wheres my horsepower????

[Ruger]

Hi folks. Any suggestions more than welcome
i put the car on the dyno today to make sure everything was ok and it spun up a dismal 112.6hp
mods are as follows:

bosch 715's 4 pintle injectors
k&n filter + added cai to stock airbox (similar to fogging).
magnaflow cat converter, stainless back box and a resonator. 2 1/4" pipework
AC Schnitzer (apparently) chip
98ron fuel (premium here is 95ron)
fan delete mod
Bosch ignition coils with msd wires
heated throttle body delete

now i recently replaced the o2 sensor which was shot but i suspect the intake pipe and vacuum mess under the manifold to be leaking? will this affect the power?

apart from that the injectors are too small and its a fair bit lean, the dyno operator/tuner said i should step up to 22lb injectors which i agreed with.
He reved it to about 7000rpm but after 6000rpm on all runs power tapers off fairly quickly

After the run i adjusted the cam timing to about 4 degrees advance on the intake cam which gave me some more 4000-5000rpm power but after 6000 it still feels like its revving for no reason.

help :confused::confused:

[haledj]

If you assume stock power than that would be a 18.4% drivetrain loss.

Given the engine is probably pretty old, it sounds about right.

How were your AFR's.

[tjts1]

These guys only put down 104hp
http://www.mwerks.com/artman/publish/features/article_977.shtml
114hp with exhaust and intake.
http://www.mwerks.com/artman/publish/features/article_1182.shtml
So I say ur doing pretty well. I curious to see what how mine is doing with efan, PS delete and 710 injectors.

apart from that the injectors are too small and its a fair bit lean, the dyno operator/tuner said i should step up to 22lb injectors which i agreed with.

Thats been my suspicion all along. Good info. Now I just need to get my hands on those Saab injectors.

[D. Clay]

I found this on another forum. It's only part of the list. I was curious as to what the specs or Bosch part# are for the stock M42. A more complete list is at:
http://www.thirdgen.org/techboard/tpi/98576-injector-flow-rates-per.html
Bosch Injectors
280 150 100, 17.7lb @ 45psi
280 150 114, 18.1lb
280 150 116, 18.1lb
280 150 151, 23.5lb         BMW 633
280 150 152, 22.5lb         Alfa turbo
280 150 157, 21.0lb @ 40psi Jaguar 4.2
280 150 201, 23.1lb @ 45psi 82-87 BMW / 84-86 GM 2.0 OHC / 83-84 944
280 150 203, 18.1lb @ 45psi 85-86 BMW
280 150 208, 13.0lb @ 45psi BMW 323 / Renault Alliance Encore
280 150 209, 17.0lb @ 45psi 83-86 Volvo B200-B230 240 / 740
280 150 211, 14.3lb @ 45psi
280 150 704, 16.7lb @ 45psi
280 150 706, 21.0lb @ 36psi 85-86 Porschw 928 / 85, 88 Saab 900
280 150 710, 23.1lb @ 36psi 87-91 Tempo 2.3
280 150 712, 21.0lb @ 36psi 85-88 Saab 900 / 86-89 Saab 9000 2.3 turbo
280 150 716, 13.1lb @ 45psi 88 BMW 325e/528e / 90 Ford Trucks
280 150 762, 21.0lb @ 45psi 88-95 Volvo B230F 89-91 Peugeot 405 Mi16
280 150 939, 19.0lb @ 36psi 4.6 Ford, 302 HO
280 150 943, 19.0lb @ 36psi 4.6 Ford, 302 HO

What would a good upgrade be with and without a chip?

[Ruger]

thats the graph there as you can see it is a bit too lean

ok so the dyno figures all seem to vary. Its a shame i didnt get a before run but well see how much more power we can get out of it. on this dyno with headwork and cams is it a bit optimistic to aim for 140hp?

The problem in my eyes is peak power is too early. i have another 1000rpm to play with after peak power. just have to find a way to make power up that high.

Edit: thinking about it today folks i think its fairly reasonable. I know this is an honest dyno dealing with it in the past and it seems to be an honest figure for a car that had 136hp at the fly 17 years and 257,000 km's ago I was expecting a little more reading the grassroots article where they made a supposed 130ish rwhp with similar mods. Driving it today as well it doesnt feel all that much slower than a friends e36 328i vert

[robweenerpi]

Mine did about 125hp stock.  I have no power steering or a/c robbing power either.  115 or so would seem about right if those are still on the engine.  I got about 130 with a Mark D chip.  Seems like that is a fairly good tune for a stock engine, it made more power and torque pretty much everywhere.  I haven't had a chance to go back and play with the cams yet.  Mine simply wouldn't make power beyond 6500 rpm with stock timing.

If you want more top end you'll need to retard the intake cam.  Advance will give you more low end but the power will taper off more quickly.

ok so the dyno figures all seem to vary. Its a shame i didnt get a before run but well see how much more power we can get out of it. on this dyno with headwork and cams is it a bit optimistic to aim for 140hp?

I think I could do 135-140 with a balanced motor with all new blueprinted parts.  145-150 with a mild reground cam.

[Ruger]

That sounds awesome.

Regarding cam timing though. How do i know which way to turn the crank since there are no markings. At current i lined up the 2 markers flush with the timing chain case, loosened the bolts and turned the crank anti clockwise looking from the front of the engine. My aim was to advance it. Im 99% sure i did as there is a bit more mid range punch (ive never had traction problems at 80kmh in the wet with the 17" wheels until now) but it felt lacking past 5500?

[robweenerpi]

Advance means you make the valve opening event occur earlier in the engines rotation.  This also puts the valve closer to the piston at TDC because the valve is opening while the piston is still near the top.  Retarding means you delay the valve opening slightly.  This gives you an increase in the effective lobe separation which can helps to make a tad of top end power.  I wouldn't crank the cam all the way retarded because the valve can open to late which creates some pumping losses inside the engine.  They don't have much lift or duration and I doubt it'd do much.

If viewed from above with the wrench on the cam then retarding means you pull the wrench to the passenger side.  Advance means you pull it to the drivers side.  Put a 22mm ratchet on the crank and pull the spark plugs and turn the motor over by hand in its normal direction, make sure there is no interference.  If you put in full advance the valves will contact the pistons.  At least on my motor it did.  I started with standard timing via the BMW blocks, you can use a stiff straightedge too, and then retarded the cam a few degrees.

[Ruger]

Awesome thank you!
One thing though - I take it you are in the USA and your car is LHD?

[robweenerpi]

Radford Virginia.