Need cam ideas for my 318 Duster

Well. You have come to the right place.


That would be a minimum of 12:40’s in the 1/4. That makes a nice hot rod without to much camshaft.


I hear ya there. Let’s do this!


P/S or A/C?
I’d guess if it was a loaded car with all the power goodies, it’ll be close to 3500 lbs. if it’s all manual, like mine, it’s 2990 lbs all steel original /6 converted to a 340, aluminum top end and headers. That 340 is lighter than the /6.


Let us know what intakes you have and what carb you would like to finally run with.
I checked what intakes I have:
1. Weiand Stealth, dual plane
2. Weiand 7545 X-celerator, single plane
3. Edelbrock Torker 340, single plane

I have a brand new (NOS) Thermoquad "muscle car" carb, I think Direct Connection sold them back in the 70's. It would be really cool to make it work on the 318. I could try my red QFT 750 DP electric choke but it might be a little big for good response. I didn't have time to go through all my boxes today. I think I have some spread bore carbs in there.
Good, very good. No worries about low vacuum for P/B.

Your kind of split on the gear ratios for the goal. The 3.91 will do for sure. Those 4.88’s will be handy for the track.

Don’t polish the runners.
Polish the chambers

9.0 - 9.5 - 1 will be good. That’s about what the combo hands out.

Excellent


Yes and no. The saying goes, “The juice is t worth the squeeze.”
In other words, the amount of work you do in the cylinders will be a positive move not worth the effort to barely make again worth the effort. If at all. This type of work should be reserved for an all out effort. Not a mild street car. It can also produce negative effects with the piston rings and longevity depending on what is done and how far you go.


A minimum for a solid camshaft I’d consider would be 234@050 on a 110 LSA (perfect for a 2.02 headed 318) with as much lift as I can reasonably get or as much as the head flows well in.

If the flow slows down after .500, let’s say by a few cfm, then a slightly over a .500 lift cam is what I’d look for. If you find a cam that works but the lift is .490, don’t worry about it.

Cam and compression work together to keep the package balanced. My recommendation above will work well.
I run a Hyd. roller @224@050 with a 11.5-1 compression on our top grade of 93 just fine.

You’ll have to shop around. Being the engine is still mild, you can use a stock size 5/16 and as thick of a wall as possible and you’ll be good. Thicker is better though.

Try Smith Brothers. But their are many places.

Personally, I think the 3.91 gear will be great for around town.
However, the 318 will need to turn some good rpm’s at the track and need at least 4.56 gears with your 28” tires to run the time.

The problem is the engine is torque challenged and can use the gears to help release the power quickly to run that time.

I suggest trying the 4.88’s even around town. If you have to go far and must use the high speed roads, these are NOT your friend. Even the 3.91’s will be a bit rough at minimum highway speeds.