How much horse power is safe on a factory Hemi block with crossbolt mains? New block no fatigue.

No opinions?

My understanding, original iron blocks ran ~700 HP circle track (eg Daytona) and 1,500+ HP drag race. I'm guessing the blown drag race has been pushed harder also. Not an expert so consider this a "bump".

Curious why you ask?

Well way back in the days of the late 60's and early 70's. As stated that was all they had. I knew a guy who ran blown alcohol. He was claiming 1800 HP. His stock block made many runs at that level. Jim

I ask because I have a factory block that the bottom end is cross bolted and just like a Hemi but it is wedge top end. It has never been used , still at 4.25 bore. The consensus of the people I have asked and talked to is that it is an ex factory cast nascar block. I am going to build a stroker out of it 4.50 stroke crank. I am going to put it my challenger for drag week. And was just wondering how much more this bottom end will take over the standard 2 bolt main block

A bunch I would bet, try and measure the thickness of the main webs and then go to 440 Sources web site and see how your block compares to the other RB blocks they have listed

Bob Banning Dodge used to get about 90 runs at roughly 1800 hp on 80% nitro in their funny car back in the 70s. They would typically crack in the main saddles. When you had to chisel the main bearing out because it got drawn up into the crack it was time to replace the block.

Then I should be way safe then!!!
Thanks
Has anyone else ever seen a factory block like this?

They've been discussed on Moparts in the past, but I've never seen one. Id guess you'd be close to what a mega block could take. Very cool piece, what's the back story on your block (where'd you get it, etc)

Sounds like an over the counter race block. You should be good to go. Probably even better than a stock hemi was.

It would be really cool if you checked the cylinder wall thicknesses and posted them. I'd like to know what the QC was like on the factory race stuff. Back in the day an ultrasonic thickness checker was aerospace only and maybe not available at all. Plus it would be to your own advantage to find out the info for future use.

Thanks,
R.

Sounds fun!

What heads are you going to use?

The thinnest place is .347

Bought here of moparts back in March

I just found a set of Brewer heads that are supposed to flow over 420 Cfm
Going to pick one of them up tomorrow to get it to a known flow bench on Saturday to see what they really do, will also pressure test them before I buy. Anybody know where there is a cast brewer intake?

Is the bore really 4.25" in this block? If the thickness numbers are added for example between cylinder 4 and 6 total distance between those cylinders are 2 x 4.25/2 + 0.398 + 0.422 + water area = 5.07 " + water. But bore center distance on a Chrysler RB block is just 4.80".

Either I misinterprit the numbers or there is a measurement failure.

I'm just going to say I'd pass on the Brewers. Call T&D or Jesel and talk to them BEFORE you buy. I have offered to flow a Brewer for FREE on a FLOW DATA bench and can't get any takers. I've only seen pictures but my guess is that B-1 MC's will kick the crap out of Brewers for HP.

I've been going to the races for years now and I have never seen a set of Brewers run. Probably because I'm on the left coast. But if they were all that you'd think someone out here would do it.

In fact, I called T&D about 18 months ago on this very topic. The guy I talked to said he hasn't sold any Brewer rockers since he has worked there (IIRC almost 20 years).

Again: BUYER BEWARE.

I'm just going to say I'd pass on the Brewers. Call T&D or Jesel and talk to them BEFORE you buy. I have offered to flow a Brewer for FREE on a FLOW DATA bench and can't get any takers. I've only seen pictures but my guess is that B-1 MC's will kick the crap out of Brewers for HP.

I've been going to the races for years now and I have never seen a set of Brewers run. Probably because I'm on the left coast. But if they were all that you'd think someone out here would do it.

In fact, I called T&D about 18 months ago on this very topic. The guy I talked to said he hasn't sold any Brewer rockers since he has worked there (IIRC almost 20 years).

Again: BUYER BEWARE. [/quote]

That's why I just picked one up to check it out, pressure test and to flow it, these have a set of t&d 1.7 rockers with them so we will see but defiantly being careful, I am curious about them myself. If I get ahold of these may send one to you to flow and put it out there what they do.

That's why I just picked one up to check it out, pressure test and to flow it, these have a set of t&d 1.7 rockers with them so we will see but defiantly being careful, I am curious about them myself. If I get ahold of these may send one to you to flow and put it out there what they do. [/quote]

I'd love to do it and I'd post the results and what I think.

The other issue is while they are out there, if you beat one up, it's difficult to find a replacement. Same thing goes for valve gear. I know T&D had some on the shelf (not sure on the ratio) but you'd pay big time for them to make one set of something.

got the brewer heads flowed, they flowed 426 on a local bench. as far as rockers, I got the t&d 1.7 rockers with the heads. but still called t&d and they still sell the rocker set up for a hair over $1600. still wondering about the block, was considering going indy max low deck block, so I could use my existing tti step headers, and help on hood clearance. but they are expensive!! a new set of headers with this block would be cheaper, but still wonder about the strength of this block?

I had some Brewers. They were pretty neat. They had center bolt and o ring valve covers. They flowed 430ish with great air speed. I had a cast 4 barrel manifold. I think they only made half the amount of manifold to sets of heads due to people running sheet metal intakes. The biggest issue was valve weight with the long stems. I would recommend TI valves to help save springs.