A Chevy V8 to a Six......

[tarussell]

Just my $.02 worth .....

I agree with all who said that swapping anything for a few MPG's is an exspensive way to go for minimal gain. That being said I am one of those in-line six wierdo's who swapped out motors to run an in-line motor .

A 292 is a fine engine but fuel economy is not what it is known for. I have a 292 going in my daily driver Blazer that has LPG pistons , decked block , shaved head , marine cam grind , T.B.I. , intake and all the standard goody's but it WAS NOT cheap by any means . My intention was to gain serious bottom end torque not economy.

I am also installing a 6BT in my off-road Blazer and once again it ain't cheap ! If I was doing these motor swaps for better mileage than I would be waisting my time and serious coin expecting a return in better economy.

When it is all said and done I have built strong BBC's for far less money than I have got in my 292 - after market parts just ain't cheap for them......

Good luck in what ever you choose to do !

Tom

 

[bowtiepower00]

Hot Rod magazine has led a minor rebirth of the ol' sixes, lots of EFI conversions and even a good amount of hi-po builds with aftermarket stuff and even turbos, etc.

 

[MJD]

Hello, everyone. I am new to this place and I was looking for some info, and I saw this thread. The title caught my attention, since I have thought about a 292 six conversion in my 3/4 ton GMC. Anyway, I read about the idea of a 4bt conversion. My buddy did this conversion in his 1986 1/2 ton pickup. He used the original 700R4 tranny(with low-stall converter) and the stock axles(3.73 gear ratio). The engine came from a delivery van and I do not think that the entire project was very spendy. Anyway, he gets fuel mileage in the low 20's.

 

[Henry G]

Hey MJD, The 292 is primarily known as a stump puller. Major bottom end torque. Very easy to work on and leaves lots of room under the hood. I personally like the inlines. They're reliable and a basic an engine as you can get. With low gears not very fuel efficient but with tall gears not half bad. High teens to about 20. I have had only one and it ran really well. With some head work it will breathe better and a Clifford or Offy manifold with a two bbl or a 500 four bbl should do quite well for you with reasonable driving speed. I would go with 3" Magnaflow like on mine. It has a nice low tone with the long muffler. Whether long or medium or short they breathe the same. The only difference is the noise level. I love mine. The 292 is definately a work horse. Out here in the Northwest many people ran them for years going to logging sites or mining sites and pulled utility trailers with them. Cut fire wood and haul them to customers homes and etc. The 8s are faster but going up a long grade the big six does better properly set up. I have seen them in 25' class A motor homes and got about 14-15 with a 3 speed auto on the flats. The 8s got about 8-10. I almost bought it and wished I did. Oh well. I have MSD Off Road on my Chevy 350 with a K&N. I gained about 3 mpg. MAy put a six in mine. Time will tell. I wish you well and a great New Year. H.

 

[bear76]

MJD,

How did the 700r4 hold up to the 4bt? Did he run it for a long time?

Thanks

 

[88$PIT]

GM does make an inline 5 engine still. My grandfather has one in his Old's Bravada, and if I didn't know any better, I'd have guessed it had a small block in it. That thing produces gobs of torque...

You sure it's not the 4.2L in-line 6 instead?

 

[Clod_King]

I didn't know whether or not to repost to defend myself or not. So I will just explain why I posted that, because i know alot of those things are scams.

Buddy from work went to the house where the owners of the company live. The whole unit was made, designed, and thought up by the guys 19 year old kid. My buddy got to see all the prototypes, from the first one made out of PVC piping, all the way to the production model stainless steal unit.

The guys gave my buddy a 2.0L model to put in his car, in an attempt to hire him on as a sales man (they don't have any salemen, but get about 30 sales everyday on their website). He is sticking it in his dad's old minivan that cannot pass the E-test.

I will repost when I get the results. I just thought this would be a cheaper way to save on fuel.

I know the website is damn cheesey. the first time I saw it was when I posted the link. I don't know how they can make a living off of it, but they can.

I am not trying to pick any fights here. I hate it when threads get ruined by fighting. I just thought that it should be put out there. The guys sound reputable, and all, so I went for it. As I said before I'll let you know what happens to the minivan.

 

[Hogback Fabrication]

Breaking water apart into hydrogen and oxygen and then reburning it (hence, producing water again), even in the presence of hydrocarbons (gasoline) will net a neutral (0) power output. Factor in the inefficiencies of any system (ESPECIALLY internal combustion motors) and the fact that you have to use electricity (alternator generated, also pretty inefficient) to create the hydrogen means that you are wasting a bunch of energy for nothing. There is practically no way that "hydrogen injection" can do anything but cost you mileage.

If in fact it does clean carbon from the combustion chamber and valves, it could help mileage and performance. But then there are dozens of cheaper and more reasonable products that solve that problem.

Sales is certainly no guarantee of the effectiveness of their product. Look at the "Tornado". They have sold millions of that thing, that doesn't mean that it does anything

 

[MJD]

MJD,

How did the 700r4 hold up to the 4bt? Did he run it for a long time?

Thanks

It has held up well so far (knock on wood !). He has had the pickup on the road for a couple of years now and he has probably put about 10-20,000 miles on it, so it hasn't been too long. The transmission was pretty new when the conversion took place, and was behind a 305 with 200k. Aside from the torque converter, I think that he put a new governor in it. Otherwise, it is a stock transmission.

 

[Henry G]

A Chevy V8 to a six

Now I need some suggestions. On my 87 Chevy 1/2 Ton Pick up with a 350 TBI. While idling its throttles up and down without anybody touching it. I just put on a new double roller timimg chain (last night) a new harmonic balancer and a new water pump. It did it before these were done. The original chain was stretched so it needed replacing. I reset the timing and the computer and it still idles up and down. Any ideas? It has 93k original miles on it. Very frustrating. Maybe the distributor is bad but not sure. I have MSD Off Road and a K&N filter. I had a scan done a few weeks ago and all it showed was the voltage going up and down on the O2 sensor. The sensor tested good. Looks recent. Something is making it react to whatever is causing the problem. Got new 3" Magnaflow exhaust. TBI O rings??? Leaking injectors. Got to fix it. Thanks and Happy New year! H.

 

[tRustyK5]

If you're not looking to gain a boatload of power, but want to pretty much double your fuel mileage I'd look into swapping a 6.2 diesel into your K5. It's a plug and play swap in a K5, and makes about the same power as a 305 (acceleration wise)

CanmoreK5 on here has an '83 C10 pick-up, 6.2 diesel, 700R-4, 3.42 gears and 235/75 15's and he regularly gets 23 mpg with that. Several guys that frequent the Diesel forum here have reported 24 and 25 mpg on mostly freeway trips.

I had a carb'd 355 in my '81 Jimmy that saw best's of 10-11 on the freeway with 36's and 3.73's. I went one ton and 4.56's and saw my mileage drop to 8 no matter where I was driving. I swapped a used 6.2 into my truck, and added 39.5" TSL's at the same time...and saw my mileage pretty much double to 16.5 on the freeway and 15 in town.

4BT's and 6BT's are cool...but they are a lot more work and $$ to swap into one of our trucks.

I don't tow with my truck, and I don't drive it expecting to win any races. I can afford to drive it now, and I find it so nice offroad being injected.

Diesel's are even more simple than the old inline 6's too.

Rene