Any downside to doing a big bore and stroker to gain additional CI? Piston slap, etc.
Stroking the Terminator
- Thread starter POPPAJ
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Nobody knows? How about a guess.
Wouldn't have responded til you said "guess" so I'll take a shot at it. LOL
Big bore is with either a Teksid or Boss 5.0 block. Romeo should not be taken out past .020". Boss 5.0 better basis for 3.700" bore and un-shrouds the valves.
Only down side is less gasket width between the bores but it's not too bad.
Stroking this engine is somewhat hoakey but is done quite often but leaves very little piston in the bore at BDC. The 3.75 stroke is very long and not as rev happy, requires cutting into the oil ring groove land so there is no support there and leaving the ring hanging in the breeze and steeper rod angle which pushes the piston more into the bore. I would take a pass on this option.
Thanks! Just the info I was looking for. I would be using the Boss 5.0 block. At this point I'll give further thought about the stroker for the time being.
Surprised on only one response. Guess I should have started a "What's the best oil" thread.
Surprised on only one response. Guess I should have started a "What's the best oil" thread.
No problem
Try using the search option if your not getting the info you need. I counted 50 hits on the word "Stroker" alone.
Search didn't do much good. No opinions that I could find. You're info is what I was looking for. Basically, what's the down side, durability, etc. Like other opinions though. Surely someone has experience with a stroker in a daily driver.
what are your goals?
Ive talked to several engine builders over the years and they all say do a 5.0 block with no stroker kit.
Ironically, they all said the 'useful' life of a stroked engine that gets 'used properly' is in the neighborhood of 50,000 miles
Ironically, they all said the 'useful' life of a stroked engine that gets 'used properly' is in the neighborhood of 50,000 miles
The God Part is the beginning of my last name.
Yep that is the same thing I was told. I too would advise going with the 5.0 block over strokeing it. I had mine built 5 years before the 5.0 block came out or that is what I would of done.
:nono:
The OP asked if there are any downsides to stroking this engine which was more or less dismissed here.
On an engine with precious little skirt left in the bore needed to hold the piston true in the cylinder at BDC pulling it out of the hole by an additional .200" will only make matters worse. Now add more PWC and a lack of full oil ring support, less wrist pin length/shorter pin bore, increased rod angles and higher piston speeds and you have a piston that will rock more then if the stroke was left alone in the bore as it transitions at BDC. This engine won't like revs as much as a stock stroke mill. That is not an opinion. I think most people will draw their own conclusions by what has been stated here.
Some people may feel making all these compromises are justified to squeeze a few more cubes out of the engine which is fine if one understand the downsides to stroking a 4.6. But it's the wrong direction to go if one places a higher priority on durability or longevity over total engine output. The cylinder pressures this engine can generate are massive and this mod pushes all the needles in the wrong direction. I don't think any engine builder worth his salt will stick his or her neck out and publicly disagrees with what has been stated here. If they do please speak-up and tell us why this isn't so.
I did not say I didn't agree but this has been brought up many times so I just made it short and sweet and there are always people that will disagree with it. Also did you see where I said if you wanted extra cubes to go with the Boss 5.0 block.
Thanks everyone! I won't be doing the stroker, just the 5.0 block. Although I don't beat on my cars and rarely hit the strip I don't want to lose the reliability as many have mentioned.
i like the title of your thread... LOL!
I like your avatar ......
on a topical note. Does the 5.0 Block accept the 4.6 Guts ? or will there be similar issues to a stroker with clearances and angles being slightly out of wack. ? Do you just use a slightly longer rod ?
EDIT: NVM Im slow... the Bore is bigger.
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God Stang
You should, more then most, know the dangers of making "short & sweet" statement when it comes to technical matters because if the reader gets the wrong impression it may cost them dearly. There are quite a few people who read these posts who are just learning about the details of building an engine or whatever the topic at hand is. We address one persons comments but many people end up reading them and suddenly it’s got them thinking in whole new direction (Mission Accomplished!). That's what makes this site so great.
You've read enough of my post all these years to know when I see something that either omits details or is misleading I will chime in often to their dismay but I try to do it in a respectful manner. If I overlook details I expect someone to correct me because I don't want to be walking around with the wrong impression and possibly leading others down the same path. I know you are a guy who is not intimidated breaking down a motor and modding the hell out of it. That is something to be respected by all considering the power levels we are playing with and the potential for something to go catastrophically wrong. God knows I've made my share of mistakes but sometimes you tend to learn more from then if everything went as planned but that gets expensive :nonono:
Yea, the 24 added cubes was a big motivation for me getting the Boss block but that is because of the larger bore which this engine sorely needs. Had it been only obtainable by stroking I would have left it at 4.6 which is still capable of making more power then the chassis can handle. The overall improvement in the block design (and there are many) was a big factor as well. Having built many types of engines over the years the Ford mod motors are about as impressive as they come.
Russ :beer:
There are some advantages and disadvantages to both.
I like how we have the option of either boring or stroking to reach approx 5.0 liters. Of course, you can do both.
I've noticed that there are a lot of different stroker cranks available for the 4.6, but not much information on the differences.
There's the Lunati MOD3800 Ford Modular 4.6L Stroker Crankshaft 3.800 Stroke with 6.00 Rod Length
There's an offset ground crank with a 3.750" with 5.950" Rod Length
I couldn't find much info on the difference in displacement between these two different stroker cranks.
It would be neat to see a big bore vs. stroker comparison in one of the magazines, holding all else constant to see the torque curve of the stroker vs. the unshrouding of the valves for the big bore. Then, of course, doing both.
I like how we have the option of either boring or stroking to reach approx 5.0 liters. Of course, you can do both.
I've noticed that there are a lot of different stroker cranks available for the 4.6, but not much information on the differences.
There's the Lunati MOD3800 Ford Modular 4.6L Stroker Crankshaft 3.800 Stroke with 6.00 Rod Length
There's an offset ground crank with a 3.750" with 5.950" Rod Length
I couldn't find much info on the difference in displacement between these two different stroker cranks.
It would be neat to see a big bore vs. stroker comparison in one of the magazines, holding all else constant to see the torque curve of the stroker vs. the unshrouding of the valves for the big bore. Then, of course, doing both.
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