers work out for me, peak torque was achieved at about 2900-3000 rpm !

Was that in 3rd gear though is the question? Not trying to hate, just curious is all.

400ft/lbs from an all Iron 4.6L would be sweet, but it just doesn't jive with what I've seen. For example, Dino's 4.6 put down " 202hp @ 4700rpm & 258lbft @ 3400rpm" with a manual trans in 3rd gear. Your not going to magically make another 150ft/lbs more than this with roughly the same HP.

 

[RCP Phx]

In 4th gear.....

My print-outs show every shift and RPM. If you do the math

Torque = HP x 5252 / RPM

Torque = 227 x 5252 / 3000 = 397.4

I've done business with John and a semi-competitor business with him for over 40 yrs. Either way I didn't go to them for HP/Torque numbers. I went to them to see if my AFR's are good with my new injectors. I attribute the extreme numbers(based on my past big valve/port & polish jobs) to Russ's headwork which was incredible based on my own work!

 

[Boostwerks.com]

My print-outs show every shift and RPM. If you do the math

Torque = HP x 5252 / RPM

Torque = 227 x 5252 / 3000 = 397.4

Right, but again that doesn't tell us which gear it was in. I don't doubt at all that it was putting out 400ft/lbs at 3000rpm. However, my honda also makes 500ft/lbs in first gear... point being I'm not willing to say that the motor makes 500ft/lbs of torque.