Lykins Motorsports, Basic Engine Assembly Series - Calculating Piston Compression Heights

[@chrishunter8114]

Excellent video, thanks!

[@darrenh.3514]

Made complete sense! Thats why I called you during my last build and will again when the FE goes on the stand. My 351C rips, great cam and advise thanks!

[@Bobby4v]

I'm really enjoying all these "how to" videos! Thanks!

[@1murder99]

I like the way you think brother.

[@patrickwendling6759]

Cool.. Thank you

[@jesslackey1003]

Brent this is a great video, the math is super kool. thanks for taking the time to show the math

[@mre7283]

Never seen anyone else do this type of videos. Please keep it up! Thanks

[@broncobros2022]

We all love the video’s when we see one of your engines make big power on the dyno, but this was one of the best videos I’ve seen yet. I have learned more about building an engine from watching your videos than anyplace else. Thank you and please keep it up.

[@strokermaverick]

Now, you're just showing off! 😃 Great job, sir!

[@krtacct]

Way to keep it simple and easily understandable. I think you missed your calling to be a professor.

[@donveterano3944]

Engine maths at its finest. Have a nice weekend!

[@alanhickey7433]

Thanks Brent, great info as always

[@jeffschwartz5199]

Cool 😎!

[@gregoryb7485]

The question I asked about when you choose to use a flat tappet cam was honest, I’m sure there are reasons. Thanks

[@lykinsmotorsports]

If it's a solid lifter block only, then I can't use a hydraulic cam. When it comes down to a solid flat tappet or a solid roller on a street car that will get driven a lot, I'm going to pick the solid flat tappet. Solid rollers that are not pressure fed just don't last that long in a vehicle that's driven a lot. Otherwise, a hydraulic roller is usually the best choice for a street engine that sees up to 6500-ish rpm.

[@gregoryb7485]

Thank you

[@dansanford7747]

Thank you Brent for your different ideas and way to do things I really enjoy that I wanted to ask you about a 331 stroker I haven’t heard you talk much about those if you would comment sometime on a build like that it seems to me that a 347 is going a bit much on the stroke I’d like to have your opinion thank you

[@lykinsmotorsports]

There is no reason to go with a 331. More stroke equals more displacement which equals more power.

[@jackwells1452]

Very Very informative, thank you Brent,,, there are trolls everywhere, screw em

[@ronniemiller280]

That was very interesting Thank you

[@kevineguia8721]

Will that pistón handle a twisted wedge head with a 600 lift cam?

[@jamesford2942]

I'm working on a bit of a crazy project. I have been looking at what combination of parts will work. I don't really care who the OEM was or what engine it came from as long as it will fit and do the job. Often you can keep from having to reinvent the wheel if you are willing to throw your box away. Now for the crazy build, I am putting an Australian cast iron closed chamber 2V Cleveland head on a Jeep 2.5 4 cylinder. Water ports need to be delt with a the head bolt holes moved inboard a total of 3/8". I am probably going to stroke it and find an off the shelf piston that will work with this combo of Ford, Chrysler and AMC parts. Maybe we can get all the OEM's parts to play together.

[@Turbo4Joe363]

I understand about factory tolerances....but do you 'take what the block' gives you? i.e. not machining a block that has good tolerances. Also, do you use head gasket thickness to set your quench?

[@lykinsmotorsports]

I never use a block as it is. They're all out of whack, even brand spankin new aftermarket blocks. You'd be surprised.

[@jeffjones4040]

Do you run custom pistons in everything? What is the typical cost and time to get over an off the shelf piston? I need lower compression for pump gas and it seems the off of the shelf pistons are a big dish. I would prefer a dish that matches the head chamber.

[@lykinsmotorsports]

95% of the time, I'm ordering custom pistons for builds. It's a rare situation where I don't have to.

[@samuelfreeman9518]

Question. So I have a 352FE and it needs a rebuild. All aftermarket 352 pistons, standard or overbored are way down in the hole. Is there a piston out there that would work? If my memory is correct a 390 rod and 351M piston gets kinda close but, good luck finding 351M pistons and quit a bit would have to be cut off the piston because it would be way out of the hole. Next step is to just throw my hands up and build a 390 and get 10mpg.

[@nova467spanker]

Lykins Motorsports Hi Brent. You said you like to use a 6" - 6.400" rod in Clevelands. I have the Eagle 5.78 H-Beams in my 359c. What benefits would the longer rods be in the Cleveland? I figured since the Cleveland has such thin cylinder walls the shorter rod would keep less load on the cylinders. Am I correct?

[@lykinsmotorsports]

I've never seen where rod length puts any loading on the cylinder walls. That seems to be a leftover wives tale from years and years ago. If that were the case, then a 408C would be horrible, but you know how many of those are running around. Generally, I see the longer rods making more torque. With a stock Cleveland rod journal diameter, you're basically stuck with a 5.780" though. The other sizes are SBC rod journals.

[@MaciusSzwed]

Which crankshaft do you use? Regrinding the stock one?

[@lykinsmotorsports]

Yes

[@jimm8264]

Brent do you worry about L/R ratio with a longer / shorter rod length? What is your opinion of it?

[@lykinsmotorsports]

I put zero thought into rod/stroke ratios. The rod's job is to connect the piston to the crankshaft.