gonna use the 90 tbi CB

[Realest]

gentlemen!
can someone fill me in on what i am gonna have to do to the bottom end.
i tossed a rod throught the pan clipping the edge of the block on the way down and breaking it in my '88 TI engine in 90 daytona ES (orginally 2.5 NA). i want to take the 2.5 NA CB block and turn it into a turbo engine. I am unclear of the internals i am gonna have to use. My understanding it that the cranks stroke is the main difference in achieving the .3 Liters.
So with that in mind i have two directions i can go
-retain the stock 2.2 computer forcing me to rebuild the bottom end completely
or
-find myself a 2.5 calibration, keep the crank, change out rods and pistons and go to town.

The second of the two options seems like the better choice....I don't need to worry about machine the block because i had the 2.5NA rebuild before it changed over to a turbo. The engine was presurizing back in the day and rather than get a new head i opted for the turbo engine out a parts shadow i had.

Please give me your opinion and let me know if i am missing something.

Thanks
Ryan

can i modify fuel delivery and keep the 2.2 cal?

[kermit]

don't forget that the CB 2.5 had different pistons than the CB 2.2

[ZoskalonMPI]

All CB rods are the same size and TI and TII CB rods are the same forged rods. If you're going 2.5L, the TBI crank is the same as the 2.5L TI crank. Pistons needs to be from a 2.5L TI.

So if you want turbo, find any CB turbo rods, use stock crank if good, and either get good used 2.5L turbo pistons or buy new ones. This is good up to 300HP as people say, the TI pistons are the limiting factor.

Also, you need to either remove the plug in the back of the block and tap it or drill a hole in the oil pan for the oil return line. And also add the extra oil and coolant supply lines.

Or you can get a 2.2L crank and stick it in the 2.5L TBI block. Not sure if you can use the nonCB 2.2L turbo pistons you have though, someone else can clear that up. If you're going to get new rods and pistons, you mind as well get the crank as well and make it all 2.2L and not deal with the cal.

[Paradox]

2.5 pistons are different from the 2.2. The only thing that needs to be changed if I recall is the pistons and the valves

[Realest]

i believe the the 90 tbi cb rods are light with....could work but don't want to use weak rods. pistons yes will be changed just have to measure the holes and see what they are bored over from the engine job. the valves i don't have to worry unless i can't use the 88' turbo head on the 90 CB.
i think finding a good used 2.5 computer will be cheaper then changing cranks....so i'd like to go that route.

[ZoskalonMPI]

You can use the turbo head, same head as the TBI but with stronger exhaust valves.

[1983Rampage]

I was wondering, what size of hole needs to be drilled in the pan for the return line? Thanks, Matt

[Realest]

http://www.turbododge.com/forums/f4/...ing-turbo.html

1983RAMPAGE read this thread...Blue Iroc R/T explain it really well. You drill the block not the oil pan!

[1983Rampage]

thanks, that had everything I needed.