Competition help with piston choice

[Hendricks]

I have finally gotten the 4bt tore down and the block and head will be off to the machine shop soon. I am going to have to bore out the cylinders(around 1mm acording to what is available from cummins)but I am not sure as to the diffrences between piston types. The pistons that came out of this engine have a much smaller bowl and it is offset toward the injectors in comparison to my 24v. Are these industrial pistons? My all out goal is to ring 300 ponies from this little brick and I want to make sure that i start with building the bottom end correctly from the start. The inline pump is also going to be on its way to Industrial injection soon to be laid in their capable hands. This is my first perfomance build so any help is more than welcome. By the way anyone know who can build me a performance cam for a 4b

 

[BILLVO]

I know a lot of guys running the new CR pistons in the 24valve engines with good luck it really cleans them up and quiets them down a bit also. they have a larger bowl in them which is better for a lot of the bigger injectors out there now that have a broader spray pattern than the stock sticks.

 

[catoiler]

Billvo,I think he might have a hard time getting those pistons in "I have finally gotten the 4bt tore down".

 

[Hendricks]

ok after finding some other pics on the net, these are the same pistons as the 94 to 98 12vs i belive. So are there any other options i should consider, benefits to aftermarket setups or should i just go with the cummins overbore pistons. Also any aftermarket rings that are performing better in high egt applications.

 

[BILLVO]

Billvo,I think he might have a hard time getting those pistons in "I have finally gotten the 4bt tore down".

A 4bt is same engine just short 2 holes.

Do the 24 valves have a different bore size than the 12 valvers I believe that a local engine builder is running the CR pistons in both 12v and 24v but not 100% on that. I know he puts them in all 24ver's he rebuilds.

 

[DPS]

boer size and spacing is the same on all the B series, isb, isbe. The best piston to use is the cummins industrial, or aftermarket reproduction. My reasoning is the ring lands are set so you can have plenty of valve relief cut into the piston and not get the margin too thin and risk burning rings.



Josh

 

[JoshPeters]

I'd give Haisley Machine a call. They will be able to advise you on the piston choice, machine them if nessissary, and probably even regrind the stock cam for you.



JP

 

[dieselcruiserhead]

anyone have a link for CR pistons out of curiosity...

 

[catoiler]

A 4bt is same engine just short 2 holes.

Do the 24 valves have a different bore size than the 12 valvers I believe that a local engine builder is running the CR pistons in both 12v and 24v but not 100% on that. I know he puts them in all 24ver's he rebuilds.

Damn thought they were smaller!guess ya learn something new everyday!

 

[Timebomb]

As for the cam, you can look up Camcraft in Elkton MD. They are the source for alot of the performance cams for our 5. 9s