Jeep Strokers

Hey everyone this is my first post here. I’ve been reading posts here for awhile now and I think I’m ready to pull the trigger on building one myself. I plan on using Cheromaniacs recipe but I had a few questions.

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Custom forged +0.020" bore pistons, compression height 1.380", dish volume 26cc
9.25:1 CR
Stock 4.0 camshaft
DIY ported HO 1.91"/1.50" 57cc cylinder head
Mopar/Victor 0.043" head gasket
0.043" quench height
Ford 24lb/hr injectors for '87-'95 engines, Bosch 0280155703 injectors for '96-'04 engines, '98 Chevy LS1 25.2lb/hr injectors for '05-'06 engines
249hp @ 4900rpm, 303lbft @ 3500rpm ('87-'95 camshaft)
245hp @ 4700rpm, 315lbft @ 3000rpm ('96-'04 camshaft)

-Will this work with a Renix engine and keeping the Renix fuel injection system?
-Will I be able to run this on 87? I’m 1131ft above sea level
-What Hp/Tq numbers am I looking at if I keep the Renix valve train?


Thanks for the help, Andre

I'm here Andre.
You can certainly use your Renix head and EFI system, and this combination should have no problem running on 87 octane.
Naturally power numbers will be lower because the engine's breathing will be more restricted; more like 210-215hp & 290-295lbft and you'll need smaller injectors (21lb/hr @ 39psi).

Ah ok, that much of a increase almost doesn’t seem worth it. I do have a 94 4.0 that I was hoping to be able to sell but I can probably switch some stuff.
-Would I be able to just switch the whole head onto the 87 block?
-Would I need to swap camshafts as well?
-I should use the 94 intake and exhaust right?
-Will the 94 throttle body work with the Renix system?
-Would this make much more power or is the Renix still limiting it?

Sorry for all the questions, just wanna make sure I get it set up right.

You can swap the HO head, intake manifold, throttle body, and exhaust manifold onto your Renix engine. The camshaft is the same. With those parts you'll gain about 15hp, maybe 20 if you opt for a bored 62mm throttle body, so you'd be closer to 230hp.
You'll need to adapt the Renix TPS to fit onto the HO throttle body to make it work though. The HO exhaust manifold also doesn't have EGR so you'd need to delete your EGR system.

Ok, just a few more questions and I think I’ll be set.

-Where would I go about getting a set of pistons for this setup?
-Since I’m using the HO parts now would I be using the 21lb/h injections or the Ford 24lb/h?
And finally, the connectors look similar so would I just be able to plug the HO IAC into the Renix or are they different internally?

The IAC should be plug n' play.
For pistons I suggest you contact our resident guru Russ Pottenger, and a set of Accel 24lb injectors (flow 22.7lb/hr @ 39psi, part no. ACC-150124) should do nicely.

Anthi4078 wrote: ↑January 14th, 2023, 7:00 am Ok, just a few more questions and I think I’ll be set.

-Where would I go about getting a set of pistons for this setup?
-Since I’m using the HO parts now would I be using the 21lb/h injections or the Ford 24lb/h?
And finally, the connectors look similar so would I just be able to plug the HO IAC into the Renix or are they different internally?

Hi Andre,

You’re welcome to reach out to me with a phone call or email and I’d be happy to send you some information and pricing on my pistons and other related stroker kit components.

Thanks,
Russ Pottenger
Bishop-Buehl Racing Engines
531 N. Lyall Avenue
West Covina, California 91790
Work (626) 967-1000
Cell (626) 673-2203
Email: [email protected]

Hey it’s been a bit since I replied to this but I’ve been thinking and I’m wondering if it would be worth it to switch to an aftermarket cam? Thanks, Andre

Unless your original stock cam is in exceptionally good condition, a mild performance cam swap would definitely be worthwhile.

Yeah I’d imagine its not at its best at 250,000km What cam would you recommend for the the setup I have planned?

You could run Russ Pottenger's lower valve lift version of the CompCams 68-232-4 camshaft with new OEM valve springs.

Ok, what’s the benefits of the lower lift? I should probably mention that this motor will spend the majority of its life on the street so I’m not aiming for a off-road oriented setup.

"Lower lift" just means you have the fun of a cam without the bill of the machining

Ah ok, what kind of HP/TQ gains should I expect from Russ’ cam?

5 HP & 5 Ft# with stock ECU and fuel system