Comparing '96 150 Faststrike to a 175 Faststrike

[Jon in TN]

I've heard the only difference is the carbs and everything interchanges. True or False?

Thanks!

[rudetech1]

False. There is a small DIFFERENCE in the PORT SIZE and LOCATION of the ports in the cylinder walls. All the parts will bolt up,all the machining is the same except for those small details. To build more horsepower, you have to be able to dump more exhaust and pull in fuel a little quicker on the up stroke.When you look up the part numbers in a parts book, the numbers are different. There is ALWAYS some kind of difference when the part numbers are NOT the same.There are usually tuning differences on the 2 lower cylinders on 60 degree engines. Typically these cylinders have a LITTLE lower compression.

[Jon in TN]

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rudetech1 &raquo;</TD></TR><TR><TD CLASS="quote">False. There is a small DIFFERENCE in the PORT SIZE and LOCATION of the ports in the cylinder walls. All the parts will bolt up,all the machining is the same except for those small details. To build more horsepower, you have to be able to dump more exhaust and pull in fuel a little quicker on the up stroke.When you look up the part numbers in a parts book, the numbers are different. There is ALWAYS some kind of difference when the part numbers are NOT the same.There are usually tuning differences on the 2 lower cylinders on 60 degree engines. Typically these cylinders have a LITTLE lower compression. </TD></TR></TABLE>

So if I bolted a set of 175 carbs on the 150, it wouldn't give me extra HP? Would it even run right?

The reason I ask is, I've been offered a blown top end for parts, but I don't want it if the parts won't interchange... Although all the ignition/electrical stuff should be exactly the same. Right?

[ChampioNman]

Steve,
You forgot the red switch under the flywheel.

[Lockjaw]

There are a couple differences. The port height on the exhaust port is higher by a small amount on a 150 over a 175. The main jets are usaually one size larger as well.

changing the carbs won't have any effect really they are the same size.

If you want some extra performance, get some Ficht 150 rubber reed cages and put them in your engine. Also convert over to XD100.

150's make peak power about 5400, 175's make it at 5700. Mine will hit the limiter with my tempest. Sure sounds good spinning up there.

I am going to try an early 91 series head and see if it helps. And will likely plug the idle reliefs too.

[Kris481VS]

Is it hard replacing with those Reed Cages?
Kris

[ChampioNman]

It would be wise to get a shop manual and not a Sealoc type. Carbs and intakes have to come off to replace the reeds.

[Lockjaw]

No its not hard, I could probably replace them in less then an hour now. You need to be careful with the little black balance tubes though. get in a hurry and you are likely to break one. Make sure you have red loctite too.

Also in my other post, the 175 has the higher port height on the exhaust, tI think I had it reversed.

The lower compression on the bottom 2 cylinders was in corporated into all the 60 degree engines, and 96 150's should have it. Mine does.

It is generally accepted the 150's have more bottom end grunt. Not sure how much. I would love to find a 175 PH and swap mine out and see what the difference is.