....by Dinan. Mainly because the US-spec cars were down on power compared to the Euro ones, so all they were doing was playing catch-up in most cases.

If it's replaceable chips you're looking at, then Superchips, BBR or Jayson (ChippedUK) are usually the way to go, but really only post-1985/6 cars can be dealt with. "Highlines" are better suited to this treatment.

Jayson reckons he can re-programme or remap some of the earlier cars (Motronic 2.1 ECUs, normally coded "011" by Bosch), but the chip itself cannot be taken out and replaced by another because Bosch hard-wired these early ones in.

Re-mapping has had some UK coverage already, mainly from owners of M635CSis (all years) who have discovered themselves to be down on power over the years..... Also, the "Highline" edition of the M635CSi sometimes didn't leave the factory with the full 286hp....

Jayson - is there anything worth doing to mine?

1981 635csi

Webdunk wrote: ....Gains of up to 11bhp can be attained.....

I was quoted "up to 8 hp" for Motronic 2.1....

Pipes wrote: 11hp is it worth the money?

Dunno, it depends on how much Jayson charges you in the event of you booking in to be dealt with by him. At a really wild guess, I'd expect it to be somewhere between £150 and £350 for the work, though...

Would the gains be that noticeable?

If you think (or had it confirmed) that your car is way down on power, then you've probably got more chance of being aware of any improvements. I'm not sure I would notice the full eight extra bhp in my case. I'd spend the money on new tyres and the upgrade to M635CSi suspension first, and see how effective that is on putting the existing power to the floor.

These older cars dont see much true feel of extra power but the smoother delivery of power is a nice touch.

I charge lower for this work even though the job is harder because i feel the gains simply dont justify a price tag of £300+

Maybe if you had a 530d then the gains in my opnion are worth as much as you care to pay and are vastly different to original but on these cars the gains are less prominent so the price reflects this.

I did dave`s who went on the dyno day and from what i gathered, his gave very good results?

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.

ian M635UK wrote: ....PS  Horsetan - fitted that M6 suspension yet!!!!!!

All in good time, Ian, all in good time . I've got the MoT in a couple of weeks, so let's see whether my local station spots the almost bald 225/60/15s

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

His work on the car makes everyone feel insignificant

.....I didn't know anything about cars or engines a year ago.....

Ah, you're in very very good company

..... I (or somebody that knows what they're doing)....

Nobody knows what they're doing where a Six is concerned! That's the fun of it.....I think.....errm.....

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

Robmw wrote:   - really impressed on the day an early Red 635 with a Fritz manifold ...it sounded terrific. Rob

ah yes, that'd be my car. In fact this is a misquote though (even though this went into Total BMW too)- my car has a full Fritz's system, manifold, down pipes, both boxes, one-off clamps etc all in stainless, lovely...

Best of all its not too noisy with the windows shut; I drive my aged mother around in it sometimes and she doesn't feel embarrassed until we have the windows open and I clog it in a built-up area; then she does... oh yes...

cheers

Brucey, is yours manual? It seemed that the manual cars faired better on the rollers power wise..?

Also, from the article it seems so much better to fit a decent manifold/system and a proper cold air feed if you're re chipping - together they seem to do quite a lot for the overall power.

It is interesting to see just what these cars make at this age. I noticed James' car making 222hp with (am I right?) a chip and manifold and custom cold air feed. So have these mods only released 4hp (from 218) or could the figures have been higher with a newer motor..

?

-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 - 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

Brucey wrote: .....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?

There's hope for us older ones, then