Chip Tuned

Robmw wrote: ...Ivan's had 165k...

That was a misprint. It should have read 156k.

Playing with engines in the 150k miles plus bracket is really a waste of time in my opinon.  You have already lost wads of power due to poor compression with worn rings and bores.  Drive ability may have improved with a chip which is always great news but the power will never be there.

Depends what you are looking for really.  I'm still modifying my M635 which is pushing probably way over 300bhp now but it has cost loads of money.  Been down the cam route which completely changes the engine characteristics.  Really really addictive above 4500rpm to redline at 7000 but the loss in low down torque is an irratation on the road.  Mines heading towards a track car now but that's my choice.

Save your money and invest in some desent oil to prevent bombing of the engine or....... get the chip get the cam get the cold air induction then rip that engine apart, new light weight pistons, rebore, port and polish etc etc.  It's great fun, but add in the brake upgrade, uprated  and fully adjustable suspension, proper wheels and tyres and things start to become a bit of a finanical joke.  Just don't tell the misses.

PS  Horsetan - fitted that M6 suspension yet!!!!!!

Afterthought.

M635 - 1986

Je Pistons with Total Seal rings, 2*272 schrick cams,ported and polished head,bespoke k&n cone filter,fully adjustable front and rear suspension,dinan stage 3 suspension set up, e34 al control arms, goodrige hoses, red stuff all round, 8*18 BMW alloys, e28 M5 25mm front ARB, dinan rear 19mm arb, 750 bush mod, UUC short shift, 25mm 750 brake master cylinder, Sparco front strut, BMW rear strut, K-mac front strut mounts (on route) - Scottieturbos MAF conversion (next year)

See- told you it becomes a joke!   But fun.

Have fun.

Pipes wrote: Cheers for that Ian you've made me and my car feel insignificant.

Ah ha.  85k miles with history (ish) and new head.  Good starting point.

Learning fast I see as well.  Any consolation - mines all self taught over 20 years of tinkering about.  You are in safe hands here on this board.  There is loads of experience and loads of mods to do.  Just take your time as your budget allows, do the sensible things first then build on that.

Gaydon would be a good meet up

Ian

-back to back dyno testing and temperature correction are required for accurate comparisons. I'm not sure the latter was carried out properly on the dyno day, so comparisons with DIN or SAE standards (or any previous results, even from the same dyno) are not easy.

The dyno was an inertial type with a relatively light roller; this tends to accentuate auto vs manual differences.

see; http://bigcoupe.com/phpBB2/viewtopic.php?t=2283&start=45

for further comments. I don't think they even used a pickup for measuring engine rpm, so they just went on the tacho reading (very dodgy). So the dyno day was all good fun but not a lot more. 

My own 150000 miler is a little worn, no doubt. But the compression is still absolutely fine, and it uses very little oil. Also note that the engine has probably turned fewer times than (say) an M635CSi at 110000 miles, because of the very tall gearing. Is tuning a waste of time? Well it would have been when I first got the car because about half of the senders that instruct the fuel injection system were faulty. Now they are OK and tuning is no longer a waste of time. Note that Dave's intergalactic highline (chipped) showed healthy power even with a slightly noisy bottom end.

My own car goes 0-60 (indicated, so more like 0~55 truly) in 7.0 seconds dead, not too bad for an auto allegedly ~15bhp down on stock, eh?

cheers