Injector flow rate is not determined by engine displacement. Injectors are sized per power goal. When sizing injectors, take things into consideration like fuel type and fuel pressure. 24# injectors in a NA inline 6, running pump gas at max duty cycle (stock computer), will tap out at around 250 crank HP. That's a lot of work for only 50 HP. A well built NA Jeep engine with a standalone ECU and proper fuel system should make at or just over 400 HP. I'm not sure how well built the "S&J" units are however. Do they use stock rods and cast pistons? What compression ratio? Composite head gasket? Camshaft specs?

Jeep injectors are 60-14-14. Meaning 60mm long (o-ring to o-ring), and 14mm OD o-rings top and bottom. Every injector seller has them in every flow rate.

 

1999 - 2001 AMC Jeep Mopar 4.0L 288 C.I. L6 Stroker: 4.0L Block; Displacement: 4.7L/288 C.I.; Bore .040 - .060; Stroke: 3.906; Balanced rotating assembly; Firing Order 1-5-3-6-2-4; Compression Ratio: 10.1:1; Enginetech Main Bearings; Enginetech Rod Bearings; Felpro Performance gasket kit; Hastings Hypereutectic Dished Piston Rings; ICON Premium Forged Pistons IC944-040; Melling M-81A Oil Pump; SCAT Pro Comp Stroker Crankshaft 9-4.2L-3895 3.895" Stroke / 2.125 Snout .850 Pilot Hole; Horsepower 230; Torque 280 lb/ft typical; OEM-spec Camshaft-equipped (no computer reprogramming required), Performance Camshaft Available Upon Request; 45-degree oil filter mount (rel. to the oil pan rail) also got the redesigned cylinder head that has a way better casting

 

All the cheapest parts and no mention of connecting rods. Probably stock rods and a composite head gasket. It mentions a 3.906" stroke? and then the typical 3.895" stroke. Hypereutectic dish piston rings? Then forged pistons....? Stock camshaft? No cam specs? So this is just a stock engine? You could take the air filter out of a stock Cherokee and make the same power, maybe even more power. I wouldn't be surprised if they didn't just ship out a repainted stock engine. You might wanna tear into this thing to verify the parts before install.


Redesigned cylinder head? There haven't been many aftermarket cylinder head attempts for this engine. Are you referring to the ProMaxx head? That head is cast in China and is a direct copy of an OE head...

 

I've done plenty of research on that particular engine and it's good to me. Thanks for knocking on it before I even get it lol. And yes it's a recast redesigned head they made to stop the cracking issues with the 0331 casting number. None of that it's stock stuff it's aftermarket for the 4.2 .... that's how they get the "stroker " with using the 4.0 block...... if you ain't got nothing nice to say just stay off my thread. If you can do better than them then why ain't you? Man you can't go anywhere without running into a hater nowadays. I feel sorry for you and you having to live with that kinda attitude. Iono what world your living in but you ain't welcome in mine. Keep all that negatively to yourself coz I ain't having it