Oks, Ive finally got myself the new front mount, 50mm rad, stainless flange to get my own stainless manifold made up to, apexi ecu, uprated fuel pump, and just got my recon m112 supercharger other day. Sooooooo has anyone got any links on anyone who has already gone down this route. Would be very grateful on any info............ :WaveBye
Ps. The car is a 93 jap fd.
Hi there, any reason you have gone for a supercharger rather than a turbo?
From what I understand the exhaust pulse from a rotary is strong, hence why turbo charging works very well
Supercharging- do you not need good torque for that?
I\'ve heard of it done before, but with middle of the road results
According to the map, that compressor "can" flow up to 1400 m3 of air, which at STD temperature and pressure would be over 60 lb/min. This can translate to over 450 HP@crank. Problem is, that pressure ration is only up to 2.0 which isn´t even 1 bar of boost and operating this very compressor at this flow and PR means efficiency under 50%. Very high discharge temperatures and almost 90 HP to drive compressor alone in these conditions. So what looked like 450 HP is now 360 HP with fuel usage and internal load of former but power of later. Then you will have many problems trying to quiet it down what costs even more money and power.
I really hope that you´re doing it just to be different, since superchargers doesn´t offer any performance, reliability or economical benefit over turbocharging. I´m sure someone will bring the point about throttle response and low-down torque, but both these points were proved as false when comparing apples to apples ie same platform and same power production.
If I understand correctly, right now you have stock twins? As they have more performance potential than what you´re planning to do...
@m1tch. Thought it would be easier on the engine, (no sudden load boosts), and considerably less heat in the engine bay, and then there\'s the noise. A rotary beat, with the whine of a supercharger, must be something nice to hear under load!
@miki. Thats good info lad. Think I understand the basics of what you\'re saying, but i thought running a big m112 with light loadings would be alot better than spinning a smaller m90 alot faster, just to get the same boost, but with way higher air temps, but Im sort of feeling my way in the dark with these plans, so any more info you would recommend would be gratefully accepted! :)
Quote from: playtime;804092Thought it would be easier on the engine, (no sudden load boosts), and considerably less heat in the engine bay
Turbocharger places much less load on the engine, as covered in my previous post, for same measured output power, supercharged engine is internally under much bigger strain and load. Underhood temps are just matter of heat shielding and proper airflow. Huge piece of metal fighting its own inneficiencies won´t help;)
Quote from: playtime;804093Think I understand the basics of what you\'re saying, but i thought running a big m112 with light loadings would be alot better than spinning a smaller m90 alot faster, just to get the same boost, but with way higher air temps, but Im sort of feeling my way in the dark with these plans, so any more info you would recommend would be gratefully accepted! :)
You are right about running bigger unit at higher efficiency than smaller unit at low eff. Power consumption of any pumping device depends on airflow itself, pressure ratio and efficiency at this flow and PR. Bigger unit will just have slightly higher friction losses, but we can ignore it as main thing what needs power is pumping itself.
Forget about boost. Its all about airflow. What sucks about superchargers (not even taking into account their poor thermal efficiency) is their coupling to engine rpms. We could fiddle with sizing, gearing etc. but in the end of the day, it still won´t do what turbocharging can. For example, all these Eaton superchargers have pressure ratio capability not exceeding 2.0 PR, its less than 15 PSI "boost". Speed rating is under 15k rpms. You could spin the engine all the way to the redline with low boost -to not exceed speed rating of SC but now you limit yourself to very low boost in the low-end and vica-versa.
Honestly, if you want forced induction, go turbo. Superchargers plain sucks in everything, even 70 years ago, they powered positive displacement superchargers by exhaust driven turbine, so go figure:chat Turbocharger is just so much better.
Give yourself some solid goals, mainly about power level, choose right parts and enjoy it:burnout
This is very true ^^^^^
I dont think youve taken into account the termal efficiency of the charger! Is it a roots, screw or compression charger? The Roots chargers struggle with inlet temps, so a charge cooler is a must!
Depending on the type of charger will depend on the ratios you need to look at for the rev range. When I supercharged the Atom my charger topped out at 14krpm and the engine redline was 8.5krpm, so was almost 1:2
I was looking at a tripple rotary recently that was running a supercharger. It was running a huge pulley with a clutched charger that released at 4.5krpm. Then the 2 GT3540 turbos took over. It was complicated, but certainly worked well!
I dont think it will be a simple case of bolt on and hope it works...it took me months of research to design the one for the atom, but with over 330bhp out of a k-series it was worth the wait!!
Thanks lads. Very useful info again. For the record, this supercharger is twin screw, and I assumed the new front mount would have cooled intake temps enough, but as I said, I am stabbing in the dark with going supercharged. Part of my plans were to get rid of the rats nest, air pump, ast, and twin turbos, to basically clean up the engine bay, and keep the car as linear as possible in its power delivery thro the rev band, which was concerning me if I went for a large single turbo. Im trying to aim for approx 360-380hp, and wanted her pretty lag free as I plan to get back to the occasional trackday. I do have a t4 flanged stainless manifold sitting in the garage, but wasn\'t sure what turbo to go for to be honest..........
Quote from: playtime;804439Im trying to aim for approx 360-380hp, and wanted her pretty lag free as I plan to get back to the occasional trackday. I do have a t4 flanged stainless manifold sitting in the garage, but wasn\'t sure what turbo to go for to be honest..........
Garrett T04E 57 or 60 Trim with P-Trim turbine in 1.0 A/R T4 housing. Its old school but it works very well for this power level. Or simply Garret GT3582R - potential for 500 HP. Or newly released GTX3576R. Really, there are so many options, its just about personal preference and budget for turbo itself.
Don´t jump on hype about lag and peaky powerband, people complaining about it are using oversized turbochargers and low boost, it happens so often in rotary world its not even funny:2Confused
thanks Miki. :god
Keep us posted about your progress. Mainly, don\'t get caught by internet opinions. Turbo sizing is really simple when you determine what you want. Unfortunately majority of people in rotary community goes to big for street car. For example, if you aren´t willing to go over 1 bar of boost, you will be hard pressed to justify "any" single turbo over stock twins.
There is guy in the US who run non-sequential stock twins (not BNR upgrade) at 1.5 bar of boost. Peak power on the dyno wasn´t as high as large single turbo would produce at same boost, but his terminal speeds over 1/4 mile were on pair or even better than terminals of singles at same boost. Then he converted to 67mm single (T04R) and at same boost, he trapped slower despite higher top end power. It took over 1.6 bar of boost to run better terminal speed. At this point, peak power was 100rwhp higher.
My point is, large single will produce higher peak power, even at same boost as stock twins, but all around, boosted up stock twins will be much faster - till certain boost level - if you aren´t planning for close ratio sequential box:rollin And since you want simplicity of single, go with what I suggested or feel free to ask for other alternatives - there are many:cool
lol, since you are offering, any other non- garrett suggestions? 60000 mile garrett reliability is not the end all, if I could get a cheaper option thats not too laggy....... Thinking Holsett or one of those amercian brands.
Well, I´m not familiar with Holset turbochargers, but with regards to price, you can´t go much better than this http://www.himni-racing.com/index.php?main_page=product_info&cPath=25_29&products_id=1125 (http://www.himni-racing.com/index.php?main_page=product_info&cPath=25_29&products_id=1125)
or this http://www.atpturbo.com/mm5/merchant.mvc?Screen=PROD&Store_Code=tp&Product_Code=GRT-TBO-057&Category_Code=TBN (http://www.atpturbo.com/mm5/merchant.mvc?Screen=PROD&Store_Code=tp&Product_Code=GRT-TBO-057&Category_Code=TBN)
You "could" go with BorgWarner S256 but it would require some work. Turbine inlet flange is advertised as T4 and bolt pattern matches it, but volute entry itself is T3. For optimal work, porting of turbine housing inlet would be needed. Also, turbine housing outlet doesn´t have V-band flange, it must be bought and welded on. By default this turbo is sold with 1.22 A/R hotside - excessively big for this application, for smaller housing, you must pay extra money:( This is very capable turbo, but probably not worth a hassle in this case.
http://www.himni-racing.com/index.php?main_page=product_info&cPath=25_288&products_id=1925 (http://www.himni-racing.com/index.php?main_page=product_info&cPath=25_288&products_id=1925)
Go with full T04E (links on top). If your manifold is divided, choose 1.0 A/R divided housing. If undivided, go with 0.96 A/R undivided. In both cases choose 57 Trim compressor wheel.
Playtime i have a power master t-70 single turbo for sale if your interested. Twin scroll a/r 70 with a hotside a/r.1.0 no shaft play in very good condition. It kicked out just over 500 steroid abused stalions @1.3 bar so im sure it`ll be big enough for your power goals. £300
Check the for sale section.
Cheers Miki. More good advice :)
@turbo boy. I\'ll have a look and see if I can google some info on it. Cheers.
Hi Miki. Im seeing loads of americian supplied t4 divided flanged turbos with AR\'s in around 0.74 and 0.8. I see you were recommending 1.0 AR. Is the lower AR going to be an issue, if I want to run 1 bar, and looking for approx 360 hp? Cheers.
Well, there are very few people who can really say that they found power limit of given wheel and housing combination. Depends on the turbine wheel itself. If its P-trim, then even A/R of 0.6x won´t have problems to make power which you are after. Share your findings:Talking1 Or did you settled on what I suggested?
I had a look at the 2 garretts, you suggested, but I was hoping to find something cheaper, for the sake of loosing some turbo lifespan, as the car won\'t be covering anymore than 1000 miles a year, so I could live with a turbo with a 20k lifespan, rather than the garrett\'s 60k lifespan. I hear people saying not to buy one of those non-branded obviously chinese built turbos, but noone can tell me why not, other than vague "it will blow up the world..............." warnings..........
Chinese turbo can work, but it can be hit and miss. Don´t forget that you are after response - correctly matched turbocharger is must and unless you know for one hundred percent what you are getting, its not worth it. Maybe try looking in for sale section.
Heres a question lad. Just been offered a brand new IHI RH b6 6t-602 turbo. You know much about them? I cant even get any specs when I googled for it. Cheers again :)