M42 Rotrex (for sale!) + track build

[rix313]

Awsome Geoff

So at with the engine at 2000rpm, the charger will suck in about 150m^3/hr while spinning at 4500rpm, producing 1.5 bar of boost? And so on and so forth?

Yes please Ant


EDIT:

Engine at 2000rpm, the charger will suck in about 150m^3/hr while spinning at 4500rpm, producing 0.45 bar of boost.

[GeoffBob]

Awsome Geoff

So at with the engine at 2000rpm, the charger will suck in about 150m^3/hr while spinning at 4500rpm, producing 1.5 bar of boost? And so on and so forth?

0.45bar boost actually (measured at the compressor outlet) corresponding to a pressure ratio (over the compressor) of 1.45 (assuming 1bar pressure at the inlet) at an engine speed of 2000rpm.

Similary around 0.8bar boost @ an engine speed of 6500rpm. problem is that's almost 12psi unless my calculations are wrong

Appletree, you said you got 8psi boost at 6500rpm with your EatonM45 in an earlier post? I've checked and double checked my calculations but I get keep getting 0.8bar. Any chance this is what you meant?

[hoshy]

Is it possible that valve overlap will account for some pressure drop?

[rix313]

From an article about the Cooper S Works: '...increasing the stock supercharger’s boost from 11.6 psi to 14.0psi'

[GeoffBob]

Is it possible that valve overlap will account for some pressure drop?

'Accounted for in the volumetric efficiency (provided Rix cams are the same as Appletree's).

The calculations are the same as I used for Appletree and I knocked his setup pretty much on the head. All I did for Rich was change some of the input values to the model. Only way I think the above could be wrong is if Eaton's flow map is wrong, otherwise I think this is pretty much how she'll perform.

What sort of boost did you make Hoshy and was your EatonM45 setup the same?

[GeoffBob]

From an article about the Cooper S Works: '...increasing the stock supercharger’s boost from 11.6 psi to 14.0psi'

OOOOh?

Looks like I might not be too far off the mark then

Rich, you may be in for a bit more power than you expected! So long as you can get your inlet air temp low enough that you don't have to phaff around trying to stop detonation! My gut tells me that if we are heading for this kind of boost you would actually want to lower your compression ratio, but until I have done some further calculations I'll let others who have more experience on the M42 speak to this issue.

[Ant]

Ok M42 B 18 pinout for stock JPT88 connection( I cut the plug and header off the stock ECU and soldered to the pins loom was not touched! )

1= Fuel Pump relay control( ground switched ! )
3= Injectors 1 + 3 ( ground switched )
6= ground !
8= Check engine light(not fitted to 'UK )
12= TPS Signal
14= ground !
16= Cam Syc ( cyl indentification)
17= fuel rate output to cluster and OBC
24= coil #3
25= coil #1
26= 12V input (switched )
27= DME relay control ( gnd switched !)
28= ground
29= ICV control ( PWM grounded )
32= Inj 2+4
34= ground
36= Evap purge valve
37= 02 heater relay control
43= common ground( TPS and IAT spliced in as OEM )
44= Cam synch
51= coil #4
52= coil #2
54= 12V input ( perm )
55= ground
59= TPS 5V output
66= crank sensor input
67= crank sensor input
73= road speed signal
74= tacho output
77= IAT input
78= coolant temp for ECU)

Any pins I've missed are not of any interest.

all the grounds need to be looped back to a good chassis ground !!!

I did not use the OEM COP setup as its crap, I swapped in a Berligo coilpack and ran it all wasted spark .

Note the injectors are NOT sequential but batch fired so no real need for the cam synch unless you wish to retain the COP as-is.

All the above is tested and verified, so if you duplicate this and have issues, don't blame me

[hoshy]

Is it possible that valve overlap will account for some pressure drop?

'Accounted for in the volumetric efficiency (provided Rix cams are the same as Appletree's).

The calculations are the same as I used for Appletree and I knocked his setup pretty much on the head. All I did for Rich was change some of the input values to the model. Only way I think the above could be wrong is if Eaton's flow map is wrong, otherwise I think this is pretty much how she'll perform.

What sort of boost did you make Hoshy and was your EatonM45 setup the same?

Mine was not a partiuarly good example. It was making about 5.5 but I think I had a bit of belt slip / boost leakage.

[appletree]

Geoff on daves dyno it made 8psi according to his system

when me and my dad checked it on his digital metre (the same one i used in the rotrex setup) we got a peak and hold of 10psi.

heres my old dyno print out.


Purple lowest line is the boost.

[GeoffBob]

Where did you and Dave measure your pressure, before or after the laminovas?

[appletree]

oohh good thought geoff, sure it was after at daves and think when me an my dad tested it first time it had the same manifold in but no laminovas in the manifold so before ish???

[rix313]

I have a gearbox bolted to my engine

[GeoffBob]

I have a gearbox bolted to my engine

Not long now eh Rich? Hard work, but worth it in the end.

oohh good thought geoff, sure it was after at daves and think when me an my dad tested it first time it had the same manifold in but no laminovas in the manifold so before ish???

Not sure that I trust Daves pressure gauge (but in his defence its not exactly a critical instrument, the accuracy of the dyno is far more important) and I'm certainly not sure if you could have dropped a whole 2psi over your laminovas ??

I have however been through my calculations a number of times and the more I look at them the more I think it is actually possible for the EatonM45 to do 12psi at 6500RPM with the above pulleys (so long as Eaton have been honest with the M45 compressor map).

What may be of interest to you is that 530 cubic metres per hour of air (as on the graph I posted) equates (at standard temperature and pressure) to roughly 0.19 kg per second of air. At an AFR of say 13:1 that equates to a mean effective work output of 175kW or 235hp. But before anyone gets too excited, the work required to drive the roughly 56% efficient EatonM45 at P2/P1=1.82 is 18.9kW (and thats properly calculated). That leaves only 156kW or 209hp at the flywheel. Ring any bells Appletree? Not too far off your 205 (.5) hp me thinks.

What's quite scary is that if only 56% of the 19kW going into the compressor is going into compressing the air through the roots pump, 44% of it is going into heating the air, not to mention that due to adiabatic heating!!! To put it another way, the Eaton45 is roughly an 8kW heater through which your intake air passes. Now you know why your laminovas had such a hard time Appletree. At an 6500rpm the 0.19kg/s of air flowing through the compressor is heated to 118'C, ouch! Rich, your FMIC should do a lot better sorting this out, but honestly, the bigger FMIC you fit the better to avoid heat soak. For short sprints and drags you won't need to worry, but if you plan to punish her round the track you might need to consider a more efficient cooler. Just a thought.

Also, make sure your belt is properly tensioned. 19kW is a lot of power to commutate through a belt and it will slip given the chance, as Hoshy experienced.

[hoshy]

That 209 is also what I saw when I kept things cool with the big dyno fan.

[GeoffBob]

Yip. looks to me as if keeping things cool is the secret to getting this one right!

I'll post up my calculations at some point just in case anyone thinks I'm conveniently posting numbers after others have given pointers. Appletree, I saw your 205hp, but missed your 209hp Hoshy.

After all this talk of turbochargers I have to admit that I'm itching to fit one to my 1800cc pickup that's rusting away in the back garden. As much as I love turbocharged engines, 200hp peak with instant and convenient torque on tap is very appealing in a daily driver.

[rix313]

Do it!

Geoff, I think we can safely trust your calulations but would be great to see them and save a copy it's good to have the experience of previous conversions against full on calculations, brings it all together really.

Yeah was a mission but it's on just need to sort the prop out, get my modified exhaust back, starter motor, go see how many months that takes me

[GeoffBob]

Do it!

Yeh!! I think is definately going to be my next project. Poor old pickup needs a good rebuild anyway and having the engine out will give me an excuse to tidy up / de-rust the engine bay. Both EatonM45's and Toyota SC12's are available locally, as well as Rotrex (although I doubt I'd find a Rotrex secondhand). Given that it's a pickup truck and that it does carry heavy loads I think a roots pump for low down torque will be ideal. I still love my two turbo engines though.

Geoff, I think we can safely trust your calulations but would be great to see them and save a copy it's good to have the experience of previous conversions against full on calculations, brings it all together really.

Oh, I doubt you can trust me as far as you could throw me but I like to type up my work so that others can duplicate what I have done if they would like to. Spreads the love, if you see what I mean. It also means that if there is something wrong in my work then hopefully someone will pick it up and then I get to learn too.

[rix313]

Fitted my starter today, what a shit job how can something so simple be so anoying.

By the time the engine has the loom box, fuel lines, my oil lines, brather pipes and a strut brace, it makes it impossible to get to the back bolt, had to pull it all off to get the nut on there and tighten it

C'est la vie, all back together now but my arms and hands are all stinging from the various cuts I achieved while cack handedly ramming them in any available space.

Bleed the clutch, prop adjustment, exhaust, then I imagine instead of starting it I'll have missed something stupid and spend all day looking for it Joys of owning a turd.

[hoshy]

...spend all day looking for it Joys of owning a turd.

Just a day, you'll be lucky

[smith4130]

some one stole my car out of storage the weekend.......... it gona be a long time before i get somthing together to complete this build......

[rix313]

Roten luck there mate.


Right well turned the key toda, hasn't started made a small video. Aside from that there's a very odd clunking noise which keeps happening I'm wandering if its the AFM flap pinging open and shut.

There was some fuel left in the tank and I've just put 5.5 litres in it.

[youtube][/youtube]

[rix313]

Bollocks to that SHE FECKIN RUNS NOW SON!!

Havening not done a 'first start' I was being abit impatient lol. There is no exhaust on it hence why it sounds like a monster truck. It did run a little smoother the first time but then for the camera it started beig a bit funny. Any way here's the vid:

[youtube][/youtube]


So ended nicely today. Went and got a proper fixing kit for the lecy fan anc fitted that, managed to track down a 17mm alan key socket so I could change the gearbox oil, drained it all out then to save ball ache, ran a piece of pipe out of the gearbox and through the gearstick hole with a funnel Also found the out the heater/blower does work so I don't have to start a fight with that either

Here's some shots of the bay:

[appletree]

M42 rightness

Great work rich! its a good moment when a fresh build starts and running it with no exhaust is just the LAW!!!

I should be down at stonehouse again next tuesday/wednesday if you want to borrow the big torque wrench for the crank bolt

[rix313]

We had ear defenders on because weren't too sure how loud it would be lol.

I wont be needing it just yet mate, I'm poping it on the other engine so Alex can align The super charger with it. Prob about another month or two though if thats cool bud

[appletree]

ya no probs, if your coming to the pod show i could drop it off to you then with the pully tool bit aswell and then pick it up another day when i'am down that way?

[rix313]

If I can get there sounds like a plan, shan't be in the BMW though.

Had a tinker with the throttle and settled the idle down, runs perfic now

[GeoffBob]

Well done Rich, looks and sounds fantastic!

FYI, I have started a write-up on the M42 with EatonM45 here
I'll present all of the relevant calculations there instead of bombarding your thread with them.

[rix313]

Awsome thanks Geoff

I've had a U-turn on the exhaust side of things. Come to the conclusion that 2" system would more than likely restrict me when it comes to fitting the charger and all so going to have a 2.5" system made localy by a friend of mine I'm going to neaten up the power flow one though with a smaller end pipe and sell it on if any one's interested

So I've fitted the shitty one back on for now so the car isn't so defening. It blows like your nan with no teeth but does sound quite good lol (the exhaust )!

As it's back on I ran the car up and left it running occasionaly revving it to get it to temp so I could check for leaks etc. As it warmed, the exhaust wrap started to brown and fill the garage with fumes of what ever kind, this coupled with all the WD40, brake cleaner and oil I've dropped on the engine that was burning off . Also after looking for leaks, I found one obviously there was an airlock in the coolant system so it started getting rather warm and wee-weeing water on the dusty floor . After bleeding it a little the rad started to warm up and I'll give it another run later.

[GeoffBob]

Fantastic stuff Rich, sounds like you're really making good progress You must be feeling really pleased with yourself.

According to Graham Bells' Forced Induction Performance Tuning you'll need a 2.5" pipe to support 180-220hp. Bare in mind however that to deliver your roughly 200hp to your flywheel your engine is probably doing closer to 240hp worth of work due to the effort required to drive your supercharger. This is work that the engine is doing that you will never ever "see" at your flywheel, but your engine is doing it (and the byproducts thereof flowing down your exhaust) nonetheless. Thus to support 210-265hp Graham Bell recommends a 2.75" diameter pipe. Personally, I'd recommend you run 2 x 50mm diameter pipes due to the difficulties in running a 2.75" toilet pipe.

I'm assuming here that you have an exhaust header to match all of this? For a 4-into-1 header you should be looking at four off 1.25" header tubes at 15" to 30" long. You could also consider building up two off two-into-one exhaust systems (1st and 4th cylinders down one pipe and 2nd and 3rd cylinders down the other) with a x-piece joining the two somewhere under the car. If your wallet is in the mood this is the way I would suggest going.

And never underestimate the effect of your exhaust system on your engines performance!

[rix313]

Yeah, for me, had some real good progess the last couple of days It's still over heating like mad so going to take the thermostat out and chuck it in some hot water and see if it's jammed or something. Other than that the engine runs fine, just gotta fit the prop and run through the gears.

With regards the exhaust I'm going to make something that's similar to the BMW one but makes some noise at the same time. I'm actualy going to be using mostly BMW parts to make it. M42 down pipe, part of OE front section to allow for easy marrying, then two performance silencers from local motorsport supplier, to an E36 rear section as it has a nicer smoother bend to the back box.

[smith4130]

fair play..... looks and sound the dogs......

[rix313]

Stupid thing wont start now

The cooling system is (or was when it was running) being a pain in the tits as well.

Joy of owning a turd

[GeoffBob]

Any bubbles showing up coming through the coolant Rich? I assume you fitted a new head gasket?

Also, how does your thermostat perform. Take it out and pop it into a mug of warm water with a cheap thermometer. Then slowly add hot water to see at what temperature she opens (if at all).

[hoshy]

Good work so far Rich. I'm sure you'll get these problems sorted soon enough.

I had loads of crap with mine too - it's just the way it goes sometimes, particularly for guys like us who are/were doing it for the first time.

[rix313]

I put it in a bowl of boiling water and it opened although it is abit stuff. Also after it was up to temp I took the hoses off then poured water in the top water hose and water did come out of the lower hose I haven't changed the HG although is was done a couple of years ago, I did get some bubbles coming up through yes when trying to bleed the system. What I found was the upper hose was getting very hot but the radiator wasn't.

It did start today oddly, I think my fuel pump is being a little funny. IIRC I had issues a couple of years ago when I had it then.


Going back to this:

Also roughly worked out what PSI I'm going to require:

Desired BHP
Current BHP

200
135

= 1.48

Boost = 0.48 x 14.6 (atmospheric pressure)

= 7psi

GeoffBob wrote:
What may be of interest to you is that 530 cubic metres per hour of air (as on the graph I posted) equates (at standard temperature and pressure) to roughly 0.19 kg per second of air. At an AFR of say 13:1 that equates to a mean effective work output of 175kW or 235hp. But before anyone gets too excited, the work required to drive the roughly 56% efficient EatonM45 at P2/P1=1.82 is 18.9kW (and thats properly calculated). That leaves only 156kW or 209hp at the flywheel. Ring any bells Appletree? Not too far off your 205 (.5) hp me thinks.

Now obviously my first caculation for desired engine power did not take into account the huge amount of power required to run the charger which Geoff pointed out so to even further back up on what's already been said:

Desired BHP
Current BHP

235
135

= 1.74

Boost = 0.74 x 14.6 (atmospheric pressure)

= 11.39psi (2dp)