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Practicing Infidel
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Discussion Starter #1
I've been doing the same mileage and performance mods to my 1990 5.0 litre Lincoln Town car as I did to the Bronco.

I was surpised to see that a 1990 TC had way less hp than a 1990 Bronco or 1990 Mustang. From what I'm told a lot has to do with the cylinder heads and cam.

I have no desire to put the computer, cam and throttle body from a Mustang into a heavy Town Car, as I'm somewhat interested in mileage.

I am interested in changing to truck cylinder heads as they're cheaper and easier to find than Mustang heads. I've also read the truck and stang cylinder heads are nearly the same, is that true ?

I'm guessing if I keep my foot out of the loud pedal the mileage should be no worse with the better flowing truck heads (am I right?), but the flow will "be there" when I want to step into it.

Another reason I want to swap to truck heads, if it's possible, is I can get a pair for reman'd heads and stick them onto my still low mileage engine (102,000 miles).

I figure there's plenty life left in the rings as the TC is in exceptional shape, but the seals and guides are probably due. Also it'll give me clean, carbon-free ports and chambers again and fresh cut valve and seat faces again for better sealing.

Will truck heads bolt onto a low-po Lincoln 5.0 litre block ? Are the chambers the same size (cc's). Are the valves any bigger ? Do the ports flow better ?

Is this a sound idea Gurus ?

Thanks

Sixlitre
 

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I'm sure they will bolt right on with no problems. However, I don't think the heads are that much different as far as specs go. I don't think your TC has a roller cam, as on the HO motors, or a roller chain. BTW, the edelbrock timing set has Ford part numbers on it. Any way to reduce friction will help. I think your engine is basically a non-HO. (Crown VIC, Grand Marquis, Town Car)
 

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Wrenching for a Livin'
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Do you know what heads are currently on your lincoln?

I know most trucks and broncos had E7 heads along with mustang gt's. older 80s trucks and broncos(before FI had some less desireable heads i think) The cobras and lightning's had gt-40 heads. Some later model 5.0L explorers had gt40-p heads that use special style headers.

E7's are very plentiful, you can prob. find a set already rebuilt for 400 or less
 

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Practicing Infidel
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Discussion Starter #4
magnumpi said:
Do you know what heads are currently on your lincoln?

I know most trucks and broncos had E7 heads along with mustang gt's. older 80s trucks and broncos(before FI had some less desireable heads i think) The cobras and lightning's had gt-40 heads. Some later model 5.0L explorers had gt40-p heads that use special style headers.

E7's are very plentiful, you can prob. find a set already rebuilt for 400 or less
I'd bet my lefticle this engine's never been opened

so I'm guessing I have lo-po 150 hp:brownbag Lincoln/CV/Marquis heads, like 95 is talking about.

You answered my question about the name of the truck heads, the E-7s. I was told they were much better than the low-po Panther (CV/Marquis/Lincoln) heads.

Do you think they bolt on without changing my compression ratio due to different chamber volumes. Has anyone got spec tables for the differences in the chambers, ports, valves etc ?

Thanks

Sxilitre

p.s./
BTW if I can't beat $400.00 for a set of re-man'd heads I'll turn in my cheapest [email protected] on the board badge !
 

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Wrenching for a Livin'
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i have no clue about the compression ratio difference between the heads cause i don't know jack about your current heads, but i don't think it will make a big difference one way or the other. You'll still be able to run 87 octane
 

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the short block will be the same so just check into the stock cr for any 87 up fox stang which is i believe 8.5:1. its not hard to do the whole swap. and you can get the stuff dirt cheap. i have already gotten a harness, e7s, a9l computer, cam, and intake setup for $300 for everything. try checking out corral.net.
 

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There is a chance you could have e6 heads, likely not, but possible. FYI, mustangs use truck heads (e7's), so an e7 is an e7 pretty much. You also may have the more restrictive 58mm throttle body and upper. if you do, swap on an 87+ mustang upper/throttle body, they are 60mm. Verify which heads you have. Which autolite spark plugs do you use? the e6 and e7 heads will use a different plug.

Also, you may be flat tappet. WHile ford pretty much got rid of most of the flat tappet 5.0 blocks by 90, I've heard of a few hear and there slipping. by. To properly convert your block, you'll have to swap in a HO roller cam, then change the timing order to a HO timing order, verify your heads, etc.

Want a HUGE increase in power? grab some 96-01 ford explorer 5.0 heads. 96/early 97 heads are the gt40 irons from the factory, (three bars on the front of the head) 97-01 are the gt40p heads (4 bars on the front), and those heads will require special headers due to the spark plug angle.

as well, swap on the explorer intake, it flows nearly identical to a gt40 intake.
watch out if you have to deal with smog, only the 96/early 97 intakes have egr internally. As well, the gt40/gt40p heads aren't drilled for the bypass tubing in the back.
 

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Practicing Infidel
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Discussion Starter #8
v8only said:
Which autolite spark plugs do you use? the e6 and e7 heads will use a different plug.
Thanks V8only

I never thought of that. I know my 86 Bronco's 5.0 litre uses decidedly different plugs than my 90 Lincoln 5.0 litre. Good thinking !

I've actually been googling around and I've discovered that in all likelyhood my Bronco has the E6 heads, which aren't all bad for torque and swirl, by what I've read.

I also read that it's likely everything after 86 was treated to E-7 heads, unless, like you say they were unloading lessor heads on Lincolns and other Panther platform cars.

Still like to hear definatively my Lincoln heads are as good as truck heads, because I'd read differently before.

I'll price some of those Exploder heads remanufactured just for the fun of it.

Thanks

Sixlitre

p.s/
91Nite

I found a lot of dead links at the corral, but thanks it got me to other places.
 

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Wrenching for a Livin'
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Sixlitre said:
I'll price some of those Exploder heads remanufactured just for the fun of it.
Junkyards are your friend :thumbup

might luck up on a set...give 100 bucks for 'em and replace the valve seals, slap 'em on a run 'em.

Actually, if you can get a good deal on a 'yard 5.0L explorer motor might want to yank the whole thing. Gt-40 heads and intake, roller cam, all there already put together....just a thought
 

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Practicing Infidel
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Discussion Starter #10
magnumpi said:
Junkyards are your friend :thumbup

might luck up on a set...give 100 bucks for 'em and replace the valve seals, slap 'em on a run 'em.

Actually, if you can get a good deal on a 'yard 5.0L explorer motor might want to yank the whole thing. Gt-40 heads and intake, roller cam, all there already put together....just a thought
Good thought

It would probably be a good score

Sixlitre
 

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those explorer motors are gold.

FYI, those lousy e6 heads drop you 25 real horses. However, unfortunately, your 86 block in that bronco is sporting flat top pistons. "some" people have successfully put e7's on a 86 block, but more times than not, it results in piston to valve slap. Otherwise, if you want to play around, grab some e7's, but CLAY it up, and see if they'll fit the bronco. 25 horse gain. However, it may not be worth all the effort to find out they won't fit. As well, the e6 heads are great for emissions and torque, but if you look at the hp AND torque ratings for say an 86 5.0 vs an 87 5.0, both hp and torque went up with those e7 heads

I'm curious if truck and car heads are indeed different too.
 

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Wrenching for a Livin'
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also, there were some heads from the 70's...D00E casting i think that are like non-smog gt-40s of today....something like that, just something else to reserach and keep an eye out for
 

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Here is some good stuff from the corral...

Basically.....

The truck engines are roller blocks with a flat cam. The rest of the shortblock is just like the 'stang H.O. , including the E7 heads. The only other difference is the pistons are cast instead of forged, but they do have the same valve reliefs as a forged H.O. piston.

The passcar non- H.O all have roller cams, they are essentially the '86 Mustang H.O engine with a wimpier cam. They have the same crappy E6 heads, lower flowing upper intake, and 58mm tb just like the '86 'stang. Once again, the pistons are a cast version of the '86 pure flattops found in the '86 mustang. They also came with 17lb injectors instead of the 19's in H.O and truck motors.

So, if you took the passcar engine, tossed in an H.O. cam, dizzy, 19lb injectors , and EEC, you would have an '86 Mustang H.O engine.

If you tossed in the cam, dizzy, EEC, and upper and lower intakes from an H.O onto a truck motor, you wouls end up with an ''87-'93 spec. H.O engine.

The only things that would end up different would be having cast instead of forged pistons.

also, this site is right up your alley. It seems to confirm that 86+ f150's had e7 heads (interesting) while all towncars had the e6 heads. Seems like your bronco may be ok.

This site details an entire 5.0 HO conversion specifically for your towncar

http://www.lincolnsonline.com/tech/00066.html

Just a note, this says your engine has the flat top pistons...if that's true, be careful, the e7's may not work. However, if you want to get some compatible heads 100% for sure, twisted wedge heads will work with the flat top blocks.
 

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I have an explorer motor in my mustang. With only the addition of a crane 2031 cam, my car made 280hp/310tq to the wheels. So, if you were to change to a set of gt40p heads, and explorer intake and some sort of cam, you could expect damn good numbers. Btw, i got my 55k 97' explorer motor for $650.....what a deal, cheaper than buying heads lol!
 
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