Engine Swap Everything about swapping an engine into your Third Gen.....be it V6, V8, LTX/LSX, crate engine, etc. Pictures, questions, answers, and work logs.

1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Thread Tools
 
Search this Thread
 
Old 10-21-2015, 09:59 AM
  #1  
Junior Member
Thread Starter
 
Nickvs707's Avatar
 
Join Date: Oct 2015
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Is it possible to pass ca smog like this? I live in ca and i had my 92 RS for almost 2 years when it came time to get it smogged again for my registration renewal...here's where the problems started... It failed all 3 parts of the smog test. So the shop I took it to recommended a diagnostic which I went ahead with only to find out, in the technicians own words, " Vehicle failed smog for multiple reasons. Engine is burning excess amount of oil. I checked operation of pcv system and found valve to be operating correctly. I reinstalled pcv hose correctly in an attempt to burn oil, However, internal engine failure does not allow oil to be burned off. Oil is entering the combustion chamber thrush rings. Vehicle also failed smog for incorrect vacuum line routing. However, all mechanical issues must be addressed first. Recommend engine replacement and continue with diagnostic." Well I ended up paying a mechanic that my friend knows pretty well rebuild the 5.0 305 tbi that was in it bcuz I didn't have money to buy a whole new crate engine. Much less to pay a shop to do the labor. Well the guy I hired ends up swapping the whole motor out with a 350 5.7 L98 from a 89 firebird.....according to the number stamped on the block, the L98 thats now in it is supposed to be tpi. But its still got a tbi. Now, i don't know much about cars, but that just doesnt sound right to me....i mean, it does run, but will it pass ca smog? Any input or suggestions would help me immensly. Thanks

Last edited by Nickvs707; 10-21-2015 at 10:04 AM.
Old 10-21-2015, 10:10 AM
  #2  
Junior Member
Thread Starter
 
Nickvs707's Avatar
 
Join Date: Oct 2015
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Originally Posted by Nickvs707
Is it possible to pass ca smog like this? I live in ca and i had my 92 RS for almost 2 years when it came time to get it smogged again for my registration renewal...here's where the problems started... It failed all 3 parts of the smog test. So the shop I took it to recommended a diagnostic which I went ahead with only to find out, in the technicians own words, " Vehicle failed smog for multiple reasons. Engine is burning excess amount of oil. I checked operation of pcv system and found valve to be operating correctly. I reinstalled pcv hose correctly in an attempt to burn oil, However, internal engine failure does not allow oil to be burned off. Oil is entering the combustion chamber thrush rings. Vehicle also failed smog for incorrect vacuum line routing. However, all mechanical issues must be addressed first. Recommend engine replacement and continue with diagnostic." Well I ended up paying a mechanic that my friend knows pretty well rebuild the 5.0 305 tbi that was in it bcuz I didn't have money to buy a whole new crate engine. Much less to pay a shop to do the labor. Well the guy I hired ends up swapping the whole motor out with a 350 5.7 L98 from a 89 firebird.....according to the number stamped on the block, the L98 thats now in it is supposed to be tpi. But its still got a tbi. Now, i don't know much about cars, but that just doesnt sound right to me....i mean, it does run, but will it pass ca smog? Any input or suggestions would help me immensly. Thanks
Also, here's a list of everything that was installed on the L98 350 that's in it now...
Piston rings, rod bearings, main gaskets, valve springs, guides, valve seals, push rods, cam and lifters- Comp Cam 260H, cap and rotor, new timing chain, flywheel, spark plugs.
Old 10-21-2015, 10:24 AM
  #3  
Junior Member
Thread Starter
 
Nickvs707's Avatar
 
Join Date: Oct 2015
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Originally Posted by Nickvs707
Also, here's a list of everything that was installed on the L98 350 that's in it now...
Piston rings, rod bearings, main gaskets, valve springs, guides, valve seals, push rods, cam and lifters- Comp Cam 260H, cap and rotor, new timing chain, flywheel, spark plugs.
I guess my question is, wouldnt the emission hose routing be totally different?
Old 10-21-2015, 06:27 PM
  #4  
Junior Member
Thread Starter
 
Nickvs707's Avatar
 
Join Date: Oct 2015
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Originally Posted by Nickvs707
I guess my question is, wouldnt the emission hose routing be totally different?
Also, i would assume that the next step is to break in the engine so the rings seat properly. But im unsure of how to go about doing so. What would be the correct break in procedure?
Old 10-21-2015, 11:15 PM
  #5  
Moderator

iTrader: (1)
 
Kevin91Z's Avatar
 
Join Date: Jul 1999
Location: Orange, SoCal
Posts: 10,943
Received 19 Likes on 17 Posts
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Yes you can replace a 305 with a 350 in California and still pass smog.

But so many techs are afraid of anything that isn't stock, so its best if you don't tell the smog tech anything and just pretend it is still stock.

Since you're using the same TBI intake, all the emissions hoses route exactly the same. The engine size doesn't matter in regards to that.
Old 11-22-2015, 04:19 AM
  #6  
Junior Member
Thread Starter
 
Nickvs707's Avatar
 
Join Date: Oct 2015
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Originally Posted by Kevin91Z
Yes you can replace a 305 with a 350 in California and still pass smog.

But so many techs are afraid of anything that isn't stock, so its best if you don't tell the smog tech anything and just pretend it is still stock.

Since you're using the same TBI intake, all the emissions hoses route exactly the same. The engine size doesn't matter in regards to that.
Do I need to swap the ecm and/or prom chip with one from a 89 firebird w/ a 350?
Old 12-12-2015, 01:22 PM
  #7  
Junior Member
Thread Starter
 
Nickvs707's Avatar
 
Join Date: Oct 2015
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Originally Posted by Kevin91Z
Yes you can replace a 305 with a 350 in California and still pass smog.

But so many techs are afraid of anything that isn't stock, so its best if you don't tell the smog tech anything and just pretend it is still stock.

Since you're using the same TBI intake, all the emissions hoses route exactly the same. The engine size doesn't matter in regards to that.
Do I need to swap the ecm and/or prom chip with one from a 350 Camaro/firebird? Bcuz the ECM/chip that's in it is still regulating everything for a 305, right???
Old 12-13-2015, 12:44 PM
  #8  
Supreme Member

iTrader: (14)
 
aliceempire's Avatar
 
Join Date: Nov 2008
Location: Milwaukee
Posts: 1,996
Received 140 Likes on 116 Posts
Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Originally Posted by Nickvs707
Do I need to swap the ecm and/or prom chip with one from a 350 Camaro/firebird??
No. The 350 PROM from a f body will be a tpi prom. Best would be to have a custom prom or something like EBL flash. Otherwise I'm pretty sure you could substitute a Caprice 350 TBI prom if you can find one. I had a TBI 350 in my car and still ran the 305 PROM for quite a while. Passed Wisconsin emissions at that time for what it's worth. Not recommending it, just saying it worked.
Old 02-20-2017, 03:24 AM
  #9  
Junior Member
Thread Starter
 
Nickvs707's Avatar
 
Join Date: Oct 2015
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Update- It passed smog.....barely. Now im trying to find the correct ESC module for a 350 tbi to replace the 305 tbi ESC that's in it now. I know that the old one from the 305 will suffice but I want to have the right one. Can I use one from any 350? as long as it was from a tbi? or does it have to have a certain number stamped on it? I just don't want to order the wrong one, seeing as they run about $90 a pop.
Old 02-20-2017, 06:24 PM
  #10  
Supreme Member

iTrader: (14)
 
aliceempire's Avatar
 
Join Date: Nov 2008
Location: Milwaukee
Posts: 1,996
Received 140 Likes on 116 Posts
Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Originally Posted by Nickvs707
Update- It passed smog.....barely. Now im trying to find the correct ESC module for a 350 tbi to replace the 305 tbi ESC that's in it now. I know that the old one from the 305 will suffice but I want to have the right one. Can I use one from any 350? as long as it was from a tbi? or does it have to have a certain number stamped on it? I just don't want to order the wrong one, seeing as they run about $90 a pop.
Just checking rockauto, I believe you can just buy a 350 esc and knock sensor for a caprice. Not all that expensive. I never changed them on mine, but mine is tpi now anyway.
Old 02-20-2017, 09:21 PM
  #11  
Junior Member
Thread Starter
 
Nickvs707's Avatar
 
Join Date: Oct 2015
Posts: 14
Likes: 0
Received 0 Likes on 0 Posts
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Originally Posted by aliceempire
Just checking rockauto, I believe you can just buy a 350 esc and knock sensor for a caprice. Not all that expensive. I never changed them on mine, but mine is tpi now anyway.
should I get one from an 89 (same year as my motor) or from a 92 ( same year as my car and ecm)?
Old 02-21-2017, 07:44 AM
  #12  
Supreme Member

iTrader: (2)
 
dmccain's Avatar
 
Join Date: Mar 2014
Location: South Ms
Posts: 4,422
Received 721 Likes on 490 Posts
Car: 89 Firebird
Engine: 355 TBI
Transmission: 700R4
Axle/Gears: 10 Bolt.Posi-3.73s
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

How does it run at the moment? Does it seem to have a lot more power?
Old 02-21-2017, 09:35 AM
  #13  
Supreme Member

iTrader: (14)
 
aliceempire's Avatar
 
Join Date: Nov 2008
Location: Milwaukee
Posts: 1,996
Received 140 Likes on 116 Posts
Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Originally Posted by Nickvs707
should I get one from an 89 (same year as my motor) or from a 92 ( same year as my car and ecm)?
They probably didn't change the engine at all but they'd often several make minor to calibrations in the ecm. If there is a difference in esc between the 2 years, I'd get the one to stay with the ecm. I doubt it makes any real difference but thats what I'd do
Old 02-21-2017, 09:57 AM
  #14  
Sponsor

iTrader: (92)
 
Tuned Performance's Avatar
 
Join Date: Dec 2004
Location: Mile High Country !!!
Posts: 15,407
Received 649 Likes on 573 Posts
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?

Most esc were used on 305s and 350s. The identifier is the three letters on the esc sticker.

Ones I know of

16126761 (ANRZ) is discontinued. Replaced with HKR for the 4.3l & 5.7L engines, and HKM for the 5.0l engines.

16022621 (BLH), is for 2.8l, 5.0l, and 5.7l engines.
You can always get a part number and then convert it to a acdelco number and use there web site application listing.

Last edited by Tuned Performance; 02-21-2017 at 10:27 AM. Reason: More info
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
KarlJ
TPI
11
11-13-2015 09:48 AM
dbrochard
Engine/Drivetrain/Suspension Parts for Sale
13
10-03-2015 12:43 PM
Glowsock
Tech / General Engine
2
09-11-2015 11:09 PM
Wylecoyote08
Engine Swap
3
09-08-2015 08:26 AM
Glowsock
Tech / General Engine
1
09-06-2015 06:40 AM



Quick Reply: 1992 RS -swapped 305 tbi with L98 tpi 350 from 89 firebird, but kept it tbi?



All times are GMT -5. The time now is 11:13 AM.