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Discussion Starter #1
Hello guys, new member and new to Valiants.

Hoping you can help me put together a list of parts and where to get them for a ground up mild performance rebuild on my 67 225 slant 6.

From what I can see , parts, especially new flat top pistons are hard to come by? I'm guessing I need .030 or .040 over size (have not pulled the motor yet). Con rods, new push rods, lifters, camshaft, all bolts, balancer, gasket, rear seal, water pump and oil pump. intake manifold (aussie speed) and exhaust manifolds.

I've seen some rebuild kits online, but unsure and thinking I might be better off piecing it together myself?

Any advice welcome.
Thanks.
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Hello, and welcome! By "mild performance", what did you have in mind? Early '60's Slants had optional Hyper Pack 4-bbl intakes, and I saw a '64 Dart at a Mopar show with dual single-bbl carbs. Some Slants had small BBDs in the late 1970's. Though I'm not familiar with Aussie options, I don't recall any specific performance upgrades for the '67 model year, except to 225 cubic inches from the base 170. But Slants were essentially the same throughout their run, and any performance intake that fits should work on them. If that's the direction you take, make sure the exhaust is similarly upgraded, and that the linkages work. Try to avoid aluminum intakes from the late 1970s, as they had tendencies toward cracking and warping, and the 2-piece design sometimes developed air leaks. A cast iron intake will probably last longer.

Many owners on this site recommend rockauto for quality and price:

1967 PLYMOUTH VALIANT 3.7L 225cid L6 Engine Parts | RockAuto (at https://www.rockauto.com/en/catalog/plymouth,1967,valiant,3.7l+225cid+l6,1378212,engine )

You might investigate shipping charges halfway around the world before making any decisions.
 

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Discussion Starter #3
Thanks, what brand / set of pistons would you recommend? looking for nice flat tops with valve reliefs.
Are Engitech pistons any good?
thanks
 

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I've not replaced pistons in any of my engines, so I don't have personal experience with Enginetech. Here's a thread about them:

Anyone know anything about Enginetech Pistons? - Yellow Bullet Forums (at https://www.yellowbullet.com/forum/showthread.php?t=924138 )

And a video, with some comments below:

View: https://www.youtube.com/watch?v=r2J8bo68JOE


They seem to be good quality and reliable; note that, in both cases, they were used in GM engines.
Thanks, they look they will be a good choice for a mild performance build. ..... shooting for around 9.8 comp.
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Discussion Starter #6
Thanks guys, I'll probably need my pushrods reground, right? or can you buy new ones to order?
thanks
 

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Here is a Super 6 2V set-up
super6.jpg
 

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Here is an idea of what you want to purchase and what needs to be checked prior to purchase.
Pistons, as you mentioned, will need to have the block checked to determine whether or not she needs bored, thus oversized pistons. There are three basic levels of pistons, being cast aluminum, hypertuetic(might be spelled wrong), and forged. Cast for stock applications, hyper or forged, a little and much more expensive, but not jaw-dropping expensive, hyper gives a good balance of cost and durability to heat.
Rods, unless broken or bent, can be checked and resized to make sure they are straight and true, which is much cheaper than new ones, if you can actually find them new or aftermarket, new piston end bushings installed if needed (I believe they are).
Gasket set covers all the gaskets needed for the overhaul, and would cover everything except your 4bbl carb itself, it isn't offered for the slant six (ever), which is understandable.
Oil pump, you would want high volume if possible, and if not available, break a new one down and open up the flow passages, it improves flow and volume and isn't a real ton of work, always good practice to clean up the flow on a pump anyway.
Distributor. If you have points (because it hasn't been converted to electronic at this point), plenty of aftermarket companies out there to convert at a reasonable price, Pertronics has been pretty decent about making conversions, so make sure the bushings in the distributor housing are good and the shaft doesn't wobble.
Bearings. That's up to you, but rod and main bearings are relatively inexpensive actually, should get the tri-metal bearings for durability, also go by the name Clevite 77.
Pushrods. Check them, verify they are straight, tips aren't worn out, and no, they don't get ground, they simply get replaced if worn. Now rocker arms are a little bit different story, the end of the valves can indent or over time form a wear pattern. This can be gently sanded/ground out of them to fix that issue, and if not mistaken, the rockers are both adjustable and bronze bushed and can be replaced to improve stability and rocker arm geometry.
The camshaft itself, which is where the power of the 4barrel carb gets to do its work put to the test. It is a solid lift cam, with solid lifters and adjustable rockers, but you don't want to go too radical, which would be difficult to drive on the street. So, from the specs on your stock cam, which can be looked up or profile verified with a dial indicator and degree wheel (all cam grinding companies can verify what you have and what they can do), but basically, and increase in the duration of the camshaft by 12-15 degrees and an increase in lift of .050-.075 inch over stock would wake the engine up without killing its drivability. There are several aftermarket companies that make new cams with this type of profile, they used to call them RV cams (about a step above stock, maybe a hair more). Or you may have access to a cam grinding company that can help out on this one, including refacing the lifters.
Lastly, the head. Given porting is probably out, clean everything up, make sure things like rough castings in the ports are ground with a grinding stone, or my favorite tool is a carbide burr cutter, about the size of your index finger to the first knuckle. It has a rounded end and it good to keep corners from getting too tight. We can talk porting and touching up the combustion chamber later, this is getting pretty long, but will get you headed in the right direction to get things started.
And one other thing, the "rebuild kits" that are cheap, are just that, unless they give brand names, they are designed for quick flip out the door running to an unlucky buyer.
 

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Discussion Starter #10
Here is an idea of what you want to purchase and what needs to be checked prior to purchase.
Pistons, as you mentioned, will need to have the block checked to determine whether or not she needs bored, thus oversized pistons. There are three basic levels of pistons, being cast aluminum, hypertuetic(might be spelled wrong), and forged. Cast for stock applications, hyper or forged, a little and much more expensive, but not jaw-dropping expensive, hyper gives a good balance of cost and durability to heat.
Rods, unless broken or bent, can be checked and resized to make sure they are straight and true, which is much cheaper than new ones, if you can actually find them new or aftermarket, new piston end bushings installed if needed (I believe they are).
Gasket set covers all the gaskets needed for the overhaul, and would cover everything except your 4bbl carb itself, it isn't offered for the slant six (ever), which is understandable.
Oil pump, you would want high volume if possible, and if not available, break a new one down and open up the flow passages, it improves flow and volume and isn't a real ton of work, always good practice to clean up the flow on a pump anyway.
Distributor. If you have points (because it hasn't been converted to electronic at this point), plenty of aftermarket companies out there to convert at a reasonable price, Pertronics has been pretty decent about making conversions, so make sure the bushings in the distributor housing are good and the shaft doesn't wobble.
Bearings. That's up to you, but rod and main bearings are relatively inexpensive actually, should get the tri-metal bearings for durability, also go by the name Clevite 77.
Pushrods. Check them, verify they are straight, tips aren't worn out, and no, they don't get ground, they simply get replaced if worn. Now rocker arms are a little bit different story, the end of the valves can indent or over time form a wear pattern. This can be gently sanded/ground out of them to fix that issue, and if not mistaken, the rockers are both adjustable and bronze bushed and can be replaced to improve stability and rocker arm geometry.
The camshaft itself, which is where the power of the 4barrel carb gets to do its work put to the test. It is a solid lift cam, with solid lifters and adjustable rockers, but you don't want to go too radical, which would be difficult to drive on the street. So, from the specs on your stock cam, which can be looked up or profile verified with a dial indicator and degree wheel (all cam grinding companies can verify what you have and what they can do), but basically, and increase in the duration of the camshaft by 12-15 degrees and an increase in lift of .050-.075 inch over stock would wake the engine up without killing its drivability. There are several aftermarket companies that make new cams with this type of profile, they used to call them RV cams (about a step above stock, maybe a hair more). Or you may have access to a cam grinding company that can help out on this one, including refacing the lifters.
Lastly, the head. Given porting is probably out, clean everything up, make sure things like rough castings in the ports are ground with a grinding stone, or my favorite tool is a carbide burr cutter, about the size of your index finger to the first knuckle. It has a rounded end and it good to keep corners from getting too tight. We can talk porting and touching up the combustion chamber later, this is getting pretty long, but will get you headed in the right direction to get things started.
And one other thing, the "rebuild kits" that are cheap, are just that, unless they give brand names, they are designed for quick flip out the door running to an unlucky buyer.
Thanks Dana44, that's awesome info
 

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Discussion Starter #13
Sorry , by hypertec I meant hypereutectic. Cheers

I'm going with the Enginetech hypereuticric pistons - middle of the road is all I be for what I'm building.

As far as camshaft goes, I was thinking the popular Comp Cams 264, or Erson cam TQ20M.... should work out pretty good with the 9.5 - 10.1 compression I'll end up with after almost zero decking the block and milling the heads. any thoughts on this cam ? thanks
 

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Looking at the profile for the Erson cam, the TQ20M looks to be a very good profile. What transmission are you using with the engine?
 

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Looking at the profile for the Erson cam, the TQ20M looks to be a very good profile. What transmission are you using with the engine?
It's the standard 3 spd column auto. but i guess i can change the torque converter to match the cam if I need to? I'm not sure what the stock converter is rated at...
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Stock converters are rated around 1200-1400rpm, and given this is a fairly healthy cam in the lift and even the duration category, you would probably do best with something in the 2000-2500rpm range to loosen it up a bit and be able to idle without dying as soon as you put her into gear.
 

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Discussion Starter #17
Stock converters are rated around 1200-1400rpm, and given this is a fairly healthy cam in the lift and even the duration category, you would probably do best with something in the 2000-2500rpm range to loosen it up a bit and be able to idle without dying as soon as you put her into gear.
Thanks mate, I'll make sure I do that too .

I'm starting to strip my engine this weekend and then off to the machine shop to have a good look at the block. I ended up picking up a second slant 6 to build rage than pulling my current motor so I don't have any down time during the build.

Thanks everyone for your help, will keep posts up with progress.
 

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And by the way, what is the condition of the transmission itself? Quite often I have found that a good working high mileage automatic transmission tends to last a very short period of time once a good engine is built. If it hadn't been built within say 20,000 miles, it is a whole lot easier to throw new clutches and seals in it to ensure it can handle the extra power you are about to throw at it. At the same time, a shift kit is always a good thing for both the 904 and 727 automatic transmissions, and Mopars are extremely simple in this installment.
 

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Discussion Starter #19
And by the way, what is the condition of the transmission itself? Quite often I have found that a good working high mileage automatic transmission tends to last a very short period of time once a good engine is built. If it hadn't been built within say 20,000 miles, it is a whole lot easier to throw new clutches and seals in it to ensure it can handle the extra power you are about to throw at it. At the same time, a shift kit is always a good thing for both the 904 and 727 automatic transmissions, and Mopars are extremely simple in this installment.
Thanks, great advice. I'll make sure I do that. I have done that in the past with the Holdens that I have put a strong V8 into.
Cheers
 

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Cheers. And keep the questions coming if needed.
 
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