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Who has rebuilt a dirt bike and also a car engine - need advice ?

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So I've rebuilt 4 - 2 strokes, 1 modern racing 4 stroke, Honda ATV's, and my kids air cooled 4 strokes. All went well and are still running fine. I want to rebuild a car 4 cylinder but no nothing of passenger motors. Most recreational motors run all there friction surfaces on replaceable cartridge ball bearings so there is little in the way of checking clearances besides setting valves.

Who has experience with both and can give me a boost of confidence to tear into my car motor and rebuild it. I've had single cyliders rebored but other that that I have not had to use the services of a machine shop. I understand I'll need to rebore the car motor but the rest of the machine shop services are foreign to me.

With passenger car motors what special tools would I need and can most of the assembly be done at home? I'm buying an engine stand and will be borrowing a hoist to pull the motor.

If this is the wrong forum sorry, but there must be some of you out there who have done both and can help me out - thanks!

Edited by LAndrew

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Buy a book. Really as simple as that if you already have experience with motorcycle engines. I built the LT1 in my old camaro a few years back and had a book just for the LT1 and the regular Haynes manual for the car. The books had all the specs I needed and with the internet and messages boards I found answers to any questions I had. I had the machine shop bore and hone the block and install cam bearings. I ordered the full rotating assembly already balanced. It really wasn't too hard, of course you can go crazy with an insane performance build but a simple rebuild is not bad. Honestly the hardest part is getting the damn motor out and all the electronics sorted out, at least with newer cars it is.

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What MotoX178 said. I've on occasion had the whole drivetrain of my Jeep all over the shop, Fri. afternoon(wheelin' Sat. morning). You'll be fine. Take it slow, read, and enjoy the accomplishment. Motorcycle(4-stroke) engines are just smaller. You might even learn how squeeze some more power from it, with little or no extra cost. Remember "There's no replacement for displacement".

Buy a book. Really as simple as that if you already have experience with motorcycle engines. I built the LT1 in my old camaro a few years back and had a book just for the LT1 and the regular Haynes manual for the car. The books had all the specs I needed and with the internet and messages boards I found answers to any questions I had. I had the machine shop bore and hone the block and install cam bearings. I ordered the full rotating assembly already balanced. It really wasn't too hard, of course you can go crazy with an insane performance build but a simple rebuild is not bad. Honestly the hardest part is getting the damn motor out and all the electronics sorted out, at least with newer cars it is.

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Great thanks for the advice, I look forward to getting in there and figuring things out.

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There are a few differences between an automobile motor and a motorcycle motor. Auto motors do not use roller bearings like you are have seen in your motorcycles. The roller bearing are a fool proof way for the manufacture to set clearances and tolerance.

Follow the service manual for the engine and pay close attention to crank and rod journal clearances and end play on the crank. If you DO NOT know how to set clearances and tolerances, or dial in the cam get someone to help you. Nothing worse than putting a motor together and having slop in the crank, spinning a main/rod bearing, or having leaky main seals.

If you do it correctly, the motor will run for another 150k miles. If you slop it together, it will run for a lot less.

My first motor was a 69’ Dodge D100 318V-8. I was all of 19 years old. It went well. My dad ran the truck for 310k miles. Of which the last 170k were on the rebuild!!!! And yes, on that motor, a good friend of my dads taught me how to set the clearances….. It’s not difficult, but some of us learn better by being taught and doing rather than reading a book.

You will do fine.

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Yes check the clearance between the main bearings and crank. Check clearances between the rod bearings and crank. The rest is pretty similar. At least you don't have to split cases

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