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BigBlocksRule · 11-07-2012, 08:20 AM

Tear down an old carb'd engine, then do the same to a TBI or MPFI engine. Difference in cylinder wear will make you a TBI fan, quick. All the older blocks I tear down have a significant ridge at the top of the bore from wear...almost every TBI or MPFI engine I've torn down still has visible hone marks in the bores. A small part of this is due to lighter ring pressure against the cylinder walls, but the majority is the TBI. With a decently tuned TBI, you never get fuel wash down the cylinder walls, you never flood out, your engine is metered fuel as it needs it and it's monitored by the O2 sensor.
And you can get a TBI harness that will let you run a 4L80E tranny for around $300. That in itself would weigh heavily on my decision. I'm converting an '85 1-ton dually to TBI for just these reasons.

11-07-2012, 08:20 AM	#17
BigBlocksRule Registered User Join Date: Jun 2008 Location: Lubbock, TX Posts: 2,047	Re: Tired of TBI issues, what size carb??? Tear down an old carb'd engine, then do the same to a TBI or MPFI engine. Difference in cylinder wear will make you a TBI fan, quick. All the older blocks I tear down have a significant ridge at the top of the bore from wear...almost every TBI or MPFI engine I've torn down still has visible hone marks in the bores. A small part of this is due to lighter ring pressure against the cylinder walls, but the majority is the TBI. With a decently tuned TBI, you never get fuel wash down the cylinder walls, you never flood out, your engine is metered fuel as it needs it and it's monitored by the O2 sensor. And you can get a TBI harness that will let you run a 4L80E tranny for around $300. That in itself would weigh heavily on my decision. I'm converting an '85 1-ton dually to TBI for just these reasons.