HP at the rear wheels

inovermyhead

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Just got my car back from having a new ecu fitted( Haltec Platinum Sport 2000) and the dyno report shows 153hp at the wheels.... Is this what I can expect with a 1989 3.5 and no other performance mods other than s/s headers and full Fritz bits exhaust, stock cam, later big valve head?

John
 
Well that's how the transplant came and after replacing the stock 3.0 and 4 speed, I spent a small fortune on bodywork cutting out the rust and a full back to bare metal respray. From a new headliner to new carpets, now it looks a million bucks but the wallet is drained.

But next year.... I've been reading up on Metric Mechanics site re high comp Pistons , longer rods and yes possibly a cam, not quite convinced on the benefits of the flowed head though as mine already has the late big valve head?
Any advice gladly received .

John
 
I want to stay away from the turbo route, happy to have an honest 250/270hp ( at the flywheel ) and would look at throttle bodies possibly ,Jenvey UK make some TBs that look like old school webers that look great and might make a bit more power.
I'm thinking 95mm pistons with 10.5/11 cr should give a bit more oomph
 
My CS has a 1991 M30B35 with Weber DGEVs. The intake manifolds are ported to match the carbs and the intake ports on the head. Otherwise, the motor is stock, with stock B35 exhaust manifolds and a 2.5" exhaust. Here is my dyno chart from a couple of years ago. About 165hp and 185lbft at the wheels. I've made a couple of minor changes since then, and I expect it makes a few hp more now at a higher rpm. I'd expect your motor to make the same or better. That said... dynos aren't all the same.
30cs-dyno.jpg
 
For now you can think about running it at the dyno with 91 octane
Change your timing after your baseline pull
 
I think a Shrick or Paul Burke (he still around?) would be the biggest HP jump w/o tearing out the pistons.
 
The Paul Burke cam adds 40 HP to a stock B35 but unfortunately, he has all but disappeared and, in some cases, with customer money. A bummer since is product was really good.

If I recall correctly, my B34 3.3L with Schrick 284 cam, dual 38s and stockish exhaust did 165 HP at the wheels last year.
 
The Paul Burke cam adds 40 HP to a stock B35

Tod,
I've been trying to search for some dyno sheets to prove this, but all I can find is a lot of trash talk on many different forums, some of them quite entertaining.
I don't know if it's just me, but I have a hard time believing that a 218hp M30B35 will put out 258hp after just a (n31?) cam (and software?)

Are there dyno sheets to prove this?

Cheers,
 
IMG_2280.JPG
First- the m30 b35 is rated as 208 hp not 218hp
It's the m90 and eurospec b34 that are 218hp.

I ran the m30 b35 with the Burke hot cam on the dyno for a bunch of pulls this year and the results were terrible.
149hp was the best I could get.

Last year I managed 193hp with a eurospec engine and Schrick cam
I have installed a few of Paul's milder cams and felt they were fine.

With Paul gone it's hard to say what went wrong.
W&N sells the Schrick for a good price.
Not on their website but they carry it.
 
First- the m30 b35 is rated as 208 hp not 218hp
It's the m90 and eurospec b34 that are 218hp.

I ran the m30 b35 with the Burke hot cam on the dyno for a bunch of pulls this year and the results were terrible.
149hp was the best I could get.

Last year I managed 193hp with a eurospec engine and Schrick cam
I have installed a few of Paul's milder cams and felt they were fine.

With Paul gone it's hard to say what went wrong.
W&N sells the Schrick for a good price.
Not on their website but they carry it.

Ah, yes I was a bit too fast there, 208hp is correct.
About the 193hp eurospec engine, do you remember which Shrick cam you used and was it otherwise stock?

Lots of questions but I have an e32 735i with the eurospec B35 that I will (in the future) use in my e9, so I'm slowly trying to figure out a nice recipe on how to put it together.

Cheers,
 
IMG_1483.JPG The b34 heads need porting no doubt to get good results.
Not so much for the b35.
In my book it is the cam, porting and compression for results.
Once you have those you run 91 octane and a good fuel/timing map.
250hp is a number you can attain with everything done right.
 
Another option for camshafts is Dbilas of Germany which offers ten different camshaft grinds for the M30. My initial thought during the rebuild process was to use a Schrick but I thought the 284 to be on the "too low" side of aggressive while the 308 probably a bit too lumpy at idle and with diminished drivability under 2000. I might have been perfectly satisfied had I chosen either of them, but in weighing (my perception) the pros and cons, decided to go with the Dbilas 300. A good deal of time went into port & polish as well as matching the manifolds, a process which as earlier mentioned will allow the camshaft to achieve its maximum design results; gotta let the air pass through unrestricted. Mine is a 3.2 and not carbureted, so not a direct comparison to the subject 3.5 but I'm very pleased with the HP output and especially the torque curve which is quite flat from 2700 - 5200.

Best,
Jim

Couldn't find this yesterday...

GRAPH%20FOR%20Bavaria%20JVO%20DJ%20equiv%20on%202016-07-21%20%40%2012-10-11-L.jpg
 
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Not sure what spec my m30b35 is, but it came out of an e34 7 series that would have been Oz delivered and may have been detuned for hot climate conditions and possibly running lower comp Pistons. It showed good even compression when installed, as I remember it was between 165 and 170 across all six cylinders.

I remember being a little disappointed after installing it in comparison with the old 3.0 which seemed to spin up quicker and pull harder in the mid range, but this I put down to the engine management cpu (microtech) not being tuned well.
Now I have a proper cpu installed and dynoed by the manufacturer I expected to make up some of that loss , but still it feels a bit meh...

Plans for next year, unless I hear lots of compelling reasons not to, are, head,cam, rods and Pistons ect from Metric mechanic bought as a kit and assembled here in one go.

There is another option, a mate has an early m88/3 from a M5 but I believe the installation is no walk in the park and that I I rebuild my m30 at least I have a known engine as opposed to something that could go bang !!
 
That looks really good for a 3.2. What compression are you running? I'm wondering how that cam would suit an M30B35 at 9.0:1.

Another option for camshafts is Dbilas of Germany which offers ten different camshaft grinds for the M30. My initial thought during the rebuild process was to use a Schrick but I thought the 284 to be on the "too low" side of aggressive while the 308 probably a bit too lumpy at idle and with diminished drivability under 2000. I might have been perfectly satisfied had I chosen either of them, but in weighing (my perception) the pros and cons, decided to go with the Dbilas 300. A good deal of time went into port & polish as well as matching the manifolds, a process which as earlier mentioned will allow the camshaft to achieve its maximum design results; gotta let the air pass through unrestricted. Mine is a 3.2 and not carbureted, so not a direct comparison to the subject 3.5 but I'm very pleased with the HP output and especially the torque curve which is quite flat from 2700 - 5200.
 
That looks really good for a 3.2. What compression are you running? I'm wondering how that cam would suit an M30B35 at 9.0:1.

The compression ratio is 9.5:1; I likely would have bumped it up to 10:1 but the pistons were ordered before I made the mid-stream decision to use ITBs, wasted spark and ECU over triple Webers and a distributor. The precise control of fuel metering & timing with a programmable ECU opens the door to higher CRs but I'd already crossed that bridge. That said, however, I am extremely pleased with the engine's performance and attributes. It idles fairly smoothly, doesn't balk when the revs are below 2000 and pulls very strongly throughout the range. I don't have any acceleration numbers but seat-of-the-pants feel is very (similar) to that of my departed E28 M5 which was 400+lbs heavier. I would think that the 300 cam would be perfectly suitable for your 3.5 and especially so if augmented with improved port flow.

Cheers,
Jim
 
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