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skauto
02-21-2010, 05:45 PM
I have a 572 bbc with a callies crank carillo rods, 9.5:1 compression it was a blown gas hydro boat motor and i want to convert it to alcohol and run a 1471 with low boost 20psi max, can i safely stay with the steel rods or should i go to aluminum? i am trying to run a mild combo in a 2600 lb door car to run 7.50's any thoughts on this set up would be good
Thanks

markdunlap
02-21-2010, 06:05 PM
Aluminum rods are better for any blown engine as far as acting like a cushion for the crank and rod bearings. Keep in mind if you change from steel rods to aluminum the bob weight will be different and the crank will have to lose alot of weight.

zipper06
02-21-2010, 07:43 PM
X2 on the alum. rods, alcohol is a lot harder on the bearings, and i imagine running a blown gas motor he wasn't putting any where near 20 lbs. boost to the motor.

JMO

Zip.

skauto
02-21-2010, 08:13 PM
the blown gas hydro motors are running up to 1400 hp and as high as 8400 rpm for extended runs at 12-18 lbs boost. so i just am curious why steel rods wouldn't work for a similar power range on alcohol i fully understand why you aluminum rods are recommended but if a person watched the con rod bearings and ran a conservative tume up why not run steel rods?

kwkracing
02-21-2010, 09:50 PM
Why would alcohol be hard on bearings? Except for deluting the oil and loosing lubrication? Where not talking about mixing nitro? I have never had a problem running alcohol with engines or fuel lines.

Yes if you have a serious set of steel rods u can run them. Just remember parts dont last forever and if they have been turned up like that in the boat, Its probably time to change them.

What size blower was on the 572 before?

Remember, your gonna make more power going blown alcohol than gas.

zipper06
02-21-2010, 11:35 PM
I'm not saying you can't do it, but alum rods are better. In fact i have a 1471 with a buzzard catcher blown 358" chevy. It ran o'k until i melted down a piston due to no port nozzles. Shown below in vid. (Smoke is from a leaking valve cover). It went 4.62 running 20% overdrive, about 35 lbs. boost on alcohol, before burning a piston. I put it in my friends ugly Dodge Dart as seen in the vid. i'm behind the camera.
It's going back together as a 383" with alum rods, and going into my 48 Anglia.

Zip.

turn sound up.
http://video.google.com/videoplay?docid=3005024568453485455#

hammertime
02-22-2010, 04:52 AM
Why would alcohol be hard on bearings? Except for deluting the oil and loosing lubrication?


Your are correct ..

skauto
02-22-2010, 06:25 AM
Again only from what i understand is alcohol is more of a violent explosion than that of gas (faster burn) so with high compression and boost it loads the top rod bearing harder. But i gues if you run a similar combo as that of gas it really shouldn't be harder on the bearing? The hydro motor ran an 871

kwkracing
02-22-2010, 07:39 AM
if you put a dab of gas on the ground and throw a match.
if you put a dab of alcohol on the ground and throw a match.

The one that is more explosive is th one with the lower octane.

Alcohol is better, it keeps parts nice and cool not to mention other things i know nothing about.

Dont put a dab of nitro on the ground, you may end up with a giant crater in the ground.

I agree Zip,All my blown engines have aluminum rods and they are some gernade pinned pulled shock absorbers that help cushion the impact we pust our engines.

zipper06
02-22-2010, 12:58 PM
There's no question about it carillo's are good rods, they were the first to introduce H beams, carillo's and Lenz are the premium of the steel rod field, atleast NASCAR thinks so. If you are going to stick with them i would have them xrayed, and put new L19 bolts in them since they have been run already and you really don't know how hard.

JMO

Zip.

skauto
02-22-2010, 04:31 PM
Sorry the parts are all new the short block was built for a blown gas hydro but never used.I picked up freshly assembled by machine shop.

zipper06
02-22-2010, 08:30 PM
Sorry the parts are all new the short block was built for a blown gas hydro but never used.I picked up freshly assembled by machine shop.

8) Good too go then.

Zip.

skauto
02-22-2010, 09:50 PM
thanks for your input i'll give it a go and keep you posted as to how it works out