I’m an old school no replacement for displacement guy. I’ve worked on big diesel trucks and equipment so I understand the basics, but I want to learn about turbo charging small blocks etc. I’ve gone the google route and done a bunch of reading, but I find most threads are all conflicting. So how do I, or how did the people on here that seem to have become pro’s at it, learn it all? I’d rather not be picking up pieces of piston on my garage floor if I can avoid it.
Go easy on me, everyone has to learn somewhere. Links? threads?
My only turbo experience outside of the diesel world was on a honda. nothing really to learn. just kind of bolted on junkyard parts and got a base tune on a chip.
So I’m as rookie as it gets.
Easiest way to learn is to do. turbocharging a small block has been done thousands of times over. From what ever combo you piece together, finding a safe level of boost to run with that combo is just a few web searches away. You don’t have to reinvent the wheel. Plenty of good info out there.
Dont go for ambitious levels of boost on stock engines. I turboed a taurus sho and apart from transmission issues it made good power but i cracked a piston running too much boost. 15 to 17 psi is too much for the stock ring gap on that particular engine and caused a problem.
Assuming you are going to do an EFI motor, you will need more fuel (injectors/fuel pump), turbo, exhaust manifolds, wastegates, downpipes, charge pipes, bov, intercooler, programable ECM and some sort of boost control. Most likely you won’t be pushing your first setup too hard and with a motor with such great displacement spool won’t be too big of issue. All that means is you have a decently wide range of turbos that ‘will work’.
Getting the mechanicals setup is the easy part, if you have any basic fabrication skill and understand how the system actually works. Tuning can be more of a black magic, if you are new at it. But with todays tech it really is not that hard, using a widerange sensor and gauge, an EGT gauge and as long as you start with low boost and work up slowly you should be OK.
As a ROUGH guide for the fuel side of things you want stoich everywhere you have decent vacuum and as you get more load and start flowing more air you want to go richer to a max of around 11.5 if you are running 93. If running E85 the larger quantity of fuel injected (less power dense) will cool the charge better and therefore you can run leaner, aim for 12 to start.
The other side of things is timing. That is largely dependent on you motor/heads plus fuel used and other hardware. I’m sure there are many examples of timing tables for iron block chevys all over the internet. That can be a blessing and also a curse because now you are trusting some random stranger, on the other hand it can help you get a decent idea of trends and at a minimum a starting point. Basically your goal is to get to MBT. Timing for max brake torque. This will not be possible to do at all points, because the increase in heat and cylinder pressures resulting from turbocharging. If you have knock sensors you can use those as a guide, but this is where your EGT gauge will come into play. Start with very little timing and keep increasing until your EGTs are at an acceptable level. More spark advance will cause EGTs to go down and will also make more power. But too much timing and you can begin to knock. Detonation on a boosted motor can be much more catastrophic than on an N/A if its bad enough so once again take it easy.
I’m not even sure if any of your questions even pertained to this but I really have just scratched the surface. All of what I have said is just from my experience with this stuff, it all might not be 100% applicable to your setup but it give you an idea.
I would highly highly reccomend using efi over carbs, the resulting tuneability is crucial to making the engine last especially stock and especially on pump gas, and it helps to tune conservatively instead of trying to wring every last hp out of the engine by tuning aggressively. When I started getting into custom turbo setups, I read Maximum Boost by corky bell, lots of good info there and I’d highly reccomend reading it if you want to build your own setup. Turbos are a great way to make serious power; easier on the engine than nitrous, easily more efficient than supercharging…
