Cylinder heads

[Zer0PSI]

How much power can you make with the stock "D" port cylinder head w/porting?? I am assuming you can make more power w/ the "D" port head than with the oval port head.

 

[Mark_88]

Not sure if there is a big difference between the two power wise as long as you port match the intake...I've read posts from people here who claimed to have attained close to 200 HP (or more maybe) on an "O" port head with some serious porting and cam changes...can't remember who posted that but it was a few years ago.

I would be happy with about 140 HP on my "D" port head but I think that would require a different cam and bigger valves...I just had the head rebuilt and did some P&P myself but did not get the bigger valves or a different cam...mine is a roller cam and apparently they are better.

But it boils down to changing cams and valves...if that helps.

 

[Mutant Pony]

The d-port heads are the worst "as cast" heads. They NEED a good bowl cleanup. Bigger valves would help but, 150 should be obtainable without them. The d-port EFI intake is the best possible intake. If you are going carburated The EFI lower plenum can be modified into a 4 BBl intake fairly easily. A 390 Holley should put you right near 150HP with a free flowing exhaust. I can't say by experience because I haven't yet run a d-port. I will be this summer though. scroll through this forum and look for "real 4 cyl part II".

 

[94_Ranger]

Did any years come with an aluminum head? And what heads will fit on what blocks?

 

[Dave R]

Did any years come with an aluminum head?

No.

And what heads will fit on what blocks?

Any Lima (2.0/2.3/2.5) will fit on any block. Any exhaust manifold will bolt to any head. Intakes are another story entirely, most of them only fit, correctly, on specific heads.

 

[Mutant Pony]

Did any years come with an aluminum head? And what heads will fit on what blocks?

They did not ever come from the FACTORY with aluminum heads(thank God!!!). Esslinger has two or three different aluminum heads available. Frpp has one of Esslingers heads in their catalog.
Also there is a Volvo dohc head that will bolt on to the block, there is a write up at RPS.

 

[shadetree]

Esslinger says this about heads:

We feel that the D-port head flows the best of all the 2.3 heads, (ported and polished or stock).

The D-port open chamber head is excellent for totally stock classes, where no head modifications are allowed.

The oval-port head is the easiest to locate and least expensive and still makes good power once properly ported and polished.

There are others who claim the round-port heads can be made to out-flow all the others with extensive head work, but one needs to be very experienced in attempting this. shady