4.0L stroker

[88ranger2.95sp]

The 4.0 has a cylinder bore and stroke that is just as big as your typical 350/351.

Umm.. If the bore and stroke were the same, wouldn't the displacement be the same? 4.0 does not equal 5.7 / 5.8.

But if you have time and money and you want power. Theres nothing better then a v-8

Or if you want something different

Rob

 

[turbo cat]

Umm.. If the bore and stroke were the same, wouldn't the displacement be the same? 4.0 does not equal 5.7 / 5.8.



No because a 4.0 is a 6 cyl and a 5.7 is a 8 cyl

as for the 4.0 being a piece of shat i know for a fact my heads have cracked months ago however ive still been able to push the 4.0 with 5-15 psi over and over again daily for 60+ miles a day and still nothing has broke. I finally parked it to tear it down for some new HGs and Heads/valvetrain

 

[Giant squid]

Small-block Chevy engine has a bore (diameter of the cylinder) of 4". The stroke of the engine is 3.5". The volume of the cylindrical volume is around 44 cubic inches. Since the engine has eight cylinders, each of that volume, the total displacement is 44ci x 8 or around 350 cubic inches. Most of us are also acquainted with the engine as Chevy 350 V-8.
^The 4.0L has a 3.952˝ bore and a 3.307˝ stroke which will give you 41ci per cylinder. pretty close to a 350 bore and stroke. yet a head half the size sits on top

 

[almostclueless]

If a 4.0 is a POS, get rid of your truck and quit complaining, tard.

 

[Wicked_Sludge]

tard.

elegantly put.

the head of the 4.0 isnt "small". its just a v6 head. there is nothing particularly weak about it.

a boosted 4.0 is much more likely to blow a head gasket or vent a piston than it is to crack a head...and since the head gasket can be addressed and the morana kit comes with forged reciprocating components, both of these problems go away with a properly dressed 4.0.

i still agree that there are much cheaper ways to make power...but a 4.3 would definitely be unique.

 

[Giant squid]

I love my 4.0L, I just understand that its not a performance engine. I have a question how much power you going to get outta that 0.3L with the 3 or 4 grand you spend to put it all togather? 15hp? 20ftlbs torque? probly not even. I will say its defintely a unique route to take, and its a novel idea but for what you get outta it and what you pay......... crazy. However, i do hear you arguements and you all have plently of valid points. What can i say im a sucker for v-8's. Sorry for stealing this thread with an arguement!!!

 

[Wicked_Sludge]

i wouldnt look for a huge increase in HP with the stroker, but torque should go up considerably.

the primary advantage to the 4.3 kit is the all forged bottom end though. i wouldnt buy a 4.3 (or 3.3, as my case would be) kit from morana unless i had plans on boosting it...alot.

400 HP would easily be feasible from that kit with a large turbo....it would handle the boost.

 

[dogboy]

But, isn't the main problem with boosting a 4.0L, the heads?

That is what I've always been under the impression of.

 

[Wicked_Sludge]

heads are rarely, very, very rarely, the first weak link in a boosted engine...as is the case with the 4.0.

 

[86_cookiemonster]

Dogboy, I think you are thinking of the 2.9.

I have seen plenty of boosted 4.0 rangers, and explorers. As long as you don't go crazy the heads should hold up fine.

 

[Wicked_Sludge]

ive heard of a 2.9 that ran 20lbs of boost on a stock motor before it vented a piston....

but yes, the 4.0 head is greatly improved over the 2.9's casting.

 

[turbo cat]

my 4.0 has taken over 15 psi a few times and over 5 psi multiple times. As far as the heads cracking the oem heads always crack in NA applications 85% of the time even if the perfromance hasnt dropped off. There are many areas that a 4.0 head will crack. I have beat on my 4.0 having the boost turned down to 5 psi daily and the short block desevres an award. The crank and rods are already forged as well as the pistons are hyperutectic but the castings are beefy as i havent broken one even under the severe detonation that my NA stock motor suffered. My 4.0 is finally showing signs of a blown hg or cracked heads for the l;ast few months ive been driving it. Im finally going to start tearing the heads off tomorrow.

The 4.0 oem heads are not improved even the latter ones. Go to the wrecking yard and pull a bunch of heads and have them checked out most of the time cracks can be found. Going wit ha new cylinder head casting is the only way

 

[Hahnsb2]

Dogboy, I think you are thinking of the 2.9.

I have seen plenty of boosted 4.0 rangers, and explorers. As long as you don't go crazy the heads should hold up fine.

The heads crack, boost wouldn't really cause that. The weak part is cast pistons and the rotating assembly.

 

[turbo cat]

In a turbocharger setup the heat backing up into the exhaust ports would be plenty to overheat the poor cast iron heads no problem. As for the pistons my first 4.0 had the death rattle going up the hill. Sounded like grenades going off in the motor. I pulled the heads to find the the HG blown everywhere and the heads severly cracked, cracked valves, smashed in middle CC....yet the pistons were reusable. Same as my now boosted 4.0 it has rattled a few time on some hard 15 psi pulls. (tip in detonation) yet the motor still spins and spins....The shortblock is not a probelm the top end is. Another 4.0 turbo over at RPS has ran a 4.0 turbo for years until finally a wrist pin broke i belive? he also launches the truck hard with a C6 and slicks to catch the tires in a hurry?

 

[bergz0]

just wondering guys, if you stroked the 4.0 to a 4.3 wouldn't you pretty much be makn it a chevy motor in a way, like the 4.3l VORTEC motor lol? just wanted to get some input