Execut1ve

Here's a question sure to spark some lively discussion:

Is it easier to build a 400+ HP naturally aspirated engine with the 351 as the starting point, or the 302?

I'm interested to see some thoughts from folks more knowledgeable than myself!

qdeezie

The 351W because you'll actually have torque and it's easier to get there. You can get 400hp out of a 302, but you'll be slack on torque.

David Young

351

Execut1ve

Thanks for the answers guys.

I have the 302 already so I am weighing (in fantasyland, of course ) the cost of acquiring a 351 plus the cost of the work that will have to be done to it.

As far as aftermarket performance parts cost and availability, I figure the classic 302 has to be best, but the 351 can't be far behind.

I'm guessing to hit 400HP will require at least stroking, heads, camshaft, and exhaust headers on either engine, correct? In addition to probably beefing up the trans... perhaps I should start saving now lol

BLDTruth

I have had this internal debate with myself several times.

IMHO a 302 is a mustang engine in a truck. You can trick it out but it will never be a truck engine.

A 351 is the bare minimum if you want to build something that can haul ***** and possibly tow a little weight behind it too.

If it were me, and I was starting from scratch, I would start with a 460. Requires more work but like they say there is no replacement for displacement.

Execut1ve

I've considered that as well, but it seems like quite a bit of added complexity since the 351 is basically a drop in swap (aside from possible MAP to MAF issues maybe) whereas with the 460, I'd imagine you're swapping in a new computer, wiring harness, and trans too

BLDTruth

Yep it's not any easier that is for sure. But at some point, if you are working with a 302 or a 351 that is putting out enough power, you are also going to be working with more robust injectors, which is going to require computer upgrades anyways. I've read a lot of guys will build up a 351 or 302 and use a 460 computer to run it so it will actually deliver the fuel it needs.

As far as transmission goes, if you are building a 302 or 351 up to 400+ hp, then I'd wager you would be doing an upgrade to the tranny as well to handle the power. The M5OD in my truck can only handle up to about 300/300 hp/torque before it will blow up. I would imagine upgrading the tranny would be the cheapest part of the project.

The ideal situation would be a 460 swap and a MAF conversion - would be expensive but would also be the ideal combination to allow you to pretty much do whatever you want. We have a guy in here who has a flareside with a 460 swap MAF conversion. I'd like to see how that thing presses your back into the seat

Execut1ve

hmm... speaking strictly about the 351, if you are already planning to do a cam swap and stroker kit, does it matter if the engine starts as MAP? Is anything else different between the MAP 351 of pre-1995 and the MAF version of 95 and 96? If not, it'll be a whole lot easier to source an engine to start with!

BLDTruth

I don't think so - only difference would be wiring - but I would not take my word for it - someone else should chime in and confirm.

qdeezie

You can start out with your engine as map. As long as your cam has vacuum, you shouldn't have any idle issues. The main thing is make sure you use an IAC bypass plate so that your engine gets enough airflow at idle and not surge.