Jeep Strokers

I'm inclined to make a variation of a 4.6 or 4.7 Poor Man Stroker based on Dino Savva's recipe, but I need to learn more. I want a good daily driver for city streets (including short trips), level highway, mountainous highway, and offroad.

Typical rpm will be from 1000 to 1600 in city, 1800 to 2400 level highway, 2400 to 3000 mountainous highway, and occassionally 4000 rpm on mountain highway on ramps. I might occasionally wind it up to 4500 rpm when passing. Off road it needs to have good torque from 1000 to 1600 rpm. I mean good compared to stock 4L.

I want it to be a long rod engine using stock 4L rods.

Various recipes list pistons of 3 types: hyperatic Silvolite, cast, and forged. Why is one type piston listed for a given recipe and another type for another recipe?

My knowledge is limited, but I'm learning. I've been reading about those different families of pistons in Wikipedia and at Summit Racing.

I want my stroker to be naturally aspirated 4.6 or 4.7 long rod with stock 99 cam and 62 mm TB. What would be the pros and cons of a 4.6 vs 4.7 Poor Man?

At this time, I'm thinking Keith Black hyperatic Silvolite pistons would be ideal for a naturally aspirated daily driver. Is that correct? Please explain.

Part of my goal is 9:1 or 9.25:1 SCR so I can use 89 octane from sea level to 3000 ft (coastal mountains). Advice? If I get Keith Black Silvolite pistons, which part # should I get?

The Keith black pistons are forged. The silvolites are completely different. They are used with 4.2 rods and thats whats called a short rod stroker. The Keith blacks are used with the stock 4.0 rods and are whats called a long rod build. Theirs 2 differences between pistons. Pin height which affects your quench. And material, the forged are the strongest material thats why people do long rod builds when their going to use boost or forced induction. But you don't have to. I did the 4.6 modified poor man stroker using KB 944 pistons a Scat 258 crank and the rest of the parts are stock.

From what I've seen at Summit Racing, Keith Black makes both Silvolite and Forged pistons.

I was reading at Summit Racing where they offer many different Keith Black Silvolite Jeep 4 liter pistons (for strokers I assume?). Like half a dozen choices: http://www.summitracing.com/search/bran ... /make/jeep

I want a long rod engine using stock 4L rods. Are there Silvolite pistons that would work with long rods?

Is there some reason why a forged piston would be better with a long rod?

What would be the pros and cons of a forged piston vs hyperatic-Silvolite piston with a naturally aspirated long rod engine?

I didn't realize Keith Black made the silvolites too. But no to my knowledge you cant use any of the silvolites in a long rod build only the forged will work. Look up short rod vs. Long rod build on this site and read read read. All the questions you have like why the silvolites don't work in a long rod build have already been answered more in depth than I can without me going through and copy and pasting it all.

charley3 wrote:Part of my goal is 9:1 or 9.25:1 SCR so I can use 89 octane

I don't think this will happen using a stock cam shaft. Too much DCR unless you stay on the low side of 9:1.

charley3 wrote:I want a long rod engine using stock 4L rods. Are there Silvolite pistons that would work with long rods?

Nope. The long rod needs either the KN 944/945 or a custom piston. Both options will be forged.

Is there some reason why a forged piston would be better with a long rod?

A forged piston is considerable stronger than a hyper or cast piston. However, the draw back is extra clearance when cold, which will make the engine noisy on a cold start until about 2 minutes after start.

If you want a long rod you would have to go with either the KB944s or a custom piston. Or a custom rod length to accommodate the hyper's pin height and still clear the deck. But then you are talking about $$$$.

Personally I would go with a Sealed Power hypereutetic piston over a Silvolite. While Keith Black makes some nice forged pistons their hypers leave something to be desired.

charley3 wrote:I'm inclined to make a variation of a 4.6 or 4.7 Poor Man Stroker based on Dino Savva's recipe, but I need to learn more. I want a good daily driver for city streets (including short trips), level highway, mountainous highway, and offroad.

Typical rpm will be from 1000 to 1600 in city, 1800 to 2400 level highway, 2400 to 3000 mountainous highway, and occassionally 4000 rpm on mountain highway on ramps. I might occasionally wind it up to 4500 rpm when passing. Off road it needs to have good torque from 1000 to 1600 rpm. I mean good compared to stock 4L.

I want it to be a long rod engine using stock 4L rods.

Various recipes list pistons of 3 types: hyperatic Silvolite, cast, and forged. Why is one type piston listed for a given recipe and another type for another recipe?

My knowledge is limited, but I'm learning. I've been reading about those different families of pistons in Wikipedia and at Summit Racing.

I want my stroker to be naturally aspirated 4.6 or 4.7 long rod with stock 99 cam and 62 mm TB. What would be the pros and cons of a 4.6 vs 4.7 Poor Man?

At this time, I'm thinking Keith Black hyperatic Silvolite pistons would be ideal for a naturally aspirated daily driver. Is that correct? Please explain.

Part of my goal is 9:1 or 9.25:1 SCR so I can use 89 octane from sea level to 3000 ft (coastal mountains). Advice? If I get Keith Black Silvolite pistons, which part # should I get?

Why would you want to use a stock cam with the increase in engine size?You could easily go bigger and get more without loosing anything on the bottom end.Building a stroker of any sort with a stock cam is sort of counter productive.The increased cubes will automatically want more than the stock cam can do.Especially with the broad rpm range you are talking.The bigger cam will also let you get away with running a higher scr.If you have to buy a throttle body buy at least a 68mm.

Radioactivexj wrote:I didn't realize Keith Black made the silvolites too. But no to my knowledge you cant use any of the silvolites in a long rod build only the forged will work. Look up short rod vs. Long rod build on this site and read read read. All the questions you have like why the silvolites don't work in a long rod build have already been answered more in depth than I can without me going through and copy and pasting it all.

They don't, United Engine and Machine own KB, Silv-O-Lite, and Icon:
https://www.uempistons.com/

I have the IC944s in holes that are 0.0035" over and I do not hear them when cold. They supposedly used an alloy that expands about the same as a hyper so they do not have the noise of a regular forged. I think my engine fits what you are looking for. Mine has the 944s a Crower Baja Beast and 46.4Lb injectors. It has run good for about 500 miles but now has some sort of fuel issue.

How about 4032 alloy pistons with long rods?

I read in another JS thread that 4032 pistons might work with long rods. I read at Wiki that 4032 alloy is for performance hyperatic pistions that have 11% silicon in them, which is less than the usual 16% in a typical hyperatic piston.

So the 4032 alloy is kind of a slightly hyperatic piston, offering a good compromise between a simple cast piston and a hyperatic piston. If I understand correctly.

What 4032 alloy piston options are there for use with long rods?

As for cam, besides stock 99 cam, I also like Mopar Purple cam.

Does anyone know what model years of 4L engine can use a Purple cam?

You can use an earlier cam you just need the timing cover, chain and bolt with the cam bolt with the spring loaded pin which is what most do.Not many options other than a custom cam built on the stock core so you can use the cam retainer.

wjtom wrote:You can use an earlier cam you just need the timing cover, chain and bolt with the cam bolt with the spring loaded pin which is what most do.Not many options other than a custom cam built on the stock core so you can use the cam retainer.

What i meant was you will need to switch to an earlier style then there are alot of options.But if you want to keep the cam retainer that will limit you to custom grinds on a stock core.

wjtom wrote:

wjtom wrote:You can use an earlier cam you just need the timing cover, chain and bolt with the cam bolt with the spring loaded pin which is what most do.Not many options other than a custom cam built on the stock core so you can use the cam retainer.

What i meant was you will need to switch to an earlier style then there are alot of options.But if you want to keep the cam retainer that will limit you to custom grinds on a stock core.

So you're saying a purple cam won't fit an early 99 engine, unless I change valve cover and timing chain?

RenoF250 wrote: They don't, United Engine and Machine own KB, Silv-O-Lite, and Icon:
https://www.uempistons.com/

Your kidding, right? Maybe I should have said the same company that makes the KB pistons makes the silvolites.

I have the IC944s in holes that are 0.0035" over and I do not hear them when cold.

Then they haven't been cold enough or you can't hear well.

They supposedly used an alloy that expands about the same as a hyper so they do not have the noise of a regular forged.

They are made of 4032 and it does not expand in the same manner as the hypers (or lack there of)... if it they did you wouldn't need .0035" clearance.

charley3 wrote:How about 4032 alloy pistons with long rods?

The KB 944s are 4032 forged pistons. Same deal.

I read at Wiki that 4032 alloy is for performance hyperatic pistions that have 11% silicon in them,

4032 typically has 11% silicon content. Hypereutectic is around 16-19%. 4032 is not hypereutectic. In simple terms Hypereutectic meand more silicon above the eutetic point.

So the 4032 alloy is kind of a slightly hyperatic piston,

NO.

What 4032 alloy piston options are there for use with long rods?

KB 944/ 945 or any other custom piston using the 4032 alloy.

I thought (from Wiki) that 4032 pistons are cast, but in this thread I just learned some 4032 are forged.

Am I understanding correctly that some brands of 4032 are cast, and some 4032 are forged?

wjtom wrote:You can use an earlier cam you just need the timing cover,

Not all of those covers are lacking the dimple.

charley3 wrote:Am I understanding correctly that some brands of 4032 are cast, and some 4032 are forged?

All 4032 alloy pistons are forged.