I have saving money for a while now and i have about 4k. I had been planning to do the LE2 for the longest time, but then i started looking into supercharging and a rear mount turbo, and I'm leaning more towards the forced induction now. I've been reading alot of posts about it.

From what i gather 6-7psi is safe, and 8psi can be done safely. I was looking around and it looks like i can make 370-400rwhp with just a bolt on supercharger, or rear mount turbo. This is about as good as i could do with with a heads and cam setup, but seems to require much less work, and alot safer as far as installation. See i plan on keeping the stock stall and 2.73 gears because i wont be able to afford to replace them if i do the LE2 and full bolt ons.

I want to be able to run low 12s or high 11s. I want to know how long my engine would last, and how fast i could possibly go. My car is 1995 Firebird Formula, automatic, 2.73 gears, 70k miles, mods in my sig.

How much power would i gain at each boost level of 4.5psi, 6psi, 7psi, and 8psi. Also what other mods would i need? 36lb injectors and a tune right? I would also be adding long tube headers and a 3" x pipe setup (unless i went the turbo route)

I havent really looked into forced induction on the LT1 until now. My last car was a twin turbo 3000gt, and i really like forced induction. What do you all think i should do?

 

heads/cam/spray, thats what im doin. i really want FI but refuse to put it on a motor not built for it, thats just my opinion

 

I dont spray... to me that's not really a win. i dunno, i really like the raw power all of the time. If my motor blows, i rebuild it with my heads, cam, and the supercharger i already have.

With installing the heads and cam, there is alot of work, and alot of risks, not to mention a 1,000 parts and gaskets i need to collect and millions of tiny pieces i need to not lose. To me the turbo or supercharger kit is much easier.

 

ya i hear ya, its a tough choice ill have a forged 355 with a blower one day just no time soon lol

 

If the choice were up to me, I'd say do the heads and cam. There is a little more initial time and effort involved, but there are going to be less problems down the line. Naturally asperated is a more stable platform.

Not to mention that if you want to reach 400rwhp I don't think you're going to get there on just a supercharger. 400 crank sure, but not RW on a stock engine. The STS kit might get you there, but people have been blowing engines with them.

I think you're better off getting a set of AFR's, a nice cam, and a good set of headers.


Oh, and what's an LE2?

 

STS is forced induction just like any other FI. If not tuned and set up properly, it can and will damage your engine. With the proper tune, the STS is a great choice for a bolt on kit.

 

Lloyd elliot stage 2. he ports your stock LT1 heads, puts in new valves springs, bigger valves, and gets them flowing about 270 on the intake side, then he custom grinds a cam for you. His LE2 cam is a mix between the CC306 and the GM 847. He says with full bolt ons you will dyno somewhere around 400-420rwhp.

I wanted to do the supercharging because it will be less work, and no risk of spinning a bearing because of miss installing it, degreeing the cam wrong, adjsuting the rockers wrong, or any of the 1,000 other things. I figure if i break my engine supercharging it, i can rebuild it for FI, run higher boost, and put in my cam, heads, and new parts i was going to.

Also, can i run ram-air and a supercharer? I wasnt sure how the intake was set up.

 

I've done both and I would recommend the heads and cam. With the blower, you won't make a whole lot of power reliably and if you get up over the 400-425rwhp mark, the motor will not last long. In addition to that, you have additional fuel needs requiring upgrades there. You also have heat soak, summer temps, and detonation. You'll have to deal with the increased hassles of working on an LT1 with a blower in an already cramped engine compartment.

I got tired of those headaches and just went N/A. If you do end up damaging the motor and spin a bearing or some other malfunction, you can rebuild it for very cheap and also do a very cheap cast 383 for a reasonable price and be back on the road.

 

Id go heads and cam...only a matter of time til the boost catches up to your stock engine

 

I think you'll get more midrange power with a heads and cam than you will with a supercharger. Compare the dyno curves.

And as for they 1000 pieces thing. Spend $10 on some ziplock bags with labels on them and a sharpe, you'll be just fine.

 

That's exactly what I did - but I spend $1.99 for the cheap store ziplock bags and sharpie from around the house I do that for EVERYTHING now. Also intake manifold bolt order is important - I removed them and put a piece of masking tape around the bolt with the number it was. That way I knew where it went with the drawing in the service manual.

Do you want to rebuild in 3000 to 30,000 miles? Boost "can" be "safe" but with the lt1 it's hit or miss.

I'd say get the heads and cam, buy/build the boost block, then slap the heads on it. Used lt1 blocks with or without stock crank/rods are worth nothing these days and can be had for uber-cheap.

 

i had 4K to spend... i went FI...

then in bit (2 weeks lol) i had to spend almost 5K for the new motor...

 

Why do the intake bolts need to be numbered? I'm pretty good at remembering where stuff goes, but im still gonna separate it all, i dunno about numbering the bolts though.

 

$4k is a pretty good chunk of change. But it can be spent quick and leave you with a debt towards a new engine, especially with boost on a stock bottom end. I guess it depends on how far you plan to take the car in the future as to how the money will be best spent.

If you plan to make 600rwhp+ one day, i'd go ahead and invest it in a strong bottom end with good bearings, forged components, and 4-bolt caps. Then save up for ported heads, cam, valvetrain parts, and some kind of FI. Or even go ahead and start building up your drivetrain first with a good rear end, build that A4 of yours up (you'll need it if you plan to keep it), and good suspension components. I tend to follow the ideal of building up the drivetrain first, then dig into the engine. But you have to have set goals of what you want before even starting on a build-up to do this.

 

Everyone wants power now so rebuilding is not usually in the topic until it happens. Not that it shouldnt be done
Anyway I would say heads and cam as well but it sounds like this guy wants some noise under his hood. If I were in this situation I would be calling up pro-turbo kits or fabing a turbo kit. I would get like a T67 or T76. Start out big in the beginning so you dont end up selling and upgrading later. Run 4-5psi on that turbo and you can probably hit around 400rwhp. Then in the future when you decide your ready for more power all you have to do is upgrade everything else and turn the boost up

good luck after its done and everything works excellent its fun, but sometimes that takes 4 years