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

305 Tbi to 350 Tbi swap (need some help)

Thread Tools
 
Search this Thread
 
Old 01-09-2016, 06:50 PM
  #1  
Junior Member
Thread Starter
 
jpnc's Avatar
 
Join Date: Dec 2015
Location: NC
Posts: 17
Likes: 0
Received 0 Likes on 0 Posts
Car: 1988 GMC C1500
Engine: TBI 305
Transmission: 700R4
305 Tbi to 350 Tbi swap (need some help)

I have a 1991 GMC Sierra Pickup. It has a bad 305 Tbi engine in it.

I bought a 1993 350 Tbi engine that came from a 1993 Conversion Van. The block numbers are 10054727.

What will I have to change on the engine? I have the computer that was in the Van.

I have the wiring harness from the firewall (93 Van). I don't think that will work. Are the distributors the same?

It had an oil cooler on it. Would the oil pan be the same? I know I will have too change the dipstick, oil cooler, valve covers. What else will I have too change?....I think the 93' has roller lifters on it. not sure though. some 93-94
had them.

Thanks for any help!
Old 01-09-2016, 09:03 PM
  #2  
Supreme Member

iTrader: (1)
 
sofakingdom's Avatar
 
Join Date: Sep 2005
Posts: 26,050
Received 1,671 Likes on 1,268 Posts
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: 305 Tbi to 350 Tbi swap (need some help)

No idea.

This is a 92-92 Camaro/Firebird message board. That's what we know about here. Doesn't look like your question pertains to the matters we discuss here.
Old 01-09-2016, 09:54 PM
  #3  
Junior Member
Thread Starter
 
jpnc's Avatar
 
Join Date: Dec 2015
Location: NC
Posts: 17
Likes: 0
Received 0 Likes on 0 Posts
Car: 1988 GMC C1500
Engine: TBI 305
Transmission: 700R4
Re: 305 Tbi to 350 Tbi swap (need some help)

I just noticed that....I want post anything else...sorry
Old 01-12-2016, 06:01 PM
  #4  
Moderator

iTrader: (14)
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 43,169
Likes: 0
Received 35 Likes on 34 Posts
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Re: 305 Tbi to 350 Tbi swap (need some help)

Moved from Engine Swap forum. Might be enough "thirdgen related" stuff in here to discuss (I'll let the TBI gurus decide).
Old 01-13-2016, 01:01 AM
  #5  
Supreme Member

 
RFmaster's Avatar
 
Join Date: Jan 2007
Location: OC CA
Posts: 1,873
Likes: 0
Received 0 Likes on 0 Posts
Car: 75 Beast
Engine: 383 +EBL Flash
Transmission: 700R4
Axle/Gears: 4.11 with 33"
Re: 305 Tbi to 350 Tbi swap (need some help)

The 93-94 350 SBC used in trucks still had flat tappet cam shaft. Block probably has all the provisions for roller cam - spider bosses are present but may not have been drilled and tapped. To drop that 350 you'll have to transfer dipstick from 305 since vans use long reach handles.
Distributor are the same.
Double check donor van trany - if it uses 4L60E trany you'll have to keep your 305 ECM and find 350 CID EPROM calibration or burn your own. Post ECM service number from donor VAN
IRC Van throttle body uses a reverse cable. Just swap fuel pod (injector pod held with 3 torx screws) from 350 onto 305 base TB. Transplant onto 350 intake.

305 harness will work - the only delta is knock sensor (KS). Use EGRV, ESC and MAP support bracket from 305.

Surpetine belt system might be different - sorry it has been a while.

//RF
Old 01-13-2016, 06:35 AM
  #6  
Junior Member
Thread Starter
 
jpnc's Avatar
 
Join Date: Dec 2015
Location: NC
Posts: 17
Likes: 0
Received 0 Likes on 0 Posts
Car: 1988 GMC C1500
Engine: TBI 305
Transmission: 700R4
Re: 305 Tbi to 350 Tbi swap (need some help)

Thank you! RFmaster...for your time and information....It's tough trying to figure all of this out.

I have another question...How can I find the right PROM (chip) for the ECM. What Chip # do I look for? " 1227747 ARJT " I have a 1991 GMC Sierra pickup, it came with a 305 engine and a 700R4 transmission.

I'm installing a 1993 350 engine and a 700R4 transmission in the 91' GMC Truck

How can I burn my own chip? Can I get someone to burn a chip for me?

Thanks for any help!
Old 01-13-2016, 10:22 AM
  #7  
Supreme Member

 
RFmaster's Avatar
 
Join Date: Jan 2007
Location: OC CA
Posts: 1,873
Likes: 0
Received 0 Likes on 0 Posts
Car: 75 Beast
Engine: 383 +EBL Flash
Transmission: 700R4
Axle/Gears: 4.11 with 33"
Re: 305 Tbi to 350 Tbi swap (need some help)

The most common 1991 350 calibration (BCC #) for a truck with Automatic is ASDU. There are other BCC EPROMs that will work in 1227747 ECM - ASDZ is another BCC found in '91 truck applications. The simplest way to find one is to hit local JY and pick up a complete ECM. EBAY shysters sell them, but you'll pay top dollar for ECM. Alternatively post wanted EPROM on couple boards - here on TGO and http://www.gearhead-efi.com.
If you want a full custom DIY EPROM you'll need to get G2 adapter board and flash memory chip from Moates.
http://www.moates.net/g2-memory-adap...cing-p-36.html
There are plenty of options for EPROM burners for under $100. I bought my GQ-4X years ago from MCUmall. I do not know if Chinese EBAY copies work with 256 and 512k EEPROMs.

BCC Calibration memory images are readily available from gearhead website and elsewhere.
http://www.gearhead-efi.com/Fuel-Inj...Information-42

So if you need to make any EPROM changes this can be done with TP. There is a learning curve involved if you plan to go DIY EPROM. However, it is worth it if plan to swap cams, heads, etc. Just be ready for a journey!

//RF
Old 01-13-2016, 06:17 PM
  #8  
Junior Member
Thread Starter
 
jpnc's Avatar
 
Join Date: Dec 2015
Location: NC
Posts: 17
Likes: 0
Received 0 Likes on 0 Posts
Car: 1988 GMC C1500
Engine: TBI 305
Transmission: 700R4
Re: 305 Tbi to 350 Tbi swap (need some help)

Thanks RFmaster....I really do appreciate the information.

I'm really tired right now. It's been a back breaking day.

Could you answer some more questions for me later this week?


Thanks again,

JP
Old 01-13-2016, 06:50 PM
  #9  
Supreme Member

 
RFmaster's Avatar
 
Join Date: Jan 2007
Location: OC CA
Posts: 1,873
Likes: 0
Received 0 Likes on 0 Posts
Car: 75 Beast
Engine: 383 +EBL Flash
Transmission: 700R4
Axle/Gears: 4.11 with 33"
Re: 305 Tbi to 350 Tbi swap (need some help)

Okay - I'll try. PM if it is extensive.

//RF
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
philmcgroin
Interior Parts for Sale
7
03-27-2016 12:29 PM
WASyL
Tech / General Engine
25
01-17-2016 02:36 PM
birdman_29
Electronics
4
12-24-2015 04:23 AM
Iblis
Tech / General Engine
2
12-17-2015 04:37 PM
BrianH33478
Camaros for Sale
0
12-17-2015 03:05 AM



Quick Reply: 305 Tbi to 350 Tbi swap (need some help)



All times are GMT -5. The time now is 12:16 PM.