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Brad · 09-17-2007, 02:15 AM

Since you're going to rebuild either one, it really comes down to personal preference. I also wanted to say that it'll probably be cheaper overall to build the 305. I would make sure that either have a minimum of 9.0 compression. The reason all these old tired L6's get bad mileage is due to the poor compression ratios. Bump it up to about 9.5 and you'll get awesome mileage. That's what I'll be doing when the day comes. The trouble is, I'll be old and grey before my 6 needs a rebuild.
Btw, I'm getting 16.3 around town with an occasional 65mph highway trip and my engine has about 130K on the clock.

09-17-2007, 02:15 AM	#10
Brad Out of the carpool lane. Join Date: Jan 2000 Location: Clark Co, WA Posts: 5,672	Re: 305 v8 or 250 I6 for better mpg Since you're going to rebuild either one, it really comes down to personal preference. I also wanted to say that it'll probably be cheaper overall to build the 305. I would make sure that either have a minimum of 9.0 compression. The reason all these old tired L6's get bad mileage is due to the poor compression ratios. Bump it up to about 9.5 and you'll get awesome mileage. That's what I'll be doing when the day comes. The trouble is, I'll be old and grey before my 6 needs a rebuild. Btw, I'm getting 16.3 around town with an occasional 65mph highway trip and my engine has about 130K on the clock. __________________ 1968 C-10 SWB, 5.7 Vortec/700R4/3.73 posi, Torch Red 1968 Camaro, 250/Powerglide, all original (No, I'm not gonna drop a 350 in it!...Jeez!) 2000 Honda VFR in the faster yellow! 2008 Husqvarna TE-610 1967 C-10 SWB 'Six Appeal'-Gone but not forgotten... Last edited by Brad; 09-17-2007 at 02:16 AM.