Need help with a chevy B/B motor ID

[IH2LOSE]

On the area above the water pump it say "TI202TST" any body have an idea of what this block is.

I cant get to the side of the block or to read the rear casting number now.

As always any help is apreceated

 

[midyear]

Larry,

Looks to be a 78 chevy truck 250hp 454.

Dennis

 

[IH2LOSE]

Thanks Dennis

I have a performance LS6 crate motor I had planned on installing in the car,the motor builder is suggesting the motor as it is,may be too strong for what i want for the car.(so you might be thinking why would a motor builder suggest a crate motor,because I have been doing buisness with him since I was a kid and he explained I am always looking to have work done every 2 to 3 years and he will rebuild a motor for me then he is just trying to do whats right for me)

So in order to use this motor he would detune it,Lower the compression,put in a hydralic roller cam,anyways we are taking about 3 to 4 grand. at that point I mine as well put in the 454ho crate motor, the above motor I was asking about is available for me after it had a stock refreshing about 20,000 miles ago, the fellow who owns it has it in a plow truck and he was told it was out of a 70 ambulance.

could you please explain to me what retancular port heads are and the oval port heads How do I know the difference?

the 454ho seems like a perfect motor.LOW COMPRESION

 

[67HEAVEN]

Larry,

The rectangular port heads were found on the high horsepower, solid-lifter big blocks; the oval ports on the mid and low horsepower engines.

The above applies to the late '60s and early '70s. In the aftermarket world, you can get most any configuration you want.

 

[bossvette]

there were/are actually three castings for the BB . The rect port are the High performance and have large rectangular intake ports valves, runners etc are bigger; the oval port head has oval shaped intake ports and is more desireable for street use the third type or round port has smaller round intake ports and smaller valves it was used on low HP versions of the BB trucks motorhomes etc

FWIW they were still casting all three versions in the mid 90's when I worked on the head line in Defiance there is a large difference in port size.

 

[IH2LOSE]

Thanks guy

 

[vette]

Larry. I have a 454 LS6 crate motor in my 65 chevy Biscayne. It was bought before GM changed to roller cams. Before I installed the motor I changed the cam to a soild lifter set up.The intake is an Offy crossram. The car has a richmond 4+1 trans and a 356 12 bolt. It pulls like a bear. It ran low 13's at the track. All stock suspension. And this car is 4000 lbs. The 454 crate they sell today has a roller cam that works very well. The open chamber rect. port heads are much better flowing than oval port. And with the flat top pistons they use you get a low comp.motor. The only thing I would think about is maybe buying just the short block then going with an aftermarket alum. head. The steel heads are super heavy. The weight alone is worth going to alum. If I needed to buy another big block I would buy the 454 HO.