Need to start somewhere.....

I wasn't sure where to post this as it is relative to superchargers, EFI and related items. I am a total newb to the thought of supercharging. I definetely understand the concept behind it but need help getting started should I decide to supercharge. I also apologize if there is a better place on the forum for this post.

The motor I am thinking of supercharging is a sbc 400 with fully forged internals and Dart pro 1 aluminum heads. I know I would need to change slugs to lower comp ratio. As you may have seen in my introduction post, I am on a budget so I'm looking for the most affordable way to do this. I'd like to make 600 or so HP.

1. What model of blowers (not roots) should I be scouring ebay for? Im seeing used and rebuilt units for anywhere between $800 and $1500.

2. Can a GM tpi unit with a bigger throttle body and injectors support the kind of power I'm looking for?

3 Is there a good aftermarket controller and harness to make this conversion easy? Fast EFI looks pretty user friendly but I don't know if they make an electronics kit that is boost friendly.

Thank you all in advance for any insight.

welcome
what compression does the engine have now?
are you dead set on EFI instead of a carb?
does your camaro have this TPI set-up currently?
lastly do any of the used units your seeing have mounting brackets, pulleys, intakes, etc???

Thanks for the reply!

Motor is currently 10:1 and carbureted. I know of a local guy with tons of efi take-off parts. You name it, he's got it. not to mention he's willing to sell me high flow runners, a ported plenum and all other necessary conversion parts for around $400. Seemed like a good thought to me.

I really like the efficiency and tunability of efi; especially when adding boost into the equation. That is why I am exploring that avenue.

I have talked to a couple of sellers that have full or close to full kits. Every time I see a reasonably priced blower I go on a googling frenzy to learn as much about the unit as I can. Haven't found what I think is the right choice yet but have only been on the prowl for a week.

Thanks again for the reply. cheers!

I've ready through your original post, and while I certainly don't want to tread on vinces427bb's toes at all, I'd like to throw in my two cents for consideration and general discussion purposes. However, vince has posed some good questions.

But to try and answer your questions in order:

1. I'm going to assume, given that the engine you're looking to supercharge has a 10:1 compression ratio AND that you're on a budget, that you're probably not interested in going with a set of lower compression pistons. If that's the case, then you'll be limited as to how much boost you'll be able to safely run before you start to experience detonation. I know you've already ruled out roots-type blowers, but given that they don't run a very high level of boost when compared to centrifugal blowers, you might want to reconsider possibly looking for fixed displacement type of blower.

However, if you're dead-set against the roots-type blower then you'll probably have to stick with one of the 'smaller' centrifugal blowers from either Vortech, ProCharger, or Paxton. Their boost pressures won't be so high as to cause too much detonation. And if you're looking on the used market, you should be able to find a good used blower for around $1200-$1500, depending on whether or not there are accessories/brackets/etc... included. I don't know of any kits that were made for the 400cid, so you may be forced to make your own brackets.

2. The original TPI was sized and designed to work best on a 305cid. Even on a 350cid, regardless of porting, polishing, large-tube runners, and big-bore throttle body, the TPI will be very hard pressed to achieve the 600hp mark you're looking for. There's just too much volume and runner length to let the engine breath (and spin) enough to get you the numbers you want. Even if you add boost to the equation, the most you might get from a TPI setup would be about 400bhp... maybe 450bhp. And that's REALLY pushing it. And given that you're running a 400cid, which has a greater breathing capability than a 350cid the TPI would prove to be your biggest restriction.

If you're looking to go with EFI, two intakes worth considering for your application is either the TPiS MiniRam or the Holley Stealthram. Both have a similar design and have the potential to get you to your intended horsepower levels... and then some. The only caveat to either is a) the MiniRam isn't cheap, even used. And finding one for your specific application won't be easy, which may require that you buy it new. If you're good with machine tools you might be able to modify a stock LT1/4 intake manifold to fit your engine, which should cost you less than a MiniRam. And b) the Stealthram is considerably taller than the MiniRam which might prove to be an issue with respect to hood clearance. I'm also not sure if Holley makes a Stealthram that'll fit a 400, so you may need to look into that a bit further. Another option would be to find a tunnel-ram intake manifold that'll fit a 400 and machine-off the carb mounting bowls and weld a TPI plenum over the openings (like a home-made Stealthram). Callaway did this on their Corvette Sledgehammer from the early 90s - google pictures of the car's engine bay to see what I mean. That might help keep costs within budget.

3. A friend of mine uses and programs FAST systems. He races a ProCharged '67 ProStreet Camaro that produces something like 1500bhp. He says the FAST system is the only way to go and deals with boost very very well.

Actually I am willing to put some dished slugs into my motor. I got all the parts for it very very affordably so it wouldn't kill me to spring for some pistons. Just from reading posts here and elsewhere on the web I have gathered that CR in the mid to high 8s would be ideal. Correct?

Given that I am prepared to lower the CR I would like to plan on a higher boost centrifugal.

The thought of modifying an old tunnel ram is really cool! I'm a pretty good fabricator and have access to a machine shop at my work. I'm going to chew on this one.....

that option seems like it would enable me to "salvage" harnesses, sensors, fuel rail, etc. from a donor TPI set up in order to save some $$$.

Great questions and input Michael and Vince! Thanks : )

The compression ratio is heavily dependant on how much boost you're planning to run. But mid-to-high 8's is a good range though. Definitely more boost-friendly than the 10:1 pistons you've got in the engine now.

Modifying a tunnel ram is definitely doable - others have done it so obviously it can be done. The question is whether you can find a used one at a good price.

Reusing sensors won't save you much money. If you can reuse the TPI fuel rails, then you'll save yourself something there... but they won't be easy to mount onto a modified tunnel ram without considerable fab work/modification. Not impossible though.

I think you're biggest hurdle is going to be your budget. While I'm sure you can get lots of parts cheap, there are some parts where you shouldn't scrimp. At the 600bhp mark you're looking to achieve, forged internals are going to be a must (which you've mentioned in your original post). That's going to eat up a lot of your budget.

There are cheap supercharging options, relatively speaking. A good Paxton SN series charger can be had for $600-$900; a freshly rebuilt unit can be had for $1200. These are inexpensive to maintain and operate as they can easily be rebuilt by a competent owner (heck, if you look for one that needs a rebuild, you can get them for $300-$400). However, they are older tech (developed in the early 50s, I believe) so they are limited with respect to how much power they can effectively produce. And unlike newer blowers, they don't deal well with being over-spun, so you can't go in with the attitude of, "I'll just put a smaller pulley and it'll make more boost". Doesn't work quite like that. You can squeeze some more power out of an SN by converting it to what's called a VR-4 (basically installing a different impeller and scroll cover with a larger diameter intake volute in place of the stock SN parts), but VR-4 "kits" or parts aren't easy to find as they've been out of production for some time now. There's rumours that a new batch of VR-4 kits are going to be produced, but there's nothing yet.

You could consider a newer centrifugal blower. They'll offer you the kinds of boost and flow rate numbers you'll need in order to make the horsepower numbers you want, with room for "more". But it'll cost you. The older Paxton Novi2000 blowers produce impressive boost and flow numbers, and are said to be indestructible. There are discussion threads on the forum here that talk about the Novi2000 serial numbers that correspond to those units built by Paxton versus those built by Vortech. A true Paxton unit is what you'd want, ideally. Unfortunately, owners of these units know how robust they are, and you rarely see one for sale, and when you do it's going for a premium.

I should also mention, maintenance parts for newer blowers aren't always easy to come by either. More often than not, manufacturers don't sell or release parts to the public, so you're forced to send the unit back to the manufacturer for any "serious" maintenance the blower may require. Not a big deal, but it's an added cost that (I think) needs to be factored in.

Of course, your other options are to either a) increase your budget, or b) lower your horsepower target... LOL!!

I continue to do more searching, reading, product research etc. after each or your thought provoking replies!

Okay so I continue to lean toward FAST XFI. I have learned that their system doesn't use MAF but MAP instead. Now the air intake plumbing design is even easier right? Theoretically, couldn't I just use a single plane intake with an elbow and universal throttle body? Weld the injector bungs in and bam! done! Okay okay I know nothing is that easy but is the logic sound? The tunnel ram mod idea still has my attention though because it just looks mean. And a local guy has one for $100!

I'd agree with you on the sensors Michael. Fast sells a complete kit to compliment their ECU for less than $150.

My motor already has all forged stuff so I consider that a sunk cost and not necessarily part of the budgeted cost for the efi/boost endeavor. Well, except new forged pistons. $$Cha-ching$$. haha.

My most recent research has me pointed at 60lbs/hr injectors. I know fuel pressure plays a part in this but haven't gotten smart enough on that yet. Any hints?

You need to find out what some of the local people are running as far as EFI is concerned. There will be times you need help considering this is your first rodeo. It seems as if the BS3 seems to be the more popular choice with the XFI close behind.

Two ways you can go, either a throttle body or a 4150 style efi carb plate. So yes, you could just do a tube from the charger to a single plane intake. Edelbrock makes carb style EFI ready single planes with injector provisions already machined in as well with matching fuel rails.

You can find Aeromotive A1000s used and cheap but be careful. Personally I would rather buy electrical items new just to know what I have. You will also need a Boost Refernced Fuel regulator. Again Aeromotive has a few to choose from. This is where things will get pricey in piecing together all of the fuel system. Do not skimp on this part!

http://www.airfuelinnovations.com/do...fold_Chevy.pdf

this is an awsome looking intake set-up,
sounds like what your going for.
looks like a few $$$ but it may give you ideas on what else to use or fab your own.. :)

yeah man. That thing looks cool as H$LL! I'll bet it is pretty pricey.

I'm not sure what intake config I'll do now. I already have a Vic Jr. knock off with the injector bung area cast in. Just need to drill it. Then add an elbow and something like a big mouth throttle body. I'm thinking that should flow 600+HP worth of air and be the cheapest route.