Completed the 305 TBI to 350 Vortec swap on my Son's 1990 RS Camaro this week. We bought a 4 bolt main Vortec 350 off Craigslist with 50K miles on it for $150. Parts used for conversion: * Vortec 4B high rise intake * 4B to TBI adapter * 350 ESC module - GM 16128261 * 350 knock sensor - GM 10456288 * 8746 ecm & injectors from 89 Caprice Cop car * Headers (right factory exhaust manifold will not work on a Vortec head) * Flywheel 168T(flexplate) for 350 Vortec * Starter for 168T flywheel. * 1.6 Roller rockers (best upgrade to a 350 Vortec)

Welcome aboard thirdgen.org.

Looks a lot like the Budget 350 TBI swap. Good work.

When are you going to get that header paint burnt off???

Nice 57 you got there. I had a 57 Belair 2D HT in high school running 4.88 gears & a six pack. Awe the memories.....

Didn't take long for the header paint to get broke in.

My son & I also rebuilt the 700R4, upgrades include, 2,200 stall convertor, shift kit, Corvette servo, Beast sunshell, 5 gear planets, .500 boost valve, wide Kevlar band, and HD red clutch packs.

Nice job man! How much did the whole swap cost you all together? How many hours did you guys put into the swap? I wanna do this with my 305 but dunno where to start!

enraged, welcome aboard thirdgen.org.

This is a bit of a thread highjack, but which induction do you have, carb or TPI? I'm assuming from your username you have an '85. Carb, it's simple, just get a Vortec q-jet intake manifold and put your carb stuff on the Vortec longblock. TPI is a little trickier, but a Vortec TPI base is available (the results just aren't as good without more (and expensive) TPI hardware).

Heslekrants, sounds like it was a great father/son project. If you have more pictures/details as you went along, would be great to hear.

We bought part from Craigslist, Ebay and NAPA.

Parts used for conversion:
$150 * 4 bolt main Vortec 350 with 50K miles
$100 * Valve job on heads from the 350 long block
$100 * Vortec 4B high rise intake
$ 30 * 4B to TBI adapter
$ 2 * 350 ESC module - GM 16128261
$ 2 * 350 knock sensor - GM 10456288
$ 60 * 8746 ecm & injectors from 89 Caprice Cop car
$150 * Headers (right factory exhaust manifold will not work on a Vortec head)
$ 5 * Flywheel 168T(flexplate) for 350 Vortec
$ 20 * Starter for 168T flywheel.
$ 90 * 1.6 Roller rockers (best upgrade to a 350 Vortec)
$ 90 * Chrome polished timing chain cover & chrome valve covers
$ 26 * Throttle body rebuild kit
$150 * Gaskets, misc items
-100 * Sold the 305
$875 * Total

Since we decided to beef up the tranny ourself this project took longer than it should but well worth it in the end. My 3 boys each have project cars so my time is sprend pretty thin plus I have my own project.


This is what the bottom end looked like when we bought it.


Just rebuilt the front suspension and lowered the front by 1.5", this is a before pic.

Man I can easily put $1000 together and buy all the stuff but my issue is, I have no idea what I am doing lol. What would kill me is the labor if I don't have anyone that could help me put it in myself.

It passed emission testing 1st time thru today with the 350 Vortec installed.

Where I live they test 1975 & newer cars.

Heslekrants, where'd you get the gauge face deal?

That looks like a nice little upgrade. I have a similar setup in my car. I also went from a 305 to a 350 TBI Vortec motor. Good Stuff

How does she work?

I did a TPI/Vortec 355 in an 85 IROC, and it worked much better than stock. Dropped.1-1.3 seconds in the 1/4 mile and 11-12 mph with ZERO ECM tuning.

Nice work Heslekrants. I would do as you did with using the Vortec carb intake over the TBI/Vortec conversion intake manifolds.

what are you basing your roller rocker comments on? Just curious if you have used them on previous projects? Any before after roller rocker impressions?

peace
Hog

My gauges came out of a 92 Anniversary Addition Camaro.

The Vortec motor makes this Camaro scream. I can break the tires loose at 40mph. Those 245/50/16 rear tires just can't handle the extra power. Plan on taking it to the track next year. It feels faster that my 08 Grand Prix GXP that runs 13.8 in the 1/4.

I installed the 1.6 roller rockers on my 5.7L 99 Suburban at 150K miles and it gave the motor a new life. It stopped down shifting on this one hill I have to pass to get to work because of the extra power. It was still a powerhouse when I pulled the motor at 225K miles to install an aluminum headed int balanced 6" rod 383 stroker motor.

What times were you getting in the 1/4 mile? What rear tires were you using?

Last time out with no ECM tuning netted a 13.8 at 99 mph 1.8-1.9 60ft on 3.42 gears. Thus was on 245/50/16 Defenders on the stock 16x8" rims
Stock with the 305 ran anywhere from 15.3-15.88 86-89mph.

4bolt 355 L31 with LT4 Hotcam kit.

Thanks for the info on the 1.6 roller rockers.
I have a 97 Vortec 350 reg cab shorty with the Mercruiser Marine intake with 24# EV6 injectors. With the old combo the bests were 14.8@94mph with a 2.007 60ft. Hopiing for mid 14's this year in the truck.

peace
Hog

I have 4 cars to take to the track in Spring.
* 90 Camaro 350 Vortec TBI -I'm hoping for 13.9. (youngest Son's car)
* 08 Grand Prix GXP -I just bought it, shooting for 13.8
* 99 Suburban 383 stroker 6" rods, int balanced, alum heads, .534 lift
* 74 Camaro 454 pushing 550hp, too many mods to list. (oldest Son's car)

I just totaled an 04 Grand Prix that ran 14.7 stock and my wife's 06 V6 Mustang runs 14.7 with major traction issues (4.10 posi rear).

Nice herd you got there. I hope you acheive all your goals.

peace
Hog

I've got a 305 tbi in my firebird what all would i need if i put a vortec 350 in there. (as cheap as possible.)

Sourses for parts are Craigslist, Ebay & junkyard.

Parts used for conversion:
* Vortec 4B high rise intake
* 4B to TBI adapter
* 350 ESC module - GM 16128261
* 350 knock sensor - GM 10456288
* 8746 ecm & injectors from 89 to 90 Caprice (Cop car if you can find one)
* Headers (right factory exhaust manifold will not work on a Vortec head)
* Flywheel for 168T(flexplate) for 350 Vortec
* Starter for 168T flywheel.
* 1.6 Roller rockers (best upgrade to a 350 Vortec but not need for the conversion)

If you stick with a 350 TBI motor you won't have to change the intake & exhaust then it's a really cheap ungrade. The Vortec 350 is a much better motor though. For me & my son it was worth the extra $$ & hassle.

Good luck with your project & let me know how it goes.

Forgive my ignorance, I'm new to the GM engine world. What exactly is the Vortec block, versus the 86-up and the 85-under? I don't get the differences.

I can tell the difference between an FE and Cleveland blocks (old Ford guy). But I need a little GMucation. Please elaborate.



Thanks
CamaroCop

I guess I should elaborate myself.... I am looking to replace my 305 with a 350 and I don't really know where to begin, there's a lot of stuff out there for them and I am a little confused.

I want approximately 350 horsepower, don't want to have to change my transmission (5 spd) or rear end out. I want to go from fuel injection (hate in car computers more than I hate a juvenile delinquent) to carb. I want something smooth, reliable and comfortable for daily driving and long cross country cruises with my wife.

Would the Vortec block be the way to go? If so, where could I get information about them so I can start collecting rebuilding parts?

Dont they make an TBI Vortec on the older trucks?

Vortecs came out in 96, I've never heard of a TBI Vortec.

I know that the 4.3's have TBI. And they had V6 Vortec's in the 80's.
I guess i just figured that if they were on the 4.3 they would be on some V8's

Yes you are correct, the 4.3 V6 Vortec first appeared in 1986 but the Gen 1 V8 Vortec came out in 1996.

There was a TBI Vortec in 1996 only:
TBI L31 applications

• 1996 G-Series vans over 8,500 GVW w/ 4L80E transmission

If the 4.3 is the same block as a 5.7 would the intakes interchange?

SBC(Gen 1 only) basics
55-86 - intakes can interchange
87-95 - intakes can interchange
96-2003 - L31 only, intakes can interchange

You can swap heads between the different blocks but the correct intake must be used, roller cams & 1 piece rear mains started in the late 80s.

A Vortec block uses a plastic timing chain cover & only 8 bolts on the intake. The 350 Vortec block # is 880. I 305 Vortec block # is 878.

Here some Chevy V8 block info
http://www.mortec.com/castnum.htm

The 4.3(V6) is basical a 5.7(V8) with 2 cylinders cut off so some part will interchange but not the block, heads, intake.

Now that I think about I have no idea why I thought that would fit?

why didn't you just the stock 305 flywheel/starter?i'm getting ready to do this swap for a friend using a 5.7 vortec with the gmpp tbi intake.also what brand headers did you use and was there any y-pipe mods needed for the headers?

The 5.7 Vortec uses a neutral balance damper but has a weight on the flywheel so you have to change the flywheel. The stock flexplate is a 153T but the Vortec has a 168T so the starter had to be replaced as well. $20 at the yard.

The headers are Summitracing brand and come with the y pipe & emission stuff. We have emission testing where I live and it passed 1st time no issues.

The '86-up one-piece RMS 305's have exactly the same weight. You can use the 305 parts on the Vortec 350.

thanks,were trying to reuse as much of the 305 accessories as we can.i hadn't counted on the header problem but we'll do it if necessary.

I saw your post on the swap and it looks good. I am planning on the same or similar swap. I have an 89 Camaro w/ 305 TBI 5spd. I looked on Summit's website for parts you spoke of (i.e. headers with A.I.R. tubes, 4BBL to TBI adapter, and appropriate intake) but didn't find anything suitable. Other than what is in previous posts, what are the part numbers and where did you purchase them? What was the problem with the exhaust manifold that it didn't bolt to the head? Did you use the EGR? If not does it set a code? I live in an emissions area also and that is a concern. Sorry for the lengthy question, but any info would be appreciated. I just joined this MB and hope I did this correctly. THANKS!!

Headers with y pipe - Edelbrock #350-68723 Jegs.com
TBI adapter - Trans Dapt 2210 Jegs.com
For hood clearance I went with NEW SBC CHEVY Vortec Dual Plane Aluminum Intake 305 350 new from Ebay. An air gap intake would be nicer but you may need a hood scoop.

On Ebay now is a GM 12486572 Vortec Intake Manifold designed for the TBI and has provisons for EGR. You don't need the TBI adapter using this manifold.

I have emission test too and passed 1st time without the EGR installed.

The factory 305 starter & flexplate do work on the 350 Vortec. We had a small vibration running the 305 flexplate on the Vortec 350 only to find out the new torque converter was out of balance.
I went with the 4 barrel intake for more options down the road.

The factory 350 Vortec heads don't have the outer exhaust bolt hole that is needed
for the factory exhaust manifold.

An Air Gap and non-Air Gap version of the same type of manifold (both Performer, or both Performer RPM), are exactly the same height.

The air gap is produced by dropping the "floor" into the lifter valley.

True, but you can't get an air gap Performer intake so you would have to go with the Performer RPM to get the air gap which is taller. With the tight hood clearance of these 3rd gen Camaros & running a TBI adapter plate you may run into a tight fit.

Measure twice install once.

Thanks to you both for the speedy reply. I have been looking at my different options and will probably use the GM 12496821 route due to the underhood inspection along with the dyno test for emissions. I am going to make sure the car is lined out and safe before making the modifications.

Marine engines and Mexican trucks.

Do you know what years? The only thing I could find was 1996 G-Series vans over 8,500 GVW w/ 4L80E transmission had a TBI Vortec motor.

Sounds like a needle in the ole haystack to me.

The Mexican trucks were made from like 96-98 and did not use EGR. You can tell this one has Vortec era accessories on it because it is a 1998 Grand Blazer with a TBI.



Grand Blazer is a redressed Tahoe.



The marine engines are fairly common and came with a 2" bore TBI. Notice its even stamped with the OEM engine, Crusader.

Understand what you mean now.

Performer Air Gap is available, but not in Vortec style.

I know this is kind of an old thread but I am kind of confused about something, you said you bought a high rise 4B intake but you provided a link of the one you used from eBay and it isn't a high rise is it? If someone was to need the EGR valve on their engine which intake will fit under the stock hood and have the EGR capabilities?

I have the same situation. The only ones I found EGR capable are from GM. They show up on ebay at times. JEGS and Summit sell GM intakes also. I just bought the Vortec TBI intake off of ebay. It was offered with the pipe for the EGR ($85.00 from GM). The Vortec intakes need the pipe adapted into the exhaust to supply exhaust gassas for the EGR. These intakes can be pricey even on ebay. The latese price for the TBI Vortec intake is $363.00 plus the other pieces GM recommends for EGR functionality. GOOD LUCK!!

The intake is taller than stock but not as tall as a full high rise. The link should be the intake my son is using.

If you have to have your EGR then go with the GM TBI intake. I passed emissions (tailpipe test) without the EGR hooked up.

so alot of you guys are saying 1.6 roller rockers are best for vortec but what valve covers do i need? I bought some from autozone and they dont fit in between each rocker there isnt enough space.

I am going to use Comp Cams Magnum roller tip rockers, they will fit under the stock valve covers without any modifications. Some others have modified their valve covers to work with some other brands of roller rockers but since I have never seen a set modified I am not sure how they are doing it. I have read the narrow body rockers will fit under stock valve covers if you want full rollers

well theyre not very narrow there is a very small gap between them.

so if you don't use the vortec stock injection and use the tbi you don't have to wire in the crank shaft sensor and just get the right injectors and computer correct?

Hello,
So I read your post on 3rd gen and was hoping you can shed some light on my swap? I just this last week have swapped out my stock 305 TBI 91 RS camaro with a 96 350 Vortec long block. I then attached everything off the 305 to the new engine.. I ordered a conversion plate from ebay that will allow me to use my edelbrock manifold with my original TBI... So my question is... since I am still waiting for the part to arrive from Ebay before I can start the car... what problems will I run into? From what I read on your post you change flex plate? injectors? am I about to run into a problem? I used all the original hardware.. I deleted the smog crap too.. any info you could provide would be great...
Thanks Mike

The stock 153 tooth flywheel & starter from a 90-95 305 will work as they are weighted just like the 350 Vortecs are. I don't know about pre 1990 305s.

These are cheap from a junk yard & will make the 350 run better.
* 350 ESC module - GM 16128261
* 350 knock sensor - GM 10456288

You will have to run headers (right factory exhaust manifold will not work on a Vortec head because its missing the left outer bolt hole on the exhaust.. or at least mine was)

It is best to get a custom chip made for your setup to run its best but it will run with the stock 305 setup.

For best performance you should install 350 injectors & increase your fuel pressure from the stock 14ish to 17-18psi with an adjustable regulator.

Optional
* 1.6 Roller rockers (best upgrade to a 350 Vortec) If you go with the roller tip rockers they should fit under the factory valve covers.