Do I absolutely need my chip tuned/reprogrammed?
#1
Do I absolutely need my chip tuned/reprogrammed?
Hello all! This is my first time posting so I'll try to make this as clear and detailed as possible. I have spent hours, days, weeks, months, and years searching this site and have managed to make it this far with all my search results but right now I'm a little stumped and was hoping all you third gen geniuses could help me!
I have a 1987 Trans Am GTA 5.7L 350 TPI with a brand new GM L31R engine from Summit I just finished putting in but it is still not running 100%! I did NOT use the vortec heads it came with and took those off and put on the regular stock cast iron heads (casting #10239906) so I didn't have to track down a discontinued/expensive vortec TPI intake manifold. I did leave the L31R cam in there though and I'm starting to think I should have removed it and put in the stock L98 cam from my old block because it is idling rough and will stall at stop signs/stop lights and I'm getting a lot of unburned fuel dumped into the exhaust and it will not pass California smog and I cannot get my registration tags until I get this fixed and running properly. I was hoping it would all be done and this would be my new daily driver for now but apparently I'm missing something!
My first question is: After much more research I learned that I probably need the chip to be reprogrammed with the different cam but is this the correct fix? Or should I make more work for myself and take out this L31R cam and put in the old L98 cam?
My second question is: are there other parts that might help this run better like different spark plugs maybe? Right now I have new AC Delco R43TS plugs in there that I think are for the L98 but not sure if they are the right ones for this L31R engine, or if it doesn't make a difference since I don't have the vortec heads on there.
Any help is GREATLY appreciated! I've been out of work for both my jobs for a couple weeks now since I'm car-less and this car is losing me tons of money! Just need it to pass smog so I can think about selling it already so I can consider a newer daily driver (anyone interested in buying? lol) Along with the swap I have new plugs, plug wires, Bosch 22lb fuel injectors, distributor, EGR valve, starter, alternator, battery, pretty much everything so it's a little frustrating that I need to dump more money into it and it's still not finished but that has been my entire relationship with this car: it's always something else! I'm hoping a chip reprogram is all it needs. Please let me know what you think and thanks for all the incredible info this website has provided me! I cannot tell you how many screen shots and diagrams and part numbers and member comments have helped me out so much along the way! Thank you again TGO!!!
I have a 1987 Trans Am GTA 5.7L 350 TPI with a brand new GM L31R engine from Summit I just finished putting in but it is still not running 100%! I did NOT use the vortec heads it came with and took those off and put on the regular stock cast iron heads (casting #10239906) so I didn't have to track down a discontinued/expensive vortec TPI intake manifold. I did leave the L31R cam in there though and I'm starting to think I should have removed it and put in the stock L98 cam from my old block because it is idling rough and will stall at stop signs/stop lights and I'm getting a lot of unburned fuel dumped into the exhaust and it will not pass California smog and I cannot get my registration tags until I get this fixed and running properly. I was hoping it would all be done and this would be my new daily driver for now but apparently I'm missing something!
My first question is: After much more research I learned that I probably need the chip to be reprogrammed with the different cam but is this the correct fix? Or should I make more work for myself and take out this L31R cam and put in the old L98 cam?
My second question is: are there other parts that might help this run better like different spark plugs maybe? Right now I have new AC Delco R43TS plugs in there that I think are for the L98 but not sure if they are the right ones for this L31R engine, or if it doesn't make a difference since I don't have the vortec heads on there.
Any help is GREATLY appreciated! I've been out of work for both my jobs for a couple weeks now since I'm car-less and this car is losing me tons of money! Just need it to pass smog so I can think about selling it already so I can consider a newer daily driver (anyone interested in buying? lol) Along with the swap I have new plugs, plug wires, Bosch 22lb fuel injectors, distributor, EGR valve, starter, alternator, battery, pretty much everything so it's a little frustrating that I need to dump more money into it and it's still not finished but that has been my entire relationship with this car: it's always something else! I'm hoping a chip reprogram is all it needs. Please let me know what you think and thanks for all the incredible info this website has provided me! I cannot tell you how many screen shots and diagrams and part numbers and member comments have helped me out so much along the way! Thank you again TGO!!!
#2
Supreme Member
iTrader: (16)
Re: Do I absolutely need my chip tuned/reprogrammed?
Originally Posted by evlbeak
I've been out of work for both my jobs for a couple weeks now since I'm car-less and this car is losing me tons of money! Just need it to pass smog so I can think about selling it already so I can consider a newer daily driver (anyone interested in buying? lol) Along with the swap I have new plugs, plug wires, Bosch 22lb fuel injectors, distributor, EGR valve, starter, alternator, battery, pretty much everything so it's a little frustrating that I need to dump more money into it and it's still not finished but that has been my entire relationship with this car: it's always something else! I'm hoping a chip reprogram is all it needs. Please let me know what you think and thanks for all the incredible info this website has provided me! I cannot tell you how many screen shots and diagrams and part numbers and member comments have helped me out so much along the way! Thank you again TGO!!!
Best of luck.
- Rob
#4
Supreme Member
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Do I absolutely need my chip tuned/reprogrammed?
Are the valves adjusted correctly? Fuel PSI regulator ok? No raw fuel in the vac line? Timing set correctly? MAF working correctly?
It should run ok with that cam.
I'm running a big inch sbc with 245 afr heads, mini ram and a large solid roller on a stock tune right now.. no drivability issues, drove it all over this weekend.
It will be tuned soon.
It should run ok with that cam.
I'm running a big inch sbc with 245 afr heads, mini ram and a large solid roller on a stock tune right now.. no drivability issues, drove it all over this weekend.
It will be tuned soon.
Last edited by TTOP350; 10-23-2016 at 09:28 AM.
#5
Re: Do I absolutely need my chip tuned/reprogrammed?
Of course this is assuming there is no other malfunction.
BTW you swapped the heads but did you verify the combustion chamber size? How do you know what compression ratio you have?
12530283 - Chevrolet
Specs:
1986-2000 style block, 1pc rear seal 4 bolt mains -(No mechanical Fuel Pump Provision)
Nodular Iron Crankshaft
Powdered Metal Connecting Rods
Hypereutectic Pistons
9.4:1 Compression Ratio
Roller Camshaft-
Specs-
Intake Lift- .414"
Exhaust Lift-.428"
Intake Duration @.050"- 191
Exhaust Duration @ .050-196
Lobe Centerline-111
Last edited by ULTM8Z; 10-29-2016 at 09:57 AM.
#6
Supreme Member
Re: Do I absolutely need my chip tuned/reprogrammed?
You say you did not put on vortec heads but you also say use used the casting #10239906. Those are the vortec heads. The cam is the L31 is similar enough to the l98 so that is not your issue. What did you hope to gain with this swap we can help you out?