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240racer · 12-27-2002, 09:54 PM

I only have one really concrete reason why the DOHC is better then the SOHC, the others are speculation and in general true. The real reason is: The DOHC head has no lifters, rocker arms or any other unnecessary valvetrain. This is good!!! The cams pretty much just push on the valves. If you want extra valvetrain get a small block, because they make much more power cheaper.

The other reasons like, 4 valves are better then 3 and two cams are better then two are up for grabs. However, the 4v head has more valve area and probably flows better (haven't tested it)

As far as manifolds go, there are more available for the DOHC, sorry.

Also, 10 psi can probably work with the stock pistons (especially if you have the low compression motor) but you have to be very carefull to not detonate or they will melt.

12-27-2002, 09:54 PM	#12
240racer Zilvia Junkie Join Date: Nov 2001 Location: Minneapolis, MN Age: 46 Posts: 574 Trader Rating: (0)	I only have one really concrete reason why the DOHC is better then the SOHC, the others are speculation and in general true. The real reason is: The DOHC head has no lifters, rocker arms or any other unnecessary valvetrain. This is good!!! The cams pretty much just push on the valves. If you want extra valvetrain get a small block, because they make much more power cheaper. The other reasons like, 4 valves are better then 3 and two cams are better then two are up for grabs. However, the 4v head has more valve area and probably flows better (haven't tested it) As far as manifolds go, there are more available for the DOHC, sorry. Also, 10 psi can probably work with the stock pistons (especially if you have the low compression motor) but you have to be very carefull to not detonate or they will melt. __________________ Adam '89 coupe KA24DE+T 14.1 @ 104 MPH '88 Celica All-Trac turbo stock, but no more ecu codes!!