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F/A Tech

F/A Tech

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Hi
I want to keep the slant but want to upgrade with headers & 2 barrel. Do I need to do anything to the motor ? Will performance upgrades be the same for a 198 vs 225. Took the car to 2 shows in Vancouver this year. Everybody loves the slant motor. Quite crazy with all the V8s on show.
 
To get good answers to the question we need more info. What is the build on your 198 slant? Is it stock or ??? What is your intended use, and what car is it in? No matter what, the 2-bbl intake is a good idea, but unless you are building a dedicated race car there are better options than headers. More details will help us steer you in the right direction.
 
halfafish said:
To get good answers to the question we need more info. What is the build on your 198 slant? Is it stock or ??? What is your intended use, and what car is it in? No matter what, the 2-bbl intake is a good idea, but unless you are building a dedicated race car there are better options than headers. More details will help us steer you in the right direction.
Click to expand...
Hi, Thanks for reply. 1973 Duster 30,000 miles just regular use. no racing. looking at some of the set ups from Austraila.
Thanks
 
OK, that helps.

And I'm jealous, I had a 73 Duster /6 auto way back in the day. Wish I'd never let it go. Yes, upgrades motor-wise are similar between 198 and 225. The 198 will rev a little bit better/faster/higher, otherwise there's not a ton of difference.

Seriously, living in Canada, you will have to deal with cool to cold driving conditions. As if you didn't know. :rolleyes: Dutra Duals are a FAR BETTER option than headers. Headers on a slant are for all-out racing or a seriously pumped up street car. They are a waste of money and serve no purpose on something that's stock to moderately warmed up - and you will want the intake manifold heat system that's retained with the Dutra setup. Do the HEI conversion. The 2-bbl upgrade is a good thing, whether a super-six or aftermarket. Find a super-six distributor and do the recurve covered over at slantsix.org. So far, we're only talking about bolt-on stuff.

If you decide to get into the engine the head is the next candidate for improvement. It is the hindering factor in creating a good running slant. A nice street-level pocket porting job, larger valves, and getting it shaved to get your compression to about 8.2 (DYNAMIC not static) will make a huge difference. Depending on what you do, the next step is to get your cam reground to one of the moderate grinds by Oregon Can Grinding.

Upgrading the exhaust for better flow would be the last step. Happily, these improvements are all fairly reasonably priced.
 
Just a FYI. Only difference between a 198 and a 225 is the crankshaft and connecting rods. Everything else is the same.
 
Charrlie_S said:
Just a FYI. Only difference between a 198 and a 225 is the crankshaft and connecting rods. Everything else is the same.
Click to expand...

Is the piston pin position the same? AFAIK dropping a 225 crank into my 198 with the 198 rods would have the pistons smacking the head.

Howdy Charlie! Long time. Glad to see you are still alive and kick'n
 
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Pistons are the same for 170, 198, and 225 engines. You need to use the crank, and rod combo, for the cubes wanted (also block for the 170).
 
Rug_Trucker said:
I thought using the 198 rods required either a custom piston with a shorter piston top to pin height for the 225 crank?
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That is correct.
So I can flip my 198 over and drop in a 225 crank? Slantzilla years ago told me "no."
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NO
198/225 block
225 crank, 225 rods, stock slant pistons= yes
198 crank, 198 rods, stock slant pistons= yes
225 crank, 198 rods, stock slant pistons= no
198 crank, 225 rods, stock slant pistons= no
 
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