[83GT]

Hi guys-

I have an '83 GT (hence the name) with a nicely prepped 302 residing in it. The block is from 1980. I recently bought some new heads for it, the old style 302 BOSS heads thinking that these are superior to factory smog heads, which I'm sure they are. Only one problem.. I just looked at the coolant passages on the head (you know, the little eyebrow shaped ones) and my block does not have these same passages. Did I make a major boo-boo by spending lots of money for the heads, porting out the exhaust ports and gasket matching the intake SO THEY WON'T FIT MY MOTOR? Just wonderin if anyone had any input to see if these heads WILL work on my block or not. Thanks!

[GTRaptor]

I beleive thats not the only problem you will need to match the heads to a boss manifold and will need to modify a set of headers, i dont think the bolt spacing is the same as regular 5.0 heads.

Besides, the Boss heads were high RPM heads, working best at around7k rpms, the large valves will kill your low end torque big time.

You will do better with more modern heads, even Cobra or GT40p iron heads.

[83GT]

I think I mis-classified my new heads as BOSS heads. I really doubt that they are. They have 1.78"/1.45" valves, I'm sure the BOSSes didn't use them. I just listened to a guy that runs a machine shop up here and he told me that these "late 60's" heads that I have won't work because the coolant passsages won't line up.

I have also done a mock installation and my Edelbrock Victor Jr. Intake matches up to these heads just fine. So do my headers. I think I was just misinformed. BUT, what do I do about the eyebrow shaped soolant passages not lining up to my block? Tap into the block to get coolant circulation? Are these eyebrow shaped passages really coolant passages?? Casting # on the head is D20E.

[83GT]

OKay okay I learned a ton today. I'm mildly retarded I think. The weird eyebrow shaped passages are steam holes. All I gotta do is tap into the block using the head gasket as a template. I freaked out over nothing...maybe just because I'm SOOOO CLOSE to putting my baby back together, this time with 50 more horses under that nasty cowl hood..

Do you guys think the following is a good combo? I've got a 306, ported D20E (58cc chamber) heads with Crane 7/16 roller rockers, a Wolverine cam at 224/236, bored .040 over with TRW forged dished pistons, full MSD 6-AL ignition, Holley high-flow fuel pump, Edelbrock Victor Jr. Intake, and Edelbrock 650 carb. I have a 5 speed (T5) with 4.10 gears in the back. I've got full length headers dumping into Flowmasters out the back. I hope to run low 13's/high 12's with this combo. Achievable?

[Monkey Boy]

I don't know how much porting you did on the heads but I would say you might have too much cam for the heads and definitley too much intake. Again, I don't know how much head porting you did or what your flow numbers are so I could be dead wrong.

[Mike Kievit]

I am not qualified to answer your question, but in the Ford Racing Performance Parts catalog. The suggested recommendations for drilling the head or block, and installing plugs in the head is discussed. They even have drawings.

Do a little more research to confirm the parts you have, and what block you have.

Good luck,

MK

[83GT]

Thanks for the input guys. I have put my motor back together using the D20E 58cc heads. (The heads have been milled down a few thousandths to produce a 56.2 cc chamber) I found out that these heads are used on the '71-74 302's. the top end rebuild went great- I ended up drilling 8 small holes in the block to line up cooling passages to the heads (steam ports). This is the first set of heads I have ever ported, and I used a digital micrometer to match the port sizes within .005" of each other.

I started her up and about wet my seat. Scary. Going from '88 smogger stock heads to the D20E castings was a great idea. I don't have an actual horsepower output increase but I would estimate it at 40 more than I had before..and I spent $280 for both heads, already rebuilt. Ported them myself and saved a bunch of money! Pretty cheap upgrade that I would suggest to those who are also budget conscious.

[crazycarnut]

wow that is pretty cheap. glad you liked it.