Crank Tollerance

[Grats]

Just checking over my competition engine, what tolerance would you expect to see in the main bearings to crank?

Thanks

 

[JamesBryan]

0.040-0.075mm according to the specs i have.

@NorthloopCup has the spec sheet i think.

EDIT:

 

[Grats]

Thanks, I’m just at the upper limit, just under 3 thousands of inch in old money.

 

[Robbie Corbett]

Did R3 cars have a different oil pump?

 

[JamesBryan]

Thanks, I’m just at the upper limit, just under 3 thousands of inch in old money.

Yeah 3 thou is 0.076?

Thrust clearance on that list is wrong by the way, the upper limit should be 0.023mm not 0.23mm according to my Renault pdf.

 

[JamesBryan]

Did R3 cars have a different oil pump?

Pass.

Probably not different, just modified maybe.

 

[PhillipM]

Yeah 3 thou is 0.076?

Thrust clearance on that list is wrong by the way, the upper limit should be 0.023mm not 0.23mm according to my Renault pdf.

That seems incredibly tight for thrust washer clearance if it is, especially on this size 4 cylinder. Most stuff is 0.1-0.4mm in this displacement?
0.023 wouldn't even leave enough for thermal expansion?

 

[JamesBryan]

That seems incredibly tight for thrust washer clearance if it is, especially on this size 4 cylinder. Most stuff is 0.1-0.4mm in this displacement?
0.023 wouldn't even leave enough for thermal expansion?

Yeah probably right, the pdf must be wrong.

 

[Robbie Corbett]

That seems incredibly tight for thrust washer clearance if it is, especially on this size 4 cylinder. Most stuff is 0.1-0.4mm in this displacement?
0.023 wouldn't even leave enough for thermal expansion?

0.4 would be a bit lose, Ford Zetec is 0.09 - 0.260 but agree 0.023 looks like an error - perhaps it was supposed to be 0.07 - 0.230 which is more inline with the Zetec specs.

Wonder if anyone has built to 0.023 in the past and wondered why the crank didn't turn 🤦‍♂️

*Edit sorry saw James said it was a typo.

 

[NorthloopCup]

Did R3 cars have a different oil pump?

Nope. R3 generally had better oil pressure because of a couple other areas were different to the 1*2 f4r.

I used to modify the oil pumps for all the engine builds I’ve done, but it wasn’t just a case of shimming the oprv.

 

[Robbie Corbett]

Nope. R3 generally had better oil pressure because of a couple other areas were different to the 1*2 f4r.

I used to modify the oil pumps for all the engine builds I’ve done, but it wasn’t just a case of shimming the oprv.

For the OP I'm not sure I would target R3/top of R3 clearances without knowing (from someone or just experience) that oil pressure when hot etc. will be ok.

 

[NorthloopCup]

For the OP I'm not sure I would target R3/top of R3 clearances without knowing (from someone or just experience) that oil pressure when hot etc. will be ok.

If it’s a 1*2 f4r I would imagine the oil pressure will be similar to the pressure of pissing into a bucket. They’re horrific and it took a lot of working out to understand why they’re so poor. It’s not just one thing either, it’s a combination.

 

[Robbie Corbett]

will be similar to the pressure of pissing into a bucket.

@Tubbs Vice Northloop is mugging your ma off again.

 

[Grats]

Thanks for everyone’s comments.

Is there a difference in oil pressure / oil way design between the 1*2 and the 197 engines?

I’m running a 197 unit in my 182, never ran an oil pressure gauge just a higher rated warning switch - never had any issues in 8 years of rallying - just been lucky?

Thanks

 

[NorthloopCup]

Thanks for everyone’s comments.

Is there a difference in oil pressure / oil way design between the 1*2 and the 197 engines?

I’m running a 197 unit in my 182, never ran an oil pressure gauge just a higher rated warning switch - never had any issues in 8 years of rallying - just been lucky?

Thanks

Yes quite a few differences in the 197 engine to the 1*2.

 

[Grats]

Thanks very - so I assume better oil pressure and that a tolerance of 0.075 is ok for a competition engine. Is the 197 closer to a R3 spec as such the tolerance is mid range?