hemi

maybe al .a. or others could help me whats the weight of a new gen. prostock hemi how to idenfiey the good heads from bad heads and how increasing 500 ci. to 565 ci. could increase less maintenence

Pro Stock motors aren't Hemi's, haven't been forever.

Uh, What? Pretty sure they have been in the Mopar world for the last two decades. GM? No.

Pro Stock heads aren't anywhere near what a Hemi is, more like a chevy head.

From what little I know about them, they aren't the lightest thing you could use. Don't know that increasing c.i.d. would help in the buzz rpm required to really make beans with these things. From what I've heard from Al I think a lot of the maintenance issues are with the monster cams and valve springs.

I have an empty 99 block, bare heads, and pipes and a maninifold and man is it heavy.Very cool to look at. I was hoping to build one but you need to be really deep pockets to build one and deep pockets to maintain them.

Do you know if the block is Compact Graphite iron or cast grey iron?
I'm assuming aluminum heads, correct?

its grafite block-aluminum heads

Current engines have either a mirrored head, or a symmetrical head.

There are Hemi '99 and '06 heads, I believe they look fairly similar.

I recall Al or someone mentioning that there was a version that ran 4 bolts or there abouts, per rocker arm. These were the one's to get, earlier versions would pull the threads out.

There is a bit of this stuff now these days, most guys aren't brave ($$$) enough to step up to it.

Both those heads more remind me of a boss 9 Ford in the chamber than a chevy.

I'd be more inclined to do anything other than try to make that platform work in anything other than ps.

I've seen fast ones that are larger inch for sure, but every single aspect of those motors was optimized for 500 inch na racing. The money, and effort to keep one on boil is demanding. They need cam, and rpm to work, and it's narrow rpm window. There isn't much torque either.

Having budget to run one, I'm sure it's a blast to zing something to 10 grand every shift, and pass, but you'd go faster, for longer, for less, with something less exotic imo.

They are HEAVY HEAVY engines....Ours weighed 885lbs ready to drop in the car, top to bottom end to end.

There are Asymmetrical and Symmetrical port versions of the head. All the Symmetrical port stuff will have multiple rocker stand hardware. The Asymmetrical port stuff is way more common and is where you will find a "good" and not so good layout. The difference is rocker stand hold down the not so good stuff uses a single bolt to retain the rocker stands. The "good" head uses multiple hold down bolts for the rocker stands. I know people who use both successfully.

The blocks have EXTREMELY short decks. Since that is whats preferred in Pro Stock where they were designed to work. The NMRA stuff is 4.9" bore space so they can go to 4.700"+-, makes power. The blocks cannot hold a lot of stroke and from what I understand 560"+- is about all you can get without a custom block. There are also Goodwin versions of the 99/06 Hemi that are built around a 5" bore space. Seems he builds them to 655" for the most part.

As for maintenance, yeah its definitely more than your average bracket engine. The stuff was designed to work at high RPM. You will end up replacing springs on a regular basis and also the seats will likely need to be touched up fairly frequently. And that was running one at WAY less RPM than Pro Stock does.

The blocks also come is a few versions. The preferred one being the 9 cam bearing version over the 5 bearing ones. They also have skirted and unskirted varieties. Unskirted ones are all 9 bearing. The block are made from Compacted Graphite

I think Diablo had one of the Goodwin 5" engines built for his pulling truck. The heads looked similar to the 99 Hemi stuff. I think the 99 Hemi's flow well north of 600 cfm, so at 500" (even at 560") you'd have to spin the piss out of it

They are basically carbon copies on a 5" bore space.Yes he has one as does another member here with one in a 68 Barracuda. I have seen the dyno numbers from Goodwin, hard to quantify in a pulling truck to me what those numbers mean. As for the car Ill let the owner speak to that.

A Goodwin 99 also I believe won the NA class at drag week in a Camaro. Don't know the details but it was in the 7's and had an 8.0x average from what I recall...

We have had both one of Goodwin's 5" Cast Hemi 99 motors and now his Billet 5" Hemi engine.

Maintenance on any of them isn't for the faint of heart but if you stay up on it then they are pretty happy motors. Full refresh comes at 45-50 Truck pulling runs.... about every two seasons for us. Valve springs are ever 12-14 runs (truck pulling runs).

And for RPM's even at 650ci our Cast 99 Hemi peaked at 8000 and we ran it around 8600rpm, and the new Billet one peaks at 8400 and we run her right around 9000. So even with the big cubes they still want to turn!