Does anybody know anything about changing my Fbody to a Carb setup?
All info is greatly appreciated.

BC

 

i know if you do it, your gonna have to lower the motor anytime you wanna take the distributer out. alotta fun there

 

If you don't want to go there please disreguard my question but......
Why do you want a carb?

 

Yeah you have to convert over a SBC intake it start with since the GM LT1 dual plane is not worth much if you want it for a race car.

That and the distributor are the two biggies, really only needed if you want to go drag racing.

Bret

 

Even drag racing the only reason I see to do it is if you need to spin over 7200, the limit of the stock pcms ability to control spark.

Do the Gen1 intakes match up to the ports even vaguely well?

 

I just changed my cam and I found out why I was only getting 8-10 mpg.In lieu of buying new injectors,opti,computer it just makes sense to me.I have raced using carbs my whole life and I know much more about it.Also my friends seem to have ign. and Fi problems all the time.
The biggest factor is I'm not going to be driving my car on the street anymore until Prem goes down to $1.50 a gallon or hell freezes over.
I also have a Chuck Nuytten 750 that I paid $1300 for and it's just sitting on the shelf.It works great at the track and on the street.

BC

 

im runnig a carbed LT4 motor and that GM intake has ALOT of material to port match it to the heads...i DID NOT port match mine to my stock LT4 heads..with a stock cam and long tube headers i put 3 cars on a 6 spd LT1 to 80...like i said, theres ALOT of material for port matching...BTW GM states that on a stock motor there will be an increas of around 20 ft pounds down low and 15-20 top end ponies...not a lot of people run them, but they DO FLOW VERY well....porting and matching will yeild greater results...


this motor is also in a GTA so the cowl isnt an issue with mine, but i know there isnt a lot of rom under there, but i also know that if the cowl has a notch cut out of it then you can R/R the distributor NP

 

I've always been told that a dual plane intake is better unless you are going to be turning over 7500 with a 6000 converter.
What RPMs are you turning your car?

John

 

How well does a carb moderate AFR from 12.5 around peak torque rpm to more like 13.0-5 at peak HP rpm, plus the opti is a hell of a lot more accurate than an HEI just due to the short powertrain. I know some people think carbs make more power but honestly I don't see how.

Why injectors/opti and pcm, injectors can be had for less than what the new intake will cost, then trade the cost of the opti rebuild against the cost of a low pressure regulator. Got a HEI on the shelf too? Honestly sounds like you are looking at spending the same amout as if you just fixed what is wrong, if anything is wrong.

 

First I'would never consider runing an HEI.I'm going with a Crank Trigger with a gutted dist.Secondly,A low pressure reg and fuel pump is about $75.I can buy the intake for about $225
With the crank trigger I will never have to take the dist out.
I own a Temp reader that installs in the header and you can gauge the air fuel ratio by the exhaust temp wich is all the O2 sensors do.
I'm sure I'll hit some roadblocks but remember this car is not going to be driven on the street.And since the LT1 intake is just a wide open box the carb intake will give a more direct even flow .

I'm not trying to take anyone away from the LT1 setup.

John

 

Nice Carb

I've found on street cars that make good HP that they are fastest with a good single plane intake. 7500rpm is not needed, in fact the better A/F ratio mix along with the longer more equal runner lengths is going to be better on a street car.

Bret

 

mine is a stick and it pulls all the way to the 6000 rpm revlimiter,..i usually shift at 5,800 or 5,900 hundred






i agree with that...generally speaking, when guys put a H/C package or what not, there gonna do a convertor...and a dual plane would not be of mush use, becasue the stall will probly be higher then the power they gave up down low...but for more mild motors you "NEED" that off idle grunt....i mean from a rolling idle in first gear if i hammer it it will instantly blow the tires off it...theres no way that would happen witha single plane...

 

Yeah you can. Low RPM is not all about the intake, there are a bunch of other things that make the lower part of the RPM range "Torquey" and why would you want to loose traction anyways? That doesn't make the car fast, getting more TQ up high is what makes the car fast.

Look at any of the small blocks or big blocks in the Engine Masters Challenge, any of them that did well used a single plane intake, and they have to pull WOT at 2500 with a carb.

Bret

 

its not that hard to switch, and a good tunned car is much more powerful on topend in my opinion...i live in such a remote area that its not very practical to haul my car 6 hours to have it dyno tunned by someone...whoever said its eaier to tune with LT1 edit than it is to simply re-jet your 4150 holley must be very familiar with the software and system...im no idiot, ive built rods since i was a wee fella, but i can say this...the dual plane intake offered by chevrolet has flow characteristics very similar to the lt1 SFI intake...very similar powerbands...and as far as dual planes vs. single planes...a good large plenum dual plane is much better in the 6500 and below range than a single plane...and if you really need options simply have a sheet metal tunnel ram built for your LT1 and use a solid cam...then what can the EFI guys say???...i can tell you this from MY experience, i had 2 different very well known shops try to make a PCM with no luck...i have had 3 optis go out due to overheating, moisture...etc

call me the moron or the one that goes against the grain but hey it seems more natural and easier to tune my fuel system with a screwdriver than a 1200$ laptop that i dont own to begin with...

and for all those that say the injection is so wonderful and so easy to tune why is there 2 LT1 intakes made by edelbrock for GMHP plus the many fabricated ones running around now, not to mention the new carburated intake for the LS1???

come on! no one would produce these parts if there were no desire for them or if the injection/ignition was bulletproof

whoever is tired of optisparks and injectors that pour gas out the tailpipes when you stop, and being left at the mercy of a 600$ dyno tune or a half/a$$ mailorder and return/retry program...lets get a group purchase on some 750 mechanical carbs from holley and give the injectino to the ones that believe it belongs on a REAL racecar

 

Is there a site where I can find to do this?MSD told me their crank trigger wouldn't work on a computer less LT1.I have a very good carb just sitting around.When I ran Superstock I ran nothing but a crank trigger.

Any help would be greatly appreciated.

John