Any thoughts about the pros and cons of running a partial hardblock engine - high HP - on the street? If the engine temp seems to run cool on the street are there any other concerns? Can a partial harblock eventually break down and get in the cooling system? Is the purpose to allow faster warm up for racing - or is it block strength adder? Assuming temps seem to run normal on short cruises could you drive a engine with partial hardblock on say the Hot Rod power tour??? Engine builders like Trishield, TA, and PAE - are they using it???
Most use the brand "Hard Blok" to fill (or partially fill) the engine block water/cooling jacket. So yes, the block on a partially filled engine would be "dry" in those areas containing the filler...
It's used to help keep the bottom end from moving around (more rigid). The oil loses heat to the cooling system in this area so there will be some loss of this heat transfer. Some people don't have a problem in this area, but I have heard of it causing bearing problems (because of the oil too hot) Running an oil temp gauge would let you know what's going on before a real problem developed, and an oil cooler would fix the problem.
Thanks Alan, I did do a search on this site and did learn more info - but still several of my original Q's are unasnwered. I have interest in a motor for sale - and it has some amount of Hard Blok (or some other filler) - and want to be well informed before I ask the seller questions. I now understand the improved strength issue, and possible HOT oil. Just looking for more feedback - pro and cons - from what others have heard or learned on there own. Again my application would be a street application (with a occational dyno and/or 1/4 mile blast) and want to be able to drive a long haul like the HR power tour.
No more chance of this than concrete disintegrating, LESS actually! You will need oil cooler with thermostat AND a very good cooling system. Of course you are going to WANT oil temp and coolant gages to monitor... If you didn't have ANY problems keeping your eng cool under ANY circumstances before, I think filling the block PARTIALLY is OK IMHO, as long as these precautions are done. (No, I don't have any real world experience doing this. This is only what I've heard! But, because of my block being sleeved and the sleeve exposed in the crankcase, I will be doing just this!!) Jeff
I've had no problem so far and my oil is not getting hot. Aluminum Stefs 8 qt pan seems to help keep the temp down. Now I wouldn't want to get stuck in a backup in 90 + deg heat though!!! Bruce
Thanks all , this is the info I need. Does anyone know if PAE, TA, or Trishield use Hard Blok - or some other "flavor'?
In the past, Jim has said he wouldn't fill a street engine more than 2" from the bottom. Mine is to the top of the soft plugs, and the oil builds up temperature. It definitely isn't something you'd want to drive on the highway! If you just want an occasional putt around town, than that would probably be OK. As BQUICK said, not traffic in 90 degree heat either. Hard Block is the stuff to use. It's available from Summit, Jegs, etc. Some of the other brands give not so good results I'm told.
