Hello everyone. I just moved up to a 3b in my bj40 (from a B) and I brought my turbo with me. This new engine seems to be in great shape, and I’d like to do everything in my power to increase its lifespan. Only thing I’ve played with so far is the fuel. I did on my B as well, and was always chasing egt temps…eventually I’m going to run a water to air intercooler, but not for a few months at least. Someone told me it would be wise to dial in my injection timing now that this 3b is running a turbo. Can someone shed some light on this? The pump is currently on the factory timing marks on the pump/gear case. I’m running 12lbs of boost at the very most when on the highway, and my temps are manageable, but I’d like to lower my numbers to something more conservative and safe. Would appreciate any input, thank you!
You need to retard the timing as the boost from the turbo increases the compression and can cause early detonation.
It probably won’t help lower your Egt numbers but it will help keep unnatural forces off your crank.
For a non Intercooled 3b 12psi is pushing the egts high here on the hilly island and rest of BC from my experience.
I recommend a small low rpm spooling turbo with a wastegate and keeping the boost to under 10psi. Or intercooling it and still only making 12psi or you will run into heat issues on those 5 kilometre 6-10% hill climbs.
Also something important of note I feel is I did some testing on the 60 series that has a larger intake for the factory air can than the 40 series and I was pulling a vacuum in there under boost so I upgraded the air box inlet.
One random day the thought occurred to me that my non intercooled turbo 3B might not be getting all the air it could use at full send threw the stock air cleaner.
Conveniently I found my air cleaner lid had this nipple I never noticed before seemingly perfect for this test.
A carburetor vacuum gauge slipps right on
Top picture at idle, bottom picture is anything over 1600 rpm. So I’m pulling around a 1/2 psi negative pressure threw the stock air cleaner at anything over 1600 rpm.
