Injector Housing to Head Port Match Issue

[KJL]

While addressing an issue regarding injection housing fuel injector seals, Jerry, from Jerry's LT5 Gaskets and Parts pointed out the housing I was describing was not for my 95 ZR-1 but for an earlier model engine. After pulling the intake plenum i noticed a port miss match between the injector housing and the head. Didn't think much of at at the time but given this new information, I thought I would attach a photo that represents the issue. Some ports are a bit better but this was one of the worse cases. Please note that the housing was ported by the previous owner who decided to use a non-stock housing and intake plenum for porting and powder coating. Unfortunately he no longer has the original parts. I guess my question is, is this common, if not, what can be done to fix it or at least improve it?

[XfireZ51]

A. Not unusual

B. you port match the head

[We Gone]

Nice to see another GA ZR-1.....We are few.

[LGAFF]

The mismatch while not ideal is not horrible, there is still a signficant improvement in flow without port matching. Porting matching can be done on the car.

**Use the gaskets to mark the area that needs to be removed

1)Tape off all of the intake ports you are not porting; and cover the motor to catch the aluminum. If you have secondaries only do the primary ports

2)buy tack clotch to put in the primary ports or spray some lint free cloth with WD40 to make it sticky to trap aluminum, push them into the ports. These are the back up layers

3)Put something on top of the cloth as a primary catch for the aluminum....cork, rubber stopper, or I used styrofoam balls from a craft store, cutting them in 1/2 and pushing them into the port on top of the cloth.......then soaking them in WD40, the styro is porous and caught alot of the aluminum splinters. IF using stoppers make sure you have a method of getting them out

4)Have a vacuum handy, stop periodically to vac out the splinters to reduce the mess...be careful not to suck out all of your cloths and stoppers, keep a finder on top of the stopper

5)Using the die grinder slowly start removing material, be sure to follow the angle of the port and not just going straight down

6)You only needs to go in an inch or slightly less to reap the "potential" 5-10hp, others have gone deeper.

[KJL]

To be clear, you are saying to remove material from the head to match the larger injector plenum port? Are there coolant passages in that area? I just am not sure I want to grind on a set of Dunn heads. I have done my fair share of porting intake ports but never a head port.

[LGAFF]

Correct, you are grinding on the heads, if you do not wish to do so, leave it.....it is not "hurting" you results vs stock. I did a set for a member and he did not port match it and still picked up 37rwhp

[LGAFF]

Who ported the intake?

[KJL]

How did you get your car to Marc's? That would be a cool thing to do but the logistics of it would be a challenge. Too bad there is no one in the Atlanta area. How long have you had the car?

[LGAFF]

I believe he shipped it

[KJL]

Not sure who ported it. Was ported by previous owner by some guy named Gregg.