175 vs. 200 (both 2.5)

[spanky2002]

is there any difference in the ports on these two merc motors?

[O/B Dude]

I've never owned a 175 but its my understanding that both are the same except for the exhaust passage size into the exhaust adaptor and possibly carb and tuner are different. Usually 175's are detuned 200's, with identical porting.

[Jay Smith]

Have a relief slot approx. 1/4" wide and 1/2" long above the exhaust port , this is to make the motor idle smoother.
These blocks are less desirable to hot rod than the ones without the idle slot..........

[spanky2002]

not looking to hot rod any of these motors. i am thinking about running superstock at dsra this up coming season and 200 hp (10 pedal) is the most allowed. i may have my hands on a 175 for a good price but didn't want to buy until verifying the difference (if any) on the ports.

[Dave S]

Some where I think around 1996-7 the difference between the 175 and 200 was the 175 had the exhaust slots and smaller runners in the chest. Before that, the blocks looked the same. Jay is rite about the slots, so try to get the rite block. You can hog out ports but you can't get rid of the slots easyly.

[T-REX]

If U gunna run SS in DSRA, find a 200 2.5 block and match'in front!!!....They will allow NO grinding in tha blocks other than matching a replaced sleeve, and it haz to be stock specs...

Tha slots will not be good for a competitor in SS...It won't meen much ov a loss, but in SS, it will be so close, tha slots will be juss enuff for U to sukk hind tit!!...If U gunna buy a block(new or used) for SS, find tha late model wit tha pro max exhause chest!!...and also find tha 38cc heads, and don't cut no 42's to 38's...stay wit uncut heads....They are plenty 38cc's out ther, use them!!...If U show up wit cut heads, even if tha cc's are close, U will be DQ'ed...

If your like me, and I had a 175 block, I would try to make it competitive, juss kuzz it's tha way I am...BUT, in all honesty, that mota wit tha ex reliefz, won't reely be competitive...U won't git 1/2 tracked!!!...But, I don't thank it will make U a front runner either...

Git sumpth'in goin...SS in DSRA this kumm'in yeer will be a big and a close race'in class...MORE FUN fer tha buck fer sho!!!...I'll be ther, LORD say tha same, but I gotta run them lil junk small CI mota's...UNLESS I WIN THA LOTTERY!!!!...REX:cool: