will a stock style intake fit an off center stage motor?

[turbotony1]

I'm sorry, but here we go again, beating the crap out of the dead horse!
My question is similar to ones that have already been asked. I'm scared to buy an on-center block because I don't know exactly what will transfer over and what won't. I searched through many past threads, including this one. I have read that the on-center is stronger. That's why I'm looking into it.

I'm the guy who posted last week about my Stage II 3.8 off-center block being cracked. (Thanks to all who commented. It really helped me out!!)

I'm thinking about buying a 4.1 on-center block. The heads, as stated in my last thread, are ported M&A stage III heads. Intake is stock style, but bolt holes are elongated and every runner has extensive work done. Sod at Hye Tech, who built and ran it, said he ran this intake on an on-center block too. If that is the case, and it will fit and on-center block, what other items will need to be converted on the top end?

The rotating assembly consists of a 3.590 BMS crank (un-cut), Cunningham I beam rods and JE 3.8 pistons. From what I've read, I will need on-center rods and bigger pistons.

How about the front cover? I've heard people say that there are stage II front covers, if so, will I need a different front cover for an on-center stage II block?

Thanks,
Anthony

 

[Mike E]

I'm not real knowledgeable about the M&A heads, but that intake appears to be setup for an on-center block. And if that is the case, it would not have ligned up with the ports correctly on your off-center block.

You can use that stock style timing cover if you have it cut down .120" on the gasket side.

 

[forcefed3.8's]

On center engines don't have any wet sump oil ports. The early on center blocks, 4 bolt center, 2 bolt ends, have the pad just like the off center blocks have. So, an early on center block will require minor machining and the pick up from your off center will work. The later ones, 4 bolt center cross bolted 4 bolt end, even later 6 bolt cross bolted center 4 bolt cross bolted ends have no pad for wet sump.

The front cover won't need machined if you get the dist gear spacer made for an on center engine, and space the balancer out .120.

If the intake works with your off center engine, and already had oblong holes, then it won't work with those heads and an on center engine. A stock intake has small enough ports that it can be ported and the holes can be oblonged to work with an on center engine.

 

[turbotony1]

On center engines don't have any wet sump oil ports. The early on center blocks, 4 bolt center, 2 bolt ends, have the pad just like the off center blocks have. So, an early on center block will require minor machining and the pick up from your off center will work. The later ones, 4 bolt center cross bolted 4 bolt end, even later 6 bolt cross bolted center 4 bolt cross bolted ends have no pad for wet sump.

So, if it's a late production on-center, it has no provision for wet sump. Could a good knowledgable Buick machinist make a late production block into wet sump? Or would it be cheaper to buy a dry sump system?

Are the 153's the "late production block" that your talking about? or are there early and late production 153's? Which would mean I will have to check with the seller before I buy.

Thanks,
Anthony

 

[Squid4life]

Late production on center = no oil provision, you are correct. No idea if someone could make it into wet sump internally, but your simplest fix to make it wet sump is to use a Duttweiler/TA/Whites perf oil pump setup that uses gears and a stock front housing, but picks up the oil from the bottom of the pan via external hose. So, the pan would need to be a wet sump, or have a sump added, run the pickup hose from pan to pump. If I remember correctly there are 2 other lines on the pump, one which I think goes to a fitting added to the fuel pump blockoff plate on the drivers side, and I forget the last one... I am brain dead from driving all day but sure someone else will add to the thread...

 

[forcefed3.8's]

So, if it's a late production on-center, it has no provision for wet sump. Could a good knowledgable Buick machinist make a late production block into wet sump? Or would it be cheaper to buy a dry sump system?

Are the 153's the "late production block" that your talking about? or are there early and late production 153's? Which would mean I will have to check with the seller before I buy.

Thanks,
Anthony

All oncenter engines are 153's. If it has any cross bolted mains (bolted from the outside of the block), it has no pad for the oil pickup. The passenger side outer bolt on the front main goes through where the pad/ passage would be. The Dutt/TA/White set up has a 12an feed from the pan, 10an to a remote filter, 10an back to the engine feed port (either on top by the lifter valley, of on the side of the block), and the Dutt/TA/DLS version has a 6an bypass. The White racing has an internal bypass.

 

[turbofabricator]

I just built an on center stage II with TA aluminum heads and a Champion stock style intake. (New aftermarket casting based on the stocker, but it needed alot of port work to align properly, too) I used a TA high volume oil pimp cover with a -12 AN feed from a fitting welded to the pan and -10AN to a Precision remote oil filter and a -10AN from filter to the side of the block (1/2" NPT fitting that I welded an extension onto to fit past the side of the block) If you need any advice or help with custom oiling parts drop me a PM for my phone number. Doing the on center engine upgrade is pretty straight forward as long as you have a deep wallet. Everything costs $1,000 it seems.