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Discussion Starter #1
Ok so this past weekend, I was driving home and my timing chain jumped teeth when I shifted down to 4th gear, the car just died and hasnt started since. My mechanic said that when it jumped teeth, it bent my valves and that I have to rebuild my engine or by a new/used one..the car is a 1999 Mustang GT with a 4.6L 2V V8 engine. I love the car and I would like to rebuild it or drop a new engine in it. But funds are limited to about $700. So my questions are:

If I rebuild it, is it just the top end that I am rebuilding? and how much mite that be? I know ill need my heads done if the valves are bent.

If I buy a used one from a salvage yard, what other ford vehicles can I get the same 4.6l from? The f150 and Crown Vic are 4.6ls but the intake is a hell of alot different than my mustangs..can i use my old intake system?

And if I do pull an engine from a different vehicle like (F-150, Crown Vic ect.) will the motor mount rite in the Mustang? Idk if the mounts would be different for a truck or the crown vic..I dont wana pull an engine from a different vehicle and it not bolt up to my Mustangs setup..

If there is anything I left out or forgot to mention, please tell me!
Ive called every salvage yard within 500 mile range..litterally everywhere and nobody has a 4.6l 2V Mustang engine worth buying. Meaning I will probably end up rebuilding it, unless there is another vehicle that has an interchangeable engine..Im limited with funds, $700 is all I can really afford to do at the moment.

PLEASE HELP!!!
 

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Just rebuilding the heads would be fine I agree unless one of the pistons were damaged, which is possible cause the stock ones are crap. You can rebuild the heads at a shop for about 200 bucks. Check your local classifieds like craigslist and stuff you can usually find a good gt motor in there for 4-700 depending on the condition.
 

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you may not know what all will be needed until you take the heads off
 

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Also when u do what ever u decide to while u have the motor going in the car still out of it look for a gear drive timming setup (not sure if they have one for the mod motors) if u can get it it will stop this sort of thing from happning again
 

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Discussion Starter #7
BayyGT said:
Just rebuilding the heads would be fine I agree unless one of the pistons were damaged, which is possible cause the stock ones are crap. You can rebuild the heads at a shop for about 200 bucks. Check your local classifieds like craigslist and stuff you can usually find a good gt motor in there for 4-700 depending on the condition.
Thats what I will probably do..My uncle is a head mechanic at a shop in Phoenix, Az. The car is going to his house tomorrow and getting the heads pulled..
Ive been calling and calling and nobody has this engine. I think the car was drivin really hard by the previous owner though. It had 72k when i got it. This happened at 77,608 miles and I babied it most of the time.

But should I replace my pistons with forged ones even if the old ones are still good? If so, does anyone know where i can get them at a decent price?

Thanks again guys

---------- Post added at 10:13 PM ---------- Previous post was at 10:10 PM ----------

Also, will i need to buy an engine rebuild kit? Or just a certain gasket kit?
An engine rebuild kit is $800 on ebay..i dont want to buy one and only need a few things from it..

---------- Post added at 10:14 PM ---------- Previous post was at 10:13 PM ----------

Hawk said:
Also when u do what ever u decide to while u have the motor going in the car still out of it look for a gear drive timming setup (not sure if they have one for the mod motors) if u can get it it will stop this sort of thing from happning again
I have never heard of that..Im not sure if this model Mustang has that
 

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If your rebuilding damaged pistons or just replacing good pistons to be safe don't go forged unless your planning on putting serious power out down the road. A good cheap set of forged pistons will cost more then half your budget and may be wasteful if your not gonna mod your car much. Also I myself wouldn't get just forged pistons. Id get a full forged rotating assembly myself, your motors as strong as it's weakest point.
 

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Discussion Starter #9
t0t4lbl4ck0ut said:
If your rebuilding damaged pistons or just replacing good pistons to be safe don't go forged unless your planning on putting serious power out down the road. A good cheap set of forged pistons will cost more then half your budget and may be wasteful if your not gonna mod your car much. Also I myself wouldn't get just forged pistons. Id get a full forged rotating assembly myself, your motors as strong as it's weakest point.
Well i just found out what the official problem is. Cylinder number 1 has a crack in the top of the piston, you can see it with a light shinig down the spark plug hole. So i guess i am rebuilding it, the piston keeps coming up too high and hammering the spark plug closed, but when you re-gap it, it wont hammer it shut again unless you reach high RPM's. And yeah i see your point, i looked up forged pistons.VERY expensive lol ill just buy a stock piston for like $50 or $60 haha

Now my question is, do i have to replace all of the pistons when i do this, the one piston is obviously coming up higher then its suppost to so something under must be giving out?

The car runs fine if you keep it under lile 3k RPMS, of you go over it, it will hammer the plug shut.
 

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I would honestly change them all due to different cylinder compression. Just a safety measure for the future. Hypereutectic pistons are fairly cheap and alot of people like them over forged if your not boosting it out the a**. Do you plan on supercharging it ever? Cause if so you might wanna look at lowering your compression now and just take a 3% hp loss for now. Hypers can handle alot of proper power and you can get dish pistons to give you added clearance for your plugs.
 

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I would change them all and look for another problem as well. A piston should not be able to strike a spark plug. Theres something else wrong. At this point i would say just find a motor and swap it in rather than go through all the trouble
 

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Discussion Starter #12
onesickstang01 said:
I would change them all and look for another problem as well. A piston should not be able to strike a spark plug. Theres something else wrong. At this point i would say just find a motor and swap it in rather than go through all the trouble
I have called litterally every junk yard within a 7 hour drive. Not one yard has one under 150k for under $1500. It would be cheeper to rebuild the insides. I think it may be the crank but I wont know until i pull it apart. Since it only does it on high RPM's i think something is getting hot and going too fast at a high temperature and maybe stretching letting the piston reach farther up. Ive drivin it all day today with no problem but i had to keep the rpms low. Its deffinately the strangest thing ive had a car do lol

---------- Post added at 08:08 PM ---------- Previous post was at 08:07 PM ----------

t0t4lbl4ck0ut said:
I would honestly change them all due to different cylinder compression. Just a safety measure for the future. Hypereutectic pistons are fairly cheap and alot of people like them over forged if your not boosting it out the a**. Do you plan on supercharging it ever? Cause if so you might wanna look at lowering your compression now and just take a 3% hp loss for now. Hypers can handle alot of proper power and you can get dish pistons to give you added clearance for your plugs.
I would like to supercharge it in the future. So that would be a smart idea. But why would i losse hp? Just curious
 

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It would not be cheaper to buy a new block at all. I'd honestly just check it for any other issues and the plug issue I'd say you probably have the wrong plugs. New pistons will be the cheapest way especially with free labor

---------- Post added at 01:18 AM ---------- Previous post was at 01:13 AM ----------

Because by dropping the combustion chamber compression you lose output from a naturally aspirated engine. Less compression means less concentrated energy in the cylinders which means less power. Your stock compression is 9.4:1 a good low compression motor for forced induction is around 8.5:1-8.8:1 to can go higher but it just puts alot of strain on the motor and at lower compression forced induction has a much greater effect
 

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Discussion Starter #14
t0t4lbl4ck0ut said:
It would not be cheaper to buy a new block at all. I'd honestly just check it for any other issues and the plug issue I'd say you probably have the wrong plugs. New pistons will be the cheapest way especially with free labor
Nope. Ive got the rite plugs. It ran fine with old plugs for thousands of miles and after this happened. We pulled them out and #1 was beaten shut. I bought all new plugs, all 8, and it ran fine with them for a while, i pulled them out and they were fine. But when i put them back in, i took it to 4500 through 1st, 2nd, and 3rd. Then it ran funny, we pulled the plugs and sure enough, #1 was beaten shut. If they were the wrong plugs, they would all be beaten shut. Something is wrong under that one piston.
 

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Car-parts.com

Its a search engine for all the junk yards. You can check any area. Might want to check craigslist and such as well. I know in my area i was looking at several for under 1k with less than 100,000 miles
 

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Discussion Starter #16
onesickstang01 said:
Car-parts.com

Its a search engine for all the junk yards. You can check any area. Might want to check craigslist and such as well. I know in my area i was looking at several for under 1k with less than 100,000 miles
Ok thanks bro, and yeah i have like 3 adds on craigslist letting people know im looking for one
 

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If you do take the heads of get the machine shop to put the after market spark plug inserts in or you will be very sorry later when a plug blows out on you
 

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Just rebuilding the heads would be fine I agree unless one of the pistons were damaged, which is possible cause the stock ones are crap. You can rebuild the heads at a shop for about 200 bucks. Check your local classifieds like craigslist and stuff you can usually find a good gt motor in there for 4-700 depending on the condition.
I also have a question what if i was lookin at a 2003 mustang gt but guy says bent pushrod what all would need to be done to have that rebuilt or whatever at a shop idk much about cars so idk
 

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I also have a question what if i was lookin at a 2003 mustang gt but guy says bent pushrod what all would need to be done to have that rebuilt or whatever at a shop idk much about cars so idk
Well 1, this is a 10 year old thread... But props for googling I guess which I suppose brought you here. 2 - if you dont' know much about cars don't buy an almost 20 year old Mustang GT. 3 - The 2003 Mustang GT is an overhead cam engine, there are no pushrods. Something else is wrong. Do not buy this car. Bad engine is a full rebuild or a swap to a used engine, either of which is going to be $thousands from a shop.
 
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