Jeep Strokers

I am building a 4.12 ministroker with an Avenger Supercharger. The Aluminum Head from Hesco comes with performance valve springs. Can I run a stock-cam with these springs? If not, can stock springs replace these?

My goal is added power with the stroker and supercharger but I want to squeeze out every MPG I can with it. I want a well balanced Super Stroker.

Before anyone rants about gas mileage and performance being opposites realize this is my build, not yours. I'm trying to do something different and make a 320+ HP engine that will still retain streetability for a daily-driver. Impossible? We'll see.

Here's my latest plan for it:
232 Crank
.030 Silvolite Pistons (4.12 ministroker)
Hesco Aluminum Head
FlowKooler Water Pump
180 Degree Therm.
Flex-a-Lite electric fans set to run at 100% at 190 degrees, 90% at 185 degrees
6 PSI Boost
9.5 SCR (running an aluminum head allows for an extra point of SCR due to cooling and flex properties)
8.0 DCR (numbers configured with a 68-231-4 CompCam)

Fuel Management unknown at this point.

Sounds like a great plan. I would ask Hesco about the springs but doesn't that head use stock size valves?

Yes. It's stock valves but performance springs so you can use an aftermarket cam that isn't supported with stock springs.

I just don't know if that works the other way around.

It seems that every thread I read about cam failure it is always with heavier springs. I would stay with new stock springs or the Mopar performance springs and not a pound more.

It's probably better safe than sorry. I'll have the stock springs from the new 4.0 engine put on the aluminum head after I get back to the US.

Dino reverted back to the stock cam and lifters after he had a cam/lifter failure and went as high as 23 MPG on his stroker.

If I could get 18 or better MPG on the highway doing 65 I would be happy. I had better than that without the 02's connected with 31x10.50's on a 3.5" lift.

This time it will be 33x12.50's on the same lift with bushwhackers and 4.10 gears with a supercharged ministroker.

Coffee Commando wrote:Dino reverted back to the stock cam and lifters after he had a cam/lifter failure

In my case the cause was two bad Crane lifters. The Crane cam still looked like new after 34k miles apart from one flattened lobe so I don't think the Mopar springs were to blame.

Were they collapsed?

I don't think the stock springs will fit the Hesco head. IIRC the valves are stock head size, but the stems retainers and locks are different.

SilverXJ wrote:I don't think the stock springs will fit the Hesco head. IIRC the valves are stock head size, but the stems retainers and locks are different.

Would it be possible to put the stock valve train into the hesco head? I just want to use the stock cam and lifters.

Coffee Commando wrote:Were they collapsed?

One lifter (no.6 exhaust) was collapsed with a missing spring but no wear, while the adjacent lifter (no.6 intake) was cupped and it took out the corresponding cam lobe. I reckon the spring from the collapsed lifter must have got stuck in the adjacent lifter bore and prevented that lifter from rotating.

Cheromaniac wrote:I reckon the spring from the collapsed lifter must have got stuck in the adjacent lifter bore and prevented that lifter from rotating.

How does a spring come out from inside the lifter?

SilverXJ wrote:

Cheromaniac wrote:I reckon the spring from the collapsed lifter must have got stuck in the adjacent lifter bore and prevented that lifter from rotating.

How does a spring come out from inside the lifter?

I imagined it in hundreds of tiny peices, further wiping out the cam lobe next to it.

Coffee Commando wrote:I imagined it in hundreds of tiny peices, further wiping out the cam lobe next to it.

It came out in many little pieces (why? its not under a lot of stress, just keeps the lifter from fully collapsing), and instead of going up the push rod to the rocker, down to the sump and into the pump/filter, etc, it instead migrated over? Not likely.

A more plausible explanation is that the spring was never present to begin with. Had that happen once. Worked fine for a bit then collapsed and spit the push rod out.

All those pieces jumped over to the next lifter. It's those engine gremlins. Stock parts are looking better and better.

Tell me what you guys think about this. I've been over these numbers a lot today in my spare time and this is precisely what i'm looking at having (with the Aluminum head):

.043 Quench
9.88 Static Compression
8.45 Dynamic Compression
6 PSI with Avenger Supercharger

From what I've read the aluminum is supposed to allow for a higher amount of compression by 1 point. But I'm very cautious after 2 cam failures in previous strokers without the supercharger. Granted compression has nothing to do with the Cam wear... I just don't want to tear another engine apart to fix it after I spend thousands on it. D:

These are the final numbers. THe ony way I'm lowering the compression is through the pistons. I got these numbers based off of 11.5 cc's in the stock Silvolite 2229 pistons. This is correct isn't it?