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I know im gonna hear about it from the purists, but Ive messed around with this SD conversion mess someone else started. Ive got it running, its on the 3rd custom prom and it just keeps loading up. Runs hard when wide open, but still not right.
Nevertheless- Im not gonna waste this whole season messing around- I wanna drive it, so Im switching it over. I have everything to do it. I'll have it done in a day or so once I start. My question is for anyone who has done this.

How does yours run with the carb? I hear they actually will RPM better and run through the midrange and up top stronger.
Best intake manifold ? I have a used performer I was gonna use because of hood clearance. Id rather run an RPM. What have you experienced ? Thanks.
 

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I know im gonna hear about it from the purists, but Ive messed around with this SD conversion mess someone else started. Ive got it running, its on the 3rd custom prom and it just keeps loading up. Runs hard when wide open, but still not right.
Nevertheless- Im not gonna waste this whole season messing around- I wanna drive it, so Im switching it over. I have everything to do it. I'll have it done in a day or so once I start. My question is for anyone who has done this.

How does yours run with the carb? I hear they actually will RPM better and run through the midrange and up top stronger.
Best intake manifold ? I have a used performer I was gonna use because of hood clearance. Id rather run an RPM. What have you experienced ? Thanks.
From what I have heard,
Edelbrock Performer RPM wont fit or clear the stock C4 hood with a Holley 4-barrell, Edelbrock, or Rochestor Q- jet.

It may clear with a drop base style air cleaner such as made by MOROSO, 14" diameter air cleaner.

Performer Intake is a perfect fit.

Cutting a hole in my hood to fit my Intake & carb.
Not scared or worried.
Have a hoodscoop in mind.

I think the C4 85-89 MAF system is superior to the C4 speed density system come 1990.
On the street only for daily driving.
Exception was the 1990-95 C4 ZR-1 DOHC.

You will gain at least another 500 RPM peak power usable power band with an Edelbrock Performer Intake swap & a carburator correctly tuned on the primary & secondary side.
Part throttle & WOT.
Then you will notice a nice power increase from the seat of the pants & at dragstrip.

BR
 

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Best intake manifold ? I have a used performer I was gonna use because of hood clearance.
Id rather run an RPM.
http://forums.corvetteforum.com/c4-...6-what-carb-intake-will-clear-stock-hood.html

I hear they actually will RPM better and run through the midrange and up top stronger. .
Once the TPI is gone ,it is just another SBC limited only by the cam and heads
Wimpy stock cam (202/207 .404/.415 ) optimized for the TPI is probably going to run out of revs
before any intake you put on
A new cam better suited to the carb intake would make it kick a*se
 

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I am in the middle of doing this now.

This is what I have found....

performer rpm will not fit.
brodix hv1016 will not fit.
performer eps will fit with the perfect air cleaner combo.
performer 2101 will fit with standard drop base air cleaner 3" element.

on a stock motor I would run a performer 2101 and a 1850c 600 holley unless you can come up with a good Q-jet.

let me know if I can help
 

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My favorite Q- jet era to work with & build up is made from 1967 to 1974.

A Q- jet from a 1970 Corvette LT-1 & matching aluminum intake would be a nice addition to your 1987 Vette.

Same as the 1970-1/2 Z-28 Camaro had stock.

Would perform nicely on the street.

Q- jets can be tuned for WOT power & fuel economy on the street.
20+ MPG Average with highway gears & 700R4 overdrive, easy to do.

BR
 

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My favorite Q- jet era to work with & build up is made from 1967 to 1974.

A Q- jet from a 1970 Corvette LT-1 & matching aluminum intake would be a nice addition to your 1987 Vette.

Same as the 1970-1/2 Z-28 Camaro had stock.

Would perform nicely on the street.

Q- jets can be tuned for WOT power & fuel economy on the street.
20+ MPG Average with highway gears & 700R4 overdrive, easy to do.

BR


For sure :thumbsup:

Its hard to find good Q-jets these days though.
Q-jet have a certain life span and then after that they can be rebuilt, rebushed and all the crap but will never be the same.
I still love them though.

I have an old style Q-jet like you are talking about with divorced choke on an elcamino right now that gets every bit of 20mpg.

I also have a new 1850 600 holley on a Vortec 4.3 v6 in an s10.
I really like the Holley. I had to do a little tuning on it because it is really to big for the 4.3 but it would be a good out of the box carburetor for a stock or mildly modified 350.
 

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For sure :thumbsup:

Its hard to find good Q-jets these days though.
Q-jet have a certain life span and then after that they can be rebuilt, rebushed and all the crap but will never be the same.
I still love them though.

I have an old style Q-jet like you are talking about with divorced choke on an elcamino right now that gets every bit of 20mpg.

I also have a new 1850 600 holley on a Vortec 4.3 v6 in an s10.
I really like the Holley. I had to do a little tuning on it because it is really to big for the 4.3 but it would be a good out of the box carburetor for a stock or mildly modified 350.
Q- jets have Emulsion circuits, & Idle down tubes similar but different from a Holley.
You need a special extra long reach wire drill bit set & patience to fine tune them.....
Change or Remap the entire fuel curve similar to the removable air bleeds on a Race Holley HP 4150 series or Holley Dominator 4bbl.
Knowledge of how they exactly work & what each tiny drilled hole does.
When the last Q-jet was built around 1987, we still had 100% pure gasoline throughout the USA.
Today we have E10 87 octane for fast approaching $4 bucks a gallon again.

BR
 

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WEIAND X-CELarator intake fits under a stock corvette hood
 

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Its an 84 but the engine is a newer 96 block. The only thing the computer does is control the fuel pump.
 

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Do someone have any idea about the fuel economy on city and highway with carb?
Its actually very close, fuel mileage with a Carburetor Vs. EFI.
Have to tune a carb to get best results.
20+ MPG average on the street & highway is not out of the question on a 350 ci small block to 450 + ci big block.
 

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I know im gonna hear about it from the purists, but Ive messed around with this SD conversion mess someone else started. Ive got it running, its on the 3rd custom prom and it just keeps loading up. Runs hard when wide open, but still not right.
Nevertheless- Im not gonna waste this whole season messing around- I wanna drive it, so Im switching it over. I have everything to do it. I'll have it done in a day or so once I start. My question is for anyone who has done this.

How does yours run with the carb? I hear they actually will RPM better and run through the midrange and up top stronger.
Best intake manifold ? I have a used performer I was gonna use because of hood clearance. Id rather run an RPM. What have you experienced ? Thanks.
i am doing the same thing too lil 85 i have dumped a chunk into tpi not getting a pianless wiring harness im done got everything too carb it used part shopping less than 200 buck only thing brand new is gaskets and a pressure reg with return line and gauge eventually ill delete the ecm out completely with 8 to 12 pound pump ditch the fuel filter on frame hard line the missing gas can , and replace with filter at carb. top end is better anyway so light you will not even notice the 20 hp loss on low end but you can make up for it easily..and cheap
 
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