E5 heads on 87 h.o. went 13.7 in 1/4 mile

[saleen9973]

Hey guys i just bought a 1987 gt. Mods are under drive pullies, bbk shorties, off road h-pipe, 2 chamber flows, 3.73's, aluminum driveshaft, stock t-5 with steda tri ax, lakewood 50/50's, lakewood 70/30's, eibach drag lainch kit with airbag, no front sway bar, the motor is a 87 stock bottom end with unported E5 heads, 70mm throttle body, cai, electric fan. The guy i bought it from claims it went 13.7 at 99 mph on bfg drag radials. is this possible with the E5 heads? I mean the car pulls like a mother up intill about 5200-5400 rpm I know that E7's pull longer than that. I just got a set of E7's for free but they were left in the rain and are rusty, I have a sand blaster and could clean the up and then send them off to the machine shop to be redone if that will net me lower times.

 

[85_SS_302_Coupe]

The 5's and 7's are nearly identical (an absolute waste of time and money to switch from 5's to 7s if they're both bone stock)....so with the mods you're mentioned a 13.7 wouldn't be out of the question for either set of heads.

 

[saleen9973]

O.k i just heard that the E7 heads had a small cc than the E5 heads so in turn it would raise the compression and maybe give me a few hp?

 

[85_SS_302_Coupe]

O.k i just heard that the E7 heads had a small cc than the E5 heads so in turn it would raise the compression and maybe give me a few hp?

Yeah....that's really the only difference that i recall....the 85's clock in at 8.4:1 and the '87+ is something like 9:1 i think, so yeah you'd pick up a tad, but i don't know if it's enough that you'd even notice it. Factory ratings on the two engines are only 10hp apart. I actually just put some E7's on my car earlier this year but only because they had a decent gasket matched port job and were newer with less miles than my E5's, and i had a blown head gasket anyways. If for some reason you're planning on having the heads off, or if you just plain don't care to do the work, sure why not?

 

[saleen9973]

Did you notice any difference between the E5's and the E7's in performance?

 

[85_SS_302_Coupe]

Did you notice any difference between the E5's and the E7's in performance?

Well, i got the heads from a friend who picked up 11hp on the dyno from the gasket match port job, but even that isn't enough to really feel it. The car definitely ran a lot better but that mainly has to do with my car and how it was set up before hand. For example, the emissions cross over pipe that connects to the back of the heads....my car had that pipe on it for the longest time and i came to find out that it had rusted and was open at each end...so it was basically like a huge exhaust leak at the back of each head! That plus the fact that my engine has an obscene amount of miles on it (250k+) meant that the valve guides in the E5s were shot and it burned oil through those pretty badly...so yeah overall i really noticed a big difference but i haven't had it back to the track yet.


Personally if it were me and i were in your shoes, i'd wait until i was going to do something like a cam swap or something, some kind of excuse to go deeper into the engine, like if you already have all the intake off anyways....that sort of thing. Otherwise to me personally it just wouldn't be worth the time and effort and even the price of head gaskets to do all that work.

Although, the gasket match job he did was very basic....just put your gaskets on the intake/exhaust ports, trace along the head with a marker and get out the grinding bits and go to work....he did it all himself and it was a very basic job ( i really use the term "ported" very loosely because it's really just gasket matching). So, maybe if you wanna clean up the E7s, then swap them out...

 

[saleen9973]

I planned on porting these my self i have a die grinder and carbide bits. I am gonna go by the diy e7 porting i found on the web. a little bowl work and open up the ports. but that is a winter project.

 

[Dean85GT]

I went 13.1 at 104 with my E5 heads...and believe me there actually is a big difference between the E5s and E7s. On my E5s I couldnt even fit my finger into the exhaust port.

 

[85_SS_302_Coupe]

I went 13.1 at 104 with my E5 heads...and believe me there actually is a big difference between the E5s and E7s. On my E5s I couldnt even fit my finger into the exhaust port.

That's strange.....when we swapped out the 5s for 7s on mine, even with the gasket match job they were almost identical....we even got one mixed up and almost put an E5 back on....maybe someone did some porting on mine somewhere along the line and i didn't notice. Either that or you have huge sausage fingers

 

[Dean85GT]

no sausage fingers here!

 

[NOmoreHONDA]

The e7's work awesome on 86 shortblocks. It brings compression up substantially. My buddy built an 86 short block with e7 heads with completely stock internals using all autozone brand rings, bearings, etc. (total cost was about 80.00. That thing is an animal. That combo probably nets a good 10-10.5.1 compression or more!

 

[85_SS_302_Coupe]

The e7's work awesome on 86 shortblocks. It brings compression up substantially. My buddy built an 86 short block with e7 heads with completely stock internals using all autozone brand rings, bearings, etc. (total cost was about 80.00. That thing is an animal. That combo probably nets a good 10-10.5.1 compression or more!

Yeah but you're limited to cam lift and duration unless you notch the pistons, which will take that compression away.