Hey I've got an idea. I want swap a Crossfire setup into my 91' Rs 305 TBI. I know you all think I'm crazy, and I am, so don't bother sayin' it again. I'm not stupid, I already know that I wouldn't get anymore power by just bolting one on. I intend heavily modify the setup for better flow ( I know how restrictive the intake is, have some ideas ). But I do have some questions though. I know there has to be someone just as loony as me who has already done this swap. I know I need the all of the obvious pieces, but what about wiring and stuff. How about the ECM? If remember right the ECM is part of the reason CFI sucks so bad from the factory. Could I use my orignal wiring and ECM with a custom prom maybe? CFI only has one throttle position sensor and fuel pressure regulator. Will my serpentine belt setup still work? How about emissions? I live near Houston, the treehuggers are starting to get their way, so I need to keep AIR and EGR. Which air tubes should I use? I plan to run TPI exhaust manifolds. I'll have to move my remote coil right? Is their a place to hook up my TV cable for my 700R4? I'm also curious are their bigger TBs that can be tweaked to fit, I know the stockers flow poorly ( or can porting and polishing get them near 600 cfm combined ). I looking to use as many factory parts as possible ( don't mind tweakin' them though ) cuz I'm cheap ( college student ). I any help or guidance would be very much appriciated ( short of tellin me about a nice padded room just for me ). Sorry about the long post, thanks for the help.

 

Oh yeah, if you have any ideas about mods that would help please post 'em. Lookin' about 275 hp ( total, not just from CFI swap, lots of other mods planned ).

 

Want info on the crossfires? Check this place out!!!!

http://www.crossfire.webhop.net/cfforum



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Dan

 

Update: now have nearly complete wiring harness from 82' Z28. It looks pretty crude> Can I splice it together with a later and more advanced TBI harness ( and use newer computer ). Anybody have a diagram of this Crossfire harness? It would help a lot, don't even know what most of the relays do, but made sure I grabbed them.

 

Why is everyone making their lives so fricken difficult on this site? people wanting dual exaust for no reason, crossfire TBIs, turbocharged stock L03s, dynomax headers with no Y pipes....

Heads, cam, and exaust are your main restrictions, not the TBI and intake. Once you do the others, THEN the TBI becomes the restriction.

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-Tas
'89 Formula WS-6

305, TBI, 700R4, P.A.W. 14x3 open element with K&N, Milodon 160* thermo, functional Formula hood, cross-flow Flowmaster, '99z28 rear pipes and tips, Hooker 1-5/8" 50 state legal headers, Dynomax 3" I pipe (PN 44063 and 43248)
Super GRK_Taz World
F-Body Dual Exaust
EFI & Intake Options


[This message has been edited by Tas (edited November 11, 2001).]

 

well tas, the crossfire set up is actually capable of making more power than a stock tbi. it can move more air at a higher velocity than our stock set up can. which means, not only will it make more power, but it will be capable of getting better mileage and having lower emissions, which are the 2 reasons gm started using tbi in the first place.
as far as the other restrictions you listed, teh swirl port heads aren't desired technology but htey will not hold back any set up with a stock or mild cam much. all the stock exhaust really needs is a y-pipe and it will be good to well over 200hp at the wheels. and even the stock cam can make plenty of power to be quick, as i have proven.
the only thing that cfi really has against it is that there has never been a major effort to produce specific parts for it, namely a manifold the will allow for higher rpm power.

later
tim




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91 Camaro RS-LO3,Auto
New Times Coming Soon!
Check Out The East Coast F-Body Nationals Home Page
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My MAFB.ORG Home Page
www.mycar.net/mafb/registry/detail.cfm?id=299
DSI Racing Home Page
www.geocities.com/foff667

 

If I were going to use crossfire to make 275hp I would HAVE to get into custom eprom burning. I would keep it cheap so I would keep my TBI ecm and just fool the ecm into thinking the crossfire is a TBI intake. Crossfire is TBI, except the crossfire is a little more unconventional = cost more from factory. TBI has 2 injectors, so does crossfire. Crossfire has one advantage, they have slightly larger injectors (from the 350 corvettes!) at 67# compared to the 350 61# and 305 55#. The advantage of using your current TBI ecm is that you won't need to replace any sensors, no wire splicing, nothing. If you go to the diy-eprom board, ask there and I'm pretty sure 'Grumpy' will have a good idea. He's the only guy other than Joby (supercharged crossfire vette) that I know of that has experience with the old TBI system.
It shouldn't be hard getting it to run right. Think about it, the system is just a TBI system with a funky intake and 2 single TB units.

Edit: Let me also point out that TBI uses peak and hold injectors, they're the SAME between crossfire and TBI! So why wouldn't you want to just run it off of your current TBI ecm?

[This message has been edited by JPrevost (edited November 11, 2001).]

 

A lot of Cross-Fire users are changing the stock ECM's (1225550, 1226026, 1226430) to the newer 1227747 from GM TBI trucks.

Main reson for doing that is to be able to create custom eproms. The stock Cross-Fire ECM's have not been hacked yet.

It should not be more difficult to make the Cross-Fire intake work with another TBI ECM.



------------------
Jonas Bylund

 

All right, keep those ideas flowing. This helps a bunch. Yeah, I like the idea of using a later TBI computer. I always heard stock ones are crummy. Turbo City wants $500 for a recalibrated one . I would like to find a another stock TBI harness and splice it together with the Crossfire harness I picked up. I think most of the CFI is crap because is looks pretty crude compared to my 91'. I think it would be possible to just use some of the CFI connectors and the longer injector wires on the TBI harness. Could my Camaro ECM work with a custom PROM? If not, only the trucks, what about LO5 Caprices?

 

What I would do: Keep existing TBI harness and just make the leads for the crossfire injectors long enough to get to each injector. That's all you would have to do! Everything else stays later TBI.
Next I would keep the 8746 ecm (came in 89-92 f-body and 89 caprice cop car w/L05). If you need the Lo5 eprom let me know through e-mail since I don't know where else you'd be able to pick them up.
Where you going to put this on a 350 or a 305?

 

I am putting it on my 305. I planned to just splice on the longer injector wires and the TPS since it might be different off the CFI harness. But it looks like the CFI TBs have a few more sensors on them? I still have my stock LO3 computer, but I know where an LO5 one is if I need it. Do you think the car will at least run with the stock PROM? Oh yeah, when I get this setup on, the car will have an LT1 ( or LT4 if it wouldn't overcam the motor? ) cam, TPI exhaust manifolds, hi-flow y-pipe and 3" cat, and 3" catback system. I also plan to upgrade the ignition and fuel system. On the right track? I also have an idea for the manifold. I saw that the ports are much smaller and can't be opened up because their is a water passage their that is meant to warm the incoming charge. Could I fill the passage with water jacket filler and then port the intake out to normal size? Finally, I plan to rebuild the motor at 200,000 miles ( its at 160 now an goin' strong ) and add 305 Torquer heads and nitrous ( stronger rods and pistons for this too ). This will probably require a totally custom chip right?

 

Couple other questions. The CFI TBs run in series right. Only one TB has a fuel pressure regulator and the injectors are different sizes, right. How tough would it be to run them in parallel? It seems like I could put a T fitting in the fuel line and run it to both TBs ( both with the larger injectors ) and then run the 2 return lines back into one. Would I need two regulators? I also heard from a friend that their is book that is all about CFI engines, have any of you ever heard of it?

 

It is possible to run them in paralell and use an external fuel pressure regulator. You don't even have to modify the stock regulator. Just open it up and lower the fuel pressure setting (it is adjustable if you open it up). Just make sure that the external regulator have a higher fuel pressure setting than the stock one.

------------------
Jonas Bylund

 

Hey Dan, Joby,

Why can't I get on to the new CFI Forum? I clicked on the link in the post above, and I get and "access denied" page. Do you know what's up?

------------------
'83 Trans Am: 400 CID oil burning junkyard long block, 224/234 crane cam, Summit aluminum roller rockers, hand ported intake, home bored 2.09" (53mm) throttle bodies, MSD 454 injectors(75 lb/hr), Holley 255LPH fuel pump, custum modded FPR, Edelbrock TES headers, SLP 3" stainless steel cat back, stock ECM & chip. Borg/Warner T-5 World Class, 12" Corvette rotors and clipers, GTA 16" wheels, South Side Machine subframe connectors, 1LE sway bars, 3.45 ring and pinion, Alpine sound.
Best E.T. 13.257
Best MPH 105.24

 

It works for me.

Did you sign up again? The old user / password does not work until you sign up again. You must also log in to see the forum.



------------------
Jonas Bylund

 

How do you log in? I just keep getting a page that is mostly white w/text that says ERROR
The request for the URL could not be retreived.
The following error was encountered:

-ACCESS DENIED
Access control configuration prevents your request from being allowed at this time. Please contact you service provider if you feel this is incorrect.


There is no place to log in. Do I need to clear my cache or something? I'm lost.

[This message has been edited by Tom 400 CFI (edited November 12, 2001).]

 

So far the wiring for this doesn't seem bad at all. Tuning I'm sure will be a pain. Is their I book or something I can get to help me understand how to burn custom chips, I know how fuel injection works, but you guys use some terms when talking about tuning that have me scratching my head. Also, what do you think about my serpentine belt setup? It looks like I'll have to modify the upper compressor/idler bracket since the CFI manifold is taller. I think I'll have plenty of hood clearance, but what about an STB ( have a nice twisty 'vert )?

 

What do you think is a reasonable price for a decent CFI setup? Note: I want this topic to stay open, please don't post try to sell me one on here, e-mail me. Thanks.

 

Should be able to get one for about 100 -150 on ebay.

 

Hey about some manifold questions. I know the stock CFI manifold is a fairly rough casting and that everybody at least polishes the inside. What are those little swirling things under the TBs good for, do most people just cut 'em out? How about the EGR passage? Will cutting the passage out and disabling the EGR mess up the computer? I've also noticed that the ports are smaller, and very small at the end. I've seen them opened up quite a bit, does ruin the port velocity, or is it still worth it. It doesn't look like you can go too far because you'll go through the bottom of the manifold. It looks like filling the water passage ( if possible ) would only help keep the charge cool, cuz it would do no good to port this area out, at least past a certain point, because you can't port too far once you get closer to the end.

 

i opened up the runner ends, tossed the swirl plates, cut out the egr, and polished the entire intake, with good results

------------------
1984 Z51 Auto, Ported and polished intake, K&N, MSD, Ram air/Cold air intake, no cat, no AIR, no egr, no swirls plates

 

Hey Tom, Marck (Twinnie) here.

You probably can't get into it because it's being rerouted over port 81 (instea of the normal HTTP port 80). This is because Ken's ISP blocked off 80 for dynamic IP's (people hosting stuff on servers at home via cable).. contact Ken, maybe he can set it up on another port 98080 or 8010 or so)..you'll get a new link http://www.crossfire.homeip.net:8080
(the webhop thing does this: http://www.crossfire.homeip.net:81 )

You can email ken at ken73@ken73.homeip.net (email comes through, it goes through another port)

This sucks man, you're the 2nd one that can't get on. The old forum blew up and is rendered useless. (all mmbers profiles were gone, and you couldn't re-register for some reason)

You could also ask your ISP to allow surfing port81 for that one page. If they feel it's safe they will probably let you!

Marck

[This message has been edited by FAQman (edited November 14, 2001).]

 

So what will disabling the EGR do? Will it confuse the computer? I thought I will leave it all looking functional on the outside, but I what to cut the passage out of the manifold.

 

Dis abling the EGR should not affect anything. Mine has been disconnected for years, with three different sized engines sitting under the CFI, and it has always run well. Sould be no problem at all.

 

what you want to do is cut out the egr channel, but you need to be careful that you dont cut into the exhaust passage, other wise exhaust will be in the intake all the time
http://www.crossfire.webhop.net/
look under the tech articles..there pictures of how to modify the intake. People have been knocking 3-5 tenths of the 1/4 just from porting the manifold. With all my mods i've gone from 15.1 to 14.3

------------------
1984 Z51 Auto, Ported and polished intake, K&N, MSD, Ram air/Cold air intake, no cat, no AIR, no egr, no swirls plates


[This message has been edited by nsimmons (edited November 16, 2001).]