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ok got one for thought . I got a 84 corvette that I am just plain sick and tired of the crossfire injection system. it runs good maybe 3 days a month so im yankin it off. I just rebuilt the engine in the spring . but im thinkin rhs or afr 190cc heads with a healthy thumper cam , but I plan to use a 100-125 shot of nitrous . any ideas on combination? intake, carb, etc?? its a stock bottom end. thanx for any help
 

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ok got one for thought . I got a 84 corvette that I am just plain sick and tired of the crossfire injection system. it runs good maybe 3 days a month so im yankin it off. I just rebuilt the engine in the spring . but im thinkin rhs or afr 190cc heads with a healthy thumper cam , but I plan to use a 100-125 shot of nitrous . any ideas on combination? intake, carb, etc?? its a stock bottom end. thanx for any help
Have you given any thought to Pro-Filer 185's? They flow on par with AFR and cost under $1100 complete with roller springs and ready to bolt on.
SBC 23 Degree Cylinder Heads
A high-rise, dual-plane intake such as an Edelbrock 7101 would be my choice of manifolds, but may require hood surgery on a 'Vette.
 

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I can understand why you want to get rid of the "cease-fire" injection, they never were very good.

Thumpr cams are for poser's and mulletheads, there are lots better choices than a cam designed simple to make noise.
 

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ZZ4 shortblock, and get yourself a SY-1 intake and make a custom top out of aluminum plate...CrossFire guys love that. The CF isn't a bad idea, it was just limited by the days technology. An SY-1 with the ProFiler heads will make a pretty killer combo, if you cam it for the midrange. I would NOT hit an SY-1 with a healthy shot of nitrous either.

You better have some rear gear though; 3.50s at a minimum, and a hyd roller cam

What do you have in this for a transmission? You'll blow an 84 vintage 700r4 in a hurry
 

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I think you could also pull the ceasefire and go a single 2BBL TBI on an aftermarket manifold with adapter.
Youll have to check but I think the stock computer might run a single 2BBL.
 

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ok got one for thought . I got a 84 corvette that I am just plain sick and tired of the crossfire injection system. it runs good maybe 3 days a month so im yankin it off. I just rebuilt the engine in the spring . but im thinkin rhs or afr 190cc heads with a healthy thumper cam , but I plan to use a 100-125 shot of nitrous . any ideas on combination? intake, carb, etc?? its a stock bottom end. thanx for any help
The Crossfire TBI has the same potential as a 2bbl TBI on a conventional manifold excluding 454 and Holley 670 adoptions. A carb is a lot simpler and less costly solution in the long run.

I’d take the crossfire system off put it in a box and keep it for posterity in case you or the next owner wants’ to return the thing to original.

I like the AFR 190 head this is a very good head. I'd like to recommend the Comp XE268H cam but nitrous likes more timing put on the exhaust side so there may be a cam change with the NOS but those long exhaust durations on nitrous and blower cams are not a lot of fun without those power adders as they tend to over scavenge the cylinders of an NA engine this makes the mixture tuning kind of quirky and the gas mileage low. Doable but you gotta work at it.

I'd like to recommend the Edlebrock Performer RPM intake but that will have problems with the 'vette's low hood line, a low riser intake is a lot easier to fit and friendlier to the budget and hood lines.

For a carb; the ubiquitous Holley 750, it is not only effective but easy to work on with parts and knowledge available everywhere. You can even use the existing fuel delivery system by simply installing a bypassing regulator and dialing it for about 5psi at the carb. The bypassed fuel will use the current plumbing and will prevent the electric pump from dead heading during extended idle periods which overheats the pump as it depends on fuel flow though it for cooling.

This will build a very streetable engine in the very upper reaches of 300 horsepower at the crankshaft under 6000 RPM without even touching the laughing gas. With the AFR heads it can be tweaked for more than 400 but the low riser intake would have to go and along with a high rise intake will come a hood bubble, but 425-430 hp dyno crankshaft is doable with this combo and no giggle juice is needed. This of course depends upon the exhaust system which is never easy on these Corvettes. Obviously long tube of 1-3/4 inch diameter headers would be great, but fitting these is a pain, still the outcome is a lot less power absorbed by the exhaust system. This is the place where large amounts of power disappear between the numbers posted on an engine dyno compared to a chassis dyno. So attention to the exhaust system is important, even or perhaps especially, with nitrous.

Bogie
 

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Thoughts on the Weiand 8120 Speed Warrior? They used to have a slightly more refined casting than the recent Edelbrocks; Im not sure on the runner cross section and the height, but Im sure its lower than the Performer RPM.
 

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Discussion Starter #13
Thanx for all the replies its been awhile since ive seriously looked for a motor combo for this car .

I like the AFR 190 cnc heads with shaft mounted rockers. The flow numbers r impressive compared to others ive looked at .

I also agree with using a high rise verses the low rise intake manifold. hood surgery comes into affect but a 4-6" cowl will hopefully cure that problem.

my carb of choice is a holley 750 dbl pumper with mechanical secondaries . but im kinda likin the demon as well . have read a lot about them but don't know anyone runnin one yet.. kudos to oldbogie on the bypassing regulator . it makes sense to use one and it lets me keep the pump in the tank.

As for a cam in this mule ive been lookin at Comps NITROUS XP NX288XP sk kit to keep everthing in matching harmony. but im a little confused with the lifter choice for this setup as they give you options of different lifters to choose from??

As for exhaust ive always believed the bigger the pipe the better the flow. so im gonna do my best to squeeze 1 3/4 or 1/7/8 pipes down the side of it. ( one way or another).

The tranny im using is a proven 700r4, bulletproofed to 700 hp with a 2800 stall that a friend of mine built at our local performance shop. I haven't run it yet but his shifts beautifully with 600 hp in front of it.

The rear gear is a 3.73 sure grip posi (I think) with drag radials . I know its a posi but not sure on the gear.

im hopin this combo will get the car in the mid 10 sec range or better ?? my brothers '92 mustang runs a 10.73 and im hopin to send him back to the garage scratchin his head . thanx for all the help !!
 

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I have a C-3 and with my power I find it hard to hook . I will buy race tires next year.If I had juice the car would be worse,as it is I use a 6k chip to keep control on the street
 
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