WHICH CAM?

I am getting ready to do a motor swap and I want to replace it with another H.O. 4.0 to replace the shot 4.0 i have now. I want to put a cam in it while the motor is out and im not sure which one to get, I also don't want to mess with the factory vacume system. The Crane Truck Power Camshafts duration is 260 int./272 exh. and the Erson RV Hydraulic Flat Tappet Camshafts duration is
280 int./288 exh. does anyone know which would be better for what I want?

here is the link:
http://store.summitracing.com/compa...94925232+4294924497+4294887637+4294886585+115

Dead link, but is one of these the ones you were looking for?

http://store.summitracing.com/egnsearch.asp?Ntt=jeep&N=4294908280+4294908279+4294840046+4294925232+4294924497+115+4294887637&Ntk=KeywordSearch

ya the first and third are the ones i was looking at.

GreenbeltXJ said:

I am getting ready to do a motor swap and I want to replace it with another H.O. 4.0 to replace the shot 4.0 i have now. I want to put a cam in it while the motor is out and im not sure which one to get, I also don't want to mess with the factory vacume system. The Crane Truck Power Camshafts duration is 260 int./272 exh. and the Erson RV Hydraulic Flat Tappet Camshafts duration is
280 int./288 exh. does anyone know which would be better for what I want?

here is the link:
http://store.summitracing.com/compa...94925232+4294924497+4294887637+4294886585+115

Click to expand...

Depends - what do you want?

While researching my book, I dug up some sixty-odd cams that would work for the AMC I6 series (they're all common on bearing dims,) so "which cam" is kinda open-ended, and if you're doing a performance buildup, you'll really want to map it out BEFORE you buy any parts!

I'm perfectly willing to help you get where you want to go, but I need to know where you want to go - and if you aren't sure yourself, how can you tell me coherently? There are a LOT more cams available for the AMC242 than you think - just check my JeepPower group for a sampling of camshaft data files for Dyno2000 (And, I can send you a copy of Appendix 12 for my book, if you like.)

5-90

there was just an article in jp about compcams cam. they put it in a stock 4.0 iirc. no mention of screwing with vacuum stuff. and a decent power increase

GreenbeltXJ said:

The Crane Truck Power Camshafts duration is 260 int./272 exh. and the Erson RV Hydraulic Flat Tappet Camshafts duration is
280 int./288 exh. does anyone know which would be better for what I want?

Click to expand...

Neither. If you're sticking with a 4.0L displacement, go for the Crane 750501 cam (248/260 advertised duration, 0.427/0.456 lift). It has the widest and best powerband for a 4.0 that's limited to 5250rpm with plenty of torque at low/medium rpm. Exactly what you want for a daily driver.
The Summit Racing part no. is CRN-750501. Yeah, I know it's $145 more expensive than the Crane 260/272 but you'd need to spend a lot more than $145 to buy matching valve springs/retainers/locks to go with the bigger cam. You can reuse the stock stuff with the smaller Crane cam.

Well, when I built up my engine I was in the same boat you were. I wasn't going to stroke it, yet while I had everything apart I wanted to do ''something''. I researched a ton of cams and this is the setup I ended up buying:
http://store.summitracing.com/partdetail.asp?part=CCA-K68-232-4&N=115&autoview=sku (you can buy just the cam here: http://store.summitracing.com/partdetail.asp?part=CCA-68-232-4&N=115&autoview=sku )

It's Comp Cams Xtreme 4x4 Camshaft with these specs:
Advertised Duration: 250 int./256 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.460 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.476 in.

For a DD this cam works out great for me. It pulls through the powerband nice and seemed to help more than I had thought (other factors in my engine build may have also added something however). Anyway, the power is 'right there' down low and much better on the lower end. Search alittle more find out what you really want from the new power plant and that'll help decide which cam.