budget 4.5L stroker Q

[POLAR_JEEP_04]

Ok I blew the motor up in my 97 xj trail rig (4.0) a good friend of mine found a cheap complete 99 4.0 out of another XJ. With a spun rod bearing. I have a 4.2 crank from a 76 CJ. I am planing on getting 4.2 rods and putting the stock 4.0 pistons on them and using the 4.2 crank. Ill be replacing all of the bearing and seals and I have 8.5mm wires, msd coil, lt1 injectors, 99 intake manifold, apn header, and if I have the time and money I am going to gasket match the head and have my throttle body bored. Ill be using the stock cam but I'm replacing the timing set since ill have the motor out. Is there anything else I need to do to make it run right? Deck the block? Thicker head gasket?

 

[bigdaddyjlove]

Everyone says decking the block will help get your quench right and will make the motor more resistant to detonation. On the advice of my machinist, I did not deck the block, but I did choose a cam with a little more overlap, and I have been fine.

 

[POLAR_JEEP_04]

So I should be good? I plan on boring it and caming it sooner or later so I would just do the decking then. Right now I just want to get it on the trail but I don't want it to run like crap and be under powered.

 

[bigdaddyjlove]

Actually I think you should look at a cam swap. The right cam can lower your dynamic compression ratio and help with detonation. A cam is pretty cheap, and they are a pain to swap with the engine in the jeep.

 

[POLAR_JEEP_04]

The cam is cheap but the valve spring, retainers, lifters, and seats are not. What cam are you running and where did you get it? Where did you get the springs and all the other stuff for it?

 

[bigdaddyjlove]

The cam is a Crane (PN is at home)Bought from Advance Auto, +- $180.00. the springs are stock Jeep, and the lifters are Crane Racing. If I had to do over, I'd go with stock lifters, the Crane ones are loud. Broke in with rotella and STP (lots of zddp) and I have had no problems. I have also put that cam in two other stock 4.0 and have been very happy.

 

[POLAR_JEEP_04]

Yeah let me know what cam that is. If I can use stock springs that's the route ill go. What else do you have done to your motor

 

[bigdaddyjlove]

I've got two. One runs Ford Racing 24 lb injectors, the other runs LT-1 injectors from a 96 Caprice. I have had to do very little to make mine run right so far. I am swapping one of them into a '01 XJ next weekend, so I'll se how it goes.

As for the cam. I am trying to find the book I put together when I built the engine. I got married and moved into my wife house in the meantime, and I can't find a dammed thing.

 

[POLAR_JEEP_04]

would this be a good cam if i bought some cam saver lifters from summit or jegs?

http://cgi.ebay.com/ebaymotors/Comp...r_Truck_Parts_Accessories?hash=item3efe05dacb

 

[bigdaddyjlove]

I'm not good enough with cams to look at the specs and tell you whether its a good choice or not. Sorry. I had a good machinist help me pick.

 

[gradon]

The specs look good--similar duration on in/ex as the 96+ cams, but with increased lift, so should play nicely with pcm. You should ask for a p/n or look at comps site to figure out which one it is.

 

[Dr. Dyno]

would this be a good cam if i bought some cam saver lifters from summit or jegs?

http://cgi.ebay.com/ebaymotors/Comp...r_Truck_Parts_Accessories?hash=item3efe05dacb

That's the CompCams 68-232-4. Good choice for strong torque from off idle to 4500rpm, and the wide 113* LSA promises good idle quality.