How can you add more boost with the water/meth if your sn93 is max out with 10lbs of boost. I'm running a 3.75 sc pulley and a 6"crank pulley both 8 rib setup. if I add more boost it will over spin right.
Printable View
How can you add more boost with the water/meth if your sn93 is max out with 10lbs of boost. I'm running a 3.75 sc pulley and a 6"crank pulley both 8 rib setup. if I add more boost it will over spin right.
If you're currently seeing 10psi of boost from your SN93, then you're more than likely over spinning it as it is (these blowers don't typically produce more than 8psi at their intended maximum RPM). For you to gain any additional boost from your SN, then you'll have to over spin it even further beyond it's intended maximum RPM.
Water/meth injection doesn't "add" more boost. What it does is allow you to run more boost by dropping the compressed air temperature and reducing (or eliminating) detonation. But, running that additional boost is only possible if the supercharger your using has room to produce more (through the use of different sized pulleys). As I said, if your SN is pushing 10psi then from the sounds of it you're already spinning it beyond it's intended maximum RPM which means there probably isn't much more room (if any) for additional boost.
I'm only seeing 8-9 lbs of boost. I brought a devilsown kit with the dual nozzel havn't installed yet. I was told to spray 1 jet before the charger and 1 after. The smaller jet before the charger will add a 1-2 lbs of boost by cooling the air charge. is this correct? and is there anybody using water/meth with a sn93. I would like to know how it's working for you and HP gains.
This is the first I've ever heard of spraying meth before and after the charger. All the kits I've seen spray meth after the blower, although I will admit my experience with water/meth injection is limited.
I will buy into the notion that installing a meth injector before the blower will cause the in coming air to be cooler before entering the blower, but all else being equal I don't see how that will result in an increase in boost pressure. Unless - as I said above - you spool the blower to a higher RPM.
But hey why not try a cheap experiment: since it's still the middle of February, before installing the injector kit wait for a really cold, dry day (I'm sure we'll still see a few of those before spring) and take the car out for a quick run. If the notion of cold inlet (to the blower) temperatures results in higher boost, then you should see it reflected on your boost gauge on a cold winter's day. I'm pretty confident in saying meth injection won't drop the inlet temperatures below typical ambient winter air temperature, so if you don't see a gain in boost on a cold winter's day then I seriously doubt you'll see it from injecting meth into the blower.
Michael: All kits I've seen sale a dual jet nozzle. I talked to a few of them. They all say a pre jet will cool the condense air in the charger which results in more boost with the cooler charge. Thats what they all tell me ( AIS,DevilsOwn,CoolingMist). With the SN93 being limited to making boost the pre jet would help me out. Your thoughts and anyone else is appreciated. Do you know anyone else with Sn93 and Water/Meth.
I thought when your car is cold you have more HP as the car heats up you loss HP. That the reason for the water/meth for cooler air charge and cooler temps. Thats the reason for the pre jet to cool the hot air inside the charger. You think?
As I said, I have very little experience with water/meth injection. The SN89 I bought came with a water/meth injection system (from Blowerworks, formerly the Carroll Supercharging Company) and it only has a single nozzle mounted after the blower. But this is an older water/meth system; obviously newer systems have advanced somewhat.Quote:
Originally Posted by Ghost88
Hopefully someone with an SN and water/meth injection will chime in soon though.
How much boost are you running with your sn89 and how is the water/meth working out. I have a 88 foxbody with fmu 30s and 255 pump. I have a question I put the 30s in no fmu haven't driven the car due to weather. At idle the wideband shows around 16.2 is that because the fmu isn't hooked up. I thought the fmu only work during boost.Quote:
Originally Posted by Michael
Unfortunately, the blower isn't installed on the car yet. It's in desperate need of a rebuild before I can use it... something that I am hoping to do very soon. I probably should have mentioned that in my earlier post... sorry.Quote:
Originally Posted by Ghost88
Correct about the FMU working only under boost.
Ghost88 are you running a HO impeller? I have a SN89 w/ Ø3.75 pulley on my '86 Mustang. I am also running an HO impeller but don't have a boost gauge. I suppose I should get one (a gauge) to see where I am but just haven't.
Yes I have the HO,anderson power pipe and bypass valve. I'll be getting it tuned with the meth in April. I'll let you know the numbers.Quote:
Originally Posted by JPJP
Hey Ghost 88, do you have any boost numbers you can share of boost versus engine RPM's? I haven't seen anybody post any numbers like that. Approximate numbers are fine by me.
Boost versus Engine RPM...
I use water injection on my Novi 2000 and have been using it on my VR4.
I use it for protection and in place of anintercooler.
I have second thoughts about spraying on the airfilterside and wonder what would happen to the impeller at 40K rpm when the waterdrubs meet ?
Resurrecting older thread.
I finally but a boost gauge on mine. I am running about 6-7 pounds boost at about 5000 RPM's on my '86 Mustang. This is about where I shift anyway. Bringing the engine to around 5500 RPM's superheats the charge and boost drops to 5 pounds.
I am running a SN-89 with Ø3.75 blower pulley (Ø6 at crank) and a H.O. impeller.
I am right at the edge as far as fuel goes. Very dependent on the ambient temperature. I plan to install a Walbro 255 LPH fuel pump (GSS340) and 24 LB injectors (with matching FMU disk) at this point.
Are you sure it isn't dropping from belt/ball carrier slippage?
Quote:
Originally Posted by JPJP
I'm running 9lbs at 5500 rpm 3rd gear thats with the meth dual nozzle. I haven't had it tune yet. Hopefully I'll pick up another pound with the tune. I'm going next saturday I'll let you all know what happens.
Absolutely no belt dust and no slipping/grabbing characteristics I have had with belt slippage in the past.
Afterthougts:
No evidence of belt slippage.........but the balls slipping maybe. At 5500 RPM's the impeller shaft is just over 39K RPM's. Never thought of that possibly being the case.
Anyway, the '86 yellow lines at 4800 RPM's. I was intentionally over revving to see the maximum boost I could get.
Quote:
Originally Posted by JPJP
If you want to know your boost nail it in third gear to your highest rpm, thats your boost.
I heard either 2nd or 3rd gear for checking boost, but not first since the load isn't high enough. Numbers have been the same thus far.
Quote:
Originally Posted by JPJP
Do you have a by-pass valve? What is your timing set at? Do you have a power pipe. A power pipe will give you 1-2 lb of boost. If you want more boost go with a 7" crank pulley 8 rib setup. The 3.75 s/c pulley is the smallest you can go. If not all that use meth.
Timing is set at 13-14° BTDC base. Still running S.D. with the stock computer.
No by pass valve.
No power pipe.
Ghost88, are you running S.D. or Mass Air?
I converted to mass air. DO you have a boost retard, if not your timing should be set at 10 degrees. Get a by-pass valve for safety that air charge needs some where to go. You maybe want to go with 30s or 42s. When I had 30s my 255 pump wasn't pushing enough fuel so I added a t-rex pump. If you plan on doing any thing else to the motor go with 42s and a t-rex. If no plans 24s and a 255 pump will be fine.
Quote:
Originally Posted by JPJP
JPJP I belive you can use a BOV since your S/D.
Thanks for your help Ghost88. I am not getting spark knock so I will keep the ignition advanced it is worth 20HP according to Kenne Bell to have the initial advance at 14°.
See attached file.
Nice! Someone boosting with speed density :cool:Quote:
Originally Posted by JPJP
If the harness in my car wasn't pinned out for cbaza, it would have been fun to get it dialed in with speed density.
Have you ever considered a Moates quarterhorse and binary editor?
Mike
Moates quarterhorse and binary editor......never heard of them. I will do some research.
I have heard good things about the Megasquirt systems however.
A good place to start is at eectuning.orgQuote:
Originally Posted by JPJP
From what I understand Megasquirt is more like a stand alone you build or buy semi built and go from there.
Quarterhorse you just plug it in to your pcm and a laptop, buy binary editor, and your ready to start tuning on the fly with the engine running :evil: with real time data logging and good support on the eectuning.org forums.
Imho it should be the 1st mod anyone who owns a performance Mustang should buy. Heck after you finish tuning with the quarterhorse you could even burn your file to a j3 chip and sell the quarterhorse. moates.net is closed this week but I've heard Craig Moates is a standup guy who's happens to be a genius also.
Hope this helps,
Mike
I checked it out Mike. It appears the '86 does not have the correct computer. '87 is the first year that will work.
JPJP, I appologize for any misinformation.
Ghost88, how did the tune work out?
No problems whatsoever. I found out about a new system, just not compatible with my computer.