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Duracel79 wrote:Mapping will be done by Dave Walker (the mapping king!) on 23rd July. I'll try to remember to take lots of pics and post up the RR readouts

Wow, that'll be a day to remember, I've been a fan of his for ages from his CCC days.

Just a video preview before I do the write-up



Ben

come on then.... how many broke horses?

i know i know, come on ben get on with your write up and stop playing on the PS2

Ok,

some info to keep you going.

Had the car mapped at Emerald by Dave Walker and co. They had four people in total to work on my car for the whole 4 hours we were there. not bad value for money really (~£275).

Final figures can be seen in the crap image below:

197.5 bhp @ 6648 rpm
170.3 lbft @ 5257 rpm



Wasn't totally happy with the figures considering the spec of the engine. But it does drive really nicely.

From running the TB's with Motronic and the AFM the midrange power seems to be the biggest improvement of running Emerald, with a smaller increase up top.

Also had a RR test done at Evolve (Luton) for comparison. Which gave:

209 bhp @ 6200 rpm
195 lbft @ 4500 rpm

Which is very different in the figures but the shape of the graphs is almost identical.
The most useful part of running the car at Evolve was being able to plot a Std Alpina C2 2.7 E30 against my engine.

The Alpina had better torque below 4000 rpm but from then on mine just gets more and more, making 10-15 bhp difference at the top.

I've also been to Santa pod and interloped with some American muscle cars up the strip.

Considering I've never been up the strip before, to record a 14.9 on my first run was pleasing.

Did seven runs in total with a fastest of 14.3 seconds @ 96 mph. But I never made a perfect start

To put this into context: a std E36 M3 Evo will do a 14.5 second quarter.
some images of my car can be found here from 10am to 11.30 am:
http://www.blackettphotography.com/ligh ... =1011-1028

Ok final specs for the engine in my car:

325i block honed to std bore, block machined down by 2mm.
early 325i pistons (9.7:1 CR).
323i conrods (130m) lightened and balanced.
525eta crank (81mm) lightened and balanced.
323i Flywheel lightened and balanced.
std 325i clutch. Balanced with crank/flywheel pulleys etc.
Diesel oil pump (higher capacity from M21 engine)
Winged E30 sump
325i Head, Ports opened out and chambers polished to remove sharp corners.
Steel rockers arms (Newman, needed for 7krpm plus)
Newmwn 300 degree camshaft
Alloy adjustable cam pulley
Dbilas intake manifold, Throttle Bodies and Plenum
BMC Carbon air box CDA-85
320cc Injectors
Emerald ECU using std BMW crank/temp sensors plus a few more
Stack wideband Lambda
Fritz Exhaust manifold
Straight through stainless system 2.25"
Standard E21 323i rad
Mocal Oil Cooler
E30 325i economey 5 speed gearbox
4.1:1 E21 diff with Quaife ATB (Spare 3.45:1 BMW LSD)
215/50/13 Dunlop Formula R tyres

Compression Ratio is about 11:1 which meant we couldn't map on 95 octane fuel, It needed 97 to prevent detonation.


I'm bored of writing now, so will add more later.

Ben

Be interesting to compare my own engine printout with yours. My engine made 196bhp @ 5448rpm with 202 lbs/ft of torque. That was while running a mish-mash of K-jet @ Motronic though so I'm hoping it'll be a bit better with a better, fully Motronic ser-up. I'm going for a Dastek uni chip and live remap. Jason put me in touch with a guy at Castle Coombe circuit and it's a 2 days job costing £400'ish.
Good times at Santa Pod. It looks easy doesn't it? I bet it's not though. Would be fun to see some e36 M3 owners faces when they can't lose the old e21.

Ben, with the spec you`ve listed wont believe its 11:1 mate, if you used the eta early pistons (circa 1981) which is slightly domed and using the 200 head or 731 which has the smaller combustiin chambers you will get the 11:1, using the early 325 (1985-1987) flat top slightly concaved pistons and the 885 head you more likely to run at 8:5 the super eta and the early 325 (chromie) shared the same pistons and same head but with the motronic on the eta resrtcted its performance. No straight forward standard eta engine build is gonna give over 200 bhp in my years of experiance with it you will get 180-190 bhp depending on the condition of the engine e.t.c., the injection/ spark timing/ cam and head works gives the rest to make over 200. alpina used the diesel because its forged and could not afford to destroy their reptation or built cars over cracked cranks on hi gh end driving and they produced 210bhp, over the years ive used the 2.7 with eta cranks and bear in mind being younger at the time back in 1990 i used to thrash em and gave me no problems at all... if you used a 731/200 head and had that ported with larger valves et.c. you will probably hit over 220 bhp easily with the throttlebodies you have on!! your restriction is the head with the combustion chamber end..


J

--ALPINA-- wrote:Ben, with the spec you`ve listed wont believe its 11:1 mate, if you used the eta early pistons (circa 1981) which is slightly domed and using the 200 head or 731 which has the smaller combustiin chambers you will get the 11:1, using the early 325 (1985-1987) flat top slightly concaved pistons and the 885 head you more likely to run at 8:5 the super eta and the early 325 (chromie) shared the same pistons and same head but with the motronic on the eta resrtcted its performance. No straight forward standard eta engine build is gonna give over 200 bhp in my years of experiance with it you will get 180-190 bhp depending on the condition of the engine e.t.c., the injection/ spark timing/ cam and head works gives the rest to make over 200. alpina used the diesel because its forged and could not afford to destroy their reptation or built cars over cracked cranks on hi gh end driving and they produced 210bhp, over the years ive used the 2.7 with eta cranks and bear in mind being younger at the time back in 1990 i used to thrash em and gave me no problems at all... if you used a 731/200 head and had that ported with larger valves et.c. you will probably hit over 220 bhp easily with the throttlebodies you have on!! your restriction is the head with the combustion chamber end..


J

Wrong!!

oooh lol i must have been reading wrong info, ill contact the zone and complain that the info is wrong, so how are you getting 11:1

j

Short answer.

9.7:1 325i pistons which have a high raised crown edge which forms a squish zone.
same combustion chamber size with more stroke gives higher compression ratio

would mean 10.4:1 in the case of a 2.7 with a 47.7cc chamber.

my head has also had 20thou (0.5mm) skimmed off it which reduces the size on the combustion chamber so increases the compression ratio

Therfore mine is getting close to 11:1 or at least 10.95:1 by my calculations and a 45cc chamber.

To be honest this ratio is not what any engine should be built to. Really you should use the dynamic CR which takes into account the camshaft duration.
This uses the swept volume from when the inlet valve closes to top dead centre.

Ben

Duracel79 wrote:Short answer.

9.7:1 325i pistons which have a high raised crown edge which forms a squish zone.
same combustion chamber size with more stroke gives higher compression ratio

would mean 10.4:1 in the case of a 2.7 with a 47.7cc chamber.

my head has also had 20thou (0.5mm) skimmed off it which reduces the size on the combustion chamber so increases the compression ratio

Therfore mine is getting close to 11:1 or at least 10.95:1 by my calculations and a 45cc chamber.

To be honest this ratio is not what any engine should be built to. Really you should use the dynamic CR which takes into account the camshaft duration.
This uses the swept volume from when the inlet valve closes to top dead centre.

Ben

Skimming your head was the purpose to up the CR to get the 11:1? are you using a vernier pulley to time the crank and cam. 11:1 in reality as you says is more than enough but from guys who have been building 2.7 engines for years and are also on the zone have all all said the say being ex bmw technicians, the CR building it the way youve done cannot reach that high, the 885 chamber as you know is larger than the 731/200 and also using the 323i conrods you will have to shave the block and of course skim the head before it goes back using a vernier pulley to get thr timing correct again., i didnt need to skim my block cos ive used the very early eta pistons which takes my piston crown to the top of the block and using an 885 head myself i have a an e30 320 head that i was going to get head work done on and do a head swap to get above 220bhp, from what i know e30 came in 3 different types of pistons, the early were flat top, second were dished (slightly) and the last of the e30s were very dished with deeper cut outs for valves to go into, the second set of pistons in the e30 were similar to alpina c2 2.7 but hat the skirts skimmed cos it would have hit the 2.7 crank webbing causing damage. But if you say you got 11:1 on your engine then well good on ya! people are cutting routes and having cylinder head work done on the e30 320 head and fitting that on their 325`s making it a quicker car e.t.c. but there are different ways to achieve performance and only to use a right cam shaft to the cylinder head you have had work done too..

But its all good, hows the throttlebodies on your car, did you feel any difference at all in the midrange? 0-60? would be good to know what you thought of this kit, my throttleboddies kit is sitting in my garage looking sad LOOL

J

seems alot of effort to me (and cash spent) for another 30 bhp imo. i mean 30 bhp?? isnt that what sort of power a yugo 45 makes?.............. an e30 325i plus a yugo 45?

sod n/a, im deffo guna go the turbo route (if i EVER have any money)!
i want at least an e30 325i plus a mk2 golf 8valve gti sort of power figures.

It's the added torque I'm after although low pressure turbo / SC set-up seems pretty ideal on a 2.5 too. Added bonus with low pressure is stock internals and motronic can still cope.

Hopefully some progress on this soon, mmmm plasticky.

Ben

Well had a change of plans for the car and a new engine has been aquired.

Lets just say it will be fast


Ben


PS Anyone seen an S54 in an E21?