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Myself · 03-09-2023, 11:20 AM

The stock 454 TBI is around 670cfm where the 350 TBI is only around 500. The 454 unit will bolt to the stock 350/305 intake manifold but you have to open up the holes as the 454 unit has a 2" bore vs the 350 at about 1 3/4". Bump up the fuel pressure to 20-25psi. It will run fine on the stock 350 ECU but a custom chip will work much better. The TBI really is a simple system that works well.

03-09-2023, 11:20 AM	#14
Myself Registered User Join Date: Oct 2005 Location: Northern Arkansas Posts: 1,128	Re: 1988 C1500 carb conversion The stock 454 TBI is around 670cfm where the 350 TBI is only around 500. The 454 unit will bolt to the stock 350/305 intake manifold but you have to open up the holes as the 454 unit has a 2" bore vs the 350 at about 1 3/4". Bump up the fuel pressure to 20-25psi. It will run fine on the stock 350 ECU but a custom chip will work much better. The TBI really is a simple system that works well.