How does your F5A turbo run? Mine's off & slow

MightyBoy tech questions and answers.
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BLSTIC
Posts: 51
Joined: Tue Jul 05, 2011 10:04 am

I've got an F5A dohc turbo in my 'Boy.

When I first got it it was idling at about 12" on my boost guage, and about 1000rpm on my *four* cylinder tacho. Max vacuum it could pull was about 19". It also smelled like fuel constantly and was running about 13psi

So I took the boost controller off and advanced the timing significantly. This gave me the ability to idle at 900rpm (same tach) & 14" once the idle bypass was adjusted. It can also pull around 22". Fuel smell has been reduced but still present.

The car is doughy, *never* pings, only really moves once it gets over 5psi (which doesn't really happen until 3000rpm on the tach, so 4000rpm, because with a 4cyl tach you need to multiply by 4/3rds), & until I get right up it isn't much faster than my F8B 'Boy. This is not what I've read F5A dohc turbo's are supposed to be like. It *is*, however, driving & idling smoothly for the most part.

Also my not-tuned-properly (aftermarket ecu) H22A honda idles at around 20" and pulls 28" or so on the over-run.

So I'm thinking my cam timing is out a tooth or so.

Can someone with an F5A/F6A dohc turbo tell me what theirs idles at (vacuum) and what the max vacuum is when backing off around 4000rpm? Or maybe someone with an EFI conversion?

Oh and how do you check the cam timing on these? Are there clear indicators? And is there a tdc mark I can use with the covers still on?
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