I have a set of RC Engineering 550's I'd like to go ahead and install, but I can't find which combo to use. I found a couple posts of people running them with the SFMU but no info on the discs they used or what psi to set them at. I do have a SAFC to lean them out if needed.

Hahn Stg 2/SFMU 8psi(going up to 10psi once I finish the Greddy boost controller wiring)which I'm well aware is a risk on stock internals lol. Also installing a ported/bored IM/ MP 60mm tb and high flow fuel rail. The MS and Aero 1:1 will go in sometime next month(need to order more fittings)

Stock internals at 10lbs = blown ringlands. I should show you a pic of the ones I pulled out of my boosted 420a on stock internals. But if you want to rebuild soon then go ahead. just my 2c.

It will be rebuilt soon enough, just need an excuse lol :P

Originally posted by eclipserstturbo
Stock internals at 10lbs = blown ringlands. I should show you a pic of the ones I pulled out of my boosted 420a on stock internals. But if you want to rebuild soon then go ahead. just my 2c.

Many members here have ran 10psi for years on stock internals.

Originally posted by eclipse982nrRST

Originally posted by eclipserstturbo Stock internals at 10lbs = blown ringlands. I should show you a pic of the ones I pulled out of my boosted 420a on stock internals. But if you want to rebuild soon then go ahead. just my 2c.

Many members here have ran 10psi for years on stock internals.

ya. the lucky ones.

Im hoping you have a wideband o2. I have never ran 550s, but I ran 440s for almost a year before upgrading to MS. I was running the 3rd largest disc and idle pressure was set around 20-25psi. You should try running the smallest disk or maybe the next to smallest disc. Set idle to around 15psi and pull the rest of the fuel out with the SAFC. You dont want to lower your idle pressure any lower or the fuel wont atomize correctly.

You can get a ball-park feel for the pressures you need by running through the fuel system design stuff: http://www.2gnt.com/index.php?d=Fuel%20System

Use the S-AFC sparingly. Try to do everything with the rings and disks in the S-FMU and use the S-AFC for fine tuning. Lowering your MAP sensor output can make the stock ECU advance timing. I was knocking like crazy trying to tune my car with 440's, S-FMU, and S-AFC. I was never happy and got rid of the setup within a few months.

Corbin
'95 ESI-T

Now with more power and fewer leaks



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