Cyborg

iTrader: (8)

I don't really think they are "secrets" because Slowhawk has posted this before but some things that make a big difference in tuning out belt slip are:
- Precise pulley alignment
- Reichard brand pulleys
- 8 rib upgrade (obviously)
- belt brand might make a difference
- and maybe there are some secrets too ...but I don't think so

6techniques

iTrader: (7)

yeah but it would seem streetability would be horrible and/or overkill with a gear driven setup, especially on a streetable blower like the d1-f1a models...or are you referring to the chain drive?

irun4cops

Ok, ive got a 02 z06 with a forged 383. Right now ive got the d1sc, and a front mount intercooler. I have a 3 inch pulley on the d1sc. Im prototyping an idea that hasnt been perfected yet...

I have a valve that bleeds off excess boost. So if 15psi is my limit, i put on a pulley that makes 30 psi at max rpm, and when the boost hits 15 psi at 3000 rpm, all excess boost is blead off. This is also nice for altitude changes, engine never feels more than 15psi, and no need to change pulleys. Reason for doing this is to make more hp sooner and expand my power band all while keeping my engine reliable.

Ive been thinking about going to the f1a. I have heard that for street and roadcourse use... the cogged belt wont work since downshifts will be hard on everything (belt needs to slip). ... if this is not true, then I will consider it again. Im not into drag racing on the track very much.

I have a 12 rib system now. Im about to upgrade to a carbon kevlar belt. Belt slip and belt wear/stretch are my enemy.

I cant make too much boost, it just helps me come up to 15psi at a sooner rpm. I AM worried about HEAT however. I do have an intercooler, and water alcohol injection. Point I want to raise is... since I am limiting back pressure to 15psi, will the f1a make a lot more heat then the d1sc? If I got an f1a, i would probably put on as small as pulley as I could without belt slip... so the 3 inch if it doesnt slip.

Ive never heard an f1a... loud huh?

TS6

iTrader: (41)

About 10,000 other people here have mentioned that same setup and every time we have to explain why its a very bad idea. You are still beating the blower hard, probably over spinning it with a 3" pulley, and creating ALOT of heat, and making it that much harder for the motor to turn that blower. Changing pulleys is not hard at all, and if you want 15 psi why not just pulley it for 15 psi?

irun4cops

At what rpm is a d1sc capable of making 15 lbs of boost?

At what rpm is a f1a capable of making 15 lbs of boost?

If you pulley either of these to make 15 lbs of boost (at lets say.. 3000 rpm), then what happens when you get to 7000 rpm?

If an engine can only hold 15 lbs of boost, and you go over that, what happens?

Without the valve, how do you recomending keeping the system under 15 psi at max rpm, and still making 15 psi asap? If theres another solution, im all ears.

TS6

iTrader: (41)

Not to be critical, but it sounds like you should do some basic research on blowers. Boost is just backpressure, what makes 15 psi on my car might make 18 psi on another.

The answer to your last question is turbo.

irun4cops

turbos are laggy. Laggy is the opposite of boost asap. Anyone with a supercharger knows thats the main advantage to owning it, when you hit the gas, you have boost now, not in a couple seconds from now. Its already spinning, turbos arent. Im just taking it one step further. Id rather have supercharged 15psi now, instead of 8psi now.

Back to my original post tho... any advice if i should stay with a d1sc or upgrade to an f1a?

irun4cops

The first 4 questions are rhetorical... they all boil down to the last question... im a bit sarcastic sometimes.

TS6

iTrader: (41)

Turbo's aren't laggy if they are properly sized.

Like I said, not to be a dick, but it really sounds like you don't understand how this stuff works.

First, the turbos are already spinning, they spin from the second the engine starts. From what I've seen here, many guys have full or near full boost by 3500 rpm or so. Thats pretty quick, and honestly, very uncontrollable on the street. My car makes 730 at the wheels at 6500 rpm. At 3000 (I think) rpm, I'm making about 550. That breaks tires out every time, I couldn't imagine how bad it would be making 700 at 3500.

Second, I don't think anyone buys a blower kit over a turbo because of turbo lag, its because the blower kit is usually cheaper, much easier to install, and readily available. Turbo kits for F bodies have evolved as of late, but alot of guys have headaches with the kits and the people who build them. You can order a blower kit today, have it tomorrow, and install it in a very short period of time. Most turbo setups have taken guys months (or years) to get, and it takes much longer to install one.

I've owned a few turbo cars, and a couple blower cars. When built properly, they feel similar. The only time I've had turbo lag problems was when I had a torque convertor that was too small.

If you're pullied for 15 psi, with a properly setup combo, you should see around 11 or 12 psi the instant you mat it. I don't know how much power you're making, but unless you are at the track on slicks its gonna spin.

You really need to get over the "psi" thing and concentrate on power, as in how much do you need/want? Remember, more airflow=less boost, which is not a bad thing. My buddies BBC with a little blower makes 1-2 psi, but you bet it hauls ***. If he put that blower on a smaller engine, it would make more boost but still less power.

Do some reading here, there is a ton of great info. I'd make a new thread if I were you and ask your questions again.

kp

iTrader: (34)

Not to burst your bubble but its been tried a few times before, by both a wastegate type setups and restricting the inlet.

Neither has shown any significant gains over a normal setup except maybe on the dyno. But if you want to spend the time and effort I am all for people trying different things so go for it.

But to answer your question the F1A will make more boost then a D1SC, if thats what you want then try it. An F1C will make even more, so will an F2 and so on.

stevieturbo

There is nothing new in what you are toying with. Dozens have tried before, and they usually realise it isnt worth it.
As others have said...get this psi thing out of your head. Its BS. How do you know how much boost a X" pulley will make ? You dont, nobody does unless they actually test it on a motor.

If you have a 12 rib system, and slip/stretch/wear/alignment are problems, then you really need to sort those issues out first. Spinning the blower harder/faster than necessary, is never a good thing. Both in terms of belts, pulley drives, and blower bearings, and your so called hate...heat..
The fact that you say you have slip/stretch issues now, leads me to think you have serious problems that need addressed !!! Of course, if you didnt spin the blower as hard, maybe you wouldnt have such problems

After some early belt problems, I run a 12 rib on my Vortech V7 YSi. I now have zero belt problems. Zero belt stretch. And Zero slip. This is with a 63" Gates belt.
Belt path, and support/idlers appear to be very important. Once I got this sorted, I havent looked back.

I just need to find the right tension, that wont be too hard on the blower bearings ( assuming that is what caused them to fail recently )

Ive been using the same belt since early October, some 20+ passes, maybe 4,000+ road miles and a manual tensioner. Belt tension has not changed during that time, and I have not touched the belt drive system in any way during that time ( aside from when I hade to repair the blower a couple of weeks ago ). Dust around the belt area is minimal.
I re-used the old belt, and will continue to use it until it breaks. it is still in excellent condition.


Another aspect about a 12 rib drive for those thinking about it...belt lengths in 12 rib do start to become harder to find. Be sure they are available in your length, before you get pulleys made !!

NemesisC5

irun4cops

yeah, im getting the belt slip issue fixed. I have a spring loaded tensioner... think i should go to a manual tensioner instead? Im aware that psi isnt only what its about, psi and flow are directly proportional variables once a supercharger is hooked up to a given engine. Since some people cant see that psi and flow can be asily interchanged in this conversation, lets talk flow...

If an engine can only hold a certain amount of incoming air temp which is increased by... air and the propper amount of fuel to match... and then it has detonation or worse... blows up, so you stay below that suggested threshold of incoming air temp, which is increased by increased compression (psi) of the air which is caused by FLOW.

Now... youre already spinning the tires are your max hp (600) and max rpm (7000)... so whats next? Well, your car doenst have "spin the tire power" at lower rpms, so there is room for improvement in that rpm range, but anymore power up top is useless bc you are already spinning. So you decide you want more FLOW at lower rpms, but dont go over your threshold up top. So you get a VALVE to release excess FLOW at higher rpms bc you are gearing the supercharger to make more FLOW at the bottom rpms... thus your supercharger makes more FLOW at higher rpms since it is spinning faster, but the increase FLOW is not getting to your engine. FLOW and HEAT are not directly related as PSI and HEAT due to the simple fact that compressing air (psi) causes air to warm up. Bleeding off FLOW isnt going to change temps. Bleeding off PSI does. The valve bleeds off the excess of both bc they are direcly related variables. Increased FLOW is what causes increased PSI when the air is trapped in a fixed volume system.

Your car started at 600 rwhp at 6800 rpms. Obviously it didnt make near that at lower rpms. Instead of wasting money upgrading your engines hp across the board which would result in 800 peak hp just so that you can spin the wheels at lower rpms bc now it might make 550 wrhp at 3500 rpms... instead you put a valve and a smaller pulley on the supercharger... and solve your problem for under 300 bucks.

Or maybe its a horrible idea since its not on anyone elses car, and 10,000 people have already tried it to no prevail except for myself and this guy with a smaller engine than mine...

http://www.corral.net/forums/showthread.php?t=173455

Its too bad the other 10,000 people havent got it working, and that people waste money on engines that can handle over 800hp when the power is useless anyway. But they will argue that they have more useful power at lower rpms. I agree, im just saying theres an easier way.

Whether or not this makes sense to you yet doesnt bother me.

The useful info I have gathered from this thread is that the f1a heats the air much more than even an overspun d1sc making the same psi.

Obviously the 2 superchargers are pullied to different speeds, the d1sc faster. And since its the same engine, with the same intake volume, and the air only has one place to go... we know that the same PSI also means the same FLOW bc if there was more flow and no where extra for that FLOW to go, it would raise the PSI of the entire system... in agreance on simple physics i hope?

Yes, engine size makes a difference, but when you are keeping it all on the same engine, the supercharger flow and psi are mathematically directly proportional numbers, if one raises so does the other.

But just incase im wrong, Ill go "read up" on how this stuff works a bit more.. but probably not here bc i got blasted by several people "trying not to be dicks" who freaked out when i used PSI instead of FLOW, even tho they are proportional bc i made it perfectly clear that this was for a single z06, no other cars involved.

TS6

iTrader: (41)

OK dude, go for it. Don't listen to people who have 100X the experience you do and are trying to help. Its good to have ideas and theories, but its also good to listen to people who know their ****, not that I am one of them, but I have taken the advice from some that do. It should be really easy to understand why this idea doesn't work.

Just for future reference, NEVER link to the corral for proof an idea is good, it accomplishes the exact opposite. Next to the ricer forums its the biggest group of dumbasses you'll meet.

stevieturbo

you're flogging a dead horse.


But keep at it if you like....you have already given yourself problems with this approach, and will encounter more.

For no reason whatsoever.

Eventually you will realise its pointless

TS6

iTrader: (41)

Some people gotta learn the hard way.

Oh well, at least it gives them good experience spinning wrenches and hopefully learning about their car.

Pro Stock John

iTrader: (34)

Renegade Mustang guys run 8.5-8.6's with 8 rib belts...

kp

iTrader: (34)

My dog has fleas.

cablebandit

iTrader: (37)

Your dog has fleas cause you bought a really good converter.
Kp, what is your IAT gain from start to finish in the 1/4 on the low 9 sec passes?

Pro Stock John

iTrader: (34)

Renegade Mustang guys run 8 rib belts into the 8.6's on a regular basis, so if you can run 9.1's like mister smartypants you are not far off from the guys who run them to the limit. Renegade guys run strut braces, and have the belts very tight. Here is a pic of my old YSi setup with strut brace: