did upgrades and power is just ok

[mercurycapri]

my 86 5.0 I did some mods to it and it doesn't seem to be any quicker than a stock mustang. unless I put it to the floor and push on the throttle hard onto the floor then it takes off pretty good. Here is what ive done
86 stock short block flat top pistons with 1978 rebuilt heads more for the extra compression ratio. Solid motor mounts BBk shorty headers 1 5/8 gutted H pipe 2 1/4 flowmaster cat back. Edelbrock performer intake and edelbrock 600 cfm carburetor. Electric cooling fan and eliminated the smog pump and AC unit. Stock manual trans and rear diff. Im just confused why the car isn't faster than a stock mustang the coil is good new tune up good fuel pressure and new fuel filter. Could the distributer be bad? Could I have not adjusted the carburetor right? Timing chain is brand new

 

[mercurycapri]

sorry its in my 86 capri I took the fuel injected stuff off

 

[EMW150]

What is the total timing set at? Is it a stock cam?

 

[mercurycapri]

its stock camshaft and I put the timing at 11

 

[fastranger347]

the heads are your problem,you picked a head that was created during a smog crises and gas crunch, they have no flow, no port size and only emmisions in mind no matter howmuch porting you do to those heads youll be better off with e7te castings (87 and up) if you wanto stick with a factory head

 

[mercurycapri]

I would have bought E7 but these where a killer deal and I needed my car to run. I was kinda low on cash at the time that's why I bought those but these heads should be heck allot better than the E6 that was on it. It was very quick when i first took it for a spin but seemed to slow down a bit or maybe im just used to it now

 

[stangjunkie]

I would have bought E7 but these where a killer deal and I needed my car to run. I was kinda low on cash at the time that's why I bought those but these heads should be heck allot better than the E6 that was on it. It was very quick when i first took it for a spin but seemed to slow down a bit or maybe im just used to it now

i have 3-4 pairs of stock heads from fox mustang if your intersted lemme know... they don't do me any good

 

[rd]

I went down that road exactly with my 79. Put a rebuilt shortblock in about 87, with stock replacement pistons, and ported 78 D80E heads. 464 lift Rhodes lifters and VVt270 cam. With a 4v upgrade, slightly losser converter in the C4 and even 4.10 gears I could never get it past 15.30's.

The porting helped, because when I swapped the stock 79 heads back on, it slowed down about 3 tenths.

Most likely, you have 9 to 1 or lower compression. I calculated it at 8.7 to 1. You have a stock deck height piston setup, and 69 or 70 cc head volume. This is the crux of the problem.

Next item, and it took 15 years to figure it out, even though I had a valvetrain ok to 6000 rpm plus, the stock tach is about 3-500 rpm high at around 6k. If the cam and springs are good, get a tach or shiftlight and start using the powerband. I got about 2 tenths this way.

With exactly the same shortblock in the 82, 400 lbs lighter, more converter, and Iron Gt 40 heads, its in the 12's.

 

[Mustang5L5]

'78 heads????


Why?? Your E6's are a better head than those.

 

[Daggar]

Save your nickels and dimes for a set of TFS heads. They'll mate to the 86 flat-tops and will give you lots of room to grow if you later decide to go with a different piston with valve reliefs.

 

[mercurycapri]

man I hate learning my mistakes I should have just bought the E7's I heard that the E6's were the worse heads for flow. I was thinking that I would have increased my compression ratio because of the smaller cc's since my pistons have no notches it should be pretty good ratio. Well I will ask stangjunkie about his heads I hate to dig into this motor again but a man got to have his power.

 

[fastranger347]

what do you meen by """killer deal" and "shoulda bought" you can get e7's practicaly for free, usually less than 75$ around here, they came on every windsor style v8 built in and after 87(f150's,e150's,302's,351's etc) the only other mass production head that was on a pushrod v8 was the gt40 on the cobras and the gt40p that was on the explorers