Edelbrock 4.0L head soon to be available.

[jsawduste]

I`d still want to check valve spring rates.

Those flow rates are OK but nothing special. IIRC a decent 7120/06330 isn`t to far off those numbers.

[FlyinRyan]

I`d still want to check valve spring rates.

Those flow rates are OK but nothing special. IIRC a decent 7120/06330 isn`t to far off those numbers.

You're absolutely right. However, if experience tells me anything, it will show that the Eddy head will ultimately have more meat for superior flow...Flow that may only be achieved on an OEM-based head with additional welding or epoxy. The production Eddy heads for Chryslers have never been all that stellar out of the box, it's what they are with some time with the grinder that makes them noteworthy.

[jsawduste]

Like dyno numbers flow numbers are only comparative tools at best.

While Edlebrock advertising claims to be measuring at 28 inches vacuum I do not know what vacuum the other numbers that were published were at. A bit on the lazy side today to do much digging and to old to recall details.

Also find it curious that the flow advertisement stops at .400 and appears to drop slightly from .300 to .400. To many variables and unknowns to make assumptions.

Ryan is correct though, a base to mold from.

[sly-jeeper]

[Cerveja]

This is great news to see the Edelbrock head is out in the market and in production. My 4.0 is a few weeks away from coming out and getting stroked due to an increasing loss of oil pressure (and an increasing appetite for coolant) over the last few years. This thread has been great, read it front to back, lots of great information from lots of guys with varying experiences. So it looks like there are a couple of questions still looming. There is some concern that the spring rate may still be too high which could lead to excessive cam wear, especially in a cam with narrow lobes. Could roller lifters alleviate this concern? The roller width is generally narrow'er anyways as it must drop thru the lifter bore. And the fact that it's a roller should eliminate the sliding friction at the cam surface. This should eliminate the smaller contact path and the concern that the lifter would not rotate as easily. Yes, roller lifters are quite a bit more coin than a standard solid or hydraulic, but if it saves swapping burning up my cam every 30,000 (Or ever for that matter) I probably don't mind fitting it into the budget.

The next concern that I would have is longevity. I haven't pulled my motor yet, but I am fairly certain I have one of the crack prone factory heads thus explaining the disappearing coolant. Is the general consensus that Edelbrock has changed the casting to eliminate this weakness that has plagued many 4.0's in the past? Is the assumption that the softer aluminum is more compliant and no longer prone to cracking?

[Retlaw01XJ]

Regarding the crack-prone head.... Jeep improved the casting in 2002 with the 'TUPY' version of the 0331 head. Edelbrock likely designed their head properly so this shouldn't be an issue.
Roller lifters would sure be nice! They do weigh more, and if they have a faster open/close rate, they may require more spring pressure than our flat tappets. Rollers would eliminate the cam lobe-wear issue. I don't know if there will still be a problem with cam journal bearing wear.

I'd really like to see a dyno comparison between the stock head and the alum.....

[SilverXJ]

You can't just throw roller lifters on a flat tappet cam. A quick death for all components will ensue. Roller cams are ground with a different profile and any worth their salt are ground out of a billet blank. 505 offers roller cams, but they are just the usual flat tappet cam core reground to a roller profile. Last I looked into a new custom billet roller cam it was $1000 just for the blank.. no grinding nor lifters.

[sly-jeeper]

Personally I chose the Mopar 229 because its a OEM type cam. And went with the Mopar performance springs that closest resemble stock even though they are rated for max .430 lift they clear fine at .440 lift and the valves do not float @ 5300 RPM. I also throw a bottle of zinc additive in with every oil change for extra insurance. This cam very closely resembles stock but has slightly more duration at lift and slightly more lift.

[Cerveja]

You can't just throw roller lifters on a flat tappet cam. A quick death for all components will ensue. Roller cams are ground with a different profile and any worth their salt are ground out of a billet blank. 505 offers roller cams, but they are just the usual flat tappet cam core reground to a roller profile. Last I looked into a new custom billet roller cam it was $1000 just for the blank.. no grinding nor lifters.

So do you not recommend the 505 Set? I like the Rollers for keeping the friction down and will likely go H-S or Y-T 1.6 Roller Rockers up top. I realize that this may be overkill as these engines aren't super high revving monsters, but feel if I need to rebuild the motor, I want it to be better than stock. It's going in my '00 Cherokee which is not my daily driver, but is used mainly on the trails and crawling rocks. Unfortunately I don't trailer it, so the motor has to be reliable enough to spend more than a few hours cruising at +Highway Speeds before she can creep along in 4Low.

[jsawduste]

So do you not recommend the 505 Set? I like the Rollers for keeping the friction down and will likely go H-S or Y-T 1.6 Roller Rockers up top. I realize that this may be overkill as these engines aren't super high revving monsters, but feel if I need to rebuild the motor, I want it to be better than stock. It's going in my '00 Cherokee which is not my daily driver, but is used mainly on the trails and crawling rocks. Unfortunately I don't trailer it, so the motor has to be reliable enough to spend more than a few hours cruising at +Highway Speeds before she can creep along in 4Low

I would not let 505 touch my weedwacker, no

HS yes YT `eh.
no so
no big deal if done right

[Cheromaniac]

Well I just got off the phone with Summit and ordered part # EDL-50169 Edelbrock Jeep 4.0 cylinder head. They said it should arrive in two to three weeks. We will see. Price was steep at $1489.97

That's exactly the price I was expecting, and $500 less than Hesco's.

#50169: Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28" H2O
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 66 123 179 221 241 237 -
Exhaust 63 103 127 144 151 155

You could easily beat those numbers by porting a stock 7120 or 0630 head so I wouldn't get too excited about them.

[PseudoSport]

I'd really like to see a dyno comparison between the stock head and the alum.....

If someone was to do a dyno comparison between a stock head and the aluminum one on a stroker, how would you want the rest of the engine set up? It seems like most people use an aftermarket cam when they build a stroker. Cammed stroker with stock head and upgraded valve springs then same cammed stroker with aluminum head?

[jsawduste]

I`ll throw this out. Totally conjecture but educated conjecture.

Apples to apples with the only difference being the head.

The LS style chamber being the biggest difference I would expect about a 10-15 hp advantage to the Edlebrock. Reason being again the revised fast burn chamber (FBC) and a bit less shrouding on the intake valve.

Add the FBC chamber with a matching piston, tight squish and a good tune your up another 10-15 hp.

Where it will get interesting is when you can take advantage of the Edlebrock casting and do some port work. Herein lays the biggest gains. Combine porting, FBC, piston, compression and tune I don`t think it unreasonable to expect a +50 hp gain. This of course is dependent on having an induction and exhaust capable of moving enough air.

Issue I see is the potential to lose some bottom end if you run enough cam to take advantage of the ported head.

There is going to be a balancing act between camming, VE and grunt that only time will exploit.

[jeepxj3]

Got a new JCWhitney catalog and they show the Edelbrock head under 'New Performance Products'.
They have it priced $646.70-$1511.89

Does that mean that there will be a 'bare' casting available for $646.70 ?
I would buy that.

[sly-jeeper]

I believe they do have a bare casting