Quote: Originally Posted by Fast355 The power steering pressure switch is used with an anti-stall routine in the 8746 and the IAT is used for a little more timing advance in cooler weather. The truck 7747 has some advantages of its own. I would keep the 7747 for a while, then switch to the newer style PCM. This is one of the things that can be done with the PCM. http://www.youtube.com/watch?v=7nVQePIYzhI http://www.youtube.com/watch?v=c4CY3...elated&search= but can I just plug it into my computer harness and go? is that a video of you what is that in, a van thats pretty cool man...

No it is not a direct swap. You have to repin your harness to the newer connectors. All you have to do is remove the little pins from the connectors and put them into the corresponding new connector location.

That video is of my G20 Van. 350 TBI, 85MM GM MAF sensor, 1995 "427" PCM.

Here is a thread with alot more information on it.

http://www.thirdgen.org/techboard/tb...6197427-a.html (PCM Swap (16197427))

Newbie here.

I've only read some of the posts. My son and I just bought a 86 Z with TPI and 305/auto. The engine is knocking and is waiting to be buried with the bad gas in the tank.

We want to swap it for the 350. I used to own a 86 IROC. Man I wanted to put a big block in that car!

I read your post and have a few questions:

What 350 is best? Is one year, car or truck best, or what should be avoided?

What about a replacement 350 cam to go with the auto trans.? Crane PowerMax 2050?

Can you take all of the pollution sh&% off? Or should that go back on for the injection system or something?

I'm a little rusty. I used to build 396, 400 and 455s before I had kids. My sons got me back into it.

Thanks

Any 350 from 1973-1986 or so should be avoided if you are looking to use the stock heads, etc. The "best" engine to use would be a 1996-2002 Vortec 350. It has the great flowing "Vortec" heads, a Factory Roller camshaft, sometimes 4 bolt mains, Powdered Metal connecting rods that are stronger than the old "PINK" rods, Cast Aluminum pistons with a slight dish that give 9.4:1 compression with 64 cc chambers. Etc.

This is Biased toward a TBI buildup, but most of the same basic "Vortec" info carries across to the TPI. Just keep in mind with TPI you have to use a Vortec specific lower intake and a 350 specific knock sensor for your year TPI car.

http://www.thirdgen.org/techboard/tb...i-buildup.html (BUDGET TBI BUILDUP)

anybody live in the salt lake city area that will tune my 91RS 350 swap for cash. OR -->for all u others that wanna come to slc....im an airline employee offering a buddy pass round trip of course to slc....i just want my car tuned right! its hard to trust people that r just in it to make a buck or folks that provide a "quick fix."
this is for real....im not bullshi*ting!
i can't afford to blow my motor...the wife will flip!

airline service will b on delta/delta connection.......bring the eqiupment and u can be out the very next day...or even the same day!
email me

ok, I don't know if anyone else has asked this yet, but I'm looking into doing an engine swap very simaller to this one on my Blown up 92RS, will the intake bolt up to a pre vortec formerly carborated motor if not where can I get a motor that will work for this swap please let me see some links and prices.

You can make it bolt up by drilling the holes in the intake to fit the older block....but the best thing to do is just use an aftermarket intake for a carbbed engine..and use an adapter plate to convert it from carb to tbi.....That is if you have a tbi engine
What does it have in it

It's got a TBI 305, I would also like to know where I can find a motor that WILL actually bolt to the list of parts given in the 1st post.

1996-1999 OBS Chevy/GMC Truck, Suburban, Tahoe, Yukon.

1996-2002 Fullsize Chevy/GMC Van, Express, Savana

1996-2003 P-series vans

1996-2005 C60 Trucks

Hello Fella's,
Boy am I glad that I registered with Third Gen.org! I could really use some guidence as I am swapping my High Output 305 TBI for a 350 TBI with Twin Turbos.
I was just going to slightly modify and chrome up my 305, but upon removing the Intake Manifold, I noticed that my 305 had seen better days. So instead of rebuilding a 305, I bought a freshly rebuilt 350 L98 Short Block. I had already purchased an Edelbrock Performer Intake (for TBI, of course), a Holly 670 CFM Throttle body, Headers, all the chrome goodies and an off brand computer (performance) chip. Those were bought for my 305, but now I have this L98 350 and I still want to go TBI..
The 350 is mostly stock with Speed Pro Hypereutectic aluminum Pistons and the L98 roller cam. I just purchased 350 TBI Heads off of Ebay that I will put on the engine.

My questions are (and I am truley thankful for anyone's help):
1. will the ecm from my 305 work with the 350?
2. what will a performance enhancing chip do for that ecm?
3. what else should I change to accomodate the 350?
4. I bought a twin turbo for 82-92 small block Camaros. I didn't get any instructions with them. I was told that I needed forged pistons to accomodate the Turbo, but then I was told that the Speed Pro Hypereutectic Pistons would work fine. Which is true?

I am just a daddy that trying to give myself, my wife and my kids something to take to car shows, put around in, and if things work out O.K- maybe even take to the local race track. The turbo was a last minute decision that I went with just to do something unexpected (plus it was affordable). Can anyone help me out? All advice is greatly appreciated!

whoooh dude 1 at a time lol. well lets see what we got here
1. yes if its an 8746 ecm.
2.nothing unless you get into proming your own chips. Besides mail order chips just guess when you would be tuning based on facts. you might squeeze by with a chip out of a caprice.
3.although every1 says esc lol all part stores have the pn d140 for 305 and 350 lol prolly get shot for sayin that, injectors, knock sensor, and misc stuff
4. kool beans wish you luck on turbo

Thank You Colts45s,
When you get into the TBI's, it gets really confusing. I'm going to look into the turbo that I just bought off of ebay. It says its for 82-92 camaros with small blocks, but I wonder what kind of extra horsepower it will really put out. I need to find out if I need to change my Hypereutectic Pistons and possibly the hydraulic cam too. I greatly appreciate any advice!

The ESC modules ARE interchangeable between 305 and 350. One will work equally as well as the other.

When you start playing the numbers game, the late model Vortec 305 has the same knock sensor as a LT4 Corvette.

Hey Fellas, I (being a Mechanical Vigin) went and bought a Twin Turbo Kit for my L98 350 TBI. I also bought a New Nitrous Works Kit for TBI (it's complete with bottle full and everything else needed). Anyway, I learned that they do the same thing, basically, and now I want to try and straighten some things out. Is anyone interested in trading a Newly Rebuilt L98 350 Short Block with Aluminum Hypereutectic Pistons, Pacesetter Headers and Y- Pipe (their New), and a New Nitrous Works Kit for TBI- for an engine with Forged Pistons and the ability to handle the turbo that I bought?

I have Pictures if anyone is interested. I live in Warren, Ohio. Any advice is greatly appreciated also.

how many injectors do you need? isnt it 8

Wrong thread and forum guys, this needs to go in the "FOR SALE" forum.

Moderators please clean this up, this thread is getting difficult to read through.

Hello Gentlemen! My apologies, I'm very new to this forum and didn't realize there is a items for sale, forum. Again I apologize!
I made a mistake buying the twin turbo kit, because I found out that it's suited for engines that run between 425 and 525 horsepower.. Hey, my engine doesn't have anything near that, yet! I'm just going to build a 383 stroker with TBI and play around from there.. Any advise??

What if I get all the stuff, computer, throttle body, knock sensor etc from a blazer with a 350. Will that work?

Is there a diagram or picture that shows how all the vacuum lines are to be connected, namely the map sensor?

For the love of god guys, this is a mess!! This thread was ment to provide FACTS about swaping a 305 for a 350. It was not ment to ask questions in or discuss your project. I understand that some of you are new to the site and don't quite know how to find what you're looking for. The proper way to find information is to search, then if you can't find what you are looking for then post a NEW thread asking your question.

Sorry dude!I'll stop asking questions.lol

LMAO!!!!

hey could you please tell me where the esc is located on the 93 silverado.
because i also did the 350 305 swap. the esc on my truck isnt located by the throttle body like all of the other trucks i looked at. please comment back

Does not have one. The ESC circuitry is in the Memcal inside the PCM.

http://www.diy-efi.org/gmecm/compone...injectors.html

This says stock 305 TBI injectors are 40/lbs an hour... You say they're 55.

WHo is right?

could it just be any chevy caprice ecu box, and how do you tell if it is a 746' ecu, and do it have to be the police ecu box as well as injectors?also what if my car is not running lean and i've been driving it with the 350 for two months?

They are without a doubt 55 lb/hr. Regular old 350 injectors are 61 lbs/hr. Finally, even the 4.3 V6 has 46# injectors.

Got a quick question. I am doing a 350 swap in my 3rd gen z28. It is carbed what will have to be changed will I need to flash the ECM?
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Got a quick question. I am doing a 350 swap in my 3rd gen z28. It is carbed what will have to be changed will I need to flash the ECM?

What injectors/PCM would be needed for swapping in an old school 327? Currenly its running on the stock 305 setup, but not very well.

Now for that 350 chip . Could I just swap a Prom into my 305 ecm or would I just be better getting a 350 ecm all together ? I found that 350 prom threw autozone . But I am not sure . I am just trying to do it the easiest and fastest way . I got to race this weekend . HELP

what would the part number be for the caprice 350 tbi computer?

I'm new to this forum and thread. What great information you guys have here. I just picked up an 88 305 TBI Camaro with a siezed engine. I can't bring myself to put a 305 back in. Used 350's around here are going for alot of money. I have a contact at a GM dealership and I can get employee pricing. The question is, what would be a good crate 350 to start with? I don't have tuning skills yet. I want something I can either buy a prom for or get burned easily. I was thinking either the 87 and later stock replacement with roller cam or the 290hp from the performance parts catalog. Any comments? I need help!!!! Thanks.

Chad

I really need some help. I'm ready to get an engine. Thanks in advance for any comments.

I'm doin my swap right now...it goin good so far...

Guys, I promise I searched and didn't find much reference to crates except for the ZZ4. I don't have the skills to tune for that yet. I'd like to get a crate engine that a tune exists for to start. Little Help??

I dont know alot about the tuning end of it but all I did was buy a 350 out of a '93 truck and change the heads and cam....and of corse all the preventative maintenance stuff....
But you can pretty much buy any 350 and have a chip burned for it as long as you know the specs on the engine and what gear you have in the rear(if your going back tbi)if not then you need not worry about tuning..
I myself and a few of my friends have had great luck with Howell engine development( www.howellefi.com )...but theres also www.tbichips.com ..
they can burn you a chip to get you going with a few mods and they can walk you thru that...oh and if you end up needing a computer I have one you can get its a 7747 out of a truck if they say you need that....
also if you get a complete engine (intake to oil pan) dont change an intake out just get a 4bbl to tbi adapter plate like I have on mine in the pic above..
and you will need a tbi from a 5.7 litre truck or just buy a tbi for it from somewhere...
I'm sure I've missed alot and there is more to it than that but just keep searching on the net and you find what you need....anyone feel free to correct me if I've mislead....Dave

Thanks for the reply again Dave. I have the complete 88 305 in the car. It is in a bit of a siezed state at the moment. GM has this motor that I can get pretty cheap.

ENGLM1LS9

Part #
10067353

Engine Name: 350 LM1
Horsepower: 249 HP @ 5,000 RPM
Torque: 304 Ft/Lbs @ 3,500 RPM
Compression Ratio: 8.50 to 1
Block: 4 – Bolt, 2 Piece Rear Seal, 4.000” Bore
Crankshaft: Cast Nodular 3.480” Stroke
Heads: Cast Iron, 76cc
Valves: 1.940” / 1.500”
Camshaft lift: 0.390” / 0.410” Hydraulic
Duration @ 0.050”: 195° / 202°

The cam is not radical and it has decent power numbers at a reasonable 5000rpm. I am going to try to get a 746 ECM this week coming. I was hoping to just change my injectors, fuel pump, ESC module, and knock sensor. I was going to use the 305 intake and throttle body. I was hoping there might be an existing .bin that would run this engine. I am willing to buy the burner and chips. my goal was to get a .bin that would be drivable so that I could run the car and then learn the tuning part over time. Does this sound reasonable with this engine? GM also has part#12568758 which they list as an 86-95 L05 that is a few hundred dollars more than the one above. I just can't find details on it. Anyway that's where I'm at. Any comments would be great.

Thanks,

Chad

this is great. i just found a 350 tbi from an 87 caprice cop car with the ecm and harness. now all i have to do is follow this guide and i should be good.

Thanks in advance for your help!
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I would just like to add that mail order tunes are a wast of money in that you can not "build" a chip from a spec sheet. I don't care how good you are it just can't be done. The 747 has less features and even uses less sensors that the 746 It will swap in place of the 746 but there is NO reason to backdate.

If you are swapping in a stock motor and don't want to tune get a stock caprice chip. If you want to mod your motor learn to burn your own chips.

I think I have everything but the 350 ESC module, can someone explain what this is so I can try to find it.
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What is the ESC module?

Electronic Spark Control....

wouldnt it be eiser to go with a holly 750 double pumper and a msd 1 wire ignition dont need your computer that way

You're obviously lost, as this is the TBI board. We are interested in keeping the TBI and tuning it to a higher level of performance. So, to answer your question, yes it would be easier to swap to a holley, but we want the benefits that FI has to offer. So please take your "swap to holley" suggestion over to the carb board, it will be appreciated over there.

sry bout that i did have 30 or 40 tbi carbs 350 and 305 auto and clutch but i scrapped them for metal i thought e1 was swicthing

Like others, I'm in the midst of having my 91 RS converted from the 305 (A4)to a *gulp* 383 version from Five Star Engines in Phoenix. They will install the new engine along with a TBI from an 89 truck and new shorties from edelbrock. But what I read above is that I'll have to more than reprogram the chip, but get an entire new ECM. Since this will be an all inclusive engine swap, not just the short block, but all plumbing as well, beside the chip and ECM, will I need to have them replace the fuel pump as well? What about the ignition?

No need for a new ecm, you'll just need to reprogram the chip to fit your engine. See the "free tune" thread here in the stickies for a step by step guide to getting started burning your own chips.

I am almost done with my 305-350 swap... I went from a 305 tbi to a 350 tbi, the 350 came out of a 1994 4x4 chevy truck... I mean, I have my car on jackstands just getting it completely ready to drive, and it fires up first time every start, i can rev it just fine, but since its on the stands, i cant feel how powerful it is lol. Ill post some pics as soon as im done, i was just wanting to know how much more powerful its going to feel driving it. Will i notice a difference? I have just been so curious since the day i got this motor, which was almost a month ago... Thanks

im not sure where my esc is located in my 1992 rs camaro 25th anniversary editon. ive switched everything out but that module...anyone know where i can find it?

The modules are the EXACT same, no need to switch them.