73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: jaime on January 08, 2014, 01:01:47 am
-
So I have an 87 silverado it has a 305 tbi an im not happy I want to put a new engine either a 350 carb or maybe go a little bigger and go with the 383 what do I need todo to get rid of the tbi stuff in the truck
-
wire cutters. but why you not happy? power? speed? take offs?
-
Kickdown for transmission, new distributor, throttle linkage, fuel pump or regulator. If you are starting with a new engine, biggest deal will be getting rid of all you unused wires.
I will be doing the same swap next year on mine. I don't understand why people don't like carburetors...
-
Why unhappy? TBI is actually simpler than carb and very dependable. i used to want to switch to carb, but if the car already has tbi, then i keep it now. My TBI cavalier has never broken down as far as the fuel system goes---original injectors and fuel pump as far as i know. Car is 23 yrs old.
Anyways if you want to switch, i think the first thing is you have to get rid of the in tank pump because that's definitely a restriction. You may able to use the same sending unit assembly with modifications or just get a non-tbi replacement unit that will drop right in. This is one of the advantages of doing this conversion on a vehicle that had both carbs and TBI in it's production run. All the fuel lines should plug right back up.
Well, actually you could leave the in tank pump in and use a regulator because the carb probably doesn't want 12-15lbs.
-
The 305 thats in the truck is actually a really good engine runs great I just want to beef it up a bit and ive been reading that its a waste of money to put in the tbi
-
Reallt I just want that loud choppy sound that I know the 305 probably cant produce
-
a waist to put a tbi in? then why are there conversion kits. now granted the benefit of a tbi isnt worth that of a Fuel injection engine but it is a step up from a carb. if you have one now and nothings wrong with it then i wouldnt change it just because. now if you find a 350 or whatever you want then yeah change it then. but keep the tbi for now
-
In that case a change of muffler and maybe cam can produce the loud choppy sound. A 305 can do it--mine did intentionally when cold.
-
I have an 87 that was converted to carb. It had a edelbrock 1406 but I have put on a SMI rebuilt quadrajet. It runs mint but I've been contemplating switching back to tbi. I'm getting 12 mpg combined with a th350 trans and a np205. I'm not sure of gearing but it originally had a 700r. Tbi is going to be more economical but likely less efficient. I'm still playing with it and I'm hoping for 14 mpg combined.
It is a fairly straight forward swap but make sure you get a fuel pressure regulator because your electric pump will put out way too much psi. You have to decide if it is worth it. You can easily switch back but remember if the carb is not set up well you are going to get poor fuel economy
-
Choppy idle means a big cam which means poor bottom end and good high rpm power and it is counter to good mileage. Unless you are building a race truck, skip chasing after a sound. There is much more to it than that. If you plan to daily drive this, you can get good power out of a 350 TBI without a choppy idle.
-
One of the most common complaints about the stock 305 is its lack of power. What are they, 170 hp or so? But they can be built to make a real good street machine, and you will have less $ output in a rebuild than buying another engine. Here's an article from Chevy Performance mag from a few yrs ago that you might find helpful.
http://www.superchevy.com/technical/engines_drivetrain/completebuilds_testing/sucp_1007_305_small_block_engine_build/
-
Note that the Ford 302 and Chevy 305 are just under 5 liters, and were built and highly modified for 5-liter racing classes.
You can get a ton of power out of a 305. All the hi-po parts are out there.