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4.6L Stroker, Help me build it please!

RE: FrankZ
Whats CC the head? I know to many CCs and the newest way I havent heard of yet.

Check yes to everything else. Cam is the ever so popular Crane 260/272.

I have no clue how many times the head bolts have been torqued down. Im going with more then twice seeing the head looks really clean when torn down, and Id rather be safe then Blown Head Gasket
 
XJoshua said:
Whats CC the head?
Click to expand...
It means that each dome section of the head is measured to deternine the actuall volume. The volume of each should be identical. Take alook at the MADXJ spread sheet and you'll notice that the volume can be changed to reflect the mesaured volume. This will have a direct effect on your static compression ratio.

CC = Cubic Centimeters

LINKY TIME!!

http://www.maxracesoftware.com/cc'ing__heads.htm
 
Can I get my valve tips filled down in order to make them flush with the retainer? See post #79 for picture.
 
Piston decision time... Im stuck between two choices, and one has more cc, and the other has less. So its a matter of knowing which one can easily be cc'd without losing stength.

STL-677CP30 with a dish volume of 17.5 then cc'd to 22.
or
H802CP30 with a dish volume of 15.8 then cc'd to 22.

Im sure I have more question I just cant remember any, but this is the most important right now since it will allow me to get the damn engine into the shop and then start building.
 
UEM-2229 on Summit is called UEM-2229030 which I believe is the same since all their pistons end with 30. Also they have UEM-2229C030 which Im guessing is Coated and thats the one I should get. Does anyone have the Pin Height measurment of these?
 
As fare as rods shot peened......you will have to have the large end of the rod re sized any way with the hi strength rod bolts, any way.

you are grinding down the casting seam any way might as well have it Dun also

it seam like a odd possess but it will strengthen the rod where the rod bolts can't!
It's not necessary but i would do it!;)




Flash.
 
Ok noob here I have the 4.2l crank and rods and a 4.0l block and head I was under the impression that I reused the 4.0l pistons with the 4.2l crank and rods in the 4.0l block. Very good info on everything but the pistons.

I need to be taught that are Sealed Power pistons are they after market or factory?
What years and or what is the Renix brand?

The crazy think about this is all the Honda motors that I have put together we never worry about quench and we throw all sorts of head, block, crank, rod, and piston combos together and then make 400+hp and drive the hell out of them on the street and the track. The thing we look at more then any thing would be compression and Rod / stroke ratio but I think that is more of an issue with how high we rev the motors.
 
Last edited:
XJtoy said:
The crazy think about this is all the Honda motors that I have put together we never worry about quench and we throw all sorts of head, block, crank, rod, and piston combos together and then make 400+hp and drive the hell out of them on the street and the track. The thing we look at more then any thing would be compression and Rod / stroke ratio but I think that is more of an issue with how high we rev the motors.
Click to expand...

I was concerned about my quench when I installed the motor, but I've found my stroker runs perfect on mid grade fuel. My quench is .095", which is considerable more than the desired .070" max quench.

Joshua-
Are you sure you want to go with the Crane cam? Numerous people have had problems with Crane cams. I have the Crane 753905 cam in my stroker, and it's running perfect with 6k miles. Had I known about the problems, I would have gone with a different cam. Read this thread:http://www.jeepsunlimited.com/forums/showthread.php?t=787667
 
So what pistons do I need to run I do a search and come up with nothing anybody have some info for me a link or something.
 
The whole 260/272 Crane Cam failure thread seems to 50/50. What would cause a crane cam to fail, people not properly breaking in the motor, building it wrong, or just abussing their motors?

XJToy-
We use 4.0 Pistons, but they are oversized. Go to summitracing.com and in the search type "Jeep 4.0 Pistons" and it will list the oversizes that you can choose and plug into the calulator. Also in a previous post sonic testing is recommended for motors being bored .040" or more. If you only bore .030" you are safe and can avoid the sonic testing.
 
Any number of things can lead to cam failure, but I'd venture a guess that improper break-in is the leading cause.

Let's face facts, after building a stroker it's very difficult not to jump in and see what she'll do. I doubt that anyone will step forward and admit that they didn't follow proper engine break-in procedures, apply the proper assembly lube/grease, installed old lifters, etc. It's easier to blame the part than it is to accept the blame yourself.

I'm not saying that's the case with all of the Crane cam failures, but ya gotta wonder.....
 
I think Crane uses materials that don't have the necessary hardness to endure the stress of heavy duty valve springs. I'm using the stock valve springs to help reduce the chance of a lifter/cam problem. This does reduce my redline to about 4800 rpm's, but I'll happily sacrifice some rpm's for longevity and reliability. I'm also using Lucas oil stabilizer in every oil change which I am a strong believer in.
 
Frank-
I find it hard to believe that several people are having problems with the same camshaft because of something other than a product defect. The camshafts are wearing out anywhere between 5k and 34k miles. Improper breakin would cause a cam to wear out within the forst 100 or so miles. One issue I've read was the crane cam has lobes that are 20-30% narrower than the stock camshaft. This would increase pressure on both the cam and lifters, thus contributing to the accelerated wear. Another issue is oil these days does not have the zinc and phosphorus additives that it used to. They are anti-wear additives that are somewhat necessary for a flat tappet engine.
 
What would you suggest as a alternative to Crane Cams? Comp Cams?

My break in process is for first 500miles stay under 55MPH, and under 3200RPMs. After 500miles start revving a little higher for another 500miles to prevent a lip from forming at the top of the cyclinder bore. After that she's free to feel the full force of my foot :D
 
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