HP capacity for TBI

I am building a 383 stroker for a 1990 PU , planning on about 300 to 325 HP,1000 to 3000 RPM power range. Will the stock TBI flow enough fuel ??

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Depends on what engine the original TBI came off of.
Doc
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It is a 1990 Chevy 1/2 ton 350 CI and I am going to rebuild the original engine
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engine
You need a modified PROM for the ECM and <might> need bigger injectors depending on how hot you make her. It is very hard to make a 300HP 383. You'll likely be in the 350-375 range.
Doc
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You will have to seriously de-tune that 383 to make only 300-325 hp. My 383 project is mild and will make roughly 425hp and 450ft.lbs. of torque at 4500 rpm, if the TBI came off a 350 cid motor it will run the 383 but you may have some severe driveability issues. I am building a long-rod stroker that won't see anything over 5500 rpm using a hydraulic single-pattern roller cam and 1.6:1 roller rockers with Vortec heads, 1 5/8" hedders, Torker intake and 750cfm Edelbrock Performer Carb. Keep in mind that my engine is mild because i'm utilizing the stock torque converter and has the potential to make over500hp on pump gas. I believe you're underestimating the potential of that motor by a wide margin. do your homework brother, this is my 2nd big money Chevy i've built and i learned the hard way that it's very easy to build a motor that is un-streetable when using a hydraulic flat-tappet cam with 312 degrees of duration and .528" of lift. This hydraulic street-roller cam only has 270 degrees of duration but will make over .500" of lift using 1.6:1 rockers........easy on the duration, heavy on the lift.
--
Mad Dog

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Thanks for the info, but my only question is, will the stock TBI system supply enough CFM to feed a 383 CI. I am still happy with TBI system, I will be adding a Edelbrock intake manifold, Edelbrock aluminum heads, my current JBA Headers. Where I live most of the time we can only get 87 OCT, the tranny is the 700 E and the rear end is a 10 bolt. Don't need or want 500 HP But thanks for your feed back.
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Yea, but you may have some driveability issues since the factory cal-map is programmed for a stock engine.....in other words, it's gonna run lean. -- Mad Dog

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I am going to get a new chip burned when I get all the engine spec's, so the suggestion is larger injectors in the stock TBI is that correct
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On 12 Jan 2004 18:07:52 -0800, snipped-for-privacy@yahoo.ca (pedro) wrote:

the injectors from the 454 (7.4l) should flow plenty of fuel, if they are marginal (for your application) you can also use and adjustable fuel pressure regulator and bump up the pressure..... more pressure more fuel flow.
-Bret
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snipped-for-privacy@business.net says...

The injectors can flow all the fuel the throttle body can handle for it's CFM rating. If you aren't going to get enough fuel, then you aren't going to get enough air, either. So putting the entire higher CFM unit from the big block would be the way to go if that's what's needed. What I would suggest the original poster do is look up the horsepower and CFM specs for the Edelbrock and Holley aftermarket units. If they are higher in CFM than the stock units, you may want to consider the larger TB. Intake manifold may now become an issue in terms of flow, but I know Edelbrock has an aftermarket manifold for the TBI's.
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