First run on the PROCHARGED 18C

[ky-donzi]

Ok need some help.... 73 mph gps... not much improvement over non supercharged engine

1) Prop $ucks!! I have a bravo 1 with the 1.65 drive. It had a 25 P mirage + stock and preformed very good, I went with a 29 P mirage + and It is horrible!! It cavivtates so bad I thought I had spun the hub. At one time today 3500rpm and about 15 mph....no joke. Anyway it cavitates at low end and seems to have alot of prop slip at top end. My top speed was only up 4-5 mph...GPS 73 today... SO PROP SUGGESTIONS PLEASE


2) First I tested by WOT under boost conditions then killing the key at WOT and reading the plugs... did this 4 times and all results looked the same...very clean electrode with alittle soot around the permiter of the plug threads. I was only able to get 3 psi of boost...at 4500 rpm. LOOK AT THESE NUMBERS AND SEE IF THEY LOOK OK

idle 25 psi FP 20 in/hg
2500 rpm 30 psi FP 5 in/hg
3500 rpm 40 psi FP 0 in/hg
4500 rpm 45 psi FP 3 psi boost

[Air 22]

Ok need some help.... 73 mph gps... not much improvement over non supercharged engine

1) Prop $ucks!! I have a bravo 1 with the 1.65 drive. It had a 25 P mirage + stock and preformed very good, I went with a 29 P mirage + and It is horrible!! It cavivtates so bad I thought I had spun the hub. At one time today 3500rpm and about 15 mph....no joke. Anyway it cavitates at low end and seems to have alot of prop slip at top end. My top speed was only up 4-5 mph...GPS 73 today... SO PROP SUGGESTIONS PLEASE


2) First I tested by WOT under boost conditions then killing the key at WOT and reading the plugs... did this 4 times and all results looked the same...very clean electrode with alittle soot around the permiter of the plug threads. I was only able to get 3 psi of boost...at 4500 rpm. LOOK AT THESE NUMBERS AND SEE IF THEY LOOK OK

idle 25 psi FP 20 in/hg
2500 rpm 30 psi FP 5 in/hg
3500 rpm 40 psi FP 0 in/hg
4500 rpm 45 psi FP 3 psi boost


:smash: The 4 bladed props may hook up better..all you can do is test, test, test props to get results...TRY
26 Bravo One
26 Turbo Fusion
Many others will chime in...good luck and keep us posted on what works for YOU!:wink::cool:

[Lenny]

adding at least a hundred HP at WOT I would think would generate better numbers. ??? 73 is about 4 better than a new-ish one with a 1:50

The 1:65 makes me wonder a bit...

Smart people will help, relax... Are you sure you are running 3 pound pulleys?

Why aren't you seeing 5000-5200 rpms?

With that drive (really being a 1:65) and 4500 rpm's and a 25" prop I see you going 64.5 mph with NO slip. Something is a miss I think. :confused:

[BUIZILLA]

idle 25 psi FP 20 in/hg
2500 rpm 30 psi FP 5 in/hg
3500 rpm 40 psi FP 0 in/hg
4500 rpm 45 psi FP 3 psi boost something doesn't make sense here FP wise...

also, the 1.65 setup may have to go, to get it propped right.. you might want to consider a 1.32 drive..

just my uneducated opinion's

[ky-donzi]

Lenny

I went 68 gps before supercharging the engine. The prop never cavitated and was super responsive. With the new prop it was like the "clutch was slipping" at all rpms.... thats what it felt like anyway. I'm pretty sure that it is the 5lb pulley, but if my rpms are lower the boost would be lower... right???

Buizilla

The FP would come up before I made boost, it would show the most increase at around 5 in/hg. Then when I starting making boost the increase was less substainal. Wonder if the wrong diaphram is in the FMU

[Mr X]

General rule of thumb, each pound of boost is good for
about 25 HP.
Seems like you have 2 issues going on here.
Boost should come on at about 3250 rpms and go to about 5-7
pounds at full throttle. Check for a leak on the pressure side of the pro charger and do the math on your pully to see what you got.
Only reliable way to get it jetted correctly (if it is a carb engine) is with an air/fuel sensor placed as close to one of the exhaust ports as possible.

The 1.65 and a 29 should be fine and handle OK. (you will need about 500-550 HP to run that combo on an 18)
Spinning the 29 with a 1.65 will handle much better than
going with a 1.36 and a smaller prop.

My guess is that you WERE spinning the hub on it.
Mark it with a sharpie on the nut and the prop and see if it has changed after you run it again.

[The Hedgehog]

Ok need some help.... 73 mph gps... not much improvement over non supercharged engine

1) Prop $ucks!! I have a bravo 1 with the 1.65 drive. It had a 25 P mirage + stock and preformed very good, I went with a 29 P mirage + and It is horrible!! It cavivtates so bad I thought I had spun the hub. At one time today 3500rpm and about 15 mph....no joke. Anyway it cavitates at low end and seems to have alot of prop slip at top end. My top speed was only up 4-5 mph...GPS 73 today... SO PROP SUGGESTIONS PLEASE


2) First I tested by WOT under boost conditions then killing the key at WOT and reading the plugs... did this 4 times and all results looked the same...very clean electrode with alittle soot around the permiter of the plug threads. I was only able to get 3 psi of boost...at 4500 rpm. LOOK AT THESE NUMBERS AND SEE IF THEY LOOK OK

idle 25 psi FP 20 in/hg
2500 rpm 30 psi FP 5 in/hg
3500 rpm 40 psi FP 0 in/hg
4500 rpm 45 psi FP 3 psi boost

Don't be frustrated yet. This is not an abnormal first run for those that have never setup a Procharger.

For one, you are not spinning it fast enough to get full boost. I am not sure about the 29 Mirage but I know that the 27 Mirage P is a totally different prop than the 25. A lot of boats hate them but some love them. My 27ZX with lower power loved the M 23 but slipped horribly with a 25. I would try something totally different like one of turbo's offerings. While it does not make sense intutively, you may want to try a Bravo for grins. I have a labbed 26 Bravo you can try if you like.

I would verify the pulley size as well.

Is the throttle response still crisp at 4,000 -4,500 rpm?

The fuel pressure seems way different than big block. So does the level at which boost comes on (some of that may be driven by the prop, which does not make sense to me if it is slipping). Is the blower a M-1?

My M-3 on the big block did not start building boost until 3,800-4,000 rpm

[BUIZILLA]

Buizilla, The FP would come up before I made boost, it would show the most increase at around 5 in/hg. Then when I starting making boost the increase was less substainal. Wonder if the wrong diaphram is in the FMU my opinion is your running out of fuel pump, headed for meltdown if your not careful, get an extra fuel pump on there NOW that can manage the fuel load adequately.

[Mr X]

my opinion is your running out of fuel pump, headed for meltdown if your not careful, get an extra fuel pump on there NOW that can manage the fuel load adequately.

BINGO! excellent point!

[The Hedgehog]

These guys may be on to something. First of all, the typical fuel boost reference pressure regulator used by ATI does not send a signal to increase fuel pressure until you go into boost.

You are right about the diaphram issue also. It could be a problem. I bought a 5 lb system but the regulator had a 7 lb diaphram. It was loading up pretty bad on top after 3 lbs of boost. So bad I could not make it to 5.

I may have all of the diaprams around if you want me to look.

[ky-donzi]

ok guys will check it out soon

Got to look at the intercooler where it bolts to the T.B. the o-ring could be leaking, it was when I first put it togather. I'm going to check the diaphram also.

Could I pull the high preassure hose off the fuel pump and hot wire to pump to see how much pressure it will build?

[Mr X]

ok guys will check it out soon

Got to look at the intercooler where it bolts to the T.B. the o-ring could be leaking, it was when I first put it togather. I'm going to check the diaphram also.

Could I pull the high preassure hose off the fuel pump and hot wire to pump to see how much pressure it will build?

No, you have to have a fuel pressure gauge on it at wide open throttle under boost and load.

Did this come as a kit with new MEFI 3 brain box? If not you will definately melt the engine down in a matter of minutes, if you have not allready damaged it. You can send your old one out and get it re-programmed if you did not get a new one with the procharger.

[ky-donzi]

yes it was a kit, but no it did not come with a new mefi box, it relies totally on the FMU. I only did a short burst and plug checks didn't cruise under boost at all. I relize how important it is not to be lean.

The plugs looked like procharger described, clean electrode and ground strap, with soot on the tread perimiter.

BTW forgot to add that I was getting the sooty transom too.

[The Hedgehog]

yes it was a kit, but no it did not come with a new mefi box, it relies totally on the FMU. I only did a short burst and plug checks didn't cruise under boost at all. I relize how important it is not to be lean.

The plugs looked like procharger described, clean electrode and ground strap, with soot on the tread perimiter.

BTW forgot to add that I was getting the sooty transom too.

I bet you are in cold start mode. Are you running a thermostat and what temps are you seeing.

[BigGrizzly]

You have more than one issue. First the ventilation MUST be stopped or a good reading can not be gotten. Its like tryi ng to get a plug reading by revving up in neutral. Fuel pressure or volume could be low. The soot is an off idle thing and fuel in the exhaust unless your running rich, not likely, or running too cold. The darker chocolate brown can only be gotten after time. a short burst won't do it. The real reading is done not only at the electrode but down in the porcelain. We can talk.

[ky-donzi]

Procharger said to remove the t-stat so I did, and I replaced it with a 120 F one from ATI. I'm not sure about cold start mode. It does idle down after about 2-3 minutes running. I would say that temp gage was at 130-140 tops.

Are the FMU disc marked? When I bought the kit it had a FMU tuning kit with it. I will have to dig it out. One other question. I did tighten the regulator adj screw yesterday and the outcome was more F.P. but it showed mostly at static, not much difference during boost. Does the adj screw adj the F.P. accross the board or just under boost?

[BigGrizzly]

FP is accross the board not just at idle.

[The Hedgehog]

You have more than one issue. First the ventilation MUST be stopped or a good reading can not be gotten. Its like tryi ng to get a plug reading by revving up in neutral. Fuel pressure or volume could be low. The soot is an off idle thing and fuel in the exhaust unless your running rich, not likely, or running too cold. The darker chocolate brown can only be gotten after time. a short burst won't do it. The real reading is done not only at the electrode but down in the porcelain. We can talk.

Griz has an excellent point.

When I was going through this, I was told to get the engine figured out then the prop. This works if you are close on the prop. If you are not the engine won't be properly loaded and you will dial it in wrong. Then it will all change again when you get the right prop!:hangum:

It takes a few times to get it dialed in.

[The Hedgehog]

Procharger said to remove the t-stat so I did, and I replaced it with a 120 F one from ATI. I'm not sure about cold start mode. It does idle down after about 2-3 minutes running. I would say that temp gage was at 130-140 tops.

Are the FMU disc marked? When I bought the kit it had a FMU tuning kit with it. I will have to dig it out. One other question. I did tighten the regulator adj screw yesterday and the outcome was more F.P. but it showed mostly at static, not much difference during boost. Does the adj screw adj the F.P. accross the board or just under boost?

No, the disc are not marked. I think that the bigger disks give you more reference but need to verify that. Too little and bad things will happen. Somebody needs to verify that or be very careful.

And yes, the screw on the regulator should give you an increase in pressure across the board.

One of the problems with those regulators is that they tend to wander around a bit. Usually lagging to the rich side.

I am not sure how high the engine runs in cold start mode.

[blackhawk]

No, the disc are not marked. One of the problems with those regulators is that they tend to wander around a bit. Usually lagging to the rich side.

I don't know a ton about supercharging but I do remember a few threads on OSO about the regulators in the Procharger kit being inconsistant. Many people were replacing them. I can't remember the brand but I know Tyler Crockett was selling them. Just an FYI.

[ky-donzi]

Well i'm going to try something this afternoon I believe. With engine idling I will disconnect the reference line and add a small amount of psi (5psi) to the vac/boost line and see what happens. If I can see for sure that the fuel pump is capible of additional pressure then I just have to worry about psi when higher volume is present. Is this a good place to start?

[The Hedgehog]

I don't know a ton about supercharging but I do remember a few threads on OSO about the regulators in the Procharger kit being inconsistant. Many people were replacing them. I can't remember the brand but I know Tyler Crockett was selling them. Just an FYI.

Tex has one and knows where to get them.

I would try the ATI regulator first. I got mine to work pretty well and never had a sooty transom once I got it figured out.

[BUIZILLA]

with the engine at idle, and vacuum hose disconnected, what pressure do you have? a plain and simple start.... if you adjusted it, and the base came up a little, but didn't change the boosted reading then the base setting was never set right in the first place...

I need a vacation...

[ky-donzi]

Buizilla

Probably correct. I'll ck that and post later. The base was at low 30's and I raised it alittle, but this was with the ref line connected

[BUIZILLA]

put the base at 43, line off.... should be 37ish line on...

get back to me after that

[mrfixxall]

Do you have a mechanicle and a electric pressure fuel pump?

if theirs a mechanical fuel pump before the electric fuel pump that may where the spiratic reading is coming from..

[Lenny]

I need a vacation...
See you and the Critter in Cumberland :D :D :D in two weeks.
Happy Birthday to me, Happy Birthday to me, Happy Birthday to meeee-eeee,... HAPPY BIRTHDAY to me...
Getting a bit old I think... May 18th :)

[ky-donzi]

Ok everybody, more input please

Line on is FP is at 42ish, line off probably little over 50. This makes the engine horribly rich at idle.

I disconnected the reference line with the engine idling and hooked up the air compressor to it at about 8-10 psi of air and FP gage jumped to high 60's,,,,,so FMU is working I would expect to see alit more when I added that much compressed air. I might not be getting enough volume from my fuel pump when there is a demand tho. going to experment alittle more.

[BUIZILLA]

put the base at 43, line off.... should be 37ish line on...
.....

[mrfixxall]

Ok everybody, more input please

Line on is FP is at 42ish, line off probably little over 50. This makes the engine horribly rich at idle.

I disconnected the reference line with the engine idling and hooked up the air compressor to it at about 8-10 psi of air and FP gage jumped to high 60's,,,,,so FMU is working I would expect to see alit more when I added that much compressed air. I might not be getting enough volume from my fuel pump when there is a demand tho. going to experment alittle more.

you may want to add a feeder pump at the tank,on a 18 its a long way to suck all that fuel to the existing electric pump..
electric pumps are designed to push fuel not suck:)

this one here works the best ive found,,little pricy buy will last longer then most electric pumps.

http://eddiemarine.com/store/cart.php?m=product_detail&p=12474&c=43

[ky-donzi]

Buizilla
I forgot to add in that paragraph that I set at your approx setting and idle is much better, what I wanted opinion on was added the compressed air, does that seem to jive?

Mr fixall I have thought of doin this, like a booster pump