305 TBI Header (?)s

[Moofus02]

I had an 88 scsb 2wd 5.7 tbi 700r4 and 2.73 gears. Motor jumped time and i swapped another 5.7 into it that came out of a 91 square body burb. That had a mild cam upgrade. It confused the computer some at idle but ran like a scalded dog once the rpm came up. I miss that truck lol. That said I've had tons of carbed 305 chevy cars and trucks. Most in full size wagons with 273 gears and 700r4 and one with a metric 200 3 speed. I love 305's. Screwed up a few years ago and didn't buy a stroker rotating assembly for a 305. Crank rods and pistons all new for$100. Didn't have a 305 but I'm still kicking myself in the ass for that. The crank, rods were worth the money. Scat parts and forged pistons. Should have bought it and hounded my buddies for a free 305 to put it into. A 334 I think would be

 

[98 Nitro]

I had an 88 scsb 2wd 5.7 tbi 700r4 and 2.73 gears. Motor jumped time and i swapped another 5.7 into it that came out of a 91 square body burb. That had a mild cam upgrade. It confused the computer some at idle but ran like a scalded dog once the rpm came up. I miss that truck lol. That said I've had tons of carbed 305 chevy cars and trucks. Most in full size wagons with 273 gears and 700r4 and one with a metric 200 3 speed. I love 305's. Screwed up a few years ago and didn't buy a stroker rotating assembly for a 305. Crank rods and pistons all new for$100. Didn't have a 305 but I'm still kicking myself in the ass for that. The crank, rods were worth the money. Scat parts and forged pistons. Should have bought it and hounded my buddies for a free 305 to put it into. A 334 I think would be

A relative of mine had two good 305 TPI engines I could have had dirt cheap a few years ago, i did not get them because you know 305s but i wish I had as @L31MaxExpress said good 350's disappearing fast, and 305s/334s can be good runners for daily driven trucks.

 

[jtdegreenia]

The simplest way to go is go to a treasure yard and grab an entire axle assembly that has 3.73 gears off a C series truck. ( the K series trucks have a track width that is slightly larger.) The yard in my area has axle assemblies for $95 and a $20 core.

If you take it off of 1500 it's a simple procedure. If you want to upgrade to a 2500 axle, you get more splines on the axle shaft and the 11 inch duo servo drum brakes instead of the 10 inch leading/trailing brakes that come in the 1500. You will need a conversion ujoint. That I do not have a part number for. Also the 2500 rear end comes with either six or eight lug flanges, you would either have to get wheels that would fit, or have the axle flanges plugged and re-drilled to fit the five lug wheels on your current truck.

(All this is moot if you already have 3.73 gears, but the brakes and sturdier axles would still be an upgrade)

The conversion u joint is moog 447

 

[Scooterwrench]

Long tube headers with 2-1/2" dual exhaust,1.94 heads and a decent street cam will liven up a 305. Basically the same engine as the 305HO of the mid 80's. No I won't be a 350 but it'll run pretty damn good.

 

[Jroctizzle]

Check out the Harris tuning website, soooo much good and thorough info on his site about building these engines.

Harristuning.com

As far as headers, going with the shorty is similar to the factory power range and long tubes give better top end power. I did mid length headers and a mild cam on mine and I like where the power sits, gets up and goes pretty quick, torquey and still good power through mid rpm.

That’s where you want to go through the Harris tuning website to figure out what you want out of it and have a look at his charts to ensure you’re looking at the right stuff!

 

[1989GMCSIERRA]

I wouldn’t spend the money. Seriously just get the truck running right, put stock cast iron manifolds and of the sun cabs it is rotted out mandrel bent 3 inch exhaust and free flow muffler. Get a TBI unit rebuild kit and check the gearing. If it’s a 3:08 got to a 3:73 ( I wouldn’t even do that ) maybe do some 275/60/15 when you need new tires and get the interior done and a paint job. If the truck has to be smogged you don’t really want to mess with it too much. And it doesn’t sound like you’re flush with cash so I would strongly suggest you don’t dump a ton of money needlessly in a old truck. I’m not trying to be a dik. I’m simply saying frrm a financial standpoint you’ll never recoup the money you put in that engine/truck. Go fix the car so it’s a decent daily driver and enjoy it as is.

If you had stacks of cash ok…but if you’re struggling the last thing you want is to dump money in a hole. Now if it needs parts a tune up brakes etc yeah that’s normal stuff. Now as stuff breaks yiu may want to update/upgrade that’s fine. You gotta swap it out anyway.
Yiu get the car running first and then as things wear you upgrade.

 

[89Sierra305]

I wouldn’t spend the money. Seriously just get the truck running right, put stock cast iron manifolds and of the sun cabs it is rotted out mandrel bent 3 inch exhaust and free flow muffler. Get a TBI unit rebuild kit and check the gearing. If it’s a 3:08 got to a 3:73 ( I wouldn’t even do that ) maybe do some 275/60/15 when you need new tires and get the interior done and a paint job. If the truck has to be smogged you don’t really want to mess with it too much. And it doesn’t sound like you’re flush with cash so I would strongly suggest you don’t dump a ton of money needlessly in a old truck. I’m not trying to be a dik. I’m simply saying frrm a financial standpoint you’ll never recoup the money you put in that engine/truck. Go fix the car so it’s a decent daily driver and enjoy it as is.

If you had stacks of cash ok…but if you’re struggling the last thing you want is to dump money in a hole. Now if it needs parts a tune up brakes etc yeah that’s normal stuff. Now as stuff breaks yiu may want to update/upgrade that’s fine. You gotta swap it out anyway.
Yiu get the car running first and then as things wear you upgrade.

This is probably the route I am going to take. But I also like to do things that people say not to waste time on. My last car was a 2005 Dodge Stratus with the dreaded 2.7L V6. I did some mods and it went from a slow little cruiser to something with a little pep and a sound system that rattled windows with no subs. Did I waste money? You better believe I did. Did I have fun doing it? Damn skippy. That's all I want to do. I may not be a mechanic but turning a wrench is as close to zen as I can get. I'm not building a drag and drive truck for Sick Week. I just want something I can say is MINE when asked. Whether someone is asking " Who drives that pos?" Or "Who's nice truck is that?" I look that person in the eye and claim it with pride. Thank you for your input it is appreciated. It shows you care about your own vehicle and enjoy owning it.

 

[89Sierra305]

Check out the Harris tuning website, soooo much good and thorough info on his site about building these engines.

Harristuning.com

As far as headers, going with the shorty is similar to the factory power range and long tubes give better top end power. I did mid length headers and a mild cam on mine and I like where the power sits, gets up and goes pretty quick, torquey and still good power through mid rpm.

That’s where you want to go through the Harris tuning website to figure out what you want out of it and have a look at his charts to ensure you’re looking at the right stuff!

Thanks for the info I'll look into it.

 

[L31MaxExpress]

I have a clean, standard bore roller 305 block that is destined to get a 3.875" stroke at some point in the future.

Check out the Harris tuning website, soooo much good and thorough info on his site about building these engines.

Harristuning.com

As far as headers, going with the shorty is similar to the factory power range and long tubes give better top end power. I did mid length headers and a mild cam on mine and I like where the power sits, gets up and goes pretty quick, torquey and still good power through mid rpm.

That’s where you want to go through the Harris tuning website to figure out what you want out of it and have a look at his charts to ensure you’re looking at the right stuff!

Long tubes are better for low-end torque. Tri-Ys even more so. Short tubes are better than manifolds, but tri-ys or long tubes make more power everywhere.

 

[Sean Buick 76]

I have a clean, standard bore roller 305 block that is destined to get a 3.875" stroke at some point in the future.


Long tubes are better for low-end torque. Tri-Ys even more so. Short tubes are better than manifolds, but tri-ys or long tubes make more power everywhere.

Tri Y with turbos is the best for torque lol