Chevy 4.3

[Daviticus]

I can't say I've "built" a 4.3, but my father and I dropped a Comp Cams Magnum 270HR cam into our '03 Bayliner Capri with the Merc 4.3, then tossed a Paxton Novi1000 onto it in a blow-thru setup with the Merc factory 2-barrel, rejetted of course. If I remember right it had Vortec heads on it from Merc as well. It would pull beautifully from 2000 to 6300, full boost was 7psi by 3200, and we had a boost-valve open after that to keep it safe, as the blower was already pretty far underdriven. We had an air-to-liquid intercooler for it as well, and I'm sure you already know the source of the cooling medium.

I'll tell ya, getting on a wakeboard behind that boat was a suicide mission after that build.

 

[Tacoma]

To bring this back up...

I've got Shawn's hoopty now and he wasn't kidding. It's pretty snappy. Around town it's a slingshot, I love it. Highway it's smooth and unstrained, though acceleration above 70 isn't overwhelming-- but it goes, and it keeps up. I think when I get it in the FJ40 I will love it quite a bit more than the F engine dog that's on the stand ready to go.

Apparently cams are the hot ticket for these. I'm looking into it... Also have a later long block w/the lame balancer and bike-sprocket timing "gear". But it should do a little better with the newer heads.

First recorded tank was 18.2mpg in mostly city driving (very short trips, less than 10mi round trips-- warmed up though) and one trip to Salt Lake loaded up and at 70-80mph. I can live with that.


anyway.

 

[notajeep]

I have one in my buggy, and I've had some machine work done to it.... it is bored out .060, they is not a sroker crank avail for the 4.3, but I had an off-set grind done on mine to get a little more stroke. Then I added some falt top pistions and a performer intake and a TBI spacer. Edlebrock burnt me a custom chip (this is included in all their TBI intakes) and I added an edlebrock cam as well. All in I have about $2k invested and put out about 300-325 HP at the crank. Is this better than a SBC? I don't know.... I do worry some about the offset grind and high RPMs, but I just try to watch my right foot. Going on a year now with this set up and it os working well for me.

 

[Gravy]

dang! maybe I'll keep this little 4.3 TBI for the wife's YJ

 

[rholbrook]

Everyone has their opinion. I spoke to a guy from Tennesee that makes the drive to Moab every Easter and averages over 20MPG on the highway. He loves it and would never put a V8 in his. I spoke to a guy at Winter on The Rocks who has a 350 in his jeep and wishes he would have put the 4.3 in his to reduce the weight. He never really mashes it hard enought to require the 2 extra lungs. I am still trying to decide what to do with my 97 TJ.

 

[Tacoma]

Well... I have to say I'm much more pleased than I thought I would be. I'm trying to decide now whether to keep the CPI setup or get an older TBI setup... mostly curious about the ease of adapting the newer harnees v. The TBI stuff. Another cool stock feature I like for the swap is the factory oil filter remote... that will be nice.