So has anyone here done a carb swap on a 96,97,98 5.7L vortec? can the ECM be programmed to run the trans, and what about the gauges EG speedo ECT. I know about the HEI distributor swap. Just looking for info at this time.
Carb swap questions???
- Thread starter kennythewelder
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mattbrat004
I'm Awesome
have to get a trans controller if you have a 4l60e. Don't think gauges would be affected by it
You don’t have to get a transmission controller. You just need to get Holley carb with the Holley throttle position sensor. The sensor will let the computer control the transmission. May need to swap distributor to an HEI
im doing the swap on my 96 Tahoe i just plugged in all my sensors all gauges work just make sure you hook up all the ground on it i swapped the trans to a 5 speed also but i have seen on youtube a swap he put a bracket on the passenger side on his carb and put the tpi sensor on
blacksport
I'm Awesome
why would you take of the FI....
Its a lot easier to make more HP with a carb. The FI system is limited to about 400 HP, and requires tuning (reprogramming) to achieve this, along with a lot of mods.why would you take of the FI....
How was gas milage effected? About to do the same swap
L31MaxExpress
I'm Awesome
Negatively but not as bad as one would think if it is well tuned. I think my average dropped about 1 mpg in the city and short trips but actually improved on the highway. That was running a carb on my L31 Express van for almost a year. It was a 650 cfm holley spreadbore q-jet replacement mechanical secondary double pumper with electic choke. I left the 0411 PCM to run the distributor, trans, fans, a/c compressor, etc. With the mechanical secondaries you can run the engine pretty hard without tipping into the secondaries and the second accelerator pump which saves alot of fuel especially with the smaller primaries. This setup is actually why the engine is getting a dual plane marine MPI intake on it. Lots of low-midrange grunt with a dual plane intake. I had a low profile carb plenum on top that tied into the stock MAF and air cleaner. I kept the coolant temp sensor, added a TPS and kept the MAP sensor. I did alot of datalogging plotting airflow and tuning the timing advance, carb and shift points to get it running well. It had excellent throttle response and low rpm manners once the engine had a little heat in it. The intake I chose was a marine intake with a water passageway under the carb to provide manifold heat. I ran it in the cooler months with hot water flowing through the manifold, in the warmer months it did not need it. With the 2,800 rpm converter I could actually stab the throttle to the floor just above idle and it never had a flat spot or a bog.
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Good to hear I'm still in the process of getting my tuned but can tell already I wont be going back to that spider lol
