Newbie here all. Having a custom 383 being built for my truck. But right now my main issue is in rebuilding the tbi pressure regulator. Yes it has been chipped. Upon disassembly of the regulator there was a spacer used under the diagram..... To increase/decrease pressure not sure. Seeing the regulator is unadjustable. Any thoughts? The spacer is far left old diaphragm middle new right. Should I put it back in?? Will discuss motor specs soon. Thank you
Greetings Taz069,
1) Given that you are putting together a 383ci SBC ballparked at 425/425 with ? pistons, ? cam, ? heads,
etc., it sounds to me that you are a perfect candidate for an adjustable fuel pressure setup per Schurkey's
comments above. Failing that, possibly an aftermarket setup like these Marine guys offer? (LINK)
2) In addition to an adjustable fuel pressure regulator, maybe you also need to increase
the lbs/hr rating of the injectors that you are going to use?
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(Credit: Craig, one of those detail-oriented dudes over at the International Harvester parts website?)
3) Given the HP/Torque numbers you are expecting to make, these seem to overlap what
the TBI 454ci trucks were making? (At least the torque specs, anyway.) If this is what your
engine guy is really putting together for you, then instead of the original 350 TBI setup
becoming a potential pinch point, why not go from the original twin 1 11/16" bore size
up to the 2" bores (& matching 80 or 90 lb/hr injectors) that came with the big block?
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It sounds like you are putting together a nice powerplant. If you are going with a 'chipped'
computer purely as a starting point & you are going to dial it in from there you should be
able to have the best of all worlds. (ie: More power/torque + factory driveability/manners.)
On the other hand, if your 'tuner' is going to handle getting this dialed in remotely, this could
take several iterations to getting it right. Perhaps one of the TBI tuner gurus in this forum
could share their experiences on what they did in your situation.
FWIW --
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