What other engines can be used in a 99 cobra? DOHC lincoln, mercury engines ...etc. looked through stickies but didn't find much.
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suitable engine choices
- Thread starter ls1htr
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depends what your looking for. you can make a 5.4l with c heads and a boss intake, you got the cobra r motor, fr500 motor, mach 1 motor, gt500, terminator. you can make anything fit with enuff money but if you looking for plug and play i would get a mach 1 motor and swap your intake cams into it. more power and better heads for about 3k.
yeah, not trying to reinvent the car. just a replacement 4.6.
i would look on ebay lots of cobra, mach 1, aviator engines
03 04 05 Aviator Engine 4 6L Vin H 8th Digit DOHC 125574 | eBay
that is what i was trying to find out. i was unsure if mark8/aviator engines would work.
yes but the mark 8 engine has b heads instead of c heads, aviator engine transfer intake and timing cover. i would get aviator over mark 8 engine
what year span of aviators should i look for. 03-05 is mainly what i am finding.
An aviator long block is a great replacement engine. It's exactly the same thing as a Mach 1 or Marauder long block, but since it comes out of an SUV, it's usually priced lower than a "cobra motor".
You might find one with the intake and all sorts of other stuff included, but you only need the bare long block. If it does come with all that extra stuff, you can sell it to recoup your costs.
There are only 2 small things you need to change to make it fit.
Flywheel: Since it comes out of a vehicle that has an automatic trans, it has a 6 bolt crank instead of an 8 bolt crank. So, you'll need to find a 6 bolt, 11" flywheel.
Exhaust Manifolds: The 03/04 heads have a different shaped exhaust port. Your original manifolds will physically bolt up to the newer heads, but I'm not sure if it causes any sort of restriction. Some people will say you don't need new manifolds, some people will say you will. I decided to just get a set of stock exhaust manifolds from an 03 Cobra for $20 instead of using my 99 manifolds, just to make sure.
You'll want to use your original front cover and accessories instead of the aviator front cover. Im not sure what the differences are, if any.
You'll benefit from the later heads and cams. It'll make more bottom end power, but it might not pull as hard up top. Overall, it's a great choice for a street replacement.
If you plan on adding boost, I wouldn't recommend this motor unless you're broke and this is the only way you can get your car running again.
There are other ways to go about it... 5.4 swap, etc. etc. etc. But this is by far the cheapest option if you want to start with a clean slate.
You might find one with the intake and all sorts of other stuff included, but you only need the bare long block. If it does come with all that extra stuff, you can sell it to recoup your costs.
There are only 2 small things you need to change to make it fit.
Flywheel: Since it comes out of a vehicle that has an automatic trans, it has a 6 bolt crank instead of an 8 bolt crank. So, you'll need to find a 6 bolt, 11" flywheel.
Exhaust Manifolds: The 03/04 heads have a different shaped exhaust port. Your original manifolds will physically bolt up to the newer heads, but I'm not sure if it causes any sort of restriction. Some people will say you don't need new manifolds, some people will say you will. I decided to just get a set of stock exhaust manifolds from an 03 Cobra for $20 instead of using my 99 manifolds, just to make sure.
You'll want to use your original front cover and accessories instead of the aviator front cover. Im not sure what the differences are, if any.
You'll benefit from the later heads and cams. It'll make more bottom end power, but it might not pull as hard up top. Overall, it's a great choice for a street replacement.
If you plan on adding boost, I wouldn't recommend this motor unless you're broke and this is the only way you can get your car running again.
There are other ways to go about it... 5.4 swap, etc. etc. etc. But this is by far the cheapest option if you want to start with a clean slate.
no boost or nos. thanks for the info, that is what i needed to know. when you put "cobra" in the same sentence as motor it seems that the cost triples.
on the subject of exhaust manifolds. will my h pipe from the 99 bolt directly to 03-04 manifolds?
assuming you still have your 99 motor complete......to make the power you have now.
You want to keep your c-heads, cams, and entire intake....they should fit on any x-93 Mk 8/aviator, 03-04 maurader/mach 1, or earlier 96-98 cobra short block...if sticking to AL blocks
Mk 8 /aviator will be 6 bolt crank... I believe.... as opposed to 8 for the others...
You want to keep your c-heads, cams, and entire intake....they should fit on any x-93 Mk 8/aviator, 03-04 maurader/mach 1, or earlier 96-98 cobra short block...if sticking to AL blocks
Mk 8 /aviator will be 6 bolt crank... I believe.... as opposed to 8 for the others...
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DOHC blocks listed...yes...
read this for info from NASVT..for info and online motor locator site:
http://www.svtperformance.com/forum...86-99-cobra-vert-catastrophic-engine-stb.html
comment #18
http://www.svtperformance.com/forum...detailed-march-issue-popular-hot-rodding.html
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I believe the 6 bolt cranks aren't forged. It may not be an issue for you though.
The mark 8 and aviator engine are completely different. If he got the aviator engine he wouldn't need his c heads because the ones on the aviator are the same as the 03/04 cobra,mach 1
Engines from Marauders, Mach 1's, Aviators will all bolt in. The Aviator engine, as stated above, requires some work and probably additional cost also before it will be in working order.
The Marauder, Aviator and Mach 1's with auto transmissions have cast cranks that take a 6 bolt flywheel. Your flywheel has 8 bolts so you'll need a new one with these engines.
Regarding the exhaust manifolds, yours will fit and not create and obstruction when installed on 03/04 heads without any modifications.
check Car-Part.com--Used Auto Parts Market for engines
If you use a Mark 8 bottom end, will a 01-04 gt flywheel work?
yes
thanks for all the info. it is very helpful.
also the original engine is still in the car. i bought it with a hydro-locked motor. i am going to toss the jlt water vac air intake and put the oem air box back on. it is a nice car and just going to make a stock driver out of it.
also on a side note, i have pulled plenty of sohc motors out of the top. will the dohc motors come out the top or do you have to drop the k-member and go out the bottom?
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