i have an 89 305 tbi 5spd that I want to have converted to carb. I want the most power that i cant get out of this conversion but I dont really know what parts would be involved. If some one could please write me a list of specific parts that would great, everything that i would need to do this conversion while making the most power. I also wanted to add a new performance manifold and cam. Please any help would be great. I already read the sticky but pictures of this would be great, thanks!!!!!

Parts List:

- Carb
- Intake manifold
- Vac/Mech advance distributor
- Cam
- Fuel Pressure Regulator
- All necessary gaskets/bolts/fuel lines/fittings

Other notes:

- The fan will need to be re-wired to bypass the ecm
- Torque converter lockup will need to be addressed, usually manually controlled.
- Make sure carb had TV cable attachment on it if you are using the 700R4

Thanks!! any specifics on what brands/model to get?? also isn't the lockup only a problem in automatics, any pics of this conversion??

And heads. Don't forget TBI heads will thwart any other modifications done.

Carb: Avoid Edelbrock. Since you have a 5-speed, you'll want a double-pumper style carb. That means Holley or Demon, or a company that makes clones (Proform, Quick Fuel Technologies, etc.).

so i am going to need new heads??? why? and any particular heads you recomend?

fuel pressure regulator I used a mallory 4309 and it worked like a champ..will forward pics and 57kid is exactly right about the heads...they have a blockoff in the intake runner that looks like it takes away 30% of the flow. I picked up a set of tpi heads and they work much better with the new cam and intake. If you dont care about keeping the centerbolt valve covers there are a lot of good deals on 602 heads for like 150.00 a piece all over the web. The centerbolt tpi heads are a lot harder to find.Conversion went together very well but be prepared to spend some hours on stuff....Good luck

Buzzman1

here are the pics , I just got mine running

Buzzman1

601.

The '87-up heads have a different intake mount bolt pattern than 90% of carb intakes. Not a bad reason to give up center bolt heads.

Of course, there are also Vortec heads - center bolt valve covers, but requires a Vortec-specific intake manifold.

Thanks for all the input but im stil a little confused. This is my first motor bigger than 4cyl that i have ever touched. I am very unfamiliar with these 305's. What is the centerbolt head and a 601 or 602, and what would it mean if i i got heads that were not centerbolt?

you would have to get new valve covers but 57kid id right that the intake manifold bolt pattern is different on the centerbolt vs the older style heads. The intake cost me about $30.00 more for the newer style but there are a lot more choices for the older heads and they are a little less money. I stuck with the centerbolts because I had the valve covers and spark plug wire minders for the centerbolts.good luck

Buzzman1

416, 601, 081 - those are the last three digits of the head casting number.

Center bolt - Starting in 1987, the factory went to 4 bolts down the center of the valve cover to hold it on. Before that, they had 4 bolts on the perimeter of the cover. Hence, center bolt vs. perimeter covers.

dont let everyone scare you out of the heads you have

the throttle body heads make scary torque out of the hole which is good on the street

only drawback is that they dont flow well over 4500 rpms

so shift under 5k

i wonder if that why my time on the track was only 16.0-16.3 because i was shifting at 5k each shift

yeah if you want a quarter mile car these heads suck without major porting.

the exaust side flows really well but the ramp in the intake needs some major work

on the street it will pull really hard off the line to 5k

Why do you need a cam for a TBI to Carb swap?

To give it more power.

started to freak a bit.....

I thought the cam/dist. gear was different or something.

hey buzzman what throttle bracket did you use it looks like it worked quite nicely my stock one sits to far from the carb so it doesnt wrk

zig

it is a holley hly-20-95 and I had to move it back about 1/2 an inch with a piece of steel but that bracket lines it all up nicely..you will also need a a hly-20-121 0r something like that to line up the cables and if you are using the stock tv cable you will need to shorten the cable to get it in the right postion, I drilled a hole in a bolt and a nut to shorten the tv cable like a bike brake cable. If you need pics let me know and ill take them.good luck
Buzzman1

well i thought i was gunna need sumthin like that but my dad came up with an idea we actully cut the mounting holes off and moved them back about 3/4 of an inch and it worked great

thanx though
zig

hey guys i just bought an 88 firebird with no engine in it so im going to build a 350 to put in it so what im wondering is should i stay with the TBI set up or just put a carb on it ??? it has a 700R4 in it and im going to rebuild it for street/strip use. any help would be awsome ... thanx

i would go with a carb

Greetings from england. Im converting mine from tbi to carb and was going to use an edelbrock. However it seems after reading some posts that these are not suitable? Why not?

1990 camaro tbi going to carb with th350 trans have a 83 camaro carbed as donor for gas tank ans wiring harness getting rid of computer 83 has electronic fuel pump but was was origional carbed car does that sound right? any help would be nice

hey there,
what headers have you used?
im converting mine from tbi to carb and halfway from junking all the egr and seems a good time for a upgrade

im having the hedman shorty style put on mine right now they are pretty beastly you can get them from jegs for 159.00 plus shipping