oxrabidus

I am in the beginning sage of a 4.3l Vortec V6 swap... it has the good (772 casting) heads... now do these heads flow as god as he V8 vortecs? i heard they are exactly the same minus one set of ports...but i am looking for a few thing that i cannot find...
-Do they make aluminum valve covers for this motor? (they are the centerbolt heads)
-i am also going to go with a carb setup, will a holley Carb fit on the edelbrock performer intake? or does GM or anyone make a better manifold?
-What is a good size carb? (I was thinking a Holley 4bbl 450cfm...)
-Can i use the stock fuel pump from a V8 carb camaro/firebird? How would i wire it up correctly?
-could i use the flywheel/clutch setup from a 305 or 350?
-what do you think would be a good size exhaust 2.5" or 3"? (i would think 3" considering its displacement but not sure because it is a V6...)
THANKS FOR THE INFO!

My goal is 320-350 hp (NA), we will see how far i can take it with a blower (one day...)... i have read of people doing it, but no one (or so i have yet to find out...) puts these into Camaros...
I may have more questions as i go along...and i will keep updating as i go along, for those ho are interested...

Irockz

iTrader: (1)

This is an interesting swap,but I think your going to be disappointed in the power level.If I were to do this swap I'd plant a bone stock CPI 4.3 in it and call it a day.A buddy of mine built up a similar 4.3 to what your proposing,custom grind roller cam,Edelbrock intake,holley,custom fabbed headers,the works.He had a fortune in that thing and it made 307 HP on the dyno.It was waste of money for the sake of being "different.He had it in an S10,and could have sneezed at a 350 and made that power for half the money.It is very uncommon for me to say this,but if your wanting 300+ HP,your pissing in the wind building a 4.3,go with a V8.

oxrabidus

you think so? i have heard its easy for them to get 300 horsepower with some porting and a good cam... which is all i was gonna do to it... and the carb stuff...

Irockz

iTrader: (1)

Your asking for roughly 1.25 hp/cubic inch.There really is no aftermarket for these things,the Edelbrock was the only intake available last I knew,and anything you buy that is unique to the 4.3 is going to cost double that of a smallblock.If you were making a daily driver and wanted something stouter that the 60* 6s that these cars came with,I'd say go for it.But from a performance standpoint,yes,you can throw enough money at the thing to make it run.But it won't be cost effective,and if you actually get past the 300hp mark,it won't be fuel efficiant,either.

Fast355

iTrader: (2)

Actually the 96+ 4.3 Vortec head flows identical to the L31 head. They share the same weak exhaust ports as the 350 heads. I would open the heads up in a heart beat and run 2.02/1.60" valves in them. GM Powertrain released Vortec 4.3s with spreadbore single plane manifolds on them for marine use. I would secure one and run a well tuned Q-Jet on it. Use a 1985 vacuum/mechanical advance distributer with a small block roller cam gear on it. The stock pistons should be trashed for a set of flat-top pistons, which will increase the compression ratio from 9.4 to 10.3:1 with the vortecs 64cc chambers. With a cam of around 208/208 @ .050 (thinking stock 1994 CPI 4.3 cam) in it, it should surprise many. A 350 of the same build would be about 415-425 HP. The 4.3 will make around 310-315 HP while maintaining good driveability and fuel mileage.

oxrabidus

well if i dont like it in the end then i could just throw in a v8... BUT... until then... if anyone could answer any of my questions i would appreciate it... edelbrock makes the only carb intake for it? will a holley bolt on to it?
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plus... all i an gonna do is a good port job on the heads and a good cam... the cams cost just as much as small block roller cams... and the pistons are the same as a 350... and if the heads flow as good as the v8 vortec heads (they should'.. i heard they were the exact same minus one set of ports) then getting 250 or so cfm should not be impossible and i THINK that may get me to 300 horses... and more with a blower...

robertfrank

iTrader: (27)

I've said it many times and I'll say it again. The only reason I would do a 4.3 in a camaro would be for a drift/autocross car project. hopped up 4.3 with a wc-t5 and 4.10 gears would be a perfect drift car/autocross car.

oxrabidus

would you happen to know if that is better than the edelbrock intake? and could i use the clutch and flywheel from a v8? and also i an not gonna have ac or power steering, does anyone make a non power steering box with a close ratio? and what about those total seal piston rings? are those worth any power or worth the money?

oxrabidus

also what effect do you think it would have if i change the firing order from 1-6-5-4-3-2 to 1-2-3-4-5-6? Good, bad, or pointless? and does GM still make this intake?

1991CamaroRslow

iTrader: (3)

I just built a 4.3 for my truck so I can tell you what I did. I had a set of L35 heads from a 1994 CPI Blazer (vin W). I found a Howards rebuilt cam on eBay for 20 bucks, it was the vin W cam that's 208 duration @ 50 and .444 lift as measured on my mic. Now here was the problem I ran into, I had a 1991 engine and it had no balance shaft, my cam was for the balance shaft engine. I ended up running into some issues with my stock engine and picked up a 1992 TBI engine for $200 and it had the balance shaft so I was good to use my cam. I also wouldn't have to deal with the annoying wobble you get from a non balance shaft 4.3 (yes I cared a bit about performance but I am willing to sacrifice some power to not have my hood look like the ocean at idle). I had my heads milled .030 cut the divider down in the stock TBI intake and called it a day.

Now to answer your questions, the Edelbrock intake is a good intake and will work very well with the stock vin W cam. Since your engine is a vortec it has the balance shaft in it already (look in the lifter valley, you'll know if it's there) so you can pick up a cheap camshaft if you know what you're looking for. The marine intake is a single plane design and will probably make a bit more top end but it's cast iron and you'll have to use the Qjet style flange carb or get an adapter. The Edelbrock intake will take a either style carb, Q jet or Holley flange. You can grind the teeth off the balance shaft gear and get away with it not turning but don't try and take it out, you'll have oil passages leaking. You can use a SBC flywheel/flexplate on a 4.3 so long as it has the same counter weight. You'll know pretty quick if you put the wrong one on it, it will shake horribly.

If I were doing a carb build up and money wasn't an option I would've had 2.02 1.60's cut in the set of 1996 Vortec heads I have as mentioned by Fast355, picked up one of the Edelbrock roller cams (they have several for these engines) and ran the Edelbrock performer intake with a 650cfm carb. I would've finished it off with shorty headers and a SINGLE (I CANT STRESS THAT ENOUGH) 3in exhaust. That would make for a pretty fun ride.

oxrabidus

how much of a weight difference is there between an iron and a aluminium intake you think? i heard the marine intake was worth 33 horsepower on a stock vortec motor... more with some porting...is a Q jet carb bad? how many cfm is it? and i read that the iron intake has a 4150 (i believe...) holley style flange... so you think 450 cfm would be to small?

oxrabidus

i am really curious about the firing order... what would happen if i change it to the 123456 order... and i saw a steel oil pan at summit would this happen to be any lighter than the stock one? because the stock one looks heavy as hell... and i read somewhere that you can plug the oil passages from the balance shaft... do you think taking it off will make a big enough difference in power to make it worthwhile? oh and how does your truck run now?

oxrabidus

i just found this borgeson steering box it says it is close ratio but it doesnt say the ratio... i saw another one and it was 20 to 1 ratio... that is not very tight... if anyone knows the ratio of this box i an really interested in manual steering... it is the borgeson 999001 box...

oxrabidus

how much more power do you think i would get from 5-6 inches of more vacuum? if any?

jhainer

For those of you who think the 4.3 isn't a good motor For HP I will let you know this stock it has 190 HP (2002 Xtreme Blazer 5 speed) I had one. Not a bad motor But while i had it I lived in Michigan and there is a company in Mt. Clemens Or clinton Twp not sure which since the borders of those two bounce back and forth. But check out Machperformance.com Bill Mach has an Xtreme that is turbo charged automatic and he is getting 23 MPG and ran 13.3 in the 1/4 Not bad for a little 6
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and what is really sad the 305 puts out less horse than the 6

Fast355

iTrader: (2)

Thats not entirely true. When you match up the year the engine was produced and the induction system used the 305 always had more power. The TBI 4.3 made 160 HP/235 TQ when it first came out. The 305 TBI made 170 HP/255 TQ. The 4.3 was eventually bumped to 175 HP/245 TQ in the Astro Van (1991-1992 B-vin code HO). About the same time the fullsize vans with the 305 got a roller cam and larger 3" exhaust from the 350s which pushed the output to 185 HP/265 TQ. Sure the CPI 4.3 would out perform the TBI 305, but the TPI 305 would out-perform the CPI. When the vortec series of engines came along in 96, the 305 would still out gun the 4.3. 230 HP vs. 190 HP.

oxrabidus

would anyone know about the firing order? the steering box? i am thinking about getting a stroker kit from speed o motive... but im not sure if its worth the ten cubes... and are the brodix v6 heads worth the price?

92camarorv6

3.4 550hp 5,000$ thats not bad so i thing you can do alot better with the 4.3 turbo it

oxrabidus

i thought about doing a twin turbo set up... but i am no welder and would not have the money and patience to attempt it... if anything i may just throw a procharger on it and make 500 hp at something like 10 pounds... a couple of people have done that...

oxrabidus

Well i took off the heads and three cylinders were filled, i mean FILLED with rust... the motor was seized up, and when we got it to turn we saw the the rust had eaten up the walls of two cylinders... needless to say...the motor was useless... well at least it was free...

G92RS

I used to have a show 94 s-10 with the 4.3 vortec in it... rebuilt the engine from the block up and i am here to say that if done correctly that v6 will lay waste to a stock 350 mine was pushing dual greddy twin turbos screaming about 600hp to the wheels... i couldnt start off in first or the front end of the truck would lift up due to the torque and the light weight of the s-10

stroker_SS

So you had a show truck with a drag style suspension?

G92RS

no it was lowered, im not saying i was getting funny car clearance on the front end but i did have problems steering it straight if i dropped the clutch in 1st

gregsz-28

iTrader: (1)

chvy

Hmm 4.3 talk...

Let me just say to the people who say the 4.3's aren't the best power build, that you are correct. There are a lot of other things better for the money.

Now let's talk forced induction. There is no engine cheaper and more readily available that can take boost like the 4.3. I'd welcome you to try. There are guys with s10's on stock internals that have been boosting 25psi on very good tunes for a long time.

Most people would call it quits from 16-18 psi, and thats really all you can run on the street without shitting your pants after you get sideways in 3rd gear at 65mph.

Supercharger kits from vortech for old s10s can be had for 1200$ in good condition off ebay. Include the cost of your engine and those parts and you're good to go. Throw on a 3-core intercooler and either SDS-EIC or a marine intake swap and you'll be coming up on tuning for 16 psi in no time.

18-20psi will net about 400hp, yes it can and has been done countless times on the 4.3. Small blocks can't take the amount of abuse that the little v6 can, check out some pictures of the mains and main cap spacing if youre a little confused as I was at one point in life with this concept. Also the vortec headed engines are the ones to get, they keep breathing all the way up to whatever boost you're taking in and raise the aweful stock redline about 1000rpms on boost. A lot of sy/ty guys swap to the vortec heads


... changing from one firing order to the other as someone suggested earlier is not a good idea at all. If you really want more than 500hp out of the block (about as much as the crank can take with splayed mains and forged internals), then start looking into a sy/ty block and ignition system it'll be cheaper in the long run.

jhainer

This came from the depths i posted that almost 2 years ago.
but your right year to year the 305 had more than the 4.3 but the most a third gen camaro had was 230hp in 5 speed 92 camaro's 215 in the auto's now you take into account the weight difference. they would even out. Now I'm not saying i would do one I am saying it wouldn't be a bad swap. and if you supercharge or turbo charge it it would be much nicer. and the parts to do that are somewhat cheaper. and I heard somewhere that it changes the weight dias in the camaro alittle more to the rear so the car handles better. I can't remember where i heard that tho.. But if i had thought it was something i would have liked to do I would have done it instead of doing the BBC swap in my 1986 my 305 put out 190hp same as my 4.3 did in my extreme blaser. I just saying it can be done cheaply for my 86 it would have been a viable swap option since it had the same hp ratings. and like said machperformance made some nice parts to make them fast and also fuel efficiant..

4playta

I got an *** load of money into a 4.3 build that I did for my wifes 2000 bravada, I drive it all the time myself so I wanted power. I was going to supercharge it but I would need to eliminate the AC and she wanted to keep the AC.

So naturally aspirated was the way I went. Cam, 2.02 1.60 valves, ported polished, marine intake, Custom MPFI setup because we wanted to keep the smarttrak that is controlled by the computer and it is already to install a rear mount turbo. N/A it dyno'd 312hp 344tq, that's with about $3000 in parts and another $2000 in machine work and dyno tuning.

I was in a catch 22 because this is a Bravada, if it was a S10 blazer or pickup or anything that did not have the AWD Smartrak I would have gone V8. The plus is when we get our taxes back I will be installing a STS turbo now and expect a minimum of 400hp and am trying for 450hp. With the MPFI I will be able to adjust everything with EFI Live.

What is really funny though is it looks bone stock on the outside and we are going to keep it that way. So rich kids who's daddy just bought them a new 5.0 beware of the little blonde chick that pulls up next to you at a red light in a cranberry colored Bravada called the Bravoon

PS: Moral to the story is you are not going to get 300hp out of your 4.3 without a fat wallet...don't think for a minute you can just throw a cam in some headers and a 4bl and you have 300hp...that will probable get you to 220-240hp at best.

For people that claim they have a 300hp 4.3 with these mods I want to see the dyno sheet!!!

PS: This is my build, I basically followed this to the T except for I have a custom grind cam, custom injection system and it was dyno tuned using efi live, hence why I am getting a little more power and torque compared to a carb version.
http://www.hotrod.com/techarticles/e...o_results.html

Horsehammerr

Can we continue this discussion ? How did things go with the STS on your 4.3 ? I ask because I'm leaning towards building a rear mount turbo system of my own. I'm going with an '02 S-10 Crewcab, 4x4, 4.3 Vortec, 4L60E automatic.