98 4.3w off road engine being built !! Suggestions?
 

OK so I. Rebuilding my engine and it's for my trail truck.
I tried saving my egr pipe but it broke so I'm going full off road now. What all do I have to do and how do I do it guys? It's my intention to delete all emissions at this point ! Yes I realized will have to be reprogrammed.

Nothing guys...? I've been searching everyday and I've found a few things including a possible way to make my rockers adjustable like the old small blocks so I can buy a bigger camshaft.
Has anybody done this. I was told it was a matter of removing my rocker arm studs AMD installing new ones that would except the old small block lock nuts.sounds simple and affordable.

Your post starts off by stating you are building an offroad truck and asks "what do I do and how to I do it". Those are very BROAD questions that seems to suggest that you have no clear direction and often leads to people reading your post and moving on. Lay out your intentions (put together a specific path to your desired endgame), ask specific questions, and you may find that you get answers. If you don't put time into your build, you shouldn't be surprised to find that no one else is willing to do it for you.

As far as the rocker arms are concerned, in the past the heads had to be drilled and tapped to fit the older rocker studs. It was the difference between the new metric bolt and the older SAE stud. I'm not sure what is available now for these engines, but a quick call to one of the major cam manufacturers would likely get you that information.

Well to be honest I had no clear direction on my engine plans because I'm trying to keep it affordable. So I figured I'd ask for some suggestions .

Cam company's may make the cam, that doesn't mean they have the studio conversion I need, the cam I'm looking at doesn't have adjustable rockers available but it's required.
So ask the guys who deal with our specific engines I figured.

Looking into this a bit more (Google finds an amazing amount of information), it would appear that your '98 engine may have screw in studs with stamped steel rockers, just ones with a shoulder on them for the net lash valvetrain setup used from the factory. It wasn't until 1999 or 2000 where the rockers were changed to bolt down with the use of a rocker arm support.

Summit Racing has THESE ARP STUDS that state they are for Vortec 4.3L engines. Maybe you can call ARP to confirm? Or Summit? Cam manufacturers will also likely have answers to this very question. Just because they only sell the cam doesn't mean they don't know specifics about the engine that it goes into and what other supporting mods are required to run said cam. They wouldn't be very good at manufacturing cams if they didn't know the limitations of each application and how to make the appropriate changes, if required.

One thing to watch out for is valve cover clearance. Changing rocker arms could cause an interference between the rocker arm and the valve cover. I'm not sure what your options may be for aftermarket valve covers that would add clearance in this area. In the past, where aftermarket alternatives were lacking, I have seen people machine spacers out of aluminum to move the valve cover up and out of the way of the rocker arm. That's $$$ though.

Having no clear direction and asking specific questions to gain direction is one thing. Asking vague questions and relying on others to do the research for you is another. Google is your friend, use it. If you find conflicting information, ask away and we'll see what we can do to get you the facts. Keep on the path you're on and you'll find yourself complaining even more about the lack of responses. I'm trying to help you get responses. Show effort and it may result in more people answering up.

Thanks for your help. It's not that I don't use Google or your search engine. Maybe I give to much information for it or wrong terms but I find nothing on building theses engines. I actually called summit before I ever made a single post AMD they said it had to have new rocker arms.

Adding all my cost just to get a mild difference it just doesn't make sense to do an engine build at all for performance so I made the decision I don't want that much money in this particular truck.
So I'm decking the heads to raise compression and I'm goi g to bore the cylinders out. Only question let is how far can I punch the cylinders to get a safe and good running truck for internal modifications.
I still have to find a pair of headers as well. Intake wise I'm still not sure. I wish I had the cash to just throw an LS1 in it but that ends up with a pike of ****.

I'm sorry if it seems as though I'm looking for others to do my home work but I figure there's got to be a ton of people who've done or wanted more power then this engine produces so just ask the guys who've done it already and get a your wasting your time and buy a small block or something.

Call comp cam, tell them what you want. I did and they gave me the part numbers for a cam and said I would need new springs. Told them i didnt want to do any head work and thats what they set me up with. So Cam, get some headers and high flow exhaust, then have send your computer out to be reprogrammed. You should gain 30 -40 more horsepower and a bunch more torque. Torque is really what you want. Theres a start for ya

Well I've already had the machine shop assemble the head. I did have to call for headers to . Summit told me the same basic thing NA except the big dollar ones. I'm still trying to decide what brand headers to buy . Pacesetter or some EBay units that look identical except there stainless steel. Any thoughts on that.?

I got mine,front amazon, been a year and they're fine

What brand are they and did you feel they made a difference in the vehicle at all?

these are the ones I got. Did feel there was some difference after install. Then after finishing all my mods to the engine and the number 1 biggest change was when I han the computer flashed. best thing you can do for improvment. https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

deleted - photo wouldn't post

Ok guys I'm in the process of bolting my rockers on soon as I post this.
My off road engine build is going nicely as I was given a Carb today for the 4.3 marine and he said its a 500cfm nice 2 barrel. I had one on my Full size and the truck would run with the old fox body Mustangs.
So I've been searching for info on a carb conversion for our trucks and I havent located a thinng where anybody mentions gutting the whole ECU. I've found plenty of info to keep my 4l60E but I want it gone!!! I want the ECU GONE!!!!!!!!! So can I do this and keep my push button 4x4? maybe keep air bags is all I care to keep. AIR BAGS is a optional and I should probably get rid of them for off road I suppose.

So what do I have to do to delete my ECU and its harness? I'm actually considering ordering a wiring harness for an old HEI truck and be done with it.
My trans plans are 4l60 or 700r4

Again thanks for the help and I have looked for this but all the threads Ive read the keep the ecu in truck.

Anything guys??

alittle upon install ,but as stated above, get the computer flashed

I don't want the computer that's what I'm trying to eliminate

I have a carb and a hei distributor all I need is to figure out how to make the 4l60 or 700r4 work with lockup and the pushbutton 4X4. I want to gut the whole ECU

As long as you don't care what no longer works in the truck and/or are willing to rewire those things that you do care about, rip it all out and see what you have to do to get things working again. Just be warned that your dash will no longer work without the ECM along with many other systems in the truck. But hey, it's an offroad only truck right...

You may want to invest in a quality manual that has wiring diagrams and start doing your own homework.

Quite frankly, you seem overwhelmed with the basic stuff. You probably should have started with something older with less electronic integration.

Lol Not overwhelmed in the least, as much as I love my Blazer,, Gm electrical is as reliable as a cracked out prostitute.

I'm amazed at how nobody on this forum is willing to talk about emissions delete and how if it's brought up your thread is locked!!!
Land of the free though right sheep!

what year is this blazer?

Discussion of bypassing emissions for on-road vehicles is discouraged as defeating emissions equipment is illegal on the federal level in the US. Off-road vehicles do not yet fall into this category and discussions have occurred in detail, but please keep up with the ignorant insults. Lets see where that gets you. :icon_deadhorse:

GM electronics aren't reliable...? This forum supports active discussions on vehicles that are, in most cases, over 20 years old. The vast majority of the problems are component failures, not electrical. And even at that, most electrical problems are due to either improper repairs in the past or were the result of damage caused by another failure. Do you know how many s-series trucks are out there? Unreliable...hardly.

Why bring up emissions delete anyway other than to go on a little rant to try to get back at the forum for some reason? Like it owes you something...

Is it the emissions equipment that bothers you most about your truck? Would removing it from your off-road build, leaving the rest of the electronically controlled equipment be satisfactory to you? If so, it would be much easier to cut it all off behind the upstream O2 sensors and keep the ECM (after a reprogram to remove those trouble codes affected by the cat, downstream O2 sensor, AIR pump, and EGR delete) than it is to completely remove the ECM from the truck. Keeping the ECM will allow you to keep the injection system, ignition system, dash, transmission, and all of the other systems in the truck that are tied into the ECM/BCM system.

Quick update as it’s been a few years guys. I’m finally getting back to my build. SS brake lines from inline tube have been installed the rear ZR2 axle bolted in last night and I’m in the middle of the polyurethane body bushings and 1/2” body lift. She is not as clean as she looked before a pressure wash I’ll say that. Here’s a pic though of current situation.
https://cimg8.ibsrv.net/gimg/blazerf...9259b9aea.jpeg
Current condition

Nice to see it still alive and kicking.