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Discussion Starter #1
your stock heads,intake, displacement and compression ratio and cam are killing performance. the cross fire intake is the worst offender as it only flow about 170cfm-190cfm
swapping to a EDELBROCK SY1 with CUSTOM LID removes that resriction
THE EXTREMELY RESTRICTIVE STOCK INTAKE


custom lid SY1


compare the ports, the SY1 flows about 270cfm



<b>"A MODIFED EDELBROCK SY1 WITH CUSTOM TOP MATCHED TO 190CC AFR HEADS CRANE 114142 CAM -- AND add a 383 high compression engine kit"

b>
BTW Ill save you the math, youll need to get the 10:1 cpr flat top piston 383 kit for the street, and the 74cc combustion chambers AFR 190cc HEADS with L98 spark plug angles if you intend to run high test gas you find everywhere (some is lousy quality) and get the head gasket as close to .018-.022 as you can for correct quench
fyi DD-2000 and EA pro both guess at OVER a 115 hp improvement at the rear wheels, having done this type mod in the past Im reasonably sure thats UNDERESTIMATED for those listed changes

383 rebuild kit $1000
http://www.strokerkits.com/383.htm
crane cam/lifters $150
AFR heads $1200 http://www.flatlanderracing.com/cylhead_index.html
SY1 with custom lid $500-$600
DOING YOUR OWN WORK>>>>>PRICELESS! :thumbs: :thumbs:

offy
MORE USEFUL INFO

http://www.swko.net/~lionsden/crossfire.htm

http://www.swko.net/~lionsden/crossfire1.htm
 

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Discussion Starter #2
unless your rich or hopelessly masochistic get a SY1

the sy1 flows close to 270cfm out of the box, a cfi flows 170-190cfm (DEPENDS ON WHICH PORT (STOCK) and theres not enought room to port without cutting/welding (EXPENSIVE AND TIME CONSUMEING AND EASILY SCREWED UP)




these are the STOCK CFI INTAKE RUNNERS,

you can extensively port them
and its a big improvement over stock.............but they are still EXTREMELY RESTRICTIVE, and its not a huge help, if your looking to make significant hp


THEY WILL NOT SUPPORT A LARGE INCREASE IN HP WITHOUT MASSIVE CUTTING AND REWELDING WORK,WHICH COSTS FAR MORE AND WORK FAR LESS EFFECTIVELY THAN AN SY1 SWAP WITH A CUSTOM LID


this is the port work necessary to get them to flow even as pittifly as a TPI
 

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Discussion Starter #5
yes it fits under the hood,
no theres no EGR but any good machinest could get it installed
 

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Discussion Starter #8

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War Machine said:



DAMN LOOK AT THAT RESTRICTION!! :surprised :surprised :surprised

I bet that's no better than the V6 intakes of that era! :(
Thats what you get when you engineer an intake for the 305 and put it on a 350.......GM doesnt surprise me in ANYTHING they do!
 

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oldace84 said:
With the stock aircleaner....
thanks for answering my post....
tony

I've seen that intake before! :)

With the proper top plate the SY1 will work with the stock air cleaner as well aswith the stock fuel lines and cable linkage. The SY1 does require a small cap distributor. A 'plug and play' pigtail makes that relatively easy.




Adequate clearance is possible with the stock air cleaner.

 

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I ran an sy-1 for a short while and was not happy with the hood clearance. Even after removing the TB to filter enclosure gaskets and also removing the rubber seals inside the filter enclosure, it would still mark the underside of my hood....

I'd like to try it again, I ust have to find a few more mm..

As it is i'm running an xram and ran a new best of 12.48 at 111.6mph just this week :devil:

I know the sy-1 would be better...
 

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Discussion Starter #15
"Can a 383 stroker be used on a Crossfire '84?"

sure I know of several doing it now
 

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383 stroker

I was thinking about doing the x-ram since they don't make the sy1 anymore. I dont have much money. just put a side exhaust on it. how much would the 383 cost and how much hp would i put out?
 

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Discussion Starter #17

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wow

wow. that is a lot of gain AND a lot of $$. do you have any ideas for something around 1500? o yea i definatley dont know how to work these posts and replies haha
 

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Discussion Starter #19
THE OFFY base IS STILL CURRENTLY MADE, and can be adapted



http://store.summitracing.com/partdetail.asp?autofilter=1&part=OFY-5893&N=700+115&autoview=sku



http://store.summitracing.com/partdetail.asp?part=OFY-5902

http://store.summitracing.com/partdetail.asp?part=OFY-5903

the basic crossfire manifold is a HUGE restriction EVEN if ported to the max, the XRAM is nothing but a single plane carb intake with a mickey-mouse adapter to allow the TBI injection to be bolted on.

read thru this

http://www.swko.net/~lionsden/crossfire.htm

either the OFFY or the SY1 intake base, with a custom top plate will be a HUGE improvement, easily able to support 500hp or more on a correctly configured engine with decent heads like the AFR 210cc or AFR 195cc

http://www.airflowresearch.com/210sbc_rh.php

and a decent cam like this crower

http://www.crower.com/misc/cam_spec/cam_finder.php?part_num=00404&x=25&y=17

installed in a 10.5-11.0:1 cpr 383

but keep in mind youll need a 3000rpm stall converter and 3.73:1 rear gear to run those
keep in mind INTAKE HEADS AND CAM and COMPRESSION ALL must be upgraded to get full flow into the heads , so that the power levels your looking for can be achieved,and the stall and rear gear must be changed to use the significantly higher rpm power band effectively, but theres no comparing the results after the mods are correctly made, youll have well over 140 plus MORE hp,(plus) if you do things correctly
 

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DC Crew
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Thanks Grumpy.

I just watched the end of a SY1 bid go for $316. Been reading your CFI threads the last day to give the info to another Vetter. I'll let him know about the kit on Summit too.

:thumbsup:
 
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