Crate la 360
does anyone have an idea on the probable horsepower of a stock style crate 360 with a 4 barrel and headers. No other mods.
Thanks
MRO
Now on to a question for you without the serious waste of band with of copy and paste....
Your asking about a stock style 360 with the addition of headers and a 4bbl.
This is a loaded question with to many variables to accurately answer. If you could narrow down what year 360 you have to start with, it would greatly help since there are a few versions. La & Magnum. Then there are the crate engines. Commando and Magnum versions.
What header? Shorty? Long tube? Equal or unequal length headers? 1-5/8 tube or 1-3/4 tube? Which is better? Is it a stepped headed?
The same goes with a 4bbl. carb. What carb? What size? What manufacturer?
Also add in what intake manifold. Is there a spacer used? What kind? By whom?
As a in general answer, the typical cheap header everyone hates that has been made since day one @ 1-5/8 tube size used with a true dual 2-1/2 exhaust pipe can add 20 - 25hp. Adding a small street bound 600 cfm carb can add another 15 - 20 hp depending on the intake.
Guessing you have great material on the car for the max listed power gains of 45 - 50hp is closer to a dream than reality. Mostly because most 360 engines do not even have an 8-1 ratio but often lower. I’ve measure as low as 7.8-1 on a dead stock engine. When you out it back together again, if you don’t use the same gasket the factory did (the very thin one!) but use the cardboard thick Fel-Pro, your ratio goes less than 7.5-1.
(You can run that on Yak piss by the way!)
Typically you can get in the area of, + or - a few hp of 280hp.
Add a modern cam that is close to the OE 4bbl. cam specs and you can have the combo to start working for you a bit better. Raise the ratio a point + and your in the neighborhood of 320hp.
I hope this helps shed some light on the subject and offers some direction. Though I’m sure it also opened up a can of worms of questions. Which is a good thing.
