£600 for short block refurb - Reasonable?

[omi]

Hi folks,

I'm building an E30 318iS Turbo, running 8:1 compression. Found the pistons (JE, gapless rings, £450 delivered) so I'm looking for somewhere to rebuild the bottom end.

I've been quoted circa £600 by a local firm to strip the short block, 1mm overbore, balance the rotating mass, replace all bearings, clean through the channels and crankcase and reassemble using the new pistons.

Does this sound reasonable?

[busa_rush]

Sounds reasonable but do they know what they are talking about ? Have they done a conversion like this before ? I'd want to find somebody who has done this before, there's more to a conversion like this than just fitting the pistons.

[v8 racing]

sounds very reasonable realy

[Omi]

It's just a bottom end rebuild... I'm sure they've done that before.

[busa_rush]

Omi said:

It's just a bottom end rebuild... I'm sure they've done that before.

It's not, for example what piston to bore clearance do you need ? It's not the same for a turbo engine as it is for a long life, cool running n/a engine. What clearance is needed on the bearings ? This may be different too. If you find somebody who has done this before they will know, a local garage won't have a clue. If you don't get these things right, the engine won't last very long.

[Boosted Ls1]

It's very reasonable. They have to check bore clearances, check for any f*** ups and assemble it for you. Then wait for any complaints because it might not work the way you intended. Are you expecting them to file fit the Total Seal rings and champher the edges? Are they even aware of this? If not, I'll do it lol

Boosted.

[Omi]

Sorry Busa, didn't mean to sound arsey... It's a place that solely does engine workups, 2 man unit, been at it some time... They gave me alot of confidence on the phone just by understanding what I wanted and why, and knew little technical nuances about the crank that most enthusiasts wouldn't have a clue about. (I've been reading an awful lot so I knew!)

I honestly didn't know or think that there may be varying tolerances between NA and FI engines... Can you explain these further of point me to some reference information?

Boosted, you seem to have a good reputation for such things from what I've read on here in Lurk mode. Might be small-fry for you, but would you be interested in the work based on a similar cost?

[Boosted Ls1]

Omi said:

I honestly didn't know or think that there may be varying tolerances between NA and FI engines... Can you explain these further of point me to some reference information? Boosted, you seem to have a good reputation for such things from what I've read on here in Lurk mode. Might be small-fry for you, but would you be interested in the work based on a similar cost?

The tolerences concerned are setting the ring gaps wider for forced induction or to sae recommendations. Making sure the piston crowns are close but not to close to the head and also setting the piston to bore clearance. I've found that you tell the piston manufacturer your bore diameter and they make the piston to suit. You then do a light hone and you're in business. If you ordered the pistons before you checked the bores they could end up being to small, running with to much clearance. Sure, I'd look at it for you. If you PM me a landline number we can chat.

Boosted.

[Busa_Rush]

Omi said:

Sorry Busa, didn't mean to sound arsey...

No problem, no offence taken ! Might be worth having a chat with Boosted, it would be a shame to invest a lot of money in an engine and have it fail for the sae of a bit of measurement etc.