Dyno'd my 4.0 today

[alex22]

A local shop had a dyno day and I went to check the place out and a few of my friends were going to be testing and tweaking their cars. At the end of the day they had a few slots open so I figured why not. 30 bucks for 3 pulls.

The XJ: Stock engine with 177K, K&N air filter that hasn't been cleaned in over a year, stock exhaust with cracked header and a vacuum leak, 5 speed, ford 8.8 with 3.73 gears on 31's.
This is a 3rd gear pull. The first two pulls were within a few hp and a few ft-lbs of this one.

Peak HP: 133.1 @ 4650
Peak TQ: about 164 @ 2650
There's a video of this somewhere.

EDIT: The AFR meter was not hooked up.

At least now I'll have a baseline to compare my new engine to, whenever I get around to building it. I beat a Sunfire with a fart can by 20HP

 

[Talyn]

Not bad numbers for mostly stock and that mileage.

 

[RadioShackSpecial]

I love that TQ curve, no wonder these things will pull a train.

 

[Boostwerks.com]

Not bad at all Alex. What dyno is that?

 

[Dr. Dyno]

Those numbers are not bad considering this is a very high mileage engine with a dirty air filter, vacuum leak, and a leaking header. I like the torque plateau from 2500-4000rpm.

 

[foxwar71]

This is a 3rd gear pull.

Whats up with that? all the dyno's ive seen are meant to be run with the cars tranny at 1:1, 4th gear in most manual trannys. i jsut have a hard time seeing that high of a HP # considering the engine. ive seen jeeps with very similar setups (150k+, no mods, 5spd, 3.55's, 31's) put down HP consistantly around the 90-100 mark at the wheels.



Im not calling you out or anything, ive just seen how a lower gear or an auto can put out a rating higher then what it seems it should be cause of the added gear reduction/torque multiplacation.

 

[alex22]

Bryson, It is a DynoMite dyno by Land and Sea. I didn't ask the shop owner but I was told that it is an eddie current dyno.

Foxwar71, The pull was done in 3rd gear because without disconnecting the speed sensor the computer would have prevented a full pull in 4th gear. 5400 RPM works out to 133MPH in 4th gear but only 92 in 3rd gear.

I should also mention that the jeep got an italian tune up prior to the dyno run.

 

[Killsaurus]

Accident

 

[Talyn]

i jsut have a hard time seeing that high of a HP # considering the engine.

I don't. Considering the 190hp stock is taken at the fly wheel there isn't anything out of line with his numbers.

When I ran my 2000 back in 2006 on the dyno it had Rusty's K&N, 62mm throttle body, Doug Thorley header, Gibson 2.5" exhaust, and 80,000 miles. It put down 149 hp and 183 torque. 3rd Gear on the AW4.

 

[Darky]

Whats up with that? all the dyno's ive seen are meant to be run with the cars tranny at 1:1, 4th gear in most manual trannys. i jsut have a hard time seeing that high of a HP # considering the engine. ive seen jeeps with very similar setups (150k+, no mods, 5spd, 3.55's, 31's) put down HP consistantly around the 90-100 mark at the wheels.



Im not calling you out or anything, ive just seen how a lower gear or an auto can put out a rating higher then what it seems it should be cause of the added gear reduction/torque multiplacation.

90-100 sounds like something else is off...that's a 50% loss in the drivetrain and usually people cite an approximate 30% loss. 130hp sounds about right for a 30% loss.

 

[FlexdXJ]

At least it wasn't 60 hp like the Jeep they built on trucks! Your engine is still in good shape apparently!

 

[foxwar71]

I don't. Considering the 190hp stock is taken at the fly wheel there isn't anything out of line with his numbers.

90-100 sounds like something else is off...that's a 50% loss in the drivetrain and usually people cite an approximate 30% loss. 130hp sounds about right for a 30% loss.

:doh::doh:


silly me, now i know i have my head up my ass. it totally slipped my mind that the jeeps that i saw pull down those 90-100 #'s was when i was out in wyoming at the awesome elevation of 7200 ft above sea level :gee:

 

[Talyn]

the awesome elevation of 7200 ft above sea level :gee:

LOL that could have been a contributing factor.

 

[wolfpackjeeper]

5% per 1k' or so isn't it?

 

[88 Wagonman]

5% per 1k' or so isn't it?

I have always heard 3.5%\1000 ft.

 

[Talyn]

I thought it was 4%

 

[alex22]

Well whatever the correction factor is these numbers were corrected to SAE numbers Maybe the other numbers were not corrected.

 

[child9]

My auto 96 with a K&N that hasn't been cleaned, magnaflow cat and dynomax muffler had my Jeep ring in at just over 130HP and 164 torque in Austin. Hopefully the drivetrain holds together during the dyno pulls after the 2JZ swap. What a difference there should be.

 

[Boostwerks.com]

An SAE correction factor depends on other factors than just altitiude. Realative humidity and temperature are included as well due to their effects on air density.

Different mfg dyno's will output different numbers as well (hence why I had asked Alex).

 

[CherBear]

An SAE correction factor depends on other factors than just altitiude. Realative humidity and temperature are included as well due to their effects on air density.

Different mfg dyno's will output different numbers as well (hence why I had asked Alex).

X2, always heard if you wanted an accurate comparison, use the same dyno.