hprsepower limit of 392

[wud73]

Working to get a hemi in my old battlewagon. 

USE - Bracket type, oldy racing.


CAR - 1960's altered, hardtail, 125".  Using  powerglide.
       - Most the cars in the club have about 700 hp.

I need the engine to be as dependable as possible  (I just don't  have the time or money to blow up even one hemi)

ENGINE STUFF I HAVE -

      - .060 392
      - Couple good std. cranks
      - HotHeads aluminum heads
      - Good blown alchohol roller cam
      - vertex
      - 6-71  non-stripped
      - Bugcatcher

SO HERE'S MY QUESTIONS:

1- What's the horsepower limit of a 392 w/ 4bolt caps and stock crank?  By that I mean what's the limit where it is still very dependable?


2- To produce 700 hp do I need to concern myself with a stroker crank  or fancy blower?  (although an offset grind w/ Chevy rods is easiy enough).

3-It seems every hemi guy I've ever talked to says that race engines must have aluiminum rods.  Go to a doorslammer site and they make a lot of power on steel rods.   At 700 horsepower is there any reson I can't use the K1 steel rods?  What about even Eagles? 

4-If aluminum really soaks up shock then what about alumimum main caps and steel rods?  Do you even get that much shock and vibration in an engine that's not nitro?

I know that's alot but I appreciate the help. 

[LZ]

Wud:
In case you had not seen it . Dan Miller (rip) wrote out some notes from Gene Adams. Some good reference here.
http://www.thehemi.com/forums/viewtopic.php?f=3&t=2851

Matt will get back to you with sensible - reliable info, just give him a chance , busy.

Doing up an early hemi myself. Well...... I have parts and plans.  Wanking it right now....
Its OK to sign your name were all friends here....
Luke

[wud73]

Thanks Luke,

I've just about got the Gene Adams article memorized.  I just don't want to pass on the opportunity to tap into experience made easy thanks to the internet...I hate it and love the web.

Wayne

[MaggiFinn]

We race two engines, allthough SBC, I would think the same applies to connecting rods. Both engines ingest more nitrous than most care to think of when using stock blocks and cranks. The small one (355) has more power ~70hp but uses less bearings on both rods and mains. It has aluminum rods. There is some minor cap walk on both engines though at this power level and we have broken the no1 main cap but without hurting bearings on the alu rod engine. The engine seems way happier with aluminum rods, than without.


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[wud73]

Thanks for the reply....any idea how much power your making and at what rpm?  Do you have a heavy piston?

[Frontenginedragsters]

700HP should be no problem as long as the blower makes enough pressure without strips.
Run some feeler gauges in it and see how loose it is.
I think aluminum rods are the only way to go with what your trying to do.
Just put in NEW and not used ones. We use Venolia.
The factory steel crankshaft will handle 700HP without problems.
Thats what I think
Matt

[Paul New]

I bought 3 392's planning to install them in my FED. I talked to Gene Adams and what he told me is run injected nitro to run the 6.70's that I was running with my blown alky SBC. With a blown alky and the 392 7.0's is all he recommended otherwise you will rip the main webbing out.

[wud73]

I got a couple replies in the general dragster section, here and a PM as well,  thank you everyone.

Sounds like reliability won't be a problem running 8.50's / 700 hp. 

Let me ask this question about Mickey Thompson rods............WAIT!!  I know that old souvenir rods are paperweights...but .this is a different story here.

I have 16, honest-to-goodness- brand -new, uninstalled MT rods.  If they were once good for 1000 hp and the pounding of nitro  .........any reason why they wouldn't be OK for a 700hp, low boost alky engine today?

I spoke to a guy who was in on the design of those rods with MT.  He said that two sets would last a "romperroom" low-power program (like mine) a long, long time.  A friend told me that ARP even catalogs a bolt for the MT's  (and he suggested a modern bolt).


Uhhhm...does that make any sense?