WHAT YEAR TO REBUILD?

[RIOT13]

OK so the start is here
i have a 258 crank 12cw (already been turned, both the rod and mains made .10) from a 79 258
258 connecting rods (#707)
24lb injectors on the way
newer intake on the way


I NEED AN ENGINE.. i would like to know your opinions on what year block and head to use. mind you this vehicle will be a daily driver all year round but will be taken off road also. I am looking for more of an on road vehicle. I will most likely have emissions to pass. i would like narrow it down to a single year to just go pick up from a junkyard.

advice would be appreciated but i would like an explanation as to why you suggest one year over the other...

thanks

[IH 392]

Get one from the same year as your Jeep, assuming that it is an OE 4.0 Jeep?, you didn't say what it's going in???
There are bock specifications in the FAQ's, all of them are suitable to build strokers on, some will fit right in your Jeep and some won't!

[RIOT13]

wel thanks but i still dont know what it is goin in yet but wil most likely will be a xj cherokee

[SilverXJ]

Best bet would be a 97-99 XJ block. Still, there are slight differences between the years on the XJ

[RIOT13]

so what are the differences?

[amcinstaller]

in the head, some port location and shapes, as well as coil pack mounting.

in the block, accessory and motor mount locations, as well as a cam difference, and main stud girdle

[gonridnu]

I chose a 96 -99 NVH block #53020569 and head# 0630 for a couple reasons....

According to this site the NVH (Noise, Vibration, Harmonics) block has additional material in the main web area and utilizes a main stud girdle that runs the length of the block...sounds good to me. I have not read anywhere that there is a problem with these blocks.

I also found this was the first casting that has dowel pins positively locating the cylinder head. My earlier block and head did not have these and there was no material there even if you wanted to add them. Again, this seems to be a positive.

The #0630 head has the dowel pin receiver holes and is a raised port design similar to the "HO" head so I pretty much ran with this combination and as far as I can tell it appears to be as good as it gets utilizing readily available stock parts.

[RIOT13]

are there any blocks that can be used in a wrangler and xj that have the same mounting locations and would be drop ins.. i might end up goin with a late 1990's wrangler

[RIOT13]

OK the project car has been purchased.

2000 xj sport

what are my options for blocks and heads for this engine build?

[Plechtan]

You will need a 1999 and up block if you want your accessories and motor mounts to work. You will need a aftermarket head ( not a good ideato reuse a 331 casting) with coil pack mounting bosses.

[live24wheel]

Ok now I am left with a question. Motor mount differences? I know there will be some accessory mounting issues to work out, however im not sure exactly what though. Im using a 97 XJ block and going to be putting it into my 2000 XJ as well. What are the motor mount differences? I was under the assumption all the XJ's used the same motor mounts and what not... I will probably run Brown Dogs motor and frame side mounts but am I missing something here?

[RIOT13]

ok what after market heads are out there for this engine? with the coil mounting bosses?

[SilverXJ]

I think the motor mounts should be fine. Brown Dog, the company that makes motor mounts, said they were the same.

As for heads, not many. If you want the coil mounts you will need a 0331 or Hesco's Aluminum head. So you have 3 options: Hesco, Alabama cylinder head 0331, or a 2003+ stock 0331 head.

[Plechtan]

The motor mounts are the same from 1985-2001 on the frame. The ones that bolt to the block are different from 1999 and up. they also use metric bolts. The water pump is different on the 1999 and up block, It does not have the 2 tabs to mount the PS pump. take a look at one n a vehicle before you just decide to use one.

[SilverXJ]

The motor mounts are the same from 1985-2001 on the frame. The ones that bolt to the block are different from 1999 and up. they also use metric bolts. The water pump is different on the 1999 and up block, It does not have the 2 tabs to mount the PS pump. take a look at one n a vehicle before you just decide to use one.

I think you are referring to WJ/TJ blocks with the major changes, not XJ blocks.