running in a rebuilt engine

[Rz]

a more agressive tune for race fuel , run on plain jane shit from the pump .... it happens all the time dazza

[piss98]

Diesel?

Must be some pretty shitty fuel to blow up an engine

Nah it was the tram oil.

[phee]

unleaded

[Babalouie]

I'm going to have the same issue one teh RX7 is back in one piece.

Luckily hills and highways are within easy reach.

I was told by my builder that with rotaries, load wasn't really an issue and that cruising along at constant load on the freeway was actually a good way to do it.

Edit: btw I used the Motoman technique for my MX5 engine and it's great, 20,000kms later still has the same compression and uses no oil.

[Cplus]

the tune on the computer is fine. I was the one who fucked it with the wrong fuel.

assumption is the mother of all fuckups.

you really want to risk it?

the new build will have a slightly different CR for a start.....

[dazza]

When mine blew up on the dyno (lean out in #3 cylinder) we just assumed it was my dodgy wiring job or a computer problem with the injector driver

Wasn't until I broke another piston did I get the injectors checked for them to tell me it was just a little bit of silicone on the injector plug

[blimpyboy]

how many people buy new cars from the factory and go through religous type run in procedures?

I believe that's the apprentice's job :D

[IMOA]

Be very cautious of that - It's intended for racing motorbikes, not road car engines.

Interestingly I've got a mate who used to race bikes and during his engineering degree did a lot of testing of different run in techniques and he couldn't disagree more with motormans theories. What he found was the "thrash the crap out of it" run in left a lot of "peaks and troughs" in the rings/bore which bedded them in nicely but over time those peaks would give way and the engine would lose compression faster than using the old fashioned way of running in. Not an issue if you are rebuilding regularly but not the ideal way of doing things for the average punter.

[Billzilla]

Interestingly I've got a mate who used to race bikes and during his engineering degree did a lot of testing of different run in techniques and he couldn't disagree more with motormans theories. What he found was the "thrash the crap out of it" run in left a lot of "peaks and troughs" in the rings/bore which bedded them in nicely but over time those peaks would give way and the engine would lose compression faster than using the old fashioned way of running in. Not an issue if you are rebuilding regularly but not the ideal way of doing things for the average punter.

Pretty much exactly what a mate of mine from Cosworth said.
If you want the engine to last, take it easy.

[TK]

Bed the cam in at 2000 - 2500 rpm for the first 20 mins, giving the throttle the occasional blip to get the oil moving, after the cam bed in change the oil & filter to get rid of the crud.
Drive normally (unless u usually drive like a pissed 17 year old) for 500 k's, don't be afraid to nail it occasionally (gets the rings working & helps bed in) but avoid big revs, change oil & filter again.
One of the worst things u can do to a fresh engine is baby it to much, the bores will glaze & it'll burn oil & have too much blowby.
Do not let a fresh engine idle for extended periods.
Do not load up engine too much, if u'r going up a hill don't lug it in a high gear, go back a gear.
If it's got moly rings & torque plated bores 500k's is plenty of run in, un-torque plated bores can take up to 1000k's to bed in properly, plain iron rings can take even longer.
Change oil again at 1000k's & the every 5000k's after that.
Have fun!

TK

[AlexinPerth]

Wait until Dale gets there.

Alex.

[Bob Saget]

Another vote for waiting for Dale.

[dazza]

Whoever dale is he sounds like he knows what he is doing

Dale Dale he's our man if he can't do it phee will have to...

Or is this the obligitory wait for a man response?

[SLO78U]

Be thankful you don't have to run pre-mix like I will have to

pre-mix rocks !!! i love it. takes 5 min more at the bouser but it means no dirty engine oil is getting pumped through the rotors !!!

Phee - check with dale. did he build it ?? he'll know the best way !!! hell it's his job !!!

[10sec rx7]

I told Phee last night 500km minimium, by then the rings should be done, then ill do a hour of load on the dyno before giving it a hard time just to make sure its right!