Alright I really really need some help.... I have a 1998 mustang cobra and well it more like a nogo...cobra... I kinda slung a rod through the side of the block...well both sides of the block. I removed the old motor took off everything and then waited for a month or two and got a shortblock out of a gt. I inspected the heads and cleaned everything up real nice and pretty and everything looked damn good, so I put it together with my heads and everything else that came off my old motor.... Well it seems that I probably screwed up something really really bad and the son of a bitch (excuse the french) hardly runs. It will not idle. It has no throttle response, it sounds like its knocking a tad bit, but a friend of mine who's been through a lot of motors in his cobra said that the knocking sound is normal for a freshly rebuilt engine. So now I am totally stuck on the situation and I am about ready to say F#CK it if you understand where I am coming from. Now I have had a couple of mechanics and some stupid asses tell me about six or seven different things it could be. One told me it was the timings off, one told me it was a rod knock, one told me I could have some bent valves, hell one told me it was fine and dandy I just needed to let it run for a while. Well I am finally gonna get to the questions and the point I was getting at... For one if anyone knows what is wrong with is or what I can do to fix this. Has anyone else had a pretty much bone stock cobra motor sling one rod through TWO sides of the block? Please I really need some help, I am in the biggest bind of my life. No car, and no other means of transportation.
Motor in my 98
- Thread starter snakebittn
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Blk98Cobra
Bye
wait wait wait.......you said you got a shortblock out of a mustang GT????????? and put your heads on the gt's shortblock? I think that is your problem dude.....gt is a 2 valve motor.......cobra is a 4 valve motor.....
I'd have to agree with Brian ... BUT I'd think you would have checked into this before you put the GT shortblock together using Cobra parts:bash: ! I'd have to think that the GT block and the Cobra block are two different animals. The internal passages, the main bearing caps and lands (on the block), and who knows what else (exhaust and intake manifolds ?). I'd get a lot more positive information:read: :sleeping::read: before I went any further. Someone in here has the information, I'm sure.
This is just my opinion. No offense intended by the little Icons, but this just doesn't sound right.
Dan
This is just my opinion. No offense intended by the little Icons, but this just doesn't sound right.
Dan
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Blk98Cobra
Bye
Yea the 2 valve heads are totally different........cobra's have the 4 valve heads from 96+......the heads from a cobra will NOT fit a gt motor, srry to say man but you basically bought the wrong motor to put in your car
I was just looking through the Haynes repair manual, on rebuilding & reassembling engines (4.6 SOHC & DOHC). Of course they don't offer any information on swaping parts, but I didn't see anything that specifically said the Cobra parts won't work. I'd wait for a post from someone that has a little experience in rebuilding & swaping parts.
Dan
Dan
Even if it would work why the hell would you want a GT Shortblock. The aluminum Cobra block is more than stong enough for any power that you would ever want, and it is lighter. That is just stupid to me. And it is almost unheard of to throw a rod in one of these unless you are making some really seriouse power, or your tune is just completely F'd up. What all was done to the old engine? Mods' etc? Are you the original owner? This baffles me because I have never heard of suck a thing.
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Blk98Cobra
Bye
yea im pretty much calling bs on this........someone get out the bs flag.......
Don't see any reason to attack the "poster," by calling it all BS. Let's try to get some answers for him.:beer:
Dan
Dan
:lol: :beer: :lol:
How's this, Brian. LOL
Dan
How's this, Brian. LOL
Dan
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Blk98Cobra
Bye
Originally posted by Dano
:lol: :beer: :lol:
How's this, Brian. LOL
Dan
thank you
:lol1: Well I think ya'll answered his question love the BS meter, Dano, Nedded a good laugh.
Jesus christ u guys act like the 4v cobra motor is from a completely different engine family. There are very few differences in the overall scheme of things. This guy could hypothetically through all the top end pieces from his old engine onto a GT bottom end(Even though that might have to be one of the most retarded ideas I ever herd, so I call bs on this too) However, if its not Ill take a shot at what the problem might be. Lets say he got a short block out of a GT. I have a feeling that the cobra crank and the GT crank have different ballances. So my guess would be that he used his cobra harmonic balancer on the GT which has it out of balance. Just a guess but it seems like as good a shot in the dark as most. Back to this thread being BS though. If this guy new how to put a mod motor together, degree the cams and all the beyond backyard mechanic stuff, I would assume he would be smart enough to figure out what the problem is himself. So BS
sorry to but in but, It was my understanding that there called modular moters for a reasion. a 4.6 block is a 4.6 block. just like a 5.4 block is a 5.4. if we can drop navi dohc on a 4.6 the gt block should be the same. ?????????????????????.
P.S. IMO
P.S. IMO
provided that all the inturnals were good when they went back in the car. i would start looking at the cam timming.
http://www.modular4v.com/forums/ShowPost.aspx?PostID=286
take a look at this thread. (still learning myself)
http://www.modular4v.com/forums/ShowPost.aspx?PostID=286
take a look at this thread. (still learning myself)
I'm going with timming as well....With the bad idle and no power, that's where I'd start for sure.
And I thought the only diff btw the GT and the Cobra was the GT is iron and the Cobra has dual oh cams for better air flow (besides the internals like crank, pistons, etc.).
I think all else is equal and you can switch them around all you want.
And I thought the only diff btw the GT and the Cobra was the GT is iron and the Cobra has dual oh cams for better air flow (besides the internals like crank, pistons, etc.).
I think all else is equal and you can switch them around all you want.
lol this thread is comedy, I don't even know where to start.
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