Anyone know what the stock flow rate of the injectors on the 3.7L is?

I have been looking around but cant find anything other than the part numbers..

looking to prepare a turbo setup for next summer and trying to figure out what injector size I will need to the setup I am going to be going with.

looking for either cc or lb, doesnt matter.

Unless your tearing apart the engine and replace the stock pistons with forged ones your wasting your time and will blow your engine at the same time.The 3.7's pistons can not handle boost as the top piston ring is to close to the top for emission reasons and will break the pistons under boost.KenneBelle learned this fact with there supercharger system running only 6psi boost,they scrapped the whole kit for the 3.7 real fast.

thanks for the concern, but that has nothing to do with my question..

i know what the risks are, but i can't find a single instance of someone who has actually HAD a boosted 3.7L anywhere or any documented reasons of exactly WHY any may have failed..

the only 3.7L that i have found that has been toasted due form high power was KJ Liberty on a 125 shot and it wasn't even pistons or the crank failing.. it was because of tuning.

there are 4.7Ls boosted and they use pretty much identical pistons (as far as top ringlands) alot of modern pistons have top rings that are close to the top of the piston and run boost without issue.

and btw, im talking 5-6lbs of boost, with good tuning; not just cramming 6lbs of boost with the stock ECU and fuel system.

if anyone has insight on the stock fuel size, that would be great, otherwise i guess ill buy a new one and get it flow tested. looking to figure out what sized injectors i should look at getting for the project.

24lbs/hr @ 252cc/min

some manu's like GB sell 22's

there are XF2E's which will fit but they're in the 30's and upgrading the fuel pump is another can of worms

for those of us who have seen the 3.7 internals, we wouldn't put more than 2psi boost on it, adding a turbo is not only going to be a piping nightmare but a tuning nightmare and in the end you're going to end up spending several grand

your first step needs to be contacting B&G as you're going to need one of their ECM's and want their TCM, at least consider converting the sparks to MSD6 which is a good chunk as well

the stock TB barely keeps up with NA airflows, so get with dan arcand at fastman throttlebodies


the 3.7 isn't something you can smack a tarblow on and roll, without doing the above chances are you'll never get it tuned


the reason why boosted 3.7's fail is because the ring lands are too high on the piston and too soft, which causes fractures and disintegration of the piston and ring at lower than 6psi, there's just nothing there, N/A they'll pretty much last forever but like the fuel pump and other things, it's on the edge of it's limits while being appropriate for the designed application

anyway, i digress..

if you're looking for what sized injectors you should look at, you're not looking for a particular flow injector, you'll need a kit which usually comes in a range of 3 to 6 spread, and it's something B&G should be able to give you a very good idea of which range you'd be looking at

if you're finding yourself interested in taking shortcuts and are intent on keeping the 3.7 and not doing an engine swap and don't want to deal with an R&R of the internals, then listen to Troy, I know he didn't answer your question, but he was just trying to save you a headache, and a hurt wallet

bottom line, it's your jeep and your money. We do our best to help people keep from making uniformed mistakes, but in the end it's up to you

_________________
03 Renegade (Black)
177k miles 3.7L gas - 45RFE
Command Trac / 4.10s
Lift: ft. 790+ rr. JBA4+
The last of the TrailReady Front&Rear Bumpers and TR Rock Rails
Jarhead Offroad light covers
31x10.5R15 RedLetter Grabbers on Blackrock Dunes
L.O.S.T #KD098632

Call KeeneBell,I imagine they have the inside scoop on boosting a 3.7 and why not to.

When I tried to order one from KB they told me they weren't going to produce it since it required making a custom intake manifold and they would never sell enough of them to justify even doing a single manufacturing run.

As far as the stock injectors are concerned the 02-03 use:
#53031099 24.0lb/hr @ 49psi

Not sure about the specs for 04 and later.

Even though I didn't have a piston failure, I would still highly recommend getting some custom pistons made. Won't be hard since they are the same bore as 4.7 pistons.

edit:
Here are the stock cam specs. You're probably going to end up needing them.

Duration @ 0.050" lift I/E: 194*/199*
Valve lift I/E: 0.402"/0.390"
Valve overlap: 67*
LSA: 112*, ICA: 112*, ECA: 112*
IVO: 15*ATDC (0.050" lift)
IVC: 29*ABDC
EVO: 31*BBDC
EVC: 12*BTDC

_________________
June 2001 Liberty Limited 4X4
Frankenlift II Premium, Al's Upper Arms, 245/75R16 C Silent Armors on Moabs, RL Skink Super Sliders, Rear DTT, Riddler Diff Cover, Fastman Throttle Body, Profinish-Proglass Hood, Borla Dual Outlet Exhaust, TransGo Reprogramming Kit, APS Stall Converter, 4.10 Gears, B&G Chrysler PCM, Lots of Line-X, etc...

I'm not 100% sure on this info, my memory on it is a bit foggy and I don't have the particulars on the #53031099 injectors with me here in chicago

however, there is a #53031099AA injector as well and I don't remember what the differences between the #53031099 and #53031099AA were

but just a heads up on that, pretty sure their flow rate is the same

_________________
03 Renegade (Black)
177k miles 3.7L gas - 45RFE
Command Trac / 4.10s
Lift: ft. 790+ rr. JBA4+
The last of the TrailReady Front&Rear Bumpers and TR Rock Rails
Jarhead Offroad light covers
31x10.5R15 RedLetter Grabbers on Blackrock Dunes
L.O.S.T #KD098632

i emailed kenne belle a while back and the response that I got was pretty much that it didn't really go past the prototyping stage because there wasn't enough interest and it would have cost to much to get any interest.. i'll see if i can dig up the email.

I specifically asked in the email if there were engine failures and what caused it, etc.

getting pistons made would be easy, and relatively inexpensive, but having them installed would be the part that would be a pain in the booty.

piping won't be a nightmare at all, would actually be fairly simple.. remote mounted system to replace the muffler with a 2-2.5" charge pipe coming up to the throttle body. at 5-6lbs of boost, and the longer charge piping running under the car, an intercooler will not be necessary at low psi.

the comp ratio on the 3.7L is i believe 9.1:1 which would only make the compression ratio aroun 12.8:1 at 6lbs of boost..

thanks for the answer on the flow rate of the stock injectors as well as the fuel pressure!!

o, one more question.. anyone know off the top of their head if we use a high imp or low imp injector?

also don't really understand how tuning would be a nightmare, my only real worry is how the transmission will do with the added torque if i don't go B&G. B&G can do a flash and there is always the AEM FIC. but with B&G, gotta send in ECU, have the VIN flashed or w/e and its just an 'over the phone' tune. with the AEM you can log, make adjustments, etc. without having to send the ECU back and forth.

You don't have to remove and send your ECM to B&G for the flash. Call and explain exactly what you are doing, what you want and give them ALL information. They will flash an ECM and charge you a core charge which is refunded when you return your old one or you can keep the stock one and let them keep the core charge.