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vinnietbird
10-11-2005, 08:29 AM
Will the Gt40 iron heads from an Explorer work with flat top pistons in my T-Bird?

V8Demon
10-11-2005, 08:41 AM
Depends on the cam your gonna run. What do you have in store?

vinnietbird
10-11-2005, 09:08 AM
I wasn't planning on changing cams right now.The engine in my '88 'Bird is an H.O. from an '87 Lincoln LSC.I'm using the Explorer intake on it already.Factory headers,H-Pipe with hollowed cats,dual exhaust.What do you think?My pistons wouldn't hit the valves would they?

CougarCoupe88
10-11-2005, 10:22 AM
if it's a true Ho you should be good with the stock cam. people do it all the time. and the motor should have the valve relifes in it. only the good HO's got them.

vinnietbird
10-11-2005, 10:39 AM
I don't want to change my cam,I just want to know if I can use GT40 iron heads on my H.O. with flat tops.

Ether947
10-11-2005, 10:44 AM
Yes you can.

vinnietbird
10-11-2005, 10:49 AM
That's great.I keep hearing conflicting stories,and don't really know what to do.I can get the very low mileage heads for $150.00,ready to go.1/2 the people say no,the other half yes.I haven't found any print that says either way.

Tbird232ci
10-11-2005, 10:52 AM
an 87 HO should have valve reliefs, not the flat tops you think of in a standard output engine, or an 86 GT engine

vinnietbird
10-11-2005, 11:05 AM
Well,actually,I say it's an '87 engine because it came from an '87 car,but,it does have flat top pistons.

Sick88Tbird
10-11-2005, 03:01 PM
Make sure you get the GT-40P specific headers. I believe Mac makes a set of full-lengths that are compatible as well as BBK(if you have a stick). Ford racing also offers shorties for those heads but they are rediculously expensive.

vinnietbird
10-11-2005, 08:32 PM
These are not the "P" heads.Just the cast iron GT40 heads.

Sick88Tbird
10-12-2005, 07:52 AM
No need to worry about headers then...if ya find anyone with the "P" specific headers let me know...lol.

cougarman
10-12-2005, 08:43 AM
No need to worry about headers then...if ya find anyone with the "P" specific headers let me know...lol.

BBK shortys fit the P heads just fine.:D

Innes
10-14-2005, 11:51 AM
i just pic-ed up GT-40 heads to off an explorer i notetied the rockers on them have a 5 on them does that mean ther 1.5 rocker ratio. cause i wannted to put on 1.7's rollers. i know the cobra came like that but are the heads exacly the same.am i going to have piston problems and do i have to machine the heads (push rods ect.) to make the 1.7's work.havent decided want kind of cam yet.

TurboCoupe50
10-14-2005, 12:48 PM
For the price I'd grab 'em, but you are taking a risk of using them on the flattops. Only way to know for sure, would be to clay the pistons with a head installed and very gently turn the engine by hand. Then you remove the head and measure the thickness of the clay where the valves made the indentions, anything .100 or more and you're OK.

BTW. The '87 LSC 5.0 is the flat top piston 200hp engine, same as the '86 Stang and LSC. The Mark VII DID NOT get the 225hp HO till '88....

vinnietbird
10-14-2005, 03:00 PM
Thanks a lot.How much do these heads go for usually?If I can't use them,I'll sell them and try to at least get my money back.Thanks.

vinnietbird
10-14-2005, 03:02 PM
I've got the Explorer intake on it,and it's running great.How much horsepower would you guess the heads would make....if they will work?

TurboCoupe50
10-14-2005, 07:47 PM
I've got the Explorer intake on it,and it's running great.How much horsepower would you guess the heads would make....if they will work?

Over the E6s I'd guess 35-40 hp with the stock HO cam, the Explorer intake and a 65mm T-body. You may need to increase the fuel pressure 3-4 lbs to get max HP. Ideally with head mods you should go with Mass Air.

I sold a well used set of the std GT40 irons for $300 about a year ago.

vinnietbird
10-15-2005, 08:44 AM
I'll go get them.I may have to wait to install them,because I don't have anything for Mass Air yet.I was planning on that for next spring.Do you think the car would run well enough without Mass Air until then,or wait?I want more horsepower (doesn't everybody?),but have to go one step at a time.With the kids in school.and a LOT of expenses,that's just how it has to be.I'll start watching E-Bay and gathering parts,like the Mass Air wiring kit,Mass Air Sensor and intake tubing,then the computer.For now,the heads are on my list first while I have access to them.I have E7 Heads in the garage,but,i figured if I'm getting the GT40 heads,I'll go ahead and get the new seals in the E7's and only use them if the GT40 heads don't work out for me.

86Tbuzzard
10-16-2005, 01:43 PM
If I use the explorer cam with the GT40P heads, and the explorer intake...would that mess up the pistons?

vinnietbird
10-18-2005, 02:35 PM
Well,I can get the heads for $100.00 if I pull them myself....NO PROBLEM !!!! I wonder if my combo ('86 H.O.,Explorer intake,Explorer GT40 heads) would run decent without Mass Air.Anybody?Turbo Coupe50?

t-bird85
10-18-2005, 02:52 PM
I dont understand something, If your going throught the trouble of changeing your heads why not just do a clay test and save your self the dought, Every motor is different to say your not going to have PVC problems. To many factors to take into account. I agree with coolcat that you wont but its better to be safe.

vinnietbird
10-18-2005, 08:01 PM
I thought I already stated I was going to use the clay.My mistake.Yes,I plan on it.Cheap insurance.

TurboCoupe50
10-19-2005, 01:44 PM
Well,I can get the heads for $100.00 if I pull them myself....NO PROBLEM !!!! I wonder if my combo ('86 H.O.,Explorer intake,Explorer GT40 heads) would run decent without Mass Air.Anybody?Turbo Coupe50?

As long as you keep the HO cam and 19lb inj it should run fine on the S/D. You should install a adj fuel pressure regulator, and increase the F/P to 42-45 lbs to get max power out of the combo.

vinnietbird
10-19-2005, 01:53 PM
I'll look around for one of those.A good used one would be nice right about now.I'll check E-Bay.Thanks a lot.TC50.I have a lot to give you credit for on my 'Bird.You've helped more than you know in the past few months.Thanks a lot.