79corvette

I was looking around, and found a webpage about installin a turbo yourself. I started to look at ebay and found that Garret T3 turbos are really cheap. So, now I'm thinking of putting a turbo in. I wouldn't run very high boost at all. What do you guys think? I see though that a lot of the T3 people are using it on small engines, is it to small of a turbo for a 350. Just playing around with the idea, and then I can get that cool blow off valve noise :D . Thanks for the advice.

Monty

A single T3 is going to be a restriction on a 350ci engine. The largest T3, a T3-S60 trim, is only capable of 36lbs/min which means it is roughly capable of supporting around 360hp. But even at that high rate of flow the efficiency would be way down and it would be heating up the intake charge.

In the grand scheme of building a complete turbo system, the cost of the turbo itself is really a small part of the overall cost. If you're sincer about building a turbo system, I'd start with a more appropriate turbo to build your system around. You could, however, use 2 of the T3's with pretty good results, but I'd make sure they were at least 50 trim, if not 60 or S60. In eaither case, your 350 will spool them up very quickly and you would have absolutely no lag at all. With a single T3, the turbo would probably spool right off of idle whihc is not what you want. It makes for a very difficult car to drive as the increase in power in the 1500-2000 rom range would be significant and make the car "jerky", but you'd have no problem doing burnouts. Unfortunately, the turbo would become a bottle neck around 4000 rpm or so.

Good luck.

Matt Gruber

i like the turbo Neon- 13.6@106
get it and spank some c4c5's

79corvette

That thing is absurdly fast, but it's not a Corvette.


I'm not very familar with turbos, what are some larger ones than the T3?

Monty

I'd look for something based off of a TO4B or TO4E. They are pretty much the "industry standard" for automotive applications and there are a wide range of wheels and housings available for them. Most turbo's you get from Precision, Turbonetics, Innovative, ets are based off of Garrett TO4's. You can have a TO4 (TO4B-S-3) that would be comparible to the T3-S60 in terms of flow, compressor map and how much power it would support (~360), but a simple change of the wheel and housing and the turbo is now capable of supporting 700hp or more.

What is your target power goal and operating range (rpm)?

79corvette

I'd be happy with only around 400hp. I'm not going for crazy HP number right now, but in the future yes. I like to play around with things and figured a turbo would be fun to set up and install. As far as operating range, I'm thinking from 3500-5000rpm, or maybe a little lower. Is that a feasible rpm range? I'm just getting into the turbos now.

Monty

To be honest, you could more easily get 400 hp with simple heads/cam on your current engine. Much easier and cheaper than building a turbo.

However, with 400hp in mind, a TO4B-60-1, a TO4E-50, or even a T58 would work very well and would be very efficient (as much as 78%). The 60-1 and T58 would be good for 600-650 hp later one, while the -50 would only be good up until 450-470hp. Either of those turbos would work very well on a street car and lag would be virtually non-existant on a 350.

Doug2500

Monty

What is the highest efficiency you have seen on a turbo that would work as either a single or dual turbo system for SBC Vette?

79corvette

Thanks a lot Monty for the help. I'll start looking around for a TO4B-60-1 or a T58. I could live with 600hp. I like things that are challenging and different, not necessarily practical. I figure I can locate parts and slowly assemble it when I get them.

Monty

80% on the compressor side. Turbine maps aren't as commonly available, but the larger the turbine, the more efficient it is. While a larger turbo may take a little more exhaust energy to spool up, it will make boost at a much lower shaft speed than a smaller turbo. For example, a 60-1 like the one's I use don't start making boost until 46,000 rpm, and are most efficient in the 70,000-100,000 rpm range while a T88 will make boost at 33,000 rpm and is most efficient in the 45,000-60,000 rpm range.

Down8

Those aren't stock numbers (Dodge says something like 14.1). I've been a member over at SRTForums.com for months, and they were all glad to here it when someone broke into the 13s at 13.99 (stock). Now, once you add a boost controller (even the "$1 mod" they have going over there), you can get about 246hp to the wheels (Dodge under rated them any way, as they put 226hp to the wheels, stock), which gets you a bit closer to your number, but you'd need a great launch, which is hard to come by it seems (FWD doesn't help).

But yeah, for $20k, best deal around.

-bZj

Turbo-Jet

if you go turbo, you better convert to EFI. turbos and carbs just weren't meant to be. i'd love to design and build a turbo SBC with custom EFI such as something from Tech2 or electromotive. something mild like 500 hp would be cool.

Matt Gruber

that's the whole idea
the element of surprise
Still have plenty of work/fun to do, but
a 12 second neon would be my goal
More fun and has business potential too!