dusterbuster5621 said

Hi All, I have a 318 in a 1975 Duster with the following specs: 10.3:1 static compression, 4 barrel dual plane air gap intake, Clevite hydraulic flat cam w/226 duration and 0.453 valve lift, headers, edelbrock carb, stock bottom end, some head work I did on my own, and at 5200 ft in elevation. I estimate I have around 320 hp at the crank based on those fun online engine hp calculators. Here's what I want: I want the engine to be more reliable (I have been getting vapor lock in the summer) and I want 400 hp at the wheels and I want to do it in the easiest way possible (not the cheapest) and I do not want to run NOS. I have been looking at Holley's Sniper EFI system along with their hyper spark set-up to increase the reliability. For those extra horses I am considering a Paxton super charger. Again, not cheap (around $10K in total for both EFI and charger) but easier than rebuilding an engine or so I think ha. A few questions I have below:

• Is this really stupid? I was thinking I could keep the boost pretty low maybe less than 4 PSI if I opt for a bigger pulley on the charger?
• If I was running 4 PSI of max boost, what octane level would I need for this set-up? I am okay with using 91 and then mixing in something like torco to increase the octane level.
• The Paxton kit requires a hole be made in the oil pan. Does anyone have experience doing this? Curious to hear how you did it? Did it with the oil pan still on the car? Remove the oil pan and drill it?

I'll pay to have the car dynoed and tuned by someone with more experience than me after I get everything installed.

This engine is not the end goal for the car. I want to build a 360 set up to take on boost in the future (650 hp) but this is maybe 5 years down the line. I am hoping that the supercharger and holley EFI system will be transferable to that new engine. For now I just want the car to be more fun and not worry about breaking down. Not going to be a drag car. Just want to feel some punch driving it around :)

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1. Look up Rusty Rat Rod's guide to hot rod bliss.
2. Look up the requirements to run forced induction, you don't want to start with a high compression engine.
3. Get a bunch of books on small block mopars, put them in the bathroom and read them every time you are on the throne.
4. There are easier options than $10k to supercharge a 318. Look up blueprint engines, they have an ad here, and a dedicated forum here.
5. For that kind of money you could easily drop a third generation hemi in your car. 392 Crate HEMI Engine
6. For that kind of money, you could drop a b or rb in as well.
7. Check out the 10, 11 and 12 second combos. That will serve you better than building for a horsepower number, there you will learn about gearing, suspension and torque converters as well.
8. Work on your suspension and braking capacity before you worry about going fast. Being unable to stop or turn to avoid some kid on a bike will kill your soul as you sit in prison and all that power under your right foot is no consolation. Don't race on the streets.