engine rebuilding to spec

[BlitZ]

Hi all,


I am wondering if most rebuilders (workshops) torque all engine internals to spec in a rebuild or do they just guesstimate...... cause i cant imagine them find a spec sheet for each rebuild...

and with an engine rebuild..........
what component is the most likily cause of some of the badly built engines out there.. (no power- drinking oil?)
(eg. honing, seal installment, torque (screwing seals) etc)


thanks in advance,
noobie dan

[Weq]

there is a difference between a good rebuilder and a bad rebuilder and a generic rebuilder. All of the above are apparent. Drinking oil would point to ring clearance, or value/guide issues.

[steve]

I would say 99% of engine builders torque to spec, however some might torque to bolt spec and not manufactures spec, which can be different.

[ProECU]

Top engine builders also measure rod bolt stretch.

[steve]

How and when do they measure this? On the old bolts when they are removed?

Top engine builders also measure rod bolt stretch.

[Slow96GSR]

We have books with all the cars and what each and every bolt should be set to. This is for OEM parts and thru the manufactures. An aftermarket part will come with a data/install manual and tell us. If we don't know what to torque it to we call the manufacture. No true builder will slap a motor together and just guess, that would be your DIY type builder that has never done this type of work and doesn't know what he or she is doing. I not only torque it once, I go back 2-3 times and check to make sure. If you think your builder did an improper build, check it yourself or find a new builder. If you don't feel safe in your car, you most likely won't drive it to its fullest capability.

If you all are unsure of your builders there, there are plenty of good builders here in the U.S. If you are worried about shipping think about how much a new block costs if you throw a rod because the builder forgot to torque it. Fedex offers great deals and I know our shop can help you out with better deals on parts to even out the price after shipping.

[spardikis]

How and when do they measure this? On the old bolts when they are removed?

if you buy after market head bolts for instance, they should let u know how much they stretch (when reving hard, hot - cold etc) so the builder can take this into account when torqueing down the head.

[steve]

if you buy after market head bolts for instance, they should let u know how much they stretch (when reving hard, hot - cold etc) so the builder can take this into account when torqueing down the head.

Wouldn't the bolt manufacturer account for this when they give you the torque spec for the bolt? to take all the guess work out?

[e240]

they may torque to spec, but they're torque wrench may be out of calibration anyway....LOL