CFI-EFI, a few ?'s
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From: Hampton, VA Yea, i'm a redneck... but you love it
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CFI-EFI, a few ?'s
i have an '84 with the CFI. i also have a second CFI engine. i want to build the one not in the car up to about 400hp 450ft/lbs tq. is this possible? i want it to have that power, decent fuel mileage and it has to be reliable. also i am on a budget, but if i have to i can wait for the $$ to come in an then buy the parts, so that isnt too much of a problem. i have no time limit to get this done either.
any help will be appreciated
any help will be appreciated
Large Impressive Member
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
I'd go ahead and start planning your block build and look for some better heads. I'll let CFI-EFI tell you if he thinks the stock intake set-up can be modified to this level, or if you should look for something else up there too.
I'd also be thinking stroker for sure, especially considering the torque level you're seeking..
I'd also be thinking stroker for sure, especially considering the torque level you're seeking..
Drifting
Joined: Feb 2004
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From: Santa Maria CA
The CFI system even heavily modifed using a stock intake has never seen 400chp from anyone(that i've ever heard of). 400chp from a 406,X-Ram,bigger TB's,larger port heads,headers etc is about it. This is naturally aspirated of coarse.
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From: Hampton, VA Yea, i'm a redneck... but you love it
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thanks for the stroker info. how much power can i get out of my CFI with the external looking original? i also want it to be NA w/o NOS. i know bore & stroke, cam, ported heads, etc. also what does blueprinting mean?
Burning Brakes
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From: MD
A stroker is gonna be the only way to go. An Xram manifold uses the stock air cleaner and with the air cleaner on most people can't tell the difference. I would have to say that even with an ExtrudeHoned manifold (most ported you can get a stocker) that kind of HP isn't possible. MAYBE a stock manifold that's ported and siamesed could achieve that, but the tuning would be quite hard and I'd imagine driveability would suffer needlessly.
PS-Blueprinting means taking something and making it absolutely precise to the original specifications. Manufacturers have tolerances on mass-produced items and by taking the mass produced item and decreasing the tolerance (making it more precise) you get more performance out of it.
PS-Blueprinting means taking something and making it absolutely precise to the original specifications. Manufacturers have tolerances on mass-produced items and by taking the mass produced item and decreasing the tolerance (making it more precise) you get more performance out of it.
Large Impressive Member
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by Corvette for life
thanks for the stroker info. how much power can i get out of my CFI with the external looking original? i also want it to be NA w/o NOS. i know bore & stroke, cam, ported heads, etc. also what does blueprinting mean?
Also if funds allow, I'd consider a full neutrally balanced crank. This would also require a neutrally balanced flex plate or flywheel too, whichever is required for your application. The standard crank balancing for SBCs is neutral on the front half and externally balanced in the rear. This is less than ideal. Optimum neutral balancing and the lightest, yet durable components you can afford will pay ongoing dividends in overall efficiency, ability to rev freely and longer engine life, as well as minimizing parasitic HP loss. You may also want to consider maximumizing quench for some of these same reasons.
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Race Director
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From: The Top of Utah
Originally Posted by JLeatherman
I would have to say that even with an ExtrudeHoned manifold (most ported you can get a stocker) that kind of HP isn't possible.
Originally Posted by Corvette for life
i have an '84 with the CFI. i also have a second CFI engine. i want to build the one not in the car up to about 400hp 450ft/lbs tq. is this possible?
RACE ON!!!
Le Mans Master
Joined: Sep 2000
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From: Bartlett IL
CFL,
Ben 73 and Elkabong both have Xfires that are over 400chp. Each is using the Xram, and a 383.
Based on my 105mph trap speed this October, my 350CID/3500lb Xfire is pretty close to 390 chp. Its very definitely at 450+ctq. That's using a ported Xfire manifold that's been Extrude Honed. Each of these three motors has a different ECM than stock. Either an 8625(Ben) or EBL by Dynamic EFI (myself and el). Each of us do our own tuning.
Bottom line is it can be done. Anyone that tells you the Xfire manifold can't be made to perform hasn't tried. Takes work and time. Good luck.
Ben 73 and Elkabong both have Xfires that are over 400chp. Each is using the Xram, and a 383.
Based on my 105mph trap speed this October, my 350CID/3500lb Xfire is pretty close to 390 chp. Its very definitely at 450+ctq. That's using a ported Xfire manifold that's been Extrude Honed. Each of these three motors has a different ECM than stock. Either an 8625(Ben) or EBL by Dynamic EFI (myself and el). Each of us do our own tuning.
Bottom line is it can be done. Anyone that tells you the Xfire manifold can't be made to perform hasn't tried. Takes work and time. Good luck.
Last edited by Dominic Sorresso; Nov 19, 2006 at 10:20 PM.
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Team Owner
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From: Hampton, VA Yea, i'm a redneck... but you love it
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Originally Posted by Dominic Sorresso
CFL,
Ben 73 and Elkabong both have Xfires that are over 400chp. Each is using the Xram, and a 383.
Based on my 105mph trap speed this October, my 350CID/3500lb Xfire is pretty close to 390 chp. Its very definitely at 450+ctq. That's using a ported Xfire manifold that's been Extrude Honed. Each of these three motors has a different ECM than stock. Either an 8625(Ben) or EBL by Dynamic EFI (myself and el). Each of us do our own tuning.
Bottom line is it can be done. Anyone that tells you the Xfire manifold can't be made to perform hasn't tried. Takes work and time. Good luck.
Ben 73 and Elkabong both have Xfires that are over 400chp. Each is using the Xram, and a 383.
Based on my 105mph trap speed this October, my 350CID/3500lb Xfire is pretty close to 390 chp. Its very definitely at 450+ctq. That's using a ported Xfire manifold that's been Extrude Honed. Each of these three motors has a different ECM than stock. Either an 8625(Ben) or EBL by Dynamic EFI (myself and el). Each of us do our own tuning.
Bottom line is it can be done. Anyone that tells you the Xfire manifold can't be made to perform hasn't tried. Takes work and time. Good luck.
Le Mans Master
Joined: Sep 2000
Posts: 6,303
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From: Bartlett IL
Originally Posted by Corvette for life
can you tell me what else has been done on yours? i just want to get some ideas
http://home.comcast.net/~surrexi2/xf...Enthusiast.pdf
Overall, the Xfire is just a SBC with a different induction system. It responds to all the same things any SBC does. Cam/heads/headers etc. The heads and cam are matched. You start with the heads you'll be using and optimize them with a cam profile that complements the cylinder head flow. You understand you're using a Xfire manifold so this ain't no 7000rpm redline motor. And you work within those constraints. Don't try and make it something it isn't. One thing it does have it a sh*tload of torque.
The difference between this year and last year is a better tune worth 3mph in trap speed.
Last edited by Dominic Sorresso; Nov 20, 2006 at 09:22 PM.
