1LE OWNER

I am going to be putting a brand new rebuilt tpi 350 with around 400 + hp and more torque. Will it be easier to put the headers on and then put the motor in the car? Or is that not possible? Also With that much power is there a catback system good enough to accomodate my needs? Will I need to get some kinda duals put on. My uncle owns an exhaust and brake shop so I can have duals put on and I live in KS there is no smog test or whatever. But I do like the MAC catback system it looks really nice. If I were to get that would it be best to get the MAC headers or are there better ones for the amount of HP I will be putting out? Also Within about 6 months of putting in the engine I may have an ATI Procharger installed. IF I do will need to consider that when I do my exhaust.

Mark A Shields

I'd put the headers on first. I'd also go with dual exhaust since emissions aren't a problem.

eighty2z28

I put my headers on before I put my motor back in, I ended up having to remove the right one to fit the engine in, then I had to put it back on and it was a pain with it in the car, I recommend putting the left one on, then put the motor in, befor you put the motor mount bolts in, lift the right side as much as you can While beeing able to hold the header in place ( have a friend help ya), then bolt the right one on,,,,,, you might not have much clearance, but its better than finding out to late

pontiacZ28

I agree, but you shouldn't put them on before dropping the engine in b/c you might ding or damage them. Put the headers on the X-Member drop in the engine and then bolt them on. If you really have a 1LE than the passenger side (NO AC) would be no problem anyways. So you could just put the drivers side on the X-Member. Also you can't run "true duals" on a thirdgen so you might as well go with a bigger single pipe plus it will scavenge better than duals.

3rdgen327

well it is according to if you are going to get the large tube headers or small tubes, also are you getting full lenght headers or shorties? i have 1 3/4" primary tube headers 3" collectors full lenght hooker super comp's. i tried to put the headers on then drop the motor in nogo. i had to remover the headers. the directions from hooker.
raise car 36 inches in the air then lift motor one side at a time 3 inches or so and put header in from the bottom. it was a time putting them in. i have a third gen, my buddy has a 4th gen. it was just as big a pain as mine was and his 99 ls1 i helped remove them.pain also all 3 of them had to be off the ground to accoplish the task

88Bravo

Super comp tip, when going to install the pass side, take the air tubes and bend them in some. This will help fit around everything. You will scrap them up some but they will fit. Install from the bottom.

As for you 1LE, I would set the headers in the engine comp drop in the motorand install the headers before putting in the motor mounts. THis might give you alittle more room since you can sway the motor. You might want to look into installing the plugs around this time. And try not to paint around the inside of the flange that bolts to the head. I have heard when you try to change gaskets they can stick to the headers. Has that happen to anybody here??

GTA91

iTrader: (1)

Thanks guys for all these tips! I had TES's on my 305 but we pulled that motor tonight. A hotcammed L98 is going in with longtubes on it. Guess I'll do the " lay headers in frame- drop motor in-bolt them on-bolt motor in-method" LOL Thanks again!

3rdgen327

hey post back here and let us know how it goes...........