Going to get started soon

[optmaxx]

I should get all of the parts to the machine shop sometime this week, so here's a list of what I have going on.
-4.2 crank turned 0.020

- '96 Block bored 0.020 and honed

-944 pistons 0.020 and 4.0 rods

-'96 stock cam

Is there anything else I need to do? I should be running 91 octane after this right?

[jeepxj3]

Deck the block 0.020" to get a better Quench.

[Cheromaniac]

Deck the block 0.020" to get a better Quench.

..and run 91 octane. The SCR will end up being around 9.6:1.

[jeepxj3]

Or get the correct dish volume and CR you want.
IDK maybe 26cc dish will give you 9.2:1 and 0.043" quench and run on 87 octane.
or 28cc dish and 58cc combustion chamber is 9.06:1.

Today, custom spec parts are more easily available. Don't settle for off the shelf parts which compromise your goals.

[Cheromaniac]

Or get the correct dish volume and CR you want.
IDK maybe 26cc dish will give you 9.2:1 and 0.043" quench and run on 87 octane.
or 28cc dish and 58cc combustion chamber is 9.06:1.

Today, custom spec parts are more easily available. Don't settle for off the shelf parts which compromise your goals.

You've obviously seen this:

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Custom forged +0.020" bore pistons, compression height 1.380", dish volume 26cc
9.25:1 CR
Stock 4.0 camshaft
Ported HO 1.91"/1.50" cylinder head
Mopar/Victor 0.043" head gasket
0.043" quench height
Accel 24lb/hr injectors for '96-'04 engines
245hp @ 4800rpm, 315lbft @ 3000rpm ('96-'04 camshaft)

[jsawduste]

Today, custom spec parts are more easily available. Don't settle for off the shelf parts which compromise your goals.

jeepxj3 wins today !!

[optmaxx]

I saw that thread too, but I had my 944s already. All of that sounds awesome, but I don't know if I can wait another month or more to get my money back, and order the custom pistons. So, I'll get my block decked 0.020, I'll definitely get the 24lbs injectors though. Are there any benefits with the set up I'm going to run? I mean with my 944s? Are there any mods that can be done to the 944s?

[optmaxx]

If I deck the block, would I need new push rods?

[Cheromaniac]

If I deck the block, would I need new push rods?

Probably yes, but you could assemble the engine with your existing pushrods and check the lifter preload before you pull the trigger.
In the meantime smoothen the combustion chamber surfaces, polish them as much as you can, and feather any sharp edges to reduce the risk of pinging.

[optmaxx]

I've been thinking about, and I might go with the custom pistons. The extra work that comes with 944s aren't worth it, and it'll be cheaper in the end to get the custom pistons. I don't want to deal with figuring out that lifter preload unless I'm installing a new cam. Guess I'll try to sell my 944s or return them, It's going to be a rough month .

What should I tell the piston makers what I want.

[optmaxx]

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Custom forged +0.020" bore pistons, compression height 1.380", dish volume 26cc
9.25:1 CR
Stock 4.0 camshaft
Ported HO 1.91"/1.50" cylinder head
Mopar/Victor 0.043" head gasket
0.043" quench height
Accel 24lb/hr injectors for '96-'04 engines
245hp @ 4800rpm, 315lbft @ 3000rpm ('96-'04 camshaft)

Would you recommend I place an order for those type of pistons for my set up? Will this allow me to use 87 octane, and the block will not need to be decked? I have a'96 block, bored 0.020, I plan to use the '96 cam, and nothing special will be done to the head. I plan to order from Bulltear, and I have the Victor Reinz head gasket, I just not sure what size it is.

[Cheromaniac]

Would you recommend I place an order for those type of pistons for my set up?

Yes.

Will this allow me to use 87 octane, and the block will not need to be decked?

Yes x2.

I have a'96 block, bored 0.020, I plan to use the '96 cam, and nothing special will be done to the head. I plan to order from Bulltear, and I have the Victor Reinz head gasket, I just not sure what size it is.

The Victor Reinz head gasket is exactly the same as the Mopar Performance version so it has a 4.00" bore and a compressed thickness of 0.043" (1.1mm).

[optmaxx]

I was going to order the ARP connecting rod bolts, but the ones I would find were around $100 online. Is that correct cause it seemed a bit much to me? What is the part number for these bolts from ARP and is it necessarily to get ARP connecting rod bolts ?

[Cheromaniac]

ARP-112-6001 and Summit Racing have them for $53. Definitely a must have in my view.

http://www.summitracing.com/int/parts/arp-112-6001

[optmaxx]

My Bulltear pistons came in, awesome. I still have the 944s, I've tried emailing RPM to let them know that I want to return them, but I might have to call them because they haven't gotten back to me, so I decided to take a side by side picture of them. I'm doing a check list to make sure I got what I ordered, everything seems to be correct but I can't find where it would say the overbore size. I wanted to get 0.020 pistons, so on the box it says bore diameter 3.895 and on the pistons I found some numbers that read 030-4 on the bottom, and I'm not sure if that has anything to do with the overbore size. Also, the shape of the top is circle on the Bulltear piston, that's fine right? Here's some pics.