Hello,
I have an 86 IRoc that I am trying to put a 383 into. The problem is the headers and or the Y pipe dont line up correctly. The driver side header puts the flange about 1/2'' from the K member. The passenger side shoots the flange straight down so when I try to bolt up the Y pipe it is down at an angle. At first I was using a set of headers that came with the buy, which I assume are Flowtech. Then I purchased the Flowtech Y pipe and ran into this issue. I then bought a set of Flowtech headers that matched the Y pipe to be certain. (Pretty much the same issue, except the passenger side is fine now.)

I am trying to use headers 11102FLT and Y pipe 11102YFLT.
The heads I am using are from Skip White Performance. Part # A64210583.

Anyone have any idea how to solve this problem?

 

Sounds like time to get the hammer out, idk haha? But I bought some summit headers from my cousin and later bought a ypipe from flowtech(flowtech supposedly manufactures the summit pieces) and I had to pry it a ton to get it to fit. Also my ypipe touches my oil pan, so I am going to have to modify it or take it to the shop. :/

 

I think were going to go with modifying the fire wall and moving the engine back about an inch and a half. XD wish us luck.

 

NOOOO....just heat up the pipes and bend em. seriously dont hack the firewall

 

We pretty much figured out that the problem is the heads. The exhaust ports are moved about 1/2'' forward. Therefore the headers are too far forward and entirely in the wrong place. I called HawksThirdGen and they said they know this problem exists with big heads like I have. They said the only solution is a set of $900 headers. Also I wont be able to use my cross member for the TH350 anymore with the $900 headers.

Honestly putting this 383 into the Camaro has been by far the most unnecessarily hard project ever. NOTHING wants to be correct on this car, I think its cursed.

Seriously guys, I cant be the first person to try to put a 383 with big heads into a 3rd gen. I have searched thru the forums and cant find anyone who has solved, let alone ran into this problem.

 

I would try to fix the exhaust first, easier job too. If you have to spend a few hundred for a shop to fix it up.

 

What heads do you have that the exhaust isnt in the factory location? I know some have slightly raised exhaust ports.... but a half inch forward is really odd.

 

taken from skip whites site under specs for above mentioned heads:
Comb Chambers: 64cc, 58cc also available and 68cc fully cnc d

Intake Valve Dia: 2.02”

Intake Port volume: 210cc

Intake Port Dim: 2.247” x 1.218”

Int Port Location: Stock

Intake Gasket: Fel-Pro# 1206, Some intakes require a Fel Pro 1266 intake gasket, or 1255 if using Vortec intake.

Exh Valve Dia.: 1.600”

Exh Port volume: 70cc

Exhaust Port Dim: 1.356” x 1.420” w

Exh Port Location: Stock location & bolt pattern

Exhaust Gasket: Fel-Pro# 1405

Flow, Intake: 264cfm @ .700” lift / 28”

Flow, Exhaust: 152cfm @ .700” lift / 28”

Head Bolts: Must use extended reach with true head bolt washers or head studs. See our other listings for accessories

Are you bolting both headers on loose then attempting to bolt the y-pipe up? If it's still not workin out why not just have a custom exhaust shop custom fab a y-pipe for u?

 

So, did you get the wrong headers?

 

Sooo what your saying is the pass side exhaust ports are 1/2" farther forward that they should be????
If thats the case then the DR side should be 1/2" towards the rear..
This problem makes NO sense to me at all..
Can you post some pix and measurements??

I have a 4++ ci SBC with AFR 235s in my car and there is no problems at all.

 

I had issues with the same headers and y pipe with a set of production double humps, sure they are cheap but you get what you pay for. Very poor selection for a large cube engine to breath out of, small tubes, poor welds, internal restrictions within the primaries are common etc. At first I bolted em on and tried to align the y-pipe with no luck, only got it bolted on with everything simply installed with the bolts a half inch from the flange surface. Also I had to switch to a LT1 starter from a stocker because of the pass side header was too tight against the starter so much so that the solenoid snapped off...

 

Posted the related specs for his heads above while state the ports are in stock location with same bolt pattern, the issue is the headers.

 

Ok here is where I sit. With the old set of headers bolted to another engine on a stand, the Y pipe will not bolt up. With the new headers bolted to stand engine, Y pipe is a perfect fit. Putting the other engine in the car for now till I can work out the bugs.

The driver side exhaust ports are 1/2'' forward, passenger side 1/2'' back. Measuring from head bolt to center of port on my heads, and the stock heads, there is a 1/2'' difference. There is no argument that the bigger heads are not off. I found someone else on here who has solved the problem, just requires a set of full size flat collector headers. Ill post pics once I get them and keep you all posted in case anyone else has a related issue.

Who knew the difference between 400 and 500+ hp was such a pain -_-

 

n/m

 

I find it very hard to believe that those heads have the exhaust ports in the wrong location. That basically means that the exhaust valve isnt lined up with the cylinder bore. A half inch is a pretty big discrepancy.

I am tempted to say your heads are just... made wrong. They're Chinese pro comp heads... they're meant to be bolt-on compatible with pretty much everything. Exhaust port location is pretty standardized aside from some heads that have ports slightly taller than factory heads but even that isn't a hugely big deal.