87 engine swap 305 to 350 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Low87 · 02-24-2005, 05:29 PM

Wow, it's been a while. Wierd to come back to this new look.

Anyway, I've finally got the money to trade out the tired 305 in my 87. I want to pick up a Goodwrench 350. My question is, what will I need to change to go to a 350? Will the TBI and chip need adjustment?

Any help would be appreciated!

piecesparts · 02-24-2005, 08:04 PM

I had a buddy put a 350 in his Camaro where the 305 used to sit. He used the 350 knock sensors and that is all he changed from the hook up. He kept the TBI unit and the computer. It ran like a striped ape after the change.

Jason Spears · 02-24-2005, 08:16 PM

You will need a new prom set up for your specific truck (motor, trans and gear ratio). You will not need a new calpak. I'd like to give a custom burnt chip a try but I don't think a GM prom is too expensive (less than $100).

I'm not sure about the knock sensor(I've heard this before but I'm not 100%)but you will have to change to 350 fuel injectors. I think everything else is the same.

I want to do the same swap to my '87 among many other things. Good luck.

**Captkaos** · 02-25-2005, 01:23 PM

Talk about MIA.
The 5.7L uses 55lb/hr (13psi) injectors compared to the 40lb/hr on the 5.0L.
They are the Orange/Black coded injectors, PN is GM 5235206.

It will [i/probably[/i] work on the 350, but you won't see full potential, and I would recommend getting the chip and 350 injectors.

This will alow you to do realtime tuning for the chip:
http://www.xtronics.com/memory/pktROM.htm if you get say the Tunercat software with it: http://www.tunercat.com/tnr_desc/do_tc.html

Low87 · 02-25-2005, 03:00 PM

Thanks guys. Yeah Chris, life has precendented internet. I may stick with my TBI for now, my next purchase is going to be a Holley TBI replacement. I'll just be happy to not have to add oil every time I get gas!
How's the project going?

**Captkaos** · 02-28-2005, 06:22 PM

Quote:

Originally Posted by Low87

Thanks guys. Yeah Chris, life has precendented internet. I may stick with my TBI for now, my next purchase is going to be a Holley TBI replacement. I'll just be happy to not have to add oil every time I get gas!
How's the project going?

It is almost stagnet at this point. Jeff and Ken are trying to turn the heat on me though. I currently have to many irons in the fire.

Jonboy · 02-25-2005, 03:49 PM

you could probably score the whole ECM and TBI off of any Suburban at a pick a part. They are pretty thick in the yards down here.

bigblock73 · 02-25-2005, 04:30 PM

Welcome back Greg, long time no see! Glad to see you wrenching on the truck again too.

Low87 · 02-28-2005, 12:36 AM

Thanks for the welcome back Jeff. I've been driving the piso all along, just haven't been doing anything to it. I'll be back around as time permits.

AirMale · 02-28-2005, 01:01 PM

welcome back

pedrofixlater · 03-05-2005, 01:18 PM

your 350 uses bigger injectors, your engine may run alittle lean and you wont see max performance the knock sensor is basically the same.

02-24-2005, 05:29 PM	#1
Low87 been here longer than Liz Join Date: Feb 2000 Location: Broken Arrow, OK Posts: 2,437	87 engine swap 305 to 350 Wow, it's been a while. Wierd to come back to this new look. Anyway, I've finally got the money to trade out the tired 305 in my 87. I want to pick up a Goodwrench 350. My question is, what will I need to change to go to a 350? Will the TBI and chip need adjustment? Any help would be appreciated! __________________ ~Greg~ Mac's Garage '87 SWB 6/8 drop "Piso" '08 CCSB Silverado DD the departed '89 GMC K5 Jimmy 4x4 "Rusty Nuts" '77 Chevy K5 Blazer 2wd '83 Chevy stepside "You get what you pay for" - Mike 'swervin ervin' Ervin

02-25-2005, 01:23 PM	#4
Captkaos www.73-87chevytrucks.com Join Date: Dec 1999 Location: Birmingham, AL Posts: 6,935	Talk about MIA. The 5.7L uses 55lb/hr (13psi) injectors compared to the 40lb/hr on the 5.0L. They are the Orange/Black coded injectors, PN is GM 5235206. It will [i/probably[/i] work on the 350, but you won't see full potential, and I would recommend getting the chip and 350 injectors. This will alow you to do realtime tuning for the chip: http://www.xtronics.com/memory/pktROM.htm if you get say the Tunercat software with it: http://www.tunercat.com/tnr_desc/do_tc.html __________________ Chris Lucas 1973 Chevy C-10 1978 GMC Jimmy (2WD) - SOLD 1987 R10 twin turbo LS 1991 R3500 SRW CrewCab 1985 K5 diesel swapped project 1989 K5 2WD conversion w/ Vette susp Project Captkaos Customs 73-87chevytrucks.com

02-25-2005, 03:00 PM	#5
Low87 been here longer than Liz Join Date: Feb 2000 Location: Broken Arrow, OK Posts: 2,437	Thanks guys. Yeah Chris, life has precendented internet. I may stick with my TBI for now, my next purchase is going to be a Holley TBI replacement. I'll just be happy to not have to add oil every time I get gas! How's the project going? __________________ ~Greg~ Mac's Garage '87 SWB 6/8 drop "Piso" '08 CCSB Silverado DD the departed '89 GMC K5 Jimmy 4x4 "Rusty Nuts" '77 Chevy K5 Blazer 2wd '83 Chevy stepside "You get what you pay for" - Mike 'swervin ervin' Ervin

02-25-2005, 03:49 PM	#7
Jonboy Slots go on anything! Join Date: May 2003 Location: Richardson, TX Posts: 5,957	you could probably score the whole ECM and TBI off of any Suburban at a pick a part. They are pretty thick in the yards down here. __________________ 1974 Jimmy- 5.3/4L80e/NP241

02-25-2005, 04:30 PM	#8
bigblock73 yeller Join Date: Oct 2001 Location: Twin Cities Posts: 13,826	Welcome back Greg, long time no see! Glad to see you wrenching on the truck again too. __________________ Jeff 73-87.com 73-87.com Facebook page 73-87 cab corner 6x9 speaker brackets for sale 67-72 cab corner speaker brackets for sale 47-54 cab corner speaker brackets for sale

02-24-2005, 08:04 PM	#2
piecesparts Parts and more parts Join Date: Nov 2003 Location: Lebo, Kansas (middle of nowhere Posts: 6,821	I had a buddy put a 350 in his Camaro where the 305 used to sit. He used the 350 knock sensors and that is all he changed from the hook up. He kept the TBI unit and the computer. It ran like a striped ape after the change.

02-24-2005, 08:16 PM	#3
Jason Spears Registered User Join Date: Dec 2002 Location: Stoney Creek, ON Posts: 89	You will need a new prom set up for your specific truck (motor, trans and gear ratio). You will not need a new calpak. I'd like to give a custom burnt chip a try but I don't think a GM prom is too expensive (less than $100). I'm not sure about the knock sensor(I've heard this before but I'm not 100%)but you will have to change to 350 fuel injectors. I think everything else is the same. I want to do the same swap to my '87 among many other things. Good luck.

02-28-2005, 12:36 AM	#9
Low87 been here longer than Liz Join Date: Feb 2000 Location: Broken Arrow, OK Posts: 2,437	Thanks for the welcome back Jeff. I've been driving the piso all along, just haven't been doing anything to it. I'll be back around as time permits. __________________ ~Greg~ Mac's Garage '87 SWB 6/8 drop "Piso" '08 CCSB Silverado DD the departed '89 GMC K5 Jimmy 4x4 "Rusty Nuts" '77 Chevy K5 Blazer 2wd '83 Chevy stepside "You get what you pay for" - Mike 'swervin ervin' Ervin

02-28-2005, 01:01 PM	#10
AirMale Senior Member Join Date: Jan 2003 Location: Atlantic City, NJ Posts: 1,073	welcome back __________________ 86 SWB 9.0 LITER T-400-OD 4.11 eaton-4/5 drop Best 1/4 12.51 @112mph no traction

03-05-2005, 01:18 PM	#11
pedrofixlater 75 STEPSIDE Join Date: Mar 2005 Location: Suffolk, VA Posts: 92	your 350 uses bigger injectors, your engine may run alittle lean and you wont see max performance the knock sensor is basically the same. __________________ Pete 75 Chevy Stepside 70 Buick Skylark/GS



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