Jeep Strokers

Trying to start a dyno results thread.
Please do not make comments at all, I am oping to keep this a super streamlined thread that only has a record of yours build with the dyno results and whether its a flywheel dyno or chassis dyno.
Post relevant info for either.
need block/piston/head info and relevant injector size or carb and TB size... all the things you did to make power.
if chassis-include tranny, gear ratio, and tire size.

its okay to post a link but it would most helpful if you just had your data and maybe a pic of the dyno sheet.

lets try to keep this uncluttered and results only-no questions(PM posters for that please)

maybe a sticky.

I know theres a lot of builds that are bench raced but looking to pool a bunch of REAL world data.

buikd thread

viewtopic.php?t=1364

renix 89 cam

After all these weeks I will end up with 9.93SCR, 7.85DCR, and 0.0429 quench straight zero cam.

chassis is 1981 jeep wagonner with 3.31 axle and 10.5x31-15 tires.
trans is a rebuilt 727 auto-notorious for losing ~75hp through the slushbox.
tcase is 208.

153 hp
203 tq
at the wheels

http://1.bp.blogspot.com/-1OTKoj9Ohrg/U ... 0/dyno.jpg


http://3.bp.blogspot.com/-QtJ_qhsXHRE/U ... /dynog.jpg



89 4.0 block
91 7120 head
various work done to both.
4.2 rods
hyper pistons
1981 crank
84 carb intake
91 HO OEM headers
2150 holly carb 1.13 version? forget. with 48? 51? jets
rebuilt OEM 1981 727 3spd auto trans-slipomatic
208 part time transfer case
3.31 gears
31-10.5-15 street tires
curb weight at 4,000#

My build site: https://www.angelfire.com/my/fan/stroker.html

'92 XJ, AX15 5-speed manual tranny, stock 3.07 axle gears, 225/70R15 tires (27.4").

200.4rwhp @ 4700rpm
https://www.angelfire.com/my/fan/Stroker_Dyno_HP.jpg

257.8rwtq @ 3500rpm
https://www.angelfire.com/my/fan/Stroker_Dyno_TQ.jpg

'00 4.0 XJ block bored +0.020"
Jeep 4.2L 3.895" stroke crank
Jeep 4.2L 5.875" rods
Sealed Power 677CP +0.020" bore pistons
4563cc displacement
9.25:1 CR
Stock '92 4.0 camshaft
DIY ported '92 HO 1.91"/1.50" 57cc cylinder head
Mopar/Victor 0.043" head gasket
0.088" quench height
Ford 24lb/hr injectors
Homebrew MAP sensor voltage adjuster
Homebrew CAI
Modified Mustang Cobra 65mm TB
Tapered 65>62mm TB spacer
'01 intake manifold with custom heat shield
Borla header with 2.5" exhaust, no cat
Dual electric fans

Nobody else?

I tested this XJ before and after the engine swap. This is not my build or my Jeep, but I can share the specs that I'm aware of. As you may notice, the lambda is quite lean, we had a fuel delivery issue, the owner is going to replace the fuel pump and bring it back for final dyno tuning, I don't expect it to pick up much power so I'm posting what I've got. If we see any significant improvements I will update the post.

Dyno: Mainline Pro-Hub , ramp rate aprox. 500 rpm/sec.

Engine:
Forged pistons with mirrored combustion chamber pocket(Russ)
Edelbrock cylinder head, ported(Russ)
Comp cam 68-239-4 ? (nitrided, cam timing retarded to lower dcr)
Static compression close to 10:1
Stock intake manifold, ported
BBK throttle body
DIY cold air intake to cowl
24 lb/hr injectors (going to 27 lb/hr)

AW4 , for dyno runs I use a switch box to keep it in gear and lockup.

In addition to the power and torque, I've graphed the gains in power and torque (delta) and graphed some of the JTEC variables I record during the dyno pulls.

Old thread, lol, but any of you guys interested in a Dyno with a 258 stock and then compared to a 258 with a 4.0 head? I have those results.

Rustywolf wrote: ↑December 3rd, 2023, 8:39 am Old thread, lol, but any of you guys interested in a Dyno with a 258 stock and then compared to a 258 with a 4.0 head? I have those results.

I think you already know the answer.

Lol, well, I'm the newbie, so didn't want to step on any toes!!

I did this because it is a hot debate on my other forum about the 4.0 head adding 40 HP. For fun I even called Hesco and a gentleman there said it was the fuel injection, not the head. Most people just go by "feels", 15 years of debate and it only cost me $200 to figure it out, lol.
The details- 258 from my 89 YJ, first run is stock head-lower numbers. Second higher numbers are 4.0 7120 head.

31" tires, 38/38 Weber (4.5 Aux Venturis and slightly shaved/custom Emulsion Tubes), DUI HEI on both heads. The ONLY change was the head and carb tuning to match.

ONE THING TO NOTE----- These runs were done in 3rd gear, not 4th. The Dyno guy had a hard time getting the stock 258 to go up high enough, this mightve been me and my Carb tuning, dunno, I did AFR it and it was pretty strong, dunno. Was learning and still am. So both runs were in 3rd gear.

24rwhp & 23rwtq are solid gains for a head swap and well worth the effort. These are down to the 0.7:1 compression ratio increase as well as higher flow numbers.