2.5 TBI vs 2.5 TI

[nvysion]

There is a voyager 2.5L TBI engine for sale à a low price.

I would like to know the difference between a CB 2.5 TI and a 1993 2.5L TBI (voyager).
I assume :
- oil return,
- pistons,
- rods,
- exhaust valves.

Is the crankshaft the same ?
Is the block the same ?
Is the block crossdrilled (93 should be, but not sure) ?

If I swap the pistons and rods, should it be equivalent to a TI

The trans should be a A523, is it useable with a turbo engine ?

thanks

[135sohc]

Pretty much everything you listed is the difference. The camshaft and valve springs are also slightly different.

Crossdrilled is a touchy subject, some do and some dont have it.

[masterjr33]

the transmission would be okay for stock/mild boost.

[nvysion]

OK thanks

[Ondonti]

the transmission would be okay for stock/mild boost.

It's good for as much as any other with the proper differential.

[83scamp]

It's good for as much as any other with the proper differential.

+1. I'm putting an A-520 with an OBX behind the 2.5 I'm building, and I'm going for about 300 hp with my build.

I forget where I read it, but a 520/523 is within about 10-15% of a 555/568 as far as a hp/tq holding ability. The difference isn't as great as a lot of folks want you to think...

[OmniLuvr]

I think the newer blocks are better (heard 92 and up all had higher nickel content when made in mexico, some of the earlier blocks did too).

also the "91" and up 523 trans is strong, the date stamped "90" 523 trans is the week one, it had finer cut teeth on the gears and tends to strip the teeth on third gear over 275ish hp. also, there is different final drive ratio trans on the 523 and some also had different gear ratios (although only a very small difference). I believe the 93 and 94 523 trans had a 3.70 something final drive, which I like because its kind of a happy medium between the 3.50 and 3.86 (?).

also, the 523 has the ability to remove the "differential" so it can be swapped with a lsd unit.

low boost mild build any 523 should be fine, but I had problems over 21 psi with the early 523 in both my charger and my Omni...

[2.216VTurbo]

In my experience By 93 all the exhaust valves were the same content, early turbo valve were different and had a "T" cast into the head of the valve. I agree that the 523 is plenty stout, I prefer them for shift quality over 568's actually.

[135sohc]

I think the newer blocks are better (heard 92 and up all had higher nickel content when made in mexico, some of the earlier blocks did too).

also the "91" and up 523 trans is strong, the date stamped "90" 523 trans is the week one, it had finer cut teeth on the gears and tends to strip the teeth on third gear over 275ish hp. also, there is different final drive ratio trans on the 523 and some also had different gear ratios (although only a very small difference). I believe the 93 and 94 523 trans had a 3.70 something final drive, which I like because its kind of a happy medium between the 3.50 and 3.86 (?).

also, the 523 has the ability to remove the "differential" so it can be swapped with a lsd unit.

low boost mild build any 523 should be fine, but I had problems over 21 psi with the early 523 in both my charger and my Omni...

3.77 final drive, they came out for the 92 model year.

[nvysion]

I bought the engine with trans, in the bottom it is stamped 93, does that mean it was made in 93 ?

Also, the coil is located near the thermostat housing, can I use it instead of my 89 coil (filled with oil) or the wiring/electronics are different animals ?

[enduro74]

I bought the engine with trans, in the bottom it is stamped 93, does that mean it was made in 93 ?

Also, the coil is located near the thermostat housing, can I use it instead of my 89 coil (filled with oil) or the wiring/electronics are different animals ?

The date is cast into the back passenger side of the engine block. May be stamped other places as well. I have been able to change from the canister coil to the newer style that is mounted on the thermostat you just have to have the connector to splice in the wires. Also you will want to get a newer style ignition coil to distributor wire as the old style one is left exposed if you use it on the newer coil.

Also to answer your question about cross drilling I have yet to see a 91+ TBI engine that was not cross drilled. There could be one out there that isn't but I have yet to see it and I have had a LOT of TBI engines apart. Both 2.2 and 2.5

[Dr. Johny Dodge]

when comparing the 89 cb and 93 cb blocks I have the 93 is a much nicer casting

where the 89 has many rough spots the 93 is nice and smooth
also the bar cast into the back of the blocks is much nicer on the 93 block
the 89's is concave , inwards towards the block when viewed from above
the 93 has a much flater and more even shape to it and has metal the 89 is missing due to the curve in it

overall casting of the 93 block is much much nicer than the 89

also I've read but haven't yet confirmed (by pulling my short blocks apart) - the 92/3 blocks are suposedly thicker at the main webs for the crank journals than the earlier common block castings