Installing a supercharger. I need some help.
Discussion
Gentlemen I need some help.
I have this enginebay.
Now the car is lovely, the chassis is capable of carrying at least double the standard power (924s 150bhp, same chassis as 944, with minor mods it was produced as the 944 turbo with 250bhp. Smashing chassis). This isn't actually the car I'm tuning but it is an identical (but red non sunroof shell) car.
The big difference between the 924s and the 944 engine is that the 924s engine was fitted with low comp pistons (hence I can use 91ron fuel lol) to reduce power so it didn't conflict with the heavier 160bhp 944. Obviously low comp pistons are ideal for boosted power, but that isn't to say I could just bolt on the 944 turbo manifolds and turbo/ecu as the valves etc. were different on the turbo engine to cope with the extra heat. However a supercharger installation should be ok.
Now one big issue I'm going to have is fitting the supercharger in the hole I have, the supercharger I'm going for is the cooper S charger for obvious reasons, it will be operating at it's limits of capacity, but it's cheap and easy to find, plus I don't want to be running silly boost, I just want a gentle increase in power through the range.
Fitting the charger isn't a concern for me though, I do a lot of fabricating work. But............
I understand the mechanics of fitting it, I can probably squeeze an intercooler in, does it go before or after the supercharger? After would make more sense as it would cool the air that is heated by the supercharger, but would this not cause a lag?
Also is a blow off valve needed?
As you can see I have a MAF meter, in theory this should still work as it works on measuring the amount of air flowing past it, although more air will be flowing it should still function.
One issue I do have is bearing in mind I don't have a lambda probe is there a simple way to measure the afm to make sure it isn't leaning out anywhere?
I have this enginebay.
Now the car is lovely, the chassis is capable of carrying at least double the standard power (924s 150bhp, same chassis as 944, with minor mods it was produced as the 944 turbo with 250bhp. Smashing chassis). This isn't actually the car I'm tuning but it is an identical (but red non sunroof shell) car.
The big difference between the 924s and the 944 engine is that the 924s engine was fitted with low comp pistons (hence I can use 91ron fuel lol) to reduce power so it didn't conflict with the heavier 160bhp 944. Obviously low comp pistons are ideal for boosted power, but that isn't to say I could just bolt on the 944 turbo manifolds and turbo/ecu as the valves etc. were different on the turbo engine to cope with the extra heat. However a supercharger installation should be ok.
Now one big issue I'm going to have is fitting the supercharger in the hole I have, the supercharger I'm going for is the cooper S charger for obvious reasons, it will be operating at it's limits of capacity, but it's cheap and easy to find, plus I don't want to be running silly boost, I just want a gentle increase in power through the range.
Fitting the charger isn't a concern for me though, I do a lot of fabricating work. But............
I understand the mechanics of fitting it, I can probably squeeze an intercooler in, does it go before or after the supercharger? After would make more sense as it would cool the air that is heated by the supercharger, but would this not cause a lag?
Also is a blow off valve needed?
As you can see I have a MAF meter, in theory this should still work as it works on measuring the amount of air flowing past it, although more air will be flowing it should still function.
One issue I do have is bearing in mind I don't have a lambda probe is there a simple way to measure the afm to make sure it isn't leaning out anywhere?
Packaging could be interesting, but I guess that you can always make a bonnet bulge. If you are running near the limits of the cooper S charger, and they are cheap enough, you could always run two in parallel. Intercooler always goes after the supercharger.
The MAF will probably work as long as it doesn't exceed its airflow/voltage limit (possibly 5v). If it does you can probably bodge it a bit with a resistor.
You will need to increase the fuelling as well, maybe a higher pressure fpr will do it.
If you can make any use of Audi B5 S4 intercoolers, I have a couple spare.
Steve
The MAF will probably work as long as it doesn't exceed its airflow/voltage limit (possibly 5v). If it does you can probably bodge it a bit with a resistor.
You will need to increase the fuelling as well, maybe a higher pressure fpr will do it.
If you can make any use of Audi B5 S4 intercoolers, I have a couple spare.
Steve
Cheers Steve, I think packaging will be ok as while the gap is awkward it is deep, so it should fit without a bulge.
Intercooler wise I'm not sure, it very much depends what shape intercooler I can find, I don't want to block the rad, so may have to fit the turbo front panel and mount it off to one side, thats a job for after I have the charger mounted.
Intercooler wise I'm not sure, it very much depends what shape intercooler I can find, I don't want to block the rad, so may have to fit the turbo front panel and mount it off to one side, thats a job for after I have the charger mounted.
wildoliver said:
, the supercharger I'm going for is the cooper S charger for obvious reasons, it will be operating at it's limits of capacity, but it's cheap and easy to find, plus I don't want to be running silly boost, I just want a gentle increase in power through the range.
I understand the mechanics of fitting it, I can probably squeeze an intercooler in, does it go before or after the supercharger?
After would make more sense as it would cool the air that is heated by the supercharger, but would this not cause a lag?
Also is a blow off valve needed?
As you can see I have a MAF meter, in theory this should still work as it works on measuring the amount of air flowing past it, although more air will be flowing it should still function.
One issue I do have is bearing in mind I don't have a lambda probe is there a simple way to measure the afm to make sure it isn't leaning out anywhere?
WOI understand the mechanics of fitting it, I can probably squeeze an intercooler in, does it go before or after the supercharger?
After would make more sense as it would cool the air that is heated by the supercharger, but would this not cause a lag?
Also is a blow off valve needed?
As you can see I have a MAF meter, in theory this should still work as it works on measuring the amount of air flowing past it, although more air will be flowing it should still function.
One issue I do have is bearing in mind I don't have a lambda probe is there a simple way to measure the afm to make sure it isn't leaning out anywhere?
iirc the Cooper blower is the Eaton 45, these have a bypass chamber so you don't need a blow off valve.
6psi should see you somewhere around 200bhp without temps high enough to warrant an intercooler & the problems involved with the increase in volume on the intake tract.
Not sure if your MAF will work correctly downstream of the blower, you may need to reposition.
Hope that helps
FB
ps brings back memories of a previous car mod I did....
If you're only running low boost then you neither want nor need an intercooler. The pressure drop across an intercooler would actually outweigh the benefits of charge cooling at low boost pressures. The efficiency of the Eaton blowers is best at low boost levels so it seems like a reasonable approach as long as the blower you use has adequate flow capacity. From memory the M45s are good to about 14,000 rpm, you would need to define the upper rev limit of the engine to decide what gearing that would cope with and the total effective displacement.
You don't need a blow-off valve but would definitely benefit from a recirc valve to take the load off the blower under cruise conditions. This will reduce wear and keep everything cooler ready for when you want the power. Water injection upstream of the blower helps seal the rotor (increases efficiency) and reduces the charge temperature which gives you added protection even though you probably don't need it.
I assume you'll be replacing or tweaking the fuel and ignition management to cope with the extra air flow and give you boost retard.
ETA: I would certainly put the MAF sensor upstream of the blower, it's unlikely to be read accurately if you make significant changes to the charge density.
You don't need a blow-off valve but would definitely benefit from a recirc valve to take the load off the blower under cruise conditions. This will reduce wear and keep everything cooler ready for when you want the power. Water injection upstream of the blower helps seal the rotor (increases efficiency) and reduces the charge temperature which gives you added protection even though you probably don't need it.
I assume you'll be replacing or tweaking the fuel and ignition management to cope with the extra air flow and give you boost retard.
ETA: I would certainly put the MAF sensor upstream of the blower, it's unlikely to be read accurately if you make significant changes to the charge density.
Edited by GreenV8S on Thursday 14th August 16:34
The plan is to keep the MAF upstream of the charger, good news that I won't need an intercooler, one less packaging job. I'm hoping the standard ecu will handle the supercharger without modification, there's only one way to find out!
Re the valve for cruising to take stress off the charger, if the m45 does have this chamber then is that still necessary?
Re the valve for cruising to take stress off the charger, if the m45 does have this chamber then is that still necessary?
wildoliver said:
Re the valve for cruising to take stress off the charger, if the m45 does have this chamber then is that still necessary?
I haven't seen an M45 with integral recirc valve close up. If yours has the integral recirc valve then that's all you need. Do check that the vac reference used to operate the recirc valve is connected externally so you can connect it to the manifold downstream of the throttle. If it's connected internally then your proposed downstream throttle layout could be problematic since the blower will never see manifold vacuum.wildoliver said:
I understand the mechanics of fitting it, I can probably squeeze an intercooler in, does it go before or after the supercharger? After would make more sense as it would cool the air that is heated by the supercharger, but would this not cause a lag?
Lag due to plumbing will be negligable.Intercooler MUST go between supercharger and engine.
wildoliver said:
Also is a blow off valve needed?
Depends on location of TB. If you intend using a typical intercooler, then I would be placing the TB close to the engine, which means you would definately need some form of compressor bypass/dishcarge.This is due to length of plumbing between TB and engine....ideally you want this volume to be as small as possible.
wildoliver said:
As you can see I have a MAF meter, in theory this should still work as it works on measuring the amount of air flowing past it, although more air will be flowing it should still function.
Throw the MAF away and fit a proper ecu.wildoliver said:
One issue I do have is bearing in mind I don't have a lambda probe is there a simple way to measure the afm to make sure it isn't leaning out anywhere?
There are dozens of widebands available, as per another thread.Ok if I do go down "proper" ecu territory, I need the cheapest way possible, but I don't want to have to make it myself, I understand that megasquirt I have to build from scratch? I don't mind assembling, but I hated building circuit boards in GCSE electronics, does anyone make a kit with a properly built board?
Also what else can I do with it, can I remove the MAF totally and go for (is it called map sensor?)?
What would I need to add to the engine, I assume a tps, knock sensor and lambda probe?
Can I map it myself, I realise I won't compete with a proper engine mapper on a rolling road but I rather fancy trying, bear in mind I do understand A/F relationships as I build and tune engines on carbs at the moment.
Also what else can I do with it, can I remove the MAF totally and go for (is it called map sensor?)?
What would I need to add to the engine, I assume a tps, knock sensor and lambda probe?
Can I map it myself, I realise I won't compete with a proper engine mapper on a rolling road but I rather fancy trying, bear in mind I do understand A/F relationships as I build and tune engines on carbs at the moment.
TBH the M45 isn't big enough by quite a margin for a 2.5, you run out of revs before you get enough boost. My project will run a Vortech V5 from the US was around £500 on fleabay.
Done loads of spreadsheets to get the numbers but it looks like 7-8psi boost to give around 310BHP on an S2 lump, mine'll be in a 944 Lux.
Some pics of some dummy brackets & tryouts are here:- http://www.pbase.com/tr7v8/944_sc_project
I've a M62 blower off Merc C200 in the garage but it's a bulky beast & I couldn't work out a way of getting it in the engine bay. If you're interested PM me.
Done loads of spreadsheets to get the numbers but it looks like 7-8psi boost to give around 310BHP on an S2 lump, mine'll be in a 944 Lux.
Some pics of some dummy brackets & tryouts are here:- http://www.pbase.com/tr7v8/944_sc_project
I've a M62 blower off Merc C200 in the garage but it's a bulky beast & I couldn't work out a way of getting it in the engine bay. If you're interested PM me.
wildoliver said:
Ok if I do go down "proper" ecu territory, I need the cheapest way possible, but I don't want to have to make it myself, I understand that megasquirt I have to build from scratch? I don't mind assembling, but I hated building circuit boards in GCSE electronics, does anyone make a kit with a properly built board?
Also what else can I do with it, can I remove the MAF totally and go for (is it called map sensor?)?
What would I need to add to the engine, I assume a tps, knock sensor and lambda probe?
Can I map it myself, I realise I won't compete with a proper engine mapper on a rolling road but I rather fancy trying, bear in mind I do understand A/F relationships as I build and tune engines on carbs at the moment.
On a budget, VEMS is probably a better route to take, as they offer fully built units that will do what you want.Also what else can I do with it, can I remove the MAF totally and go for (is it called map sensor?)?
What would I need to add to the engine, I assume a tps, knock sensor and lambda probe?
Can I map it myself, I realise I won't compete with a proper engine mapper on a rolling road but I rather fancy trying, bear in mind I do understand A/F relationships as I build and tune engines on carbs at the moment.
basic engine sensors required for efi in boosted form.
Crank rotation/position, ie 36-1 or similar trigger
MAP sensor
TPS
Engine Coolant temp
Intake air temp ( not totally essential )
That would be a bare minimum an ecu needs to run an engine.
Right, found out what a map sensor, that doesn't scare me off, the tempo sensors are fine, in fact most of them may even be there as standard, certainly my 964 had an airflow temp sensor fitted, the car doesn't have atps fitted as standard but it shouldn't be outside my capabilities, I assume it is just a rotary pot that records the position the throttle is in?
I do have a crank sensor, it's mounted on the flywheel, now I know all cars have different systems, just like they have different impedance injectors, for example I know my old 964 had a lot of lumps on the back of the flywheel and just a couple of missing teeth, yet rovers have very few teeth. Does it make any difference or is megasquirt customisable to take advantage of this? What I don't want to be doing is taking the engine out and modifying the flywheel.
I do have a crank sensor, it's mounted on the flywheel, now I know all cars have different systems, just like they have different impedance injectors, for example I know my old 964 had a lot of lumps on the back of the flywheel and just a couple of missing teeth, yet rovers have very few teeth. Does it make any difference or is megasquirt customisable to take advantage of this? What I don't want to be doing is taking the engine out and modifying the flywheel.
wildoliver said:
stuff about fitting an S/C with microsquirt
Have you had a look at pelicanparts.com? There are several appropriate threads there e.g. http://forums.pelicanparts.com/showthread.php?t=36...Good luck!
Good link that, at least the tps question has been answered, use a stock 951 throttle body as it has tps built in.
What I do worry about is how unreliable all their cars seem to be, I really don't want something that is always requiring fiddling, I just want to do it right once and leave it alone unless I upgrade it further.
What I do worry about is how unreliable all their cars seem to be, I really don't want something that is always requiring fiddling, I just want to do it right once and leave it alone unless I upgrade it further.
wildoliver said:
Good link that, at least the tps question has been answered, use a stock 951 throttle body as it has tps built in.
What I do worry about is how unreliable all their cars seem to be, I really don't want something that is always requiring fiddling, I just want to do it right once and leave it alone unless I upgrade it further.
Dont forget....lots of reliability issues are from people tackling jobs, that are way beyond their capabilities, or them tackling them on a budget.What I do worry about is how unreliable all their cars seem to be, I really don't want something that is always requiring fiddling, I just want to do it right once and leave it alone unless I upgrade it further.
I know from an ecu point of view....Id rather just pay the extra for a known reliable, user friendly ecu. Like you....I dont want to start having to build it myself.
I'm quite used to dealing with peoples bodges and mistakes, I organised a tour of europe for a very well known tuning company famous for using superchargers, which degenerated in to a farce as almost without exception the cars broke down in varying forms, all related to bad workmanship and varying from simple not tightening up of battery terminals, right up to a car blowing it's injector rail apart as he had used water hose as opposed to fuel hose........scary stuff.
The mechanical side of things isn't a concern at all, the brackets I'll make up will be agricultural and strong, and if the intake manifold doesn't fall right then I know a good alloy welder so will just modify and fabricate it up, generally any work I do looks factory and is done properly, although i take longer to do the job as it's done right.
Likewise wiring will be secured properly, rubber bungs used where it has to pass between bodywork etc, all the things that people usually forget or don't bother with, and cause the niggling reliability problems.
But it does still deeply concern me as I will be taking a car I can just jump in and drive, and really don't want to turn it in to an unreliable toy, I have other cars for that, but at the same time another 50-100 brake is very tempting. Plus I'd like to get the experience of megasquirt on a £500 car as opposed to doing it for the first time on my next toy project which will be 15k plus.
The mechanical side of things isn't a concern at all, the brackets I'll make up will be agricultural and strong, and if the intake manifold doesn't fall right then I know a good alloy welder so will just modify and fabricate it up, generally any work I do looks factory and is done properly, although i take longer to do the job as it's done right.
Likewise wiring will be secured properly, rubber bungs used where it has to pass between bodywork etc, all the things that people usually forget or don't bother with, and cause the niggling reliability problems.
But it does still deeply concern me as I will be taking a car I can just jump in and drive, and really don't want to turn it in to an unreliable toy, I have other cars for that, but at the same time another 50-100 brake is very tempting. Plus I'd like to get the experience of megasquirt on a £500 car as opposed to doing it for the first time on my next toy project which will be 15k plus.
id say go for a centrifugal blower, like the Rotex, proChargers or Virtech. they can make big power for relativly small size and are easier to package.also as they are liek a turbo they are often easier to plumb when compeard to a roots style blower.
the other advantage is you can probably leave the intake manifold and throttle body as is. you will just need to run a Blow Off Valve (BOV) inbetween the blower and the throttle.
how are you planning on tunning the thing??
Chris.
the other advantage is you can probably leave the intake manifold and throttle body as is. you will just need to run a Blow Off Valve (BOV) inbetween the blower and the throttle.
how are you planning on tunning the thing??
Chris.
Is tunning tuning or turning?
Assume you mean turning I have a serpentine belt driving the alternator and it is very short, the routing is perfect to allow me to run a longer belt and run the supercharger off it too.
I did think of a rotrex or similar, but I don't like the underbonnet heat they produce, and more importantly they are very expensive!!
I'm aiming to have the complete car running sub 1k, a rotrex would blow that budget.
Assume you mean turning I have a serpentine belt driving the alternator and it is very short, the routing is perfect to allow me to run a longer belt and run the supercharger off it too.
I did think of a rotrex or similar, but I don't like the underbonnet heat they produce, and more importantly they are very expensive!!
I'm aiming to have the complete car running sub 1k, a rotrex would blow that budget.
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