How much hp can an stock apex block take?

[jhlarsen]

where do we see the problems starting?
and where is the weakest link?

i'm thinking beside the rods, stock pistons and headstuds.
where is the point the sylinders starting to get oval?

 

[Simons CPR]

stock blocks are good for high 300 hp levels with low compression, to go into 400 hp and beyond i recommend our superman block modifications which are are good for 550 plus hp, carrillo rods, our hd 12 mm studs and low compression pistons. you can use our 10 mm hd studs for levels below 500 hp. for more info and prices you can talk directly with me at 1-414-698-6611 jeff simon / simons cpr

 

[rxrider]

I have seen high 400s on stock block dynoed at MCXpress in Sweden. I would not thrust the logevity of a stock engine (lowered compression) running that much HP. At 400 HP the MCX turboed Apex'es seems to hold up as far as I can tell, lowered compression tho. I agree with Simons CPR, I know I'm pushing my luck at 350 HP on my RX-1 at 10:1 CR and 22 lbs of boost.

 

[mulot30th]

I have seen high 400s on stock block dynoed at MCXpress in Sweden. I would not thrust the logevity of a stock engine (lowered compression) running that much HP. At 400 HP the MCX turboed Apex'es seems to hold up as far as I can tell, lowered compression tho. I agree with Simons CPR, I know I'm pushing my luck at 350 HP on my RX-1 at 10:1 CR and 22 lbs of boost.

AT what elevation?




350 CORRECTED hp at 5000ft.... is not the same stress on block as 350 corrected hp at sea level.


If this is ACTUAL hp then.... I would never I though the stock block could handle 400hp

 

[rxrider]

Hi buddy - I'm at sealevel, I actually ride on the frozen arctic ocean in cold dry air. I'm aware of altitude and it's impact on power output due the reduced amout of O2 in the air at 5000ft.

These sleds were dynoed on a Superflow 901 at MCXpress in Sweden, MCX are close to sealevel as well. MCX does not use a correction factor on their dyno. The 500HP sled is was a race sled, the 400HP sled is my friends trail unlimited sled.

Myself I would not run those sleds with the stock block, as I said I feel I'm stretching it running my old RX-1 at 22 lbs and 350+HP on a stock block

 

[mulot30th]

d e dd

 

[mulot30th]

For example... a radar sled at 400hp actual hp stock block might ... have a problem holding wideopen for like 2000 ft?


drag racing... like 4-5 seconds wideopen... not so much big deal...

 

[jhlarsen]

enyone inspected a block that have run high hp levels for a sesson?
does the cylinders get oval? where does the block fail?

 

[rxrider]

d e dd

I'm not familiar with that word

 

[rxrider]

oval it gets, haven't seen a cracked block as of yet. Head gasket tend to fail because the cylinder tower moves around in the water jacket causing the head gasket to fail, been there done that due to wrong torking procedure.

 

[jhlarsen]

oval it gets, haven't seen a cracked block as of yet. Head gasket tend to fail because the cylinder tower moves around in the water jacket causing the head gasket to fail, been there done that due to wrong torking procedure.

well, thats a human failure :-D

 

[rxrider]

It was, it's a long time ago LOL, now I have ARP studs torked at 2X what I had back then.

 

[HURRICANE]

We have seen broken blocks,oval cylinders,burned out headgaskets and all kind of other failures that have led the way to the development of the Hurricane Block.Although nothing is indestructable but we are now capable of containing over 600hp

 

[mulot30th]

I purchased a rx1 that was run 2 seasons of racing with 21# of boost, the block was stock rx1, and it was egg shaped on all 4 cylinders and a bit of taper on top too.

engine was still running pretty good, but was not in good shape.

 

[rx1turbo]

Last year i ran my rx-1 up to 24 psi for a weekend of drag racing. BIG MISTAKE the stock block won't handle it. Could actually see the egg shape in three cylinders. My block is at hurricane performance as we speak don't take any chances