Injector Housing to Head Port Match Issue

[LGAFF]

Greg VanDeventer from Mercury Marine????

[KJL]

My bad is name is Mike Ebert.

I may consider it. Blending the head port to the intake would also eliminate the oil/fuel from collecting there working its way through the gasket.
I figure I would use a long scribe and mark the heads while the intake is still on the head.

[KJL]

I wonder what it cost to ship?

[A26B]

Originally Posted by KJL

My bad is name is Mike Ebert.

I may consider it. Blending the head port to the intake would also eliminate the oil/fuel from collecting there working its way through the gasket.
I figure I would use a long scribe and mark the heads while the intake is still on the head.

Reference: Jerry's Gaskets are port enlarged to 36.5mm and precision die cut to dimensions from original engine drawings, so they make an ideal template to work from. They retain the bifurcation between the primary & secondary ports for stock applications.

You would benefit in the long run by using a set of correct gaskets as a reference for both the injector housing and cylinder head ports to match them up. Then, you can use a new set of gaskets without having to trim to match. At this point, it's not known if the injector ports are correctly located. I have seen significant core shift in early housings. I wouldn't recommend matching your Dunn heads to a set of injector housing that are not ported correctly.

BTW, you also have Aaron Scott, South Georgia Corvettes, in Thomasville, GA. He is closer to you and very well versed in the LT5.

[Dynomite]

Originally Posted by A26B

I wouldn't recommend matching your Dunn heads to a set of injector housing that are not ported correctly.

Then there are the Crankcase Ventilation (CV) differences between 90' and 91'-95' Injector Housings as Jerry described
90' and 91'-95' Injector Housing Differences

For which a modification exists if you install a 91' IH on a 90' Head for example.
I do not think there is an issue installing 90' IH on later Head as you would only end up with CV double restrictions vice NO restrictions going the other way.

Kind of like trying to mix 90' Plenums with 91' and later Plenums which look/fit the same but have differences in Charcoal Canister Vacuum connections. The charcoal canister for 91' being located by gas tank and the charcoal canister for 90' located under drivers side head light

[We Gone]

Originally Posted by 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?

KJL,
Drove it up on Sunday nite, I got old Blue in 2002 also had a 1990 Black/Gray for many years. I only know of about 3-4 others in this area. We need to meet up sometime.

Steve

[Locobob]

I don't see anything really wrong here, just looks like a ported injector housing on top of an unported head. In my experience plenums, injector housings and heads all exhibit some degree of port "skew" from the factory. You'll pick up some power if you port match the top of the head ports to the injector housings but I don't see where what you have now is hurting anything.

[Kevin]

Originally Posted by 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?

dunno how close you are to aaron but check out http://www.southgeorgiacorvette.com/

[KJL]

I have attached a picture showing the top side of the FI housing. It appears they were Siamese ported. Is this typical? Also, the secondary ports line up perfectly with the heads. The primary ports on the FI housing seem to all be oversize and they all line up perfectly with the head port side that is adjacent to the secondary port. After I remove the FI housing I am sure I will learn more including why the mysterious oil leak.

The previous owner said the car dyno'd at 389 rwhp.

[Locobob]

What you have there is a partial siamese or figure 8 porting job. Typically you'll find this style on more aggressively modified engines i.e. 368's, strokers, it is probably not doing much extra given your engines relatively low state of tune - doesn't hurt anything though.