94XJ4x4
NAXJA Forum User
- Location
- Bitburg, Germany
Jeep made a 4.2 and 4.7 liter I6? http://jeephorizons.com/tech/#Stock under stock specifications. is this web site bogus or have i just not been paying enough attention?
also... neither was available in the XJ line. 4.2 IIRC showed up in YJ's while the 4.7 showed up in ZJ's or WJ's (don't remember which)4Banger said:The 4.7 is a V8.
True, but here we're talking about the 4.7 in relation to a page that lists it as a "1999 Jeep 4.7 Liter engine" Also aren't there 4.2 strokers out there as well?old_man said:You may see 4.7L's talked about on the forum associated with XJ's. Normally that means that somebody took a 4.0L and made a stroker motor out of it.
Ed A. Stevens said:The factory 4.7 is sometimes called the Mexican stroker, an early 80's vintage factory experiment with 4.2 crank and an almost 4.0L bore, (reported to be) assembled to provide adequate power at the high altitude of Mexico City. The pistons were rough full circle dished castings with fairly low compression and none of the quench attributes of the combined 4.0L piston and head chamber. A few appear to have made it into US vehicles in J-trucks and SJ Waggoners (another Jeep, whatever's in the parts bin, thing). They are actually more like 4.5L in displacement, and they are very rough compared to a modern 4.0L stroked with the 258 crank (an example of what 20 years can do).
No, because not many people base the engine on the 4.2L block. The so-called "stroker" engine is made up using a 4.0L block and a 4.2L crank. At stock 4.0L bore it is 4.5 liters, but at 0.030 over (which is probably the minimum you can get away with when rebuilding a block) it comes to 4.6 liters, and if you bore it 0.060 over it's 4.7 liters.explorer said:That would be a simple bore job, not a stroker, as it uses the original stroke crank. The displacement is closer to the 4.5, not 4.7. People building the 4.2 sometimes bore to 4.0 dimensions and use the 4.0 head, resulting in the 4.5 w/ significantly more power when combined with the modern fuel inj.
Eagle said:No, because not many people base the engine on the 4.2L block. The so-called "stroker" engine is made up using a 4.0L block and a 4.2L crank. At stock 4.0L bore it is 4.5 liters, but at 0.030 over (which is probably the minimum you can get away with when rebuilding a block) it comes to 4.6 liters, and if you bore it 0.060 over it's 4.7 liters.
It was, essentially, a 4.0L block -- before the 4.0L engine existed. It was a 4.2L (258) block built in a Mexican plant, cast with extra-thick cylinder walls to allow it to be punched out to 4.5 liters in stock form. As Ed posted, it was crude, the pistons were slugs made by a Mexican company and when a former member of the Yahoo Strokers e-Group (now deceased) bought a replacement to study as a possible piston for use in stroker 4.0L engines, he reported it was so rough it almost looked like it was hand made.explorer said:Let me understand this. Your saying that this "mexican" block was a 4.0 block before the 4.0 was officially introduced? Im confused. If it a 4.2 with a 4.2 crank, and overbored to stock 4.0 bore then its a 4.5 but not technically what I would call a "stroker".