[scxc15]

Whats the diffrence between 2valve and 4valve engines. I mean besides the fact that one has two more valves. Like can you make a 2v engine a 4v somehow?

[RandoGT]

the 2v is SOHC and the 4v is DOHC. the 2v has two cams and 4v has 4. i'm guessing same bore and stroke, different heads. not sure what else, assuming same year of course

[Regency 2007]

It's different heads. Consisting of valves, cams, intakes, exhausts, ect.

4v will make more power, better powerband, and will rev higher.

[scxc15]

The 2v has one cam and the 4v has two cams actaully. So I could take the heads off a 2001 4v on a 2001 2v and then it would be a 4v, and add another cam? seems too simple lol....

[weems]

Originally Posted by scxc15 The 2v has one cam and the 4v has two cams actaully. So I could take the heads off a 2001 4v on a 2001 2v and then it would be a 4v, and add another cam? seems too simple lol....

no , the 2v has two cams and the 4v has 4

[Uncle Humjaba]

Originally Posted by scxc15 The 2v has one cam and the 4v has two cams actaully. So I could take the heads off a 2001 4v on a 2001 2v and then it would be a 4v, and add another cam? seems too simple lol....

i could see how you might make this assumption, because Single Over Head Cam (SOHC) and Double Over Head Cam (DOHC) are kind of misleading... this only means that there's 1 or 2 cams over each head. Since we have v8 cars, there are two heads (one on each side) and thus a total of 2 cams on 2v cars and 4 cams on 4v cars.

my 4cyl geo storm is DOHC but only has two cams because it's a inline 4. make sense?


a question i have though: are all DOHC cars 4v? my geo has 16 valves total = 4 valve per cyl...

[StangAddiction]

The 2v heads (SOHC) have 1 cam each and 2 valves per cylinder. There are 2 heads on the v8. DO some math and you come out with 2 cams, and 16 valves. The 4 heads (DOHC) have 2 cams each and 4 valves per cylinder. Totals out to 4 cams and 13 valves on those.

As for the heads themselves, the 4v heads have larger combustion chambers which allow for lower compression ratios, so generally they're a favorite with those interested in boostin. Unfortunately, the 4v heads are more complicated have have more parts, and are therefore,the aftermarket is more expensive on em.

[ChrisJ]

I found an exact hot-to on another forum...

I posted it over here...

Click Here For The Post

[TheBusher]

Originally Posted by StangAddiction The 2v heads (SOHC) have 1 cam each and 2 valves per cylinder. There are 2 heads on the v8. DO some math and you come out with 2 cams, and 16 valves. The 4 heads (DOHC) have 2 cams each and 4 valves per cylinder. Totals out to 4 cams and 13 valves on those. As for the heads themselves, the 4v heads have larger combustion chambers which allow for lower compression ratios, so generally they're a favorite with those interested in boostin. Unfortunately, the 4v heads are more complicated have have more parts, and are therefore,the aftermarket is more expensive on em.

32 valves not 13 valves

[StangAddiction]

Originally Posted by TheBusher 32 valves not 13 valves

typo.....yeh thats a pretty big difference...

13 valves...sounds like some lop-sided cylinders to me...