New guy with a .030 over block.

[xj bmx]

I just got a 92 block and head to start my stroker build. it was rebuild "2k" miles ago and is bored .030 over, ive been stalking the you guys for a wile alog with some other sites and it i read a Under square motor will make more low end power, and i read that going .040 over will cool the best? Im just wondering if i should go to .040 or maby even .060?

As for what the motor will be used in
It is a 92 Jeep Cherokee 4.x-AW4-231 and will be an off road rig only and will be driven to the trail.

[SilverXJ]

and i read that going .040 over will cool the best? Im just wondering if i should go to .040 or maby even .060?

There will be no noticeable cooling difference between .020, .030, .040, or .060". I know where that info came from and that guy is a hack. He contradicts himself a lot from that recipe and what he actually posts.

[xj bmx]

Ya, that's what a lot of guys said about that dudes recipe, that was just one of things that sounded like it made sense.

[amcinstaller]

also have your block checked to see if itll even like .060 over. some dont and actually wont cool good at all, iirc.

[IH 392]

Typically an engine will run hotter with a bigger over bore, some engines are worse than others, some don't seem to mind at all, but never seen one that "cools better" with more over bore????

[Cheromaniac]

I just got a 92 block and head to start my stroker build. it was rebuild "2k" miles ago and is bored .030 over, ive been stalking the you guys for a wile alog with some other sites and it i read a Under square motor will make more low end power, and i read that going .040 over will cool the best? Im just wondering if i should go to .040 or maby even .060?

As for what the motor will be used in
It is a 92 Jeep Cherokee 4.x-AW4-231 and will be an off road rig only and will be driven to the trail.

Have the cylinders bores checked out and if they're still round & true, there'll be no need to rebore them again and you can stick to +0.030". Since the engine will be going into an offroad rig, you'll want it to be biased towards producing strong torque at lower rpm. You could take a look at my "recipes", see which one comes closest to your needs and budget, and make a copy (or close copy) of it.

[lafrad]

Well, Check for good straight and unworn cyl bores. If they are all good (and they should be with only 2K miles on the clock), then just do a bottle brush hone to get a new crosshatch, get a new set of rings for the pistons, and run it.

there is ABSOLUTELY NO REASON to overbore a non-race application I6, unless it REQURES it for a clean bore. and if you do have to, only go as big as you NEED to, to fulfill a successful and inexpensive rebuild.

My block had 155K on it and had overheating problems in the end, so it was badly scarred... the 0.030" parts were the cheapest at the time (0.020" over was all it needed, but were $150 more for parts in the end), so I went 0.030". The block could have gone 0.060" (according to the sonic check), but this way I have lots of metal for block strength for long running with little wear, and also allow for a future rebuild if ever needed.

[xj bmx]

So there is a chane the walls haven't wore enough to be able to stroke and be ok? Well I'm pumped haha.

[lafrad]

you REALLY want to have a fresh crosshatch. Measure the bores, if they are round (or even just a thou or two out), you will have NO PROBLEM renting a bottle brush hone from autozone, putting it on your drill, spraying lots of oil down the cyl and following the instructions to put a new crosshatch in the cyl bores. After thats done (it should make the cyls look new) then clean up the block and put all your new stuff in! no overbore necessary (and you save some cash in the process)

you will be at 4.5L, but you really won't notice the 2% difference in displacement... you will run out of intake port LONG before that becomes an issue.