I have an 85 vette 230hp 350 with a 700r4 trans . The trans was just rebuilt and come out excellent. The engine has 170k miles on it it runs great but I just cannot live with 12 to 14 mpg in town. GM is producing these new v6 and small cu. in. v8 engines. Is this a hard swap to do? Has any one done this before . Can any body help me1
there are considerable differences in the new vs. old powerplants. You may need to have some mounts fabbed etc. you'll also likely need a custom program for the ecm, especially if you wanted to adapt a late model pcm in use with the 700 r4.. I'd start with some of the aftermarket conversion companies ...like street legal performance... they did a lot of retro work , electronics wise when going to TPI was the big rage. I know you say your motor runs well and all , but I bet you'd be surprised at how much blow-by you're getting past the rings at 170K miles as well as poor valve seat sealing...those two factors suck fuel on these motors BIG time.. as does all the "little vacuum leaks around the plenum and tubes if they don't get realed vey often. as far as hard parts.... exhaust configuration for the manifolds is not like the older motors if you go to a gen 3 small block ...custom exhaust or aftermarket conversion time. not completely sure a 700 will bolt to these either as most of the gen 3's use a full circle bolt pattern at the bell housing. Haven't played with these updates first hand ,, gue$$ anything can be accopmli$hed with enough ca$h though. I'd want to see some leak down numbers for your motor before you decide. a good solid rebuild and reprogram might net you more mpg than you might think . any one else played with these ?
I agree with all that was said above.Your car should be getting alot better milage then that.I have a 87 z28 that I just put in a new 350.this car is now getting 23 to 24 on the highway,and a solid 18 in town.This is better than the old 305 was getting.I would look at a good rebuild for your 350.It would be alot easeyer and a lot cheaper.And a lot faster.Good luck.
you cant be serious about putting a 6 cylinder in a vette?? get the 350 rebuilt and if 20 mpg isnt enough sell the vette and buy a chevette! dont forget when an 85 vette was built gas was like a dollar a gallon!!
heheheh thanks for the giggle............... but don't forget , the first vettes WERE 6's, and in 1985 people were bi**hin' about how expensive gas was. Some things never change eh?? ( but I agree that a v-6 in an 85 would be a sacrilage)
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