what cam to choose

[hodggi30]

Hi all i posted about an engine fire 92 mazda navajo 4.0 manual 4.10 rears before. Got my motor out to clean it up a bit and ive decided at a 120,000 maybee time to check cam and chain. Iwould like to put in a aftermarket cam for a better sound. But i dont wanna change pushrods or loose a lot of fuel economy so could some one help. there are just too many options.

 

[boggs1227]

120k is to early to be thinking about that stuff,these engines run well over 200k-300k so @ 120 it's just now broke in .changeing the cam to get a better sound ?! ...go witha performance muffler... also if you really feel like you need to check the cam and chain for some reason ( not makeing any noise's are they ??) you will need to replace the timeing chain cover gasket if it's taken off the block (even if you dont change out anything).to replace the cam properlly not only will the cam be replaced and a new chain and sprokects but you'll have to also replace the rockers ,push rods and most likelly the lifters + get it re-timed .


all this = $$$$$$ , so if your really dead set on a cam then go for it, but if it were me i would leave it be ,you'll have better fuel economy and put a lot less stress on your engine.

 

[ilh]

hodggi,

cams! now you're up my alley. i live eat and breathe those badboys.
do you know anything about cam specs? if you do:

Comp Cams 49-422-8 is a good looking cam to me.
1200-5200rpm range, 215/224 duration @ 0.050", 0.500"/0.500" lift. 112 LCA, 108 ICL. Comp says "Hydraulic Roller - Good in Explorers and Rangers with aftermarket chip. Strong torque & mid-range. "

You absolutely MUST replace the lifters as your used one will have a wear pattern and it will immediately beat the **** out of the cam. Once you lose 0.002" off the cam, you lose it's case hardening and the cam wears right out. then you get junk lobes and need a new cam again. dont bother saving the timing chain either, that's classified as "cheap insurance". inspect the crap out of the pushrods and rockers while you're in there, no point in re-using junk.

basically lay $500 away to do the swap cause you gotta change the fluids and stuff while you're at it. the manifold and valve covers have to come off as well so you may as well replace those gaskets.

just my $0.02.

 

[seth247]

the comp 422 requires new CUSTOM pushrods. And dual springs, which the heads must be machined to accept.

The comp 410 however runs stock rods and springs but your in there any way might as well replace them.

And yes, Lifters MUST be replaced. either way.

The 410 is much more likeley to pass emisions.

 

[hodggi30]

thanx

thanx guys that helps alot. I looked at my setup and i was suprised that all the parts showed very little wear. I prob. will get a cam though this motor sounds kinda plain but runs really good will these cams change the sound, gotta good muffler but it doesnt do that much for it.

 

[Blacksheep Josh]

Yup, when I get a 4.0 engine to rebuild, I'm going to be building it up so I don't lose my X as the DD. Most likely the 410 cam as well... but not sure. Creager's thread has me ready to drop about 3 grand into it..