350 in place of 305 tbi ???
wowcars
11-29-2003, 12:23 AM
Okay, I've got a customized 91 Caprice wagon with 160,000 on it and the 305 is showing its wear. Although I am not dissapointed with the engine, it is weakening and leaking and burning oil. I don't want to rebuild the engine because this is my daily driver and can't afford the downtime it would take to overhaul it. I have a good 350 truck engine of similar vintage to just throw in. What I need to know is, What problems will I encounter? I know it will 'bolt up' to everything, but I don't know a whole lot about newer cars. Will the TBI be the same or will I need new injectors? Will the 700R trans act any different with the additional power? Will all of the sending units stay accurate? Any help would be appreciated. Thanks.
randy78
12-01-2003, 05:10 PM
no, 700r4 wont act any different unless you dont get TV cable adjustment right when it comes time to adjust it
you would want to get a 5.7L ECM and use the 5.7L TBI and injectors if at all possible or get 454 injectors.
everything else should be fine, if not then swap from the 305 as far as manifolds and accessories, etc.
you would want to get a 5.7L ECM and use the 5.7L TBI and injectors if at all possible or get 454 injectors.
everything else should be fine, if not then swap from the 305 as far as manifolds and accessories, etc.
ImmolatedEMT
02-14-2004, 12:03 PM
I have a '91 caprice classic sedan in good shape, and a '91 9C1 parts toilet. I'm going to try to swap motors this summer, after freshening up the 350. The Classic is great, but the 305 is enemic at best. Truth be told I'm scared to death to undertake the project because of the lack of info. on the '91 models. Anyway, good luck, and if you have any helpful links and could let me know, I'd really appreciate it.
Thanks
Phil
Thanks
Phil
quaddriver
02-14-2004, 01:56 PM
I have a '91 caprice classic sedan in good shape, and a '91 9C1 parts toilet. I'm going to try to swap motors this summer, after freshening up the 350. The Classic is great, but the 305 is enemic at best. Truth be told I'm scared to death to undertake the project because of the lack of info. on the '91 models. Anyway, good luck, and if you have any helpful links and could let me know, I'd really appreciate it.
Thanks
Phil
just bolt it in, the 4.3, 5.0 and 5.7 tbi unit is the same, the difference is the ecm, however, due to the rarity of B car 5.7 ECM TBI proms, the 5.0 ecm will work fine running a 5.7 (but there is a SLIGHT difference the other way around as the 5.7 spark table is a bit more advanced than the 5.0 so a 5.0 on a 5.7 ecm might knock, if running a 5.7 on a 5.0 ecm you will never knock...)
Thanks
Phil
just bolt it in, the 4.3, 5.0 and 5.7 tbi unit is the same, the difference is the ecm, however, due to the rarity of B car 5.7 ECM TBI proms, the 5.0 ecm will work fine running a 5.7 (but there is a SLIGHT difference the other way around as the 5.7 spark table is a bit more advanced than the 5.0 so a 5.0 on a 5.7 ecm might knock, if running a 5.7 on a 5.0 ecm you will never knock...)
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