Garett

GDM - E36 Drift/Race Project

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post-2228-1308050661.jpg This is the beast haha 2.5 stroker to 2.8L M20 light flywheel m50 intake and double valve spring ported head m52 exhaust manifold...etc post-2228-1308051201.jpg I need help :blink: does anyone know where to get a larger outer crank pulley (6pk pref) for my m50b28 to speed up my SC14 blower before i install it, maybe somebody might know if there is a larger one on a different car that will fit or can be modded to fit, any help would be much appreciated.... :unsure:

Edited by Garett

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Sorry i'm not much help with the pulley. What size are you wanting? Are you mounting it in place of the ac or up by the intake?

Is it a non vanos head on the block? or what (or where) did you get the valve springs from?

Sounds like a sweet car. I don't think the sc14 is the best idea though. I'd looked into this awhile ago and they would be so far from efficient. There's a merc m62 on trademe that is bigger and would be more suitable. But even that is still on the small side for a 2.8

Edited by bbs

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Brent that pulley looks like it will do the job, where do i go to get one of those??

I was looking around today and i found a 6pk e46 power steering pulley that would be perfect i would just have to make a 42.5mm alloy spacer and drill the holes out.

with regards to the FPR at the moment is 3.5 bar, going to 4 bar not a bad idea??

Because i got one off a Audi and turned the bit that goes in the rail to the size BMW so it'll fit..

Edited by Garett

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Sorry i'm not much help with the pulley. What size are you wanting? Are you mounting it in place of the ac or up by the intake?

Is it a non vanos head on the block? or what (or where) did you get the valve springs from?

Sounds like a sweet car. I don't think the sc14 is the best idea though. I'd looked into this awhile ago and they would be so far from efficient. There's a merc m62 on trademe that is bigger and would be more suitable. But even that is still on the small side for a 2.8

Yeah SC14's are cheap, i have it already and im curious to see if it will give me a few more horsy's.

Im running a m50 non vanos head, block and 2.5 con-rods, m52 2.8 crank and piston heads. running a m20 flywheel the lightest one of the three they run, with the 318is manual behind it.

Pulley around 135-140mm for 8PSI i think i can make a e46 power steering pulley work thats 137mm and 6pk :D , and seen as i have already removed the stupid after market ac compressor the guy before me had put on id put it there... so it goes up on the hoist this weekend for fitment, and hoping i can make it fit there.

Edited by Garett

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Question: :unsure: Is 163hp with 156ft lbs at the rear wheels not bad for this kind of set up, non charged??

Edited by Garett

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Brent that pulley looks like it will do the job, where do i go to get one of those??

I was looking around today and i found a 6pk e46 power steering pulley that would be perfect i would just have to make a 42.5mm alloy spacer and drill the holes out.

with regards to the FPR at the moment is 3.5 bar, going to 4 bar not a bad idea??

Because i got one off a Audi and turned the bit that goes in the rail to the size BMW so it'll fit..

http://www.koperformance.com/BMW/turbo_sup...2_boost_kit.htm

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thats about the hp i had on my m52tu 2.8 non vanos before gavin tuned mine and got 195. with the charger and some tuning you could be expecting at least 220 i would say. good luck mate.

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Hey does a m52 harmonic balancer 1st crank pulley fit on the m50 its a sh*t load lighter...

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thats about the hp i had on my m52tu 2.8 non vanos before gavin tuned mine and got 195. with the charger and some tuning you could be expecting at least 220 i would say. good luck mate.

:lollies: ohh ho ho that would be nice, mostly i just want the go go switch haha. that gavin guy, sounds like he knows what hes doin...

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Im going to do some calculations <_< can you please check and correct where you think needed thanks ;)

FIRST CALCULATION (Engine Litres/min @ 0 Psi )

Multiply engine capacity (in litres) times maximum engine Rpm. E.g. 2.8 litres x 6700 rpm = 18,760 litres/minute. Divide this figure by two as engine only fills every second stroke. (18,760/2 = 9,380 litres/min.

This is the engines air requirements in litres/minute at 0 Psi boost.

SECOND CALCULATION (boost ratio)

Add the boost pressure desired (8 Psi) for the engine to 14.7 Psi (atmospheric pressure).

(8 psi boost desired +14.7 =22.7 psi)

Divide this answer by 14.7 and this gives the boost pressure ratio. (22.7/14.7=1.54) This is the boost pressure ratio above atmospheric pressure.

THIRD CALCULATION (Actual air requirements @ desired boost)

Multiply the boost ratio by the litres/minute obtained for 0 Psi and you get the actual air requirements in Litres/min for the engine at that boost. In our example this is 9,380 litres/min X 1.54 = 14,445.2 litres/min for 8Psi boost.

To decide on the correct size of supercharger you need to know :-

1. The swept volume per revolution of the supercharger. (Eaton M62 1 litre/rev, SC14 from a 1G-GZE 1.42 litres/rev, SC12- 1.2 L/rev)

2. The maximum continuous safe operating speed for the supercharger. (Eaton M62 14000 rpm continuous, Toyota SC14 12000 rpm??)

3. The maximum pressure that can be safely produced by the supercharger continuously. (Eaton M62 12 psi, SC14 10-12Psi??? teflon on rotors melts??)

CALCULATION (Supercharger rotor speed)

Divide the desired air flow (14,445.2 L/min) by the swept volume of the supercharger (SC14 from the 1A-GZE is 1.42 litres per revolution). This will tell you the maximum speed the supercharger rotors must be run at to produce the volume required.

14445.2/1.42 litres = 10,172 rpm for the SC14.

So, to make your wanted 8psi happen, you need to spin the SC14 up to 10,172rpm while the Engine is doing 6,700rpm.

10,172 is under 12,000 so you should be safe running that boost.

Its up to you how much boost you wanna run, but remember, the more boost you run, the more heat is created and the harder the charger has to work. SO, the harder you boost it, the shorter the chargers life will be due to heat and wear.

I stole this off another site and changed it to suit me

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eeekkkk thats a brain full if you make the crank pulley 30% bigger than the charger and you should get around 6-8 psi. if my memory serves me well thats what i done and it worked a treat

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I have found some good calculators and sites on my quest:

For Flow conversion, Fuel Injector Size Calculator, Fuel Pressure Modification Flow Calculator

http://www.witchhunter.com/injectorcalc1.php4

For Pulley and RPM Calculator

http://www.culvermotor.com/Engineering-For...Calculator.html

Horsepower Calculator

http://www.superchargersonline.com/hp_calc...or.asp?submit=1

Guide to used superchargers

Japanese imports...Subaru, Toyota, Nissan and Mitsubishi blowers

Dimensions and specs

http://autospeed.co.nz/cms/title_Superchar...94/article.html

How it all works Super Chargers and Turbos

http://www.lextreme.com/turbo.html

If anyone has any more i haven't covered this would be great help if you can list... Cheers ;)

Edited by Garett

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Does anyone know if rb25det injectors will fit??? or whats the good option....

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eeekkkk thats a brain full if you make the crank pulley 30% bigger than the charger and you should get around 6-8 psi. if my memory serves me well thats what i done and it worked a treat

Haha hmmm.... ^_^ .

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For your first calculation you should multiply by the volumetric efficiency at the given rpm as well.

Will add more when i'm more alive

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For your first calculation you should multiply by the volumetric efficiency at the given rpm as well.

Will add more when i'm more alive

Haha Yes Please Do...

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Does anyone know if rb25det injectors will fit??? or whats the good option....

Na man 25det injectors are side feed

Can use rb20det injectors

they around 100cc more than m50 same impedance aswell.

the bodies a bit long but you can still get the fuel rail to fit over them

Also you need to fiddle with the plug to get it to fit.

otherwise m52b28 ones are 50cc bigger and a direct replacement.

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Na man 25det injectors are side feed

Can use rb20det injectors

they around 100cc more than m50 same impedance aswell.

the bodies a bit long but you can still get the fuel rail to fit over them

Also you need to fiddle with the plug to get it to fit.

otherwise m52b28 ones are 50cc bigger and a direct replacement.

Really!! im going to get some and put them in tomorrow then with a 4 bar FPR... ill let ya know how it works out.

This is another handy link

http://bmwfans.info/parts/catalog/

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Do you have a compressor map for the sc14? i can't seem to find one.

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hey mate, i was once apon a time looking to do this aswell. Would love to see how it pans out. I have an injector controller unit and injector block if your interested.

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Really!! im going to get some and put them in tomorrow then with a 4 bar FPR... ill let ya know how it works out.

This is another handy link

http://bmwfans.info/parts/catalog/

Have you got some sort of fuel controller?

with a larger injector youll be running the same cc increase from idle to redline

and 100cc seems a bit much for stock stuff to deal with without fuel control

When I put 20det ones in mine it overfuelled like crazy on idle

to the point where I couldnt rev past 1500rpm.

Id go with m52 injectors and rising rate FPR to start with

and jaycar sell a cheap fuel controller ohterwise apexi safc will work

Are you going to have it on a on/off switch or full time boosties?

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you'll need to factor in the superchargers efficiency into that equation as well.

But as everyone is starting to say your going to need to sort out a way to tune it.

I forgot to ask what ecu it is currently running on?

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dont forget superchargers take 33% of crank power to rotate and the sc14 isnt that big should run max 12psi based on the specs i have here due to bearing failer and intake temps, there ok on little engines up to 2ltr.

get a screw blower like sprintex or whipple

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hey mate, i was once apon a time looking to do this aswell. Would love to see how it pans out. I have an injector controller unit and injector block if your interested.

Thanks man ill keep that in mind..

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