I need some help! I have a carb'd 355 in my 87 IROC. I will answer any other questions about it but I'm not sure what all needs to be known. I want to go with a Supercharger and from what I've been reading, it looks like Procharger seems to be pretty impressive and certainly has the most informative site and from the turbomustang board - it has been most recommended to get the D1SC. I am curious if i am going to need an intercooler since it looked like from what I read on the Procharger site- that it isn't really a 'must' to use intercooler(s) yet some say to definitely use one. Unless I read wrong, it seemed that it wasn't a necessity if you are doing a blow-thru. Just for more info....I have 3.73 gears in a primarily stock rear, 700R4 rebuilt. I have Dart Iron Eagle milled/ported heads, 10:1 compression, Comp X 274 cam, Quick Fuel 750 carb and the engine built for race & street. I do want to be able to drive the car on the street and enjoy it more than I will be racing it. My goal is to be very competitive on the track but still streetable with minimal tuning because finding people around my area that are willing to teach me anything is NOT easy. Right now my car was dyno'd at right under 300. Since then I've gotten a PTC 10" 3200 converter.

Are there any supercharger users on here and if so, i'd love some tips on what all i need in order to get everything together for an install and also some numbers of what you are running with this sort of setup.

THANKS!!

 

An intercooler is always a good idea. Your compression ratio is a little high for running boost. You'll also need a blow-thru carb and a way to control timing.

 

Is it going to be too high.....will it be a problem?? I realize a few things will need to be done to my carb and have someone that can do those things when the system is installed. :-)

 

An intercooler cools the air after the supercharger compressess it. Compressed are is always hotter.
In order to supercharge your motor without a intercooler, using pump gas you'll want to drop the compression ratio to 8.5:1 or less.
(7.5:1 best) allows the most boost with the least spark retard on pump gas.

If you install a intercooler you can run more compression ratio. 10:1 will allow around 5psi (intercooled) 9:1 will allow around 9psi (intercooled)

Another way around it is "Water/Methanol injection". Google it.

Which dart heads do you have? (180 200 215cc) what is the combustion chamber volume?

 

you can run boost on your engine now, but you would DEFFINATELY want to intercool it with that high of a CR, and i dont think you'd be able to run much more than 6-7 lbs of boost on pump gas. Theres always methanol injection as well. From my research Vortech and Procharger are deffinately the best companies to go with, i would personally go with procharger though. The D1SC would be a good unit and is deffinately able to put 15lbs of boost later on down the road if you rebuilt the engine to handle it so you wouldnt have to do any upgradeing other than pulllies to get more power.

 

I don't want to get into doing anything with methanol.... I am going to have to get everything set up an tuned so that I can just get in and go. I don't know anything about tuning and even though you think it would make it easier to get help being a girl, it actually makes the guys want to help less. :-(

 

At 10:1 compression your kind of pushing it, I hear about these LT1 guys all the time blowing there motors at 8PSI with 10:1 but some last, not sure how they tune thiers so that could be why but if you have forged pistons you have a better chance at getting away with it. If you can get new dish pistons and drop the compression to say 9:1 you don't really need to intercool with lower boost, hell there are like a million blown mustangs out there that do it.

As for tunning a carb with a supercharger I don't know **** about it lol. From what I hear it's not a great way of doing things. If you do want to switch over to FI I would suggest using a holley steath ram and maybe looking at going with one of those Megasquirt engine managment systems, it's more of a DIY type project but it will really help you learn FI and there cheap and kind of cool.

 

If you want to have a 10:1 compression motor blown without that will not self destruct, you have 4 choices.

1. Drop the compression ratio of the motor. (purpose built motor)
2. install a intercooler.
3. Install and use a Water/methanol injection system.
4. Switch over to 110-114 Octane racing fuel or Methanol fuel.

There are some very good books available thru Amazon, many speed shops, your local libary that will explain supercharging and how to set up your motor for the street.

If you primarily just interested in adding extra power for drag racing at the track I'd recomend a entry level Nitrous Oxide System. 150-175 hp. It will add as much performance as a $4000 supercharger. The amount of technical knowledge you need to absorb to use/maintain a N20 system is managable. Cost is a lot less. ($700-900 for a N2O system kit+ a auxilary fuel system+ ignition retard system.) $50-$70 to refill a nitrous bottle.
At this power level you can reduce your drag strip times by 1.5 seconds.
It does not affect drivability. At 150-175hp you can expect little or now reduction in engine life.
This is something you could research, buy all the components and install and maintain yourself.
Best bang for the buck, not hard to understand or maintain. Runs on 92-94 octane pump gas without internal engine modification.

You will need some very high traction rear tires to use all that power.
Drag radial. BFG or MickeyThompson.
DOT treaded drag tire ET street, Quicktime pro,
You will have a lot of fun!!!!!
No guy help nessessary.

 

F-BIRD'88 advice is about as good as you are going to get. Since you want mainly a quick street car that doesn't go to the track that often then nitrous is the best route to take. You will have supercharger power when you want it at the track for 1/4 of the cost. There won't be many bottle fill-ups so it will be cheaper in the long run.

Check out David Vizard's book on nitrous. It has lots of good info. So does his Camshaft & Valvetrain book. It takes some deep reading though. I think I have read the cam & valve book about 10 times now. I learn new stuff everytime I read it that I missed before.

If you try the nitrous and decide you want that kind of power all of the time you may change your mind about the intercooler and water/alky spray. You could also recover most of the nitrous kit cost selling locally or in the classifieds/Ebay.

That is cool that you want to learn this stuff. I try to get my sister's to fix stuff that I work on but they always laugh and say just fix it.

 

I think it depends on how you plan to tune the setup, how much boost you want to run, and what octane fuel you have at the local pump. I'll be the first to admit I'm not experienced with boost on Carb's but I'm sure the Carb itself will require modification/tuning to work with boost and provide the proper ammount of fuel. My car is EFI but the current fuel setup (mechanical FMU) is somewhat old school in the sense that everything is done by pre-defined ratios. Probably similar to how your setup will be. So it adds so much more fuel per so much boost. But along with fuel management, you'll also need to look into detonation control. This would be especially important with the higher compression ratio. On my car (Vortech Charged) I'm using the MSD 6BTM in addition with the Vortech FMU. The 6BTM controls detonation by pulling timing when needed and the FMU controls the fuel by adding fuel when it senses boost. For you I would say do some searches on guys running Roots Superchargers, most of those are on Carb'd cars and then you can see how they did the fuel/detonation setup.