Been lurking too long.....have a question about 2.3 heads

[hat_man]

Hello all,

I've been lurking here and using all the info I can to help keep my '97 Ranger on the road. It has 217k miles on it now and runs pretty good. I have never had the engine out (I bought it with 97k on it) and engine wise, I have only had to replace the timing belt and alt.

I am wondering if it may be time to pull the engine out and have it gone through. Things like having the cylinders trued up and new rings,gaskets, and main seals (the front one seems a bit "leaky",and anything else that it may need.

The question I have is about the heads. After reading the Ranger 4cyl. Lima tech area I come up with this information.

Heads: All 2.0/2.3/2.5 heads will physically bolt in place of each other.

Truck D-port - 1989 - 2001 Ranger. The 1989 - 1994's and 1995-2001's have different combustion chambers and ports. It is thought that the newer head is better designed.

The 2.5 liter version was only offered from 1998 To 2001, when the engine was replaced by a 2.3 liter DOHC Duratec based engine. The 2.5 was a stroked (by 7 mm) version of the 2.3 OHC Ford Ranger engine. It also used higher flow cylinder heads for better intake and combustion..

So here is the question.....What is the difference in my 97 2.3 head and a 98+ 2.5 head? Are there design differences in the 2.5 head that make it higher flowing and have better combustion characteristics than the 2.3? Is it specifically tuned to the 2.5 block? I mean, it may physically bolt in place but maybe isn't a good match?

My 2.3L shows a 9.4:1 compression ratio. If the 2.5L head does have a better design what would happen if I put it on my 2.3L? Would it change the compression ratio? If the compression ratio is lower with the 2.5 head could it be decked to get some of it back?

I guess the real question is are there any gains to be had from putting a 98-2001 2.5L head on a 97 2.3L block?

Thanks for the info. I'm sure I'll be back to ask more silly questions.

 

[scotts90ranger]

your head is the same as a 2.5L head.

The engine is probably fine, if you want to see what kind of shape it's in, get a compression tester and see what each cylinder does, if it's in good shape they will all be within about 5% of eachother. a leak down test would tell you more, but a compression tester will give you a quick easy answer.

The front seal can be changed with the engine in the truck fairly easily if you take the timing belt off, the front seal housing comes off pretty easy.

 

[Sunk]

I just replaced the head on my truck a couple weeks ago (immediately prior to turning over 200K) and it looked great on the inside, cross-hatching still easily visible and no ridge at the top of the bores.

The head I used was listed for a 95-97 Ranger, the only difference I found was the 2 bolt holes for the water neck are larger on the new head. This wasn't a problem except that the bolts that threaded into these holes didn't fit through the holes in the water neck. A couple minutes with a drill solved that though, and you're doing the opposite, so you'd just need smaller bolts.

 

[Mikel89us]

There is a difference in the 2.3 and 2.5 head. The 2.5 head has a redesigned lifter placement that moves it closer to the center of the head and increases the rocker arm ratio. All of the 2.3 and 2.5 Roller cams are the same, but the 2.5 head achieves .400" valve lift, instead of the 2.3 heads .355" valve lift. thats where the difference is, and you can do that swap and bigger injectors to gain some power, or buy a new cam from somewhere. The head swap wont cause tuning issues as wont any 2.3 cam under .420" lift. after that a tuner is required.