info for the inline 6 guys and girls

[292farmer]

just thought i'd pass on some information my bosses mechanic told me, a 1987 tbi unit off a 4.3l plus the dist, all swap to the 292-250 6cyl, all u need is a adapter to mount tbi to intake, the dist goes right in too.and he says the fuel curve on 87 4.3 wasnt much different then what a 250-292 would be. so not much tuning required. i guess at the dealership he worked at this was a popular upgrade in 87 for incoming 292 as a hi perf. dealer option lol they still occasionally still do it. thought i'd pass it on as this info might save someone some money down the road maybe.

[corvette6698512]

Hmm interesting. That would be a pretty neat mod. Might go see if the local junkyard has any 4.3's.

[292farmer]

yeah im hoping this helps out someone as the only other options are cliffords version which is 3000-4000$ or custom making one, either are good but some time we dont have the money or time. so decided to pass this on.

[gripnrip]

292 Farmer, thanks for the info, I have a 67 shorty that I'm going to upgrade with a 292 and hopefully a modern automatic with an overdrive. Is the 87 the only year of 4.3 that will work? I ask because I may be able to get an astro van that I believe has a 4.3 for a couple hundred bucks. Do you know what extra tuning is involved, also if you have any other info on the gm 6 cylinders and 292's in particular I'm all ears.
Thanks.

[suville]

I like this idea! Might be a way to get some better mileage out of a 292. On that note it might be worth postin over on Inliners.org and see what response is there, there is a huge amount of info over there on L6 engines.

[292farmer]

i know the 87 is a near perfect one as it uses the same dist/ignition system as the inline sixes after 87 they changed the ignition system to work better with the tbi. however im sure u can use any year of the 4.3 induction system and then find the parts in a junkyard of a 87 to make it work with your dizzy. i haven't done this yet, i plan on a dual carb setup. but my bosses mechanic told me this as an option and i decided to pass it on. as for additional tuning that would just consist of is perfecting the fuel curve. if your motors close to stock then stock 4.3 tune should be fine.
as for your tranny most of the people on this site say go with the 200-r4 as it has a better gear range for the inline 6, i cant say more as i'm a manual guy
as for more info on sixes get if u can get lou santuccis inline 6 power manual, im waiting for mine to show up soon cost me 25$ . im told its a great book. also check out these sites
http://cliffordperformance.net/
http://www.inliners.org/
http://stoveboltengineco.com/
what are u looking to do more power, fuel mileage, or combination? i'm no expert but my family in love with sixes so i've got some knowledge and ive learned some too, so just ask if i dont know the answer ill help look u for the answer.
yeah im hoping to post on inliners. soon and on stovebolt. to if i can

['68OrangeSunshine]

I thought the L-22 series L6s used a longer shaft distributor than the short-shaft V8/V6 distributors.
The TBI trick sounds good, although I'm still having fun with my 500 CFM Edelbrock 1404 AFB clone.

[Tx Firefighter]

The guy is wrong. A 4.3 distributor is no where near interchangeable with an inline 6. All you have to do is lay them next to each other to see the massive difference.

Total BS.

[Tx Firefighter]

4.3 distributor



inline 6 distributor



Notice the two units are completely different in lengths, configuration, oil pump drive tang, everything.

[292farmer]

after 87 yes as i said they wont interchange but in 87 when the 4.3 came out they shared a dist to keep the costs down im told of introducing the motor. and thats why 87 is a near direct changover

tx firefighter u may be right though as i said this was told to me by a mechanic who says he done it. and I havent done it yet. i was just hoping to pass this on with the hopes that it would help some people. even if the dist turn out to be different lengths im sure u can still connect the required hook ups with the right dist. and the tbi unit will mount up (make sure get all the wires and required pieces when u grab it) with an adapter. im just trying to pass on some info that willhopefully help someone. ill see if i can find some more info or talk to that mechanic today. it may be he said the style and hookups were the same on the dizzys,but ill talk to him today, if i made a mistake im sorry im just trying to help.

[PanelDeland]

Leo Santucci's book is a good guide on the 6 but most of the info has been posted here at one time or another.He goes into great depth on the 292 for racing but has some info on warmed over street engines.Just be prepared for sticker shock when you price performance parts for the 6,They are usually made of "UNOBTAINIUM".
That said I want to keep my 250 and the TBI has been in my thoughts though I have a "Offy" for it.Unfortunately the recommended carb is a Holley 390 and it seems to be made of said 'unobtainium" or close enough for us poor folks.

[292farmer]

ok i talked to the mechanic he said if u swap to a hei dist. for inline six then the hook ups will be the same, i miss understood when he said the distributors are the same, i thought he meant the whole thing not just the hook ups so yes the dist are different lengths but the rest will still hook up and work.
thank you tx firefighter for catching that as i didn't know that having never touched a 4.3 dizzy before.

['68OrangeSunshine]

The L6 HEI cap and the V6 HEI caps might be the same. The points caps are totally different.

[292farmer]

yes the points cap wont work , and im still trying to find out if theirs a difference from early hei dists and later ones.

[BLACK AND BLUE 67-72]

Another FYI is that the 4.3 came out in 85 not 87.

[292farmer]

my chilton and haynes manuals show 86 as earliest i thought maybe marketed as early 87. where else would i find start of production info? im curious to see what i can find on these motors.

[Tx Firefighter]

It's first year was 85

http://en.wikipedia.org/wiki/Chevrol...gree_V6_engine

Half way down the page...

[70STOVEBOLT]

Ok, who knows what all would be needed? Is the TBI electronically controlled, cable, or linkage? I am very interested in this setup. Also, where can you buy an adapter?

[292farmer]

ok it was 85 first out with either carb or throttle body but 87 was first year all started coming with throttle bodies and no carbs so i assume he said 87, so that u don't accidentally grab a carbed one which makes me wonder would that carb work good on a 292? i would think so..my mechanic said they had the machine shop in napa next door make them the adapter. but i believe its a two barrel setup. i believe i remember hearing the first ones were cable or linkage i think tx firefighter would know.

[Tx Firefighter]

TBI were cable throttle.

[70STOVEBOLT]

So I have a Pertronix Ignitor in my distributor, would I need to switch to an HEI?

[Tx Firefighter]

Yes, the TBI system uses a distributor very unlike an HEI.

[292farmer]

just thought id post this link to a chevy 235 with the 4.3l conversion, looks like an HEI dist?

http://www.youtube.com/watch?v=XxuSGXqGnf0