v6 to v8 swap - Page 3

shadygrady · 06-08-2008, 03:59 PM

I have to agree with sneakysportsman on most of what he said.Like I stated carb would be your cheapest,easiest way.I personally prefer some sort of efi unit because thats what I`ve alwasys driven and am familiar with,but please do whatever you like.If your going to be hauling cars or stuff far you may want something a little better on fuel.A tbi system stock can be restrictive but since you said you want low end it may be for you.There are aftermarket tbi units that flow quite well.
You may or may not be able to use the same ecm but a prom recalibration is a must anytime you change cubic inches,number of cylinders,cam etc.
You can have someone burn you a custom prom to get you started.It prolly want be spot on,but what some do is buy an aldl cable and a cheap laptop off ebay and dattalogg.Buy hooking to the ecm you can record datta and send it to the person who did the chip and they can make more intelligent changes for what you need.I know of quite a few people who are tuneing there butts off on these old ecm`s at home.I`ve seen people getting right at 30 mpg from a tbi equiped 305,350 by evoking something called higway mode in the calibration that takes advantage of a low load,lean fuel condition at cruising speeds to accomplish it.Not sure how well it would work on a bb though.
As far as bolt ons not being worth the money I have to dissagree.I`m a firm believer that a good set of headers and a better than stock exhaust system is a must for any project.Better flowing intakes,carbs and such as well.I believe and have experienced that SOME bolt ons are very benificial.There are however alot of snake oils out there.Check out the prom burning and tuneing boards on that other site.Good luck with your project.Sneaky sportsman,hows your tpi project comeing?

Sneakysportsman · 06-08-2008, 07:47 PM

I ditched the TPI back in Feb because It kept burning out the driver in the ECM. 8 injectors were too much electrical load on the driver. I found a post on a different forum that covered the exact same problem I was having. I changed the cam in Feb and converted over to a carb. I tried to buy a TPS for a carb but HGLM electronics wanted to sell me a $1200 unit to control the trans. I bought a few parts from the hobby shop some alum angle from Lowes and duplicated the exact parameters from the original TBI sensor and Still used the Stock ECM to control the trans.

My fuel milage was 120 miles on 15 gals of prem gas, so once again I swaped back to the stock cam but kept the Vortec heads and flat top pistons. The timing needs a few more deg, but the computer does a good job of controll the ping on 87 gas. I get 23-25mpg.

mad_bomber · 06-11-2008, 10:35 AM

the mods done to my 6 are as follows: 0.020 over, 6in con. rods, 0.008 shaved off the heads, ported and polished, and valves out of a sb 400 and a lunati voodoo cam. i made the decision that im deff. going carb. and i shouldn't have to worry about the truck shifting right seeing as how i do that myself (NV3500 5sp)

06-08-2008, 03:59 PM	#21
shadygrady Full Member Join Date: Feb 2007 Location: Vicksburg,MS Posts: 34	I have to agree with sneakysportsman on most of what he said.Like I stated carb would be your cheapest,easiest way.I personally prefer some sort of efi unit because thats what I`ve alwasys driven and am familiar with,but please do whatever you like.If your going to be hauling cars or stuff far you may want something a little better on fuel.A tbi system stock can be restrictive but since you said you want low end it may be for you.There are aftermarket tbi units that flow quite well. You may or may not be able to use the same ecm but a prom recalibration is a must anytime you change cubic inches,number of cylinders,cam etc. You can have someone burn you a custom prom to get you started.It prolly want be spot on,but what some do is buy an aldl cable and a cheap laptop off ebay and dattalogg.Buy hooking to the ecm you can record datta and send it to the person who did the chip and they can make more intelligent changes for what you need.I know of quite a few people who are tuneing there butts off on these old ecm`s at home.I`ve seen people getting right at 30 mpg from a tbi equiped 305,350 by evoking something called higway mode in the calibration that takes advantage of a low load,lean fuel condition at cruising speeds to accomplish it.Not sure how well it would work on a bb though. As far as bolt ons not being worth the money I have to dissagree.I`m a firm believer that a good set of headers and a better than stock exhaust system is a must for any project.Better flowing intakes,carbs and such as well.I believe and have experienced that SOME bolt ons are very benificial.There are however alot of snake oils out there.Check out the prom burning and tuneing boards on that other site.Good luck with your project.Sneaky sportsman,hows your tpi project comeing? __________________ 1989 k1500 Cheyene 4x4,regular cab,swb,4.3 V-6.11`k&N Open element,smog pump delete,mechanical fan clutch to electric fan swap.flowmaster 2.5 dual exhaust.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
88 to 96 engine swap	Biofloc	Chevy Truck Forum	7	03-14-2008 11:51 PM
6.2/5.7 swap	project88	Chevy Truck Forum	3	11-26-2007 11:04 AM
tranny swap	NC4W	Chevy Truck Forum	2	04-15-2007 08:10 PM
Distributor swap	lb23	Chevy Truck Forum	3	04-01-2007 06:30 PM
LS1 swap	jobberone	Chevy Truck Forum	3	09-24-2005 06:25 PM

06-08-2008, 07:47 PM	#22
Sneakysportsman Senior Member Join Date: Jun 2007 Posts: 233	I ditched the TPI back in Feb because It kept burning out the driver in the ECM. 8 injectors were too much electrical load on the driver. I found a post on a different forum that covered the exact same problem I was having. I changed the cam in Feb and converted over to a carb. I tried to buy a TPS for a carb but HGLM electronics wanted to sell me a $1200 unit to control the trans. I bought a few parts from the hobby shop some alum angle from Lowes and duplicated the exact parameters from the original TBI sensor and Still used the Stock ECM to control the trans. My fuel milage was 120 miles on 15 gals of prem gas, so once again I swaped back to the stock cam but kept the Vortec heads and flat top pistons. The timing needs a few more deg, but the computer does a good job of controll the ping on 87 gas. I get 23-25mpg.

06-11-2008, 10:35 AM	#23
mad_bomber Junior Member Join Date: Jun 2008 Posts: 4	the mods done to my 6 are as follows: 0.020 over, 6in con. rods, 0.008 shaved off the heads, ported and polished, and valves out of a sb 400 and a lunati voodoo cam. i made the decision that im deff. going carb. and i shouldn't have to worry about the truck shifting right seeing as how i do that myself (NV3500 5sp)