How to: 305 To 350 swap....everything you need to know - Page 5 - Third Generation F-Body Message Boards

Go Back  Third Generation F-Body Message Boards > Tech Boards > TBI
Reload this Page >

How to: 305 To 350 swap....everything you need to know

TBI Throttle Body Injection discussion and questions. L03/CFI tech and other performance enhancements.

How to: 305 To 350 swap....everything you need to know

Old 12-01-2009, 05:44 PM
  #201  
Member
iTrader: (2)
 
Join Date: Nov 2009
Location: Hubert, NC
Posts: 436
Car: 83 Z28
Engine: F-body LT1 swap
Transmission: T-56 swap
Axle/Gears: 10 bolt w/ 28 spl posi, 4.10, disks
Re: How to: 305 To 350 swap....everything you need to know

Wow, I just spent the last hour of my life reading this hoping for clairity, but I did not find it. So I am about to interperet this and spit it back out and hope I am not too far off base.

-Background on me is I have an 83 Z28 with Cross-fire injection. A 350 was stabbed into it at one time before I took posession of it. I frequent the Cross-fire injection forum and try and speak vette the best I can.

-According to the vette guys, and the chart for knock sensors above, GM used the same knock sensor for all cars up till 86. (makes sense, they changed the motors around in 87)
a. Would it make a hoot if I used a later model knock sensor?
b. What real difference am I going to notice?

-I also know that my ECM and a 84 Vette ECM are the same. I only need to change my PROM and injectors. (done the injectors, but not the PROM)
a. I can get a custom PROM burned for an 84 Vette with better maps on it, should I do this and deal with a general tune or pony up and try and learn to burn chips?

-I am also pretty sure GM used the same electronic spark modules for the HEI style distributors.

-This in turn would mean that most swapping issues will be relegated to the 87 and later 305 to 350 swaps.

-Because with just 350 injectors, newly bushed TB's, and TB balancing, my camaro really scoots and melts tires at will. (even catches a 2nd with no shift kit)
supr_fly03 is offline  
Old 01-02-2010, 04:40 PM
  #202  
Junior Member
 
Join Date: Jan 2010
Posts: 1
How to: 305 To 350 swap....

ok so i got a 1991 camaro rs 5.0 305. ima be geting a suburban with a 350 in it i believe its a 1990 model. and i wanted to swap my 305 to the suburbans 350. what do i need to do in order for this to happend. and what parts do i need?? please help THANK YOU!!!
CHEVY1991 is offline  
Old 02-09-2010, 01:22 PM
  #203  
Member
 
Join Date: Jan 2010
Location: four oaks, nc
Posts: 226
Car: 89 rs black
Engine: 305 v8 tbi
Transmission: 700r4 stock
Re: How to: 305 To 350 swap....everything you need to know

hey I have a very serious ?
Now I have a thread in the general section about all my adventures with this rs I just bought and yesterday I pulled the #1 plug to find it covered in carbon which might explain why it won't crank it's raining today I can't check the rest of them. but the guy that I bought it from said it was a 350v8. well the 89 rs only came with a 305 but I've seen pics of 350 tbi that look exactly like mine how can I tell the diff between them and know for sure? I had my wife pick up some plugs and now I don't know if they are the right ones. ohhhhh I did check the firing order and timing car had been sitting for a while.
rs owner is offline  
Old 02-25-2010, 01:11 PM
  #204  
Junior Member
 
dippin88's Avatar
 
Join Date: Jun 2009
Location: Orange County, CA
Posts: 94
Car: 1988 Camaro sports coupe
Engine: LS1
Transmission: T56
Axle/Gears: 3.42
Re: How to: 305 To 350 swap....everything you need to know

hello i did a tpi swap into my tbi where can i find a tbi bulkhead connector diagram any1 know i need your guys help?
dippin88 is offline  
Old 02-26-2010, 12:47 PM
  #205  
Junior Member
 
pandemic_ratio's Avatar
 
Join Date: Aug 2006
Location: Port st lucie Florida
Posts: 55
Car: 1992 RS Camaro
Engine: 350 small block V8
Transmission: icky automatic
Re: How to: 305 To 350 swap....everything you need to know

you can try a Haynes manual. i think they have it in there.
pandemic_ratio is offline  
Old 03-08-2010, 06:20 PM
  #206  
Senior Member
 
Join Date: Sep 2009
Location: who knows
Posts: 614
Car: '90 Camaro
Engine: 305 tbi
Transmission: T5
Axle/Gears: 9 bolt posi 373
Re: How to: 305 To 350 swap....everything you need to know

where would i find a 350 ESC module new or used
DiabolicalRS is offline  
Old 03-08-2010, 08:27 PM
  #207  
Senior Member
iTrader: (10)
 
dctrumpet's Avatar
 
Join Date: Feb 2006
Location: Central Illinois
Posts: 736
Car: 1992 Firebird
Engine: 350 TBI W/all Ultimate TBI Mods
Transmission: 700R4
Axle/Gears: 9 Bolt 3.27
Re: How to: 305 To 350 swap....everything you need to know

PM Sent to you!
dctrumpet is offline  
Old 03-12-2010, 05:33 PM
  #208  
Junior Member
 
steven hecker's Avatar
 
Join Date: Sep 2009
Posts: 16
Car: 1992 GTA
Engine: 305 TPI
Transmission: 700R4
Re: How to: 305 To 350 swap....everything you need to know

i currently have a 305 tbi in my 92 firebird i plan on installing a 350 hp chevy 350. i was wondering if it would be best to use a chip and injectors from a 454 or a 350 tbi engine or are their any mail order chips i could get that would support 350 hp. i dont know how or want to burn my own chips.
steven hecker is offline  
Old 04-03-2010, 11:44 PM
  #209  
Junior Member
 
Join Date: Apr 2010
Posts: 2
Car: 87 Trans am
Engine: 350
Transmission: 700R4
Axle/Gears: 3.73
Re: How to: 305 To 350 swap....everything you need to know

I just did a 305 carb to a rebuilt 350 in an 87 trans am, kept the electronic carb/ dist starts up with pumping gas pedal down, sputters, keep at 2k rpm smooths out nice, let go of pedal coughs turns off. Also put in gear coughs then dies, I increased the idle stays running now, put in gear, cough, dies. Some mentioned timing? too advanced?/other? professional rebiuld so engine is good. Anyone?
ebaywin2k9 is offline  
Old 04-04-2010, 01:51 AM
  #210  
Supreme Member
iTrader: (4)
 
Ozz1967's Avatar
 
Join Date: Dec 2005
Location: St. Cloud, MN
Posts: 4,729
Car: 1984 Trans Am
Engine: In progress 6.0 LS swap
Transmission: 4l60e with 3600 FTI converter
Axle/Gears: Zexel Torsen 3.73, 28-spline mosers
Re: How to: 305 To 350 swap....everything you need to know

Originally Posted by ebaywin2k9 View Post
I just did a 305 carb to a rebuilt 350 in an 87 trans am, kept the electronic carb/ dist starts up with pumping gas pedal down, sputters, keep at 2k rpm smooths out nice, let go of pedal coughs turns off. Also put in gear coughs then dies, I increased the idle stays running now, put in gear, cough, dies. Some mentioned timing? too advanced?/other? professional rebiuld so engine is good. Anyone?
What size cam are you running now? Did you put your original 305 back on the new motor? I have the same problem on mine and it took calling a guy who "WROTE" a book on Qjets to finally understand what happened (we'll find out for sure when I get my carb back from the shop later this month).

Check your vacuum at idle. What we believe happened to mine, after installing a new 350 with a much bigger cam than stock, is that I'm not pulling enough vacuum at idle to get fuel through the idle circuit. Sure, you can turn up the idle screw which raises the RPMs and takes the carb OFF of the idle circuit...allowing fuel to pull through the main circuit. Then, you drop it into gear which drops the RPMs back down into the idle circuit range, starving the engine and stalling it out. Now, the only reason we came to this conclusion is because I went from 22hg of vacuum at idle with a stock cam profile to 9 at idle with the new cam, something my carb, built for a 305 just can't handle. So, check your vacuum at idle, if it's lower than say, 16, this could very well be your issue. Like I said, it's only theory right now, but I will find out more once I get my carb back from the shop with it's idle circuits modified to handle the lower vaccum. Hope this helps!
Ozz1967 is offline  
Old 04-04-2010, 11:29 AM
  #211  
Junior Member
 
Join Date: Apr 2010
Posts: 2
Car: 87 Trans am
Engine: 350
Transmission: 700R4
Axle/Gears: 3.73
Re: How to: 305 To 350 swap....everything you need to know

Yes the new cam is a nice lumpier one, from stock. I got it to idle better at lower RPM by adjusting the timing, counter clockwise, the carb when it was in the 305, did have slight problem when the engine warmed up, rpm drop to around 5k-6k an then moved up to around 7k range, when I put it in gear, so I guess not the best carb and probably I should rebuild? thanks!
ebaywin2k9 is offline  
Old 04-11-2010, 06:56 PM
  #212  
Junior Member
 
Fastcar92's Avatar
 
Join Date: Jun 2005
Location: Hemet, Ca.
Posts: 41
Car: 91 RS Camaro
Engine: 350
Transmission: 5 Speed
Axle/Gears: 3:08
Re: How to: 305 To 350 swap....everything you need to know

Originally Posted by BMmonteSS View Post
Ok, my head just exploded from the bajillion’th 305 to 350 swap question. So I’m going to compile some info here and just post a link from now on. You more experienced guys feel free to add or correct me where I’m wrong.

The age old 305 to 350 swap is probably one of the most popular swaps. Here is a list of items you need to make the swap, followed by an explanation of why you need them.

YOU NEED:

350 injectors
350 specific knock sensor
350 ESC module
350 chip

WHAT WILL WORK ON BOTH ENGINES:
Intake
Throttle body (the truck TB’s might have different throttle cable hookups, but otherwise are identical to the car variants)
Injector pod (although it’s easier to swap the whole 305 pod for the 350 pod)
Exhaust
Distributor
Accessories
ECM (as long as it’s a 746’)
Flex plate
Starter

WHY YOU NEED WHAT YOU NEED:

INJECTORS: Stock 305 injectors are 55 lb/hr, stock 350 injectors are 61 lb/hr, if you use 305 injectors with a 350 ecm the computer will think it has the stock 350 injectors and run lean. Get these from a junk yard or check e-bay.

KNOCK SENSOR: The knock sensors are different because they are tuned for the bore size of each motor. Get this from the junk yard or any parts store (I suggest new because they’re easy to damage taking them out).

ESC MODULE: Tuned for knock sensor and engine. Get this from a junk yard, e-bay, or any parts store. In a pinch you can get by with the 305 module, but I don’t suggest it.

CHIP: This is the most important part, the ECM is a speed density system which means it relies heavily on calculations to inject the proper amount of fuel. One of the bases of those calculations is the cylinder size and injector size. If you use a 305 computer and injectors on a 350 it is going to run LEAN because the ecm thinks there are 50 less cubic inches than there really are. If you just throw 350 injectors on there it will throw the whole tune back to the rich side because you will then have injectors that are much bigger than the ECM thinks it’s controlling. It won’t balance out with a 305 ecm and 350 injectors.

WHERE TO GET YOUR CHIP: The 746’ ecm was used in F-Bodies and Caprices, you could only get a 350 with TBI in the caprice. So you need to get your chip for a caprice, the “cop car” chip is popular because it has the speed limiter deleted and is set up for the larger cop car 65 lb/hr injectors, you’ll just have to source the cop car injectors (try eBay). A lot of people here get their chips from TBI chips or some other mail order company. I’m personally against giving these people money, but they cost about the same as a stock chip from GM ($80-120$) and you get some basic things done like the speed limiter delete, more timing, and unfortunately more fuel at WOT (you actually need much less). If you are going to be doing any major modifications to your 350 at the time of install or in the future, you may want to consider getting the chip burning equipment. It cost in the neighborhood of $120-$150 and you’ll be good to go for any modifications in the future. I’ll supply you with a 350 bin file (I’ll even make some “performance modifications”), or you can download them from one of the many sites that have them (Moates.net, tunerpro, ect.)

A word about the stock fuel pump, the stock camaro fuel pump is almost inadequate from the factory. So there is a good possibility that your 100,000 mile stocker might not be able to keep up with the added fuel demand of the 350 at high rpm’s. If you replace it go with a TPI pump or a walbro 190, your regulator will cycle the extra fuel volume back to the tank. Remember the regulator determines your pressure, the pump simply provides the volume.

Anything I missed? Anything need expanded on?
Is the ECM the silver box where the chip goes? I have a 91 RS Camaro with a 350 bored 30 over and a cam and chip,I need the knock sensor and the ECM so what year of what type of car do I need. 3in. catbacks, 1in. TBI spacer,5 speed
Fastcar92 is offline  
Old 05-10-2010, 06:33 PM
  #213  
Member
 
Join Date: Dec 2008
Location: stedman
Posts: 178
Car: 1992 25th anniversary RS Camaro
Engine: 305 T.B.I.
Transmission: ????
Axle/Gears: ??????
Re: How to: 305 To 350 swap....everything you need to know

would it work to put a 350 chip into the 305 esc module.
bigred75 is offline  
Old 05-25-2010, 10:47 AM
  #214  
Junior Member
 
Join Date: May 2010
Location: australia
Posts: 1
Re: How to: 305 To 350 swap....everything you need to know

does the conversion of a 305 to 350 require upgrading the cooling system. i have a 85 trans am that over heats whenever the weather is above 20celsious/ 68 farenheight, could it be something else, the water pump,injectors and thermostat were all replaced with new 290hp 350 engine. i only have to drive 20km / 32 miles in distance b4 it gets to 220+ on the gauge and thats on a cold day. btw it already has a thermo fan.
thanx aussie trans am

Last edited by reeves; 05-25-2010 at 10:48 AM. Reason: spelling error
reeves is offline  
Old 09-22-2010, 08:49 PM
  #215  
Junior Member
 
Join Date: Jul 2009
Posts: 2
Re: How to: 305 To 350 swap....everything you need to know

oh okay my name is jonathan hiatt me and my dad have a 1989 firebird with a t-5 brog wanger trans bolted 305 tbi. we have a napa 80 gals per hour at 26 psi fuel pump cold air intake about 18 psi on the injectors 5.0 rs camaro injectors. with a 1 in truck 305 tbi spacer and we can run all day at 65 mph at less then 1500 rpms on the tach and it has 3 degrees of spark adavnce and i never disconnected the wire to recab the ecm for the adavncement in spark tuning. and that at 95 mph we are doing about 2200 rpms and it is all factory from intake manfoild down and the cat is factory and we have passed emsions with it and it had very low emsions and that we only have a magaflow muffler and that we can **** 1st 3rd to 5th or 5th to 2nd or 1st to 5th with out boggin the motor down. and have gone sideways in the bird for about a 1/4 mile with no problem and that ist has well over 178XXX miles on it and still running strong and i can get past the stock rev limiter of 4300 i can start in firts gear and take off and go all the way up to 5000 rpms and keep it there with no problems and i have also gotten the bird up to 5500 rpms a few times and it stills runs good on the air fuel mixture so yea if you have any questions just mail me at [email protected] and oh yea we are using stock ecm and eprom and can i sue what i have on the 305 for the 350 engine

Last edited by pfchiatt; 09-22-2010 at 09:05 PM. Reason: forgotsome things on it
pfchiatt is offline  
Old 09-27-2010, 03:43 PM
  #216  
Supreme Member
iTrader: (6)
 
SiCkRs's Avatar
 
Join Date: Dec 2008
Location: Norwalk, CA
Posts: 2,535
Car: 91Z28
Engine: 5.7 ls1
Transmission: 4l60e
Axle/Gears: 3.42
Re: How to: 305 To 350 swap....everything you need to know

Hey guys i read everything but was wonderin since im gonna also have a lt4 hot cam or a zz4 cam if i would need bigger injectors or what.
SiCkRs is offline  
Old 11-29-2010, 11:27 AM
  #217  
Junior Member
 
Join Date: Apr 2010
Location: LEWISVILLE TX
Posts: 5
Car: 1991 CAMARO RS
Engine: TBI 350
Transmission: AUTOMATIC
Re: How to: 305 To 350 swap....everything you need to know

what year of caprice will work?
jayhawk110 is offline  
Old 11-29-2010, 07:22 PM
  #218  
Junior Member
 
Fastcar92's Avatar
 
Join Date: Jun 2005
Location: Hemet, Ca.
Posts: 41
Car: 91 RS Camaro
Engine: 350
Transmission: 5 Speed
Axle/Gears: 3:08
Re: How to: 305 To 350 swap....everything you need to know

you still never ansered my questioned my question. Is the ECM the silver box that the chip goes IN?????????????????????????
Fastcar92 is offline  
Old 12-01-2010, 03:18 PM
  #219  
Junior Member
 
Join Date: Apr 2010
Location: LEWISVILLE TX
Posts: 5
Car: 1991 CAMARO RS
Engine: TBI 350
Transmission: AUTOMATIC
Re: How to: 305 To 350 swap....everything you need to know

yes it's on the passenger side behind the kick board. it is velcrowed in.
jayhawk110 is offline  
Old 12-02-2010, 10:11 AM
  #220  
Junior Member
 
Fastcar92's Avatar
 
Join Date: Jun 2005
Location: Hemet, Ca.
Posts: 41
Car: 91 RS Camaro
Engine: 350
Transmission: 5 Speed
Axle/Gears: 3:08
Re: How to: 305 To 350 swap....everything you need to know

Thank you very much, it seams like pullin teeth just to get that info, I have 2 of the 305 ECM units for sale and Im selling my 91 RS camaro too!!
Fastcar92 is offline  
Old 12-02-2010, 11:43 AM
  #221  
Junior Member
 
Join Date: Apr 2010
Location: LEWISVILLE TX
Posts: 5
Car: 1991 CAMARO RS
Engine: TBI 350
Transmission: AUTOMATIC
Re: How to: 305 To 350 swap....everything you need to know

forgive me and my forgetfelness but what is a 91 camaro tool? i have a 91 rs.
jayhawk110 is offline  
Old 12-02-2010, 06:48 PM
  #222  
Junior Member
 
Fastcar92's Avatar
 
Join Date: Jun 2005
Location: Hemet, Ca.
Posts: 41
Car: 91 RS Camaro
Engine: 350
Transmission: 5 Speed
Axle/Gears: 3:08
Re: How to: 305 To 350 swap....everything you need to know

It reads too, dork
Fastcar92 is offline  
Old 01-09-2011, 05:14 AM
  #223  
Supreme Member
iTrader: (2)
 
KITT1983's Avatar
 
Join Date: Mar 2008
Location: Boston, MA
Posts: 2,801
Car: 1983 Pontiac Trans Am Daytona 500
Engine: Crossfire 305ci V8
Transmission: Jasper 700R4 4 speed Automatic
Axle/Gears: 3.23 limited slip/posi
Re: How to: 305 To 350 swap....everything you need to know

thanks for the great info
KITT1983 is offline  
Old 01-16-2011, 12:57 AM
  #224  
Junior Member
 
Join Date: Jan 2011
Posts: 1
Re: How to: 305 To 350 swap....everything you need to know

Will this work on a 1989 trans am?
jayjayrmz250 is offline  
Old 01-24-2011, 07:45 PM
  #225  
Junior Member
 
weirdoe's Avatar
 
Join Date: Jan 2011
Posts: 4
Re: How to: 305 To 350 swap....everything you need to know

hello i have a question? i have a 1989 camaro rs tbi 305. but i also had a 1986 z28 305 which i took out and had it rebuilt to a 350 tpi. now i wrecked the car but kept my motor will it work if i take the manifold off my tbi and swap it for my tpi i wanna put my tbi manifold on my 350 tpi motor. so is there anything as far as electrical work that i will have to do will it run like it did wen it was tpi?
weirdoe is offline  
Old 01-24-2011, 07:48 PM
  #226  
Junior Member
 
weirdoe's Avatar
 
Join Date: Jan 2011
Posts: 4
Re: How to: 305 To 350 swap....everything you need to know

hello i have a question? i have a 1989 camaro rs tbi 305. but i also had a 1986 z28 305 which i took out and had it rebuilt to a 350 tpi. now i wrecked the car but kept my motor will it work if i take the manifold off my tbi and swap it for my tpi i wanna put my tbi manifold on my 350 tpi motor. so is there anything as far as electrical work that i will have to do will it run like it did wen it was tpi?
weirdoe is offline  
Old 01-24-2011, 10:52 PM
  #227  
Junior Member
 
Join Date: Apr 2010
Location: LEWISVILLE TX
Posts: 5
Car: 1991 CAMARO RS
Engine: TBI 350
Transmission: AUTOMATIC
Re: How to: 305 To 350 swap....everything you need to know

yes but you have to switch sensors and fuel injectors out to 350, and the wiring harness. one more thing the computer.
jayhawk110 is offline  
Old 01-27-2011, 06:29 PM
  #228  
Junior Member
 
weirdoe's Avatar
 
Join Date: Jan 2011
Posts: 4
Re: How to: 305 To 350 swap....everything you need to know

Originally Posted by jayhawk110 View Post
yes but you have to switch sensors and fuel injectors out to 350, and the wiring harness. one more thing the computer.
thanks bro so i can got to the junk yard and get these things? or shud i by them brand new
weirdoe is offline  
Old 01-28-2011, 03:39 AM
  #229  
Junior Member
 
Join Date: Apr 2010
Location: LEWISVILLE TX
Posts: 5
Car: 1991 CAMARO RS
Engine: TBI 350
Transmission: AUTOMATIC
Re: How to: 305 To 350 swap....everything you need to know

the wiring harness you can get on craigslists. i would buy everything else new. don't cut corners it will come back to bit you.
jayhawk110 is offline  
Old 01-28-2011, 05:18 PM
  #230  
Junior Member
 
Join Date: Jan 2011
Location: FL
Posts: 10
Car: 91 Z28 Camaro
Engine: 305 L03 TBI
Transmission: modified 700r4
Axle/Gears: stock
Re: How to: 305 To 350 swap....everything you need to know

AWESOME!!!! Im working on a 305 to 350 swap now thanks for all the info.
Pitbull91z28 is offline  
Old 02-05-2011, 11:55 PM
  #231  
Junior Member
 
weirdoe's Avatar
 
Join Date: Jan 2011
Posts: 4
Re: How to: 305 To 350 swap....everything you need to know

Originally Posted by jayhawk110 View Post
the wiring harness you can get on craigslists. i would buy everything else new. don't cut corners it will come back to bit you.
so wat sensors are you talkin about bro and im usin an aftermarket air filter without and mass air sensor
weirdoe is offline  
Old 03-19-2011, 09:00 AM
  #232  
Junior Member
 
Join Date: Feb 2011
Posts: 1
Re: How to: 305 To 350 swap....everything you need to know

I followed these instructions exactly and everything worked great. Swapped a 350 with a mild "RV" cam (about 265 hp) into a 305, 1988 firebird formula, 5 speed manual. Bought a autoprom from Moates, (those guys are great) used a anlu5369.bin to start out, tuned with TunerPro RT. This car runs better than it did new. Thanks to thirdgen.org!!!
jabohannon is offline  
Old 04-04-2011, 04:29 AM
  #233  
Member
iTrader: (1)
 
Join Date: Jul 2010
Location: New York
Posts: 171
Car: 84 Z28 Camaro
Engine: Z28,305
Transmission: 700R 4
Axle/Gears: stock
Re: How to: 305 To 350 swap....everything you need to know

where is the ESC module?
birdman_29 is offline  
Old 04-04-2011, 08:18 AM
  #234  
Member
iTrader: (2)
 
dollarbill425's Avatar
 
Join Date: Jan 2003
Location: Missouri
Posts: 140
Car: 89 Camaro RS
Engine: 350
Transmission: T5
Axle/Gears: 3.42
Re: How to: 305 To 350 swap....everything you need to know

Usually on the firewall.
dollarbill425 is offline  
Old 04-05-2011, 01:54 PM
  #235  
Junior Member
 
Join Date: Mar 2011
Posts: 21
Car: 1982 Camaro
Engine: 350
Transmission: Turbo 350
Axle/Gears: IDK
Re: How to: 305 To 350 swap....everything you need to know

I was wondering. Can my 82 Z-28 still run if I keep the stock ecm or ecu (Which ever one it's called)? I'm kinda short on money and the $500 for a tranny rebuilt put a huge dent in my funds.
Camaroteen is offline  
Old 04-08-2011, 11:05 PM
  #236  
Member
iTrader: (1)
 
Join Date: Jul 2010
Location: New York
Posts: 171
Car: 84 Z28 Camaro
Engine: Z28,305
Transmission: 700R 4
Axle/Gears: stock
Re: How to: 305 To 350 swap....everything you need to know

hey, I got a 355 in my 91 RS Camaro, I've changed the ESC module, knock sensor, and the fuel injectors all towards a 350. Module and knock sensor are order for a 91 Z28, I want to replace the computer chip with the same 91 Z28 as the rest. I called the dealership today and asked for one and they asked in return for the VIN number!!!! I need a vin # from a 91 Z28 with a 350, any takers to share???? Or is there a easier way? Oh I can call the salvage yard tomorrow and see if they have one. Any suggestions?
birdman_29 is offline  
Old 04-15-2011, 03:58 PM
  #237  
Senior Member
iTrader: (3)
 
insomniac's Avatar
 
Join Date: Jul 2010
Location: The Jersey Shore
Posts: 765
Car: 1991 Firebird Convertible
Engine: 5.7 L98
Transmission: 700R4
Axle/Gears: 3.45 9 Bolt Posi
Re: How to: 305 To 350 swap....everything you need to know

i got a 91 firebird 5.0 tbi if i just get a junk yard tbi 350 out of a caprice wouldnt that have the correct fuel injectors and knock sensor? cant i just pop it in and change the chip - maybe even the one that was with the motor? is the harness the same?

thanks

whats the stock horse power/torque from those 5.7 tbi's?
insomniac is offline  
Old 06-14-2011, 03:14 AM
  #238  
Junior Member
 
DrexRS's Avatar
 
Join Date: Mar 2011
Location: Oroville, CA
Posts: 77
Car: 1988 Trans Am
Engine: 305 TBI
Transmission: 5 Speed Manual Transmission
Axle/Gears: Stock
Re: How to: 305 To 350 swap....everything you need to know

Do you need the transmission from a 350 or will the 305 transmission work.
DrexRS is offline  
Old 06-14-2011, 10:29 AM
  #239  
Supreme Member
iTrader: (4)
 
Ozz1967's Avatar
 
Join Date: Dec 2005
Location: St. Cloud, MN
Posts: 4,729
Car: 1984 Trans Am
Engine: In progress 6.0 LS swap
Transmission: 4l60e with 3600 FTI converter
Axle/Gears: Zexel Torsen 3.73, 28-spline mosers
Re: How to: 305 To 350 swap....everything you need to know

Originally Posted by DrexRS View Post
Do you need the transmission from a 350 or will the 305 transmission work.
The transmissions were the same no matter if you have a 305 or a 350. Either you got the manual or the 700R4.
Ozz1967 is offline  
Old 06-24-2011, 06:29 PM
  #240  
Junior Member
 
Join Date: Jun 2011
Posts: 77
Re: How to: 305 To 350 swap....everything you need to know

what year of caprice do people usually get the police package chip from? only one they can find at the GM dealership is 305 chips
RicerEater78 is offline  
Old 06-25-2011, 08:34 PM
  #241  
Junior Member
 
Join Date: Jun 2011
Posts: 77
Re: How to: 305 To 350 swap....everything you need to know

quick question. im almost done with my car. ive got an 89 firebird formula thats had a 350 swap. i need to know, will caprice chips go right onto the stock ecm? ive read that i might have to switch the ecm out. and what year of caprice would be best? i need to know asap. thanks in advance!
RicerEater78 is offline  
Old 06-26-2011, 01:52 PM
  #242  
Member
 
hatemail72's Avatar
 
Join Date: Jan 2010
Location: Niagara Region Ontario Canada
Posts: 114
Car: this and Dodge Dakota Quad
Engine: 383 tbi
Transmission: 700 R4
Axle/Gears: 3-73
Re: How to: 305 To 350 swap....everything you need to know

My 305 is making a knocking sound after warm. I have sent the vehicle to a couple of garages and they quickly say it is a lifter issue but the one garage is puzzled {they are close to the house} no problem until warmed up or put in gear and a load {foot on brake a little throttle} then lifter sound becomes present with this being the case or the erratic issue. I question the need to pull the engine as it could be electrical i.e. Knock sensor. I am not a Mechanic just a licence Bodyman / weekend hobby enthusiast. I need your thoughts and guidance. I am impressed by BMmontieSS original Quote. Hoping to get a handle of this issue by utilizing the strength of the members. if the worst case situation is to pull the engine and get a crate 305-350 tbi Vortec Help and opinions appreciated

Matt
hatemail72 is offline  
Old 08-30-2011, 05:04 PM
  #243  
Junior Member
 
Join Date: Aug 2011
Posts: 1
Re: How to: 305 To 350 swap....everything you need to know

I have a 1988 chevy caprice 350 5.7L carburated. I took out a 305 carburated and rebuilt the heads from the 305 and put them on the 350. I set the timing to 6 degrees btdc and I get valve tap or pinging under load. Runs great besides that, don't know if I have to change the chip to a carburated engine or if they even have one. I changed out the knock sensor and the esc. Can you help? Thanks
peterlayton is offline  
Old 08-31-2011, 12:06 AM
  #244  
Supreme Member
iTrader: (4)
 
Ozz1967's Avatar
 
Join Date: Dec 2005
Location: St. Cloud, MN
Posts: 4,729
Car: 1984 Trans Am
Engine: In progress 6.0 LS swap
Transmission: 4l60e with 3600 FTI converter
Axle/Gears: Zexel Torsen 3.73, 28-spline mosers
Re: How to: 305 To 350 swap....everything you need to know

Originally Posted by peterlayton View Post
I have a 1988 chevy caprice 350 5.7L carburated. I took out a 305 carburated and rebuilt the heads from the 305 and put them on the 350. I set the timing to 6 degrees btdc and I get valve tap or pinging under load. Runs great besides that, don't know if I have to change the chip to a carburated engine or if they even have one. I changed out the knock sensor and the esc. Can you help? Thanks
Those 305 heads are going to raise your compression quite a bit, make sure you're running 93 octane.
Ozz1967 is offline  
Old 10-05-2011, 11:33 AM
  #245  
Junior Member
 
Join Date: Jul 2011
Posts: 42
Re: How to: 305 To 350 swap....everything you need to know

So i upgraded my stock 305 to a 350 and was oblivious until recently about all the other NEED to change parts, since i had the original 305 tbi should the ECM suffice and if so where should i get a good promm. If not where can i get both promm and ECM im an idiot so ya
Sparta00 is offline  
Old 10-05-2011, 12:30 PM
  #246  
Supreme Member
iTrader: (117)
 
Join Date: Aug 2009
Location: Central California
Posts: 1,553
Car: 92 Camaro RS
Engine: LO3
Transmission: T5
Axle/Gears: stock
Re: How to: 305 To 350 swap....everything you need to know

Your computer is fine. Read the first post on this thread
henryd3 is offline  
Old 10-05-2011, 12:39 PM
  #247  
Junior Member
 
Join Date: Jul 2011
Posts: 42
Re: How to: 305 To 350 swap....everything you need to know

I bought the block from a friend its a chevy 350 but neither of us know where it came form as well good strong block though and its compeltely rebuilt lol so my other question is as long as i follow this set up will I be ok and where can i find the chip for a 350
Sparta00 is offline  
Old 10-05-2011, 12:43 PM
  #248  
Junior Member
 
Join Date: Jul 2011
Posts: 42
Re: How to: 305 To 350 swap....everything you need to know

also went to the junkyard the guy had 350 TBI buicks there in abundance would there chip work?
Sparta00 is offline  
Old 10-05-2011, 12:51 PM
  #249  
Supreme Member
iTrader: (117)
 
Join Date: Aug 2009
Location: Central California
Posts: 1,553
Car: 92 Camaro RS
Engine: LO3
Transmission: T5
Axle/Gears: stock
Re: How to: 305 To 350 swap....everything you need to know

The chip will ONLY work if it's also out of an 8746 computer which was used in Fbodies and Caprices according to the post you just read. If that's the computer in the Buicks then it will work
henryd3 is offline  
Old 10-05-2011, 12:54 PM
  #250  
Junior Member
 
Join Date: Jul 2011
Posts: 42
Re: How to: 305 To 350 swap....everything you need to know

so its gotta be that caprice chip or nothing lol gotcha
Sparta00 is offline  

Thread Tools
Search this Thread
Quick Reply: How to: 305 To 350 swap....everything you need to know


Advertising
Featured Sponsors
Vendor Directory

Contact Us Advertising Cookie Policy Privacy Statement Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: