SVO heads or PI heads?

Dalamar · Mar 1, 2008

the SVO's flow better all around, but are $$$

steedastang · Mar 1, 2008

Mustangman9812 said:
steedastang said:

Mustangman9812 said:

PI is the way to go. You still have to use the NPI intake dont you? That is going to kill the heads because the intake dont flow good at all. Also the SVO heads are like $900 a piece i thought. If you can get them for $900 both complete thats great but PI heads are still cheaper and you wont have any guess work, you know it works because to many people have done it. So i would go with PI Heads outright :thumb:

Edit: Also if you are going with the blower or not PI's are better, the raise in compression does have alot of effect on the outcome and that willl be more power N/A than the SVO's. With PI's the only thing you need to do is run 93 octane.

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I dont know where you heard this stuff? Especially the blown part. Good luck running anything but a small amount of boost on a pi swap. Your tune will have to be crap.......

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Like I Said, You Learn Something Everyday! :whip:

Sorry,

Looks like i came of a bit rude. PI heads, when added to an NPI shortblock raise the compression quite a bit (around 10:1 I think but may be wrong). This isnt ideal for a blown application because blowing the engine multiplies this situation. Add fuel to heat and super compressed air and you sometimes get an explosion. In an engine this can happen before the spark plug fires which is called detonation. It happens when the piston is moving up during the compression stroke which can cause separation of internal parts due to them being over stressed. To keep detonation at bay you typically have to reduce timing out the ying yang or run a small amount of boost.

I love having svo heads because 99% of car guys and 50% of stangers dont even know what they are! Its kind of funny. Guys will be like "oh thats cool" without a clue in the world.

Good luck in what ever you do!