engine install - headers on or off?

[Gwamp]

Should I put them on before I stuff the motor in or position them in the engine bay prior to dropping it in? What have you all done?

[PlasticBoob]

It was MUCH easier to get my engine in with the headers on, although as you can see from the pic, the flexplate would have been a good idea. ;)
http://home.off-road.com/~plasticboob/16.jpg

[Johnny Eskimo]

i had the shop install mine, because i had to have the whole exhaust replaced as well. cost me an arm and a leg because they wouldnt "overlook" installing cats.

the mech also mentioned that the drivers side comes kinda close to the brake proportioning valve. anyone come to find this a problem?

[Merc69]

I installed the headers after the install. Pretty easy. I used the Headman headers and they don't seem to come close to the proportioning valve.

Rob that's ok about the flex plate I forgot the reinforcement ring during the first engine install and then during this last install I forgot the dust plate after installing the motor. What a pain.

[andy d]

i just put my engine in with the stock ex manifolds. reading the chitlins manual suggested to remove the vapor canister and the heater core. this does give you more room and prevents crushing them. i also didnt put the waterpump pulley studs on. when my re-man was 1st installed by a local jeep dlr, they left the maniflds hanging on the y-pipe and then bolted them on once the engine was in. the stress this put on the y-pipe shortened its life considerably

[Heavyjp]

I am putting in Hedman Hedders as we speak and I can honestly tell you that We pounded in the drivers side. We went from the bottom up and mine is close to, I mean ON the frame and proportioning valve. I know that if we had taken the power steering pump loose then it would have went in, but my caveman friend had to do it his way. The passenger side went in with no trouble from underneath. We also threw the collector gasket flanges and reducers on so that my exhaust guy will have less to do. I'm driving it there on Tuesday and will have fun with the open headers.LOL
One thing that concerned me was the Flange plates were warped. We threw em in the benchvise and crimped em. I gotta get my man to check just to make sure I won't have leakage...

[RoofPrints]

I was at Klanks today as he prepared to swap engines. His 401 has headers, and doesn't look like it will have any clearance issues pulling the motor with them on. It seems like it would much easier if you could drop it in with them on, rather than squeezing your hand in to fasten them later. However, I don't know what differences there are in engine compartments between his '89 GW and your old-timer.
Are you that close to putting it in?

Jim
-----------------------

stock '87 GW w/factory vinyl top & power moonroof
stock '89 GW w/bad motor and stylin' headliner
'96 Suburban 2500 LT 7.4L w/roof-mounted gun rack

“If it ain’t broke, you’re not trying!”
Red Green

[kjax]

I installed without headers on. Would do it with factory manifolds, but not full headers.

Drivers side header (hedman) fit like a dream. No issue with brake proportioning valve. The passenger side was a bear, though, with the heater box in place. If I had it to do again, I would take that out. Did slip up from the bottom, but trans lines are hitting. Did not slip up as easy as I would like, and that last bolt on the header is a pain, if you ask me.

I think the thing to do with the flange is to grind smooth and weld as necessary to ensure pipe is attatched (and regrind smooth), in order to avoid leaks. I didn't do this, and I'm thinking of taking mine back out. Anyone else have an issue with hedman leaking after install? (constant problem)

They didn't do a very good job of grinding the weld around the port or getting the flange smooth, IMO.

[Gwamp]

Originally posted by RoofPrints:
I was at Klanks today as he prepared to swap engines. His 401 has headers, and doesn't look like it will have any clearance issues pulling the motor with them on. It seems like it would much easier if you could drop it in with them on, rather than squeezing your hand in to fasten them later. However, I don't know what differences there are in engine compartments between his '89 GW and your old-timer.
Are you that close to putting it in?
I wish I was that close! I am just thinking ahead. From the looks of things, I am 1-2 weeks out to install it. I think I am going to install the headers inside and then drop the motor in. I have plenty of room in there as I have 0 stuff in the compartment except for the heater core box.

[Shake N Bake]

Call me crazy, but when an engine goes in - or comes out. I like it to be pretty bare. The risk of beating stuff up is too great. Putting on factory headers while the engine is in isn't a huge headache.

LOL - Forgetting a flex plate? nah thats not a big deal. When we put the engine into my 79, I got everything installed, and did a final inspection (of shop and engine) to make sure everything was right. Found the oil slinger sitting on top of the old timing chain. OOPS. Needless to say there was much cursing and swearing - and a few new seals purchased.

[Gwamp]

These are aftermarket headers of unknown brand (probably Hedman).

[seadog]

Same here I like it to be pretty bare and I have hedman headers.It wasn't all that much to install em once the motor was in place.They clear everything good on my 78 chief,but run real close to the starter so I wrapped em and the starter.

[billyrb]

set the headers in first, then lower the engine in. This way, you don't have to pound them in, but you also don't run the risk of breaking your heater box (like I did).

[PlasticBoob]

Guys, guys, you can't beat me - shortly after we put the flexplate back on, we realized that the dowels were broken - it wouldn't go into the tranny! :mad: Turns out my dad "accidentally" lowered the engine while it was on a cheapy stand and it tilted a little low (some bolts were in the dowel pins) So we went all the way back to the engine shop, because we couldn't get them out ourselves! :mad: :mad: Someone should start a thread - the dumbest things we've done to our poor engines. LOL! smile.gif