Any tips? I have a 170 slant with 95k that I'm looking to change to a 225 in a '64 valiant. Any gotchas I need to be on the look out for?

There are crankshaft differences between early and later engines.

My memory is 1969 and later used a larger crankshaft hub. This comes into play for car with automatic transmissions, to fit the early torque convertor into a later crankshaft an adapter/spacer is needed. It is well documented on this forum.

Engines that came with an auto may or may not be drilled to accept a pilot bushing for the end of the transmission. Honestly I don't recall if early and later manual transmission flywheels interchange.

Is there anything actually wrong with the 170? It is a solid and reliable engine, maybe more so than the 225. If you want more power 225 has some advantage and some disadvantages due to how they rev. For a cruise car the 170 should be able to function quite nicely in a 64 valiant.

edit....

Also sometimes people on marketplace don't actually know what they are selling. A few years ago I picked up a slant that just listed as slant six. It was a 170 out of a 63 valiant. I bought it for a potential future high rev build. On marketplace right now in IL is slant listed as coming out of 1978 d100. It isn't from a 78, it is an early 3 core plug block which means it is a 60's era unit, it is red and all the pieces are consistent with 60s instead of late 70s.

Nothing wrong with it as far as I know but it hasn't run in a few years now (garage kept and not running due to cracked exhaust manifold and carb issues). I'm looking at possibly going for a torqstorm SC build and from my somewhat limited researched it seemed like I would see better results from the 225. Would love some more thoughts on this.

Do you have a dollar amount/limit? The search for horsepower can get quite spendy fast.

The cracked exhaust was very common especially on the early manifolds, almost always right behind the cylinder 3 runner. There some good and terrible replacements available, there is a thread on it here somewhere.

What is your intended usage of the car. The torquestorm has good review but requires work and tuning to get it right.

End goal for the car is a car show/weekend cruiser. Nothing crazy but something that is worth showing and looks/sounds good. My thought with the torqstorm is it would allow me to add some power to the slant and have a unique show piece. Slants are already less common than a dropped in 360 but a SCed one would likely be even more rare. Hadn't really put a finally dollar amount on the project yet, obviously the torqstorm kit is like $3800 by itself. I know there will be plenty of other items that need to be changed to accommodate the boost and torque. I'm okay toying around with the tuning a bit but don't want to be on the complete edge of usability with it constantly having to be tweaked to get it running right.

If you want the V8 dual exhaust sound a slant will never achieve it.

Some people like the sound of an inline six. Personally, I think they sound best with a large single exhaust with a turbocharger chopping the exhaust pulse. One of my coworkers keeps bringing me his MKIV Supra when he needs stuff fixed and it shows how good an inline six can sound, but his car has 500ish hp and twin turbos through a 4 inch sewer pipe sized exhaust so not the most fair comparison.

Agreed. I've heard the slant and I think it has a great sound. My daily is a turboed straight 6 so I have a great appreciation for the platform.

'68.
Agree

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