The Stovebolt Site Forums The Shop Area Engine Shop V8 versus V6 swap

Seems that the biggest problem in putting a V8 into a stock truck is clearance with the steering box. Would a V6 fair any different? Anyone know. The more I think about the more I can see the same problem.

I would think it would be the same problem. Most V-6's are every bit as wide as a small block, just two cylinders shorter,
Scott

My first thought is the same as Scott's. But just for laugh's, what V-6 are you thinking about?

The 4.3 is really just a 350 with two fewer cylinders and its just as wide as the 350 where it matters.

But a 2.8 is a bit narrower and might fit without interference? I'm not sure why anyone would want a 2.8 in a truck, but perhaps it would fit?

I was thinking the 4.3 but it does seem like it would have the same problem. BUT you would have a lot of room in the front near the rad.
On this V8 note a friend built his own motor mounts for a 350 in his GMC and because it sits a bit higher than you usually see, there is no clearance problem.

The GM 2.8 V6 should burn in a molten pool of hellfire for all eternity - with the poor schmuck who designed it. :mad:

"The GM 2.8 V6 should burn in a molten pool of hellfire for all eternity - with the poor schmuck who designed it"

Come on...Tell us how you really feel! And don't hold back this time.

That poor schmuck's design powers every new vehicle GM makes other than saturn, saab, corvettes and trucks.

I put one in a jeep where a seized up 4 cylinder had been and it was a blast compared to the 4 cylinder. Interestingly same bolt pattern as an AMC 4 cylinder and a bolt in proposition with cherokee mounts. You can darn near put it in with your hands its so light. Amazingly it pulled down 24 mpg with 29 inch tall tires and 4.10 gears. Could pull a 3500 lbs center console boat to the launch with ease. Sadly it ran out of steam at 70 mph on the highway and could be a little scary when passing around town.

I think you could run a 3.4 S10 crate motor with a T5 behind it and have similar performance to a 235 with excellent fuel economy.

That being said, unless someone drops an mgb off at my front door, you'll never see a 60*v6 in one of my vehicles. Check out killerbv6 and you'll see what I mean.

I like the 4.3 - nice engine, even if you don't see the expected fuel savings over the 350. The last 2.8 I had, I wanted to drive the whole thing into a river and let it sink. It loved to stall going around left turns for some reason...

I had the 2.8 with multiport F.I. in a 85 Grand Am - My 2nd car. That thing flew and I drove it extremely hard (I was in my early 20s). It lasted 110k miles of serious abuse and lack of maintenance.

The last 2.8 I owned was a great motor. It only took one weekend to put it in and replace the awful one the car came with...

I think it would be a worst of both worlds swap. Not at all stock, doesn't look stock, but nothing about it makes it an improvement over the stock motor.

I have a 1951 Chevy that I got a great deal on a 4.3 L V-6 vortec with 4L60 transmission. It came from a 2000 Astro van that was rear-end totaled and has been in the yard for two years--means 3 years on the road and maybe 25kmiles max. Seems like we are trying to do the same thing. They put 350's all the time into old trucks and this is essentially a 350 with 2 cylinders chopped off. I have found a very good wiring guy, who is also very reasonable who is doing a custom harness for me (not a painless wiring harness but a custom job). I have all the computer and wiring from the astrovan; and all the periferal stuff like pumps. I have an A/C unit so the compressor is coming along too. The yard I got it from is letting me have anything else under the hood that I can use. I am trying to see if the cruise control and steering column will work. Anyway, I am just getting started with this and have a different guy with the body (it is off now) doing the body work (quite reasonably too.) I am not sure if you are trying to do the same thing as I am but if you are, we could compare notes. I already have a 1985 Camaro frame that I am using with nice clips on front so that the truck will drive more like a car. Anyway, there is much more I am learning. If you are going down the 4.3L path and want to modern creature comfort/fuel economy the truck like I am, it might be helpful.

If your wanting fuel economy, you may be dissappointed with the 4.3 . I had an o3 Jimmy with this motor that got 12 mpg in town, and currently have a AWD Safari with a 4.3 that gets 11 - 14 mpg all around. My stock 235 powered 62 w/ 4 spd averages 14 in town and 17 on the highway at 55mph. I'm looking forward to improvement with an overdrive I'm currently intalling along with new radial tires.

Retro51, you should get the trans from the donor too, as they are both controlled by the PCM. Simply taking the trans out of the equation will require some reprogramming and the need for a VSS (Vehicle Speed Sensor) box of some sort. The OBD-2 computers watch all kinds of stuff. Yours may want to see feedback from anti-lock sensors too. Just want you to have a handle on what to expect.
Doctasuds, the viscous BorgWarner AWD unit in the Astro resists even small differences in front/rear driveshaft speeds in a big way. Many folks with that unit run 8-10PSI more air in the front tires to get the diameters more precisely matched. This reduces rolling resistance. Could get you 2-4 MPG hiway. The best way to do it is to do roll-down tests on a flat smooth road somewhere and see wich combo rolls the farthest. Mikey

I drove a few 2.8's and was not impressed, they seemed underpowered. However, I had a 3.8 in an Oldsmobile and that was a very fast car. It also pulled our pop-up camper very well.

The 3.8 in your Olds was probably the Buick V-6 which was a very good motor. However, they quit making them in '88 or '89 or thereabouts. There was a supercharged version that made a lot of power.

The only guy I've talked to with a V-6 in an old truck said he was sorry he hadn't gone V-8 instead. He had a 4.3 in his.

I don't think that means its a bad idea, but you really need to have thought through what you want the truck to do before you choose a motor.

If you are going to do all that work for a swap make sure you are putting in a motor you will be satisfied with! I keep ending up with a big block as the only answer for me...

Mike,

I got the 4L60 transmission with the 4.3L and anything else I want under the hood--it is all pristine.

Steve

Hey Sub, your right on, my Olds with the 3.8 was a 1988, and my Dads Buick Park Avenue had the same engine it was an '89.

Just today I saw a maroon '88 Olds Cutlass Calais International wagon in a parking lot.

I had to look twice to be sure it was not the same car I once owned. I loved that car, but I sold it years ago because at the time maintaining a car with 170,000 plus miles just wasn't practical for me.

The car I was in today has 160,000 and I've no thoughts of replacing that one based on high miles....

That 3.8 Buick V-6 was great. Its the wrong motor for any of my trucks, but it was great in that car.