Rebuild Needed/Looking for advice

[SVT Sam]

Well,as it turns out, I chewed up a rod bearing. Had been chasing a tap for a coupleof weeks, but finally nailed it down to a rod bearing more than likely (Could be main, but definitely a bottom end bearing).

Cutthe oil filter open earlier this week and it has a spectacular glitter sheenwith some flakes.

Ihave been debating on selling and taking a loss (just bought the car a fewmonths back) but I think I have started leaning towards pulling the engine andtearing down myself. I have done a fair amount of engine work in the past, butthis will be my first attempt tearing down a 4V Mod.

So,I am on a budget, but I do have a few options. I am borrowing a car from afamily member at the moment. Not sure how long that is going to last, so Imight need to pickup a $1k beater to drive and build over time.

I'mreally concerned with just getting the Cobra back on the road, but I would hateto tear it apart and just re-use stockpistons rods and crank. I would like to have the funds to at least add rods andpistons, but that gets expensive quick.

Wouldit be worth swapping in a Termi shortblock? I have found a few local, not sureof the price yet. If I'm not mistaken, the flywheel would need to be changed,but I am really not sure about everything else involved in swapping in a termiblock. I know those guys are boosted, but I've also heard the pistons weren'tthe greatest either.

Idon't want to say I am trying to do this as cheap as possible, I want it tolast, but I don't have 3 or 4k sitting around to throw at it either.

Whatare my best options here? I'm about ready to pull the engine, get it on astand, and pull the oil pan to check the damage.

 

[black4vcobra]

Cheapest solution is to pickup a junkyard Mark VIII motor and swap your heads, intake manifold and flywheel. That way you can rebuild your motor with forged pistons and 03/04 Cobra (or Boss) rods. Others should be able to chime in with more details.

 

[01yellercobra]

Swapping in an 03/04 shortblock is a bad idea. Especially if you're staying N/A. You'll be getting lower compression and more weight. Unless your stock crank is trashed beyond repair then you don't need to replace it. It's forged and will take whatever you're going to throw at it. I think you can pick up rods and pistons at places like Mod Max for less then $1000. What kills though is all the small stuff like bearings, new main and head bolts, fluids, etc. If you want to rebuild then pick up a beater first and go from there.

 

[SVT Sam]

Cheapest solution is to pickup a junkyard Mark VIII motor and swap your heads, intake manifold and flywheel. That way you can rebuild your motor with forged pistons and 03/04 Cobra (or Boss) rods. Others should be able to chime in with more details.

What's an average price for picking up a MarkVIII motor?

Swapping in an 03/04 shortblock is a bad idea. Especially if you're staying N/A. You'll be getting lower compression and more weight. Unless your stock crank is trashed beyond repair then you don't need to replace it. It's forged and will take whatever you're going to throw at it. I think you can pick up rods and pistons at places like Mod Max for less then $1000. What kills though is all the small stuff like bearings, new main and head bolts, fluids, etc. If you want to rebuild then pick up a beater first and go from there.

Boost is in the future, but I also agree. I wouldn't want to drive a car around that felt like a dog because of lower compression until it see's boost. That wouldn't be fun.

I don't think the crank is totally messed up. I don't think the bearing has actually spun either. I believe it just started to delaminate from oil starvation. I think worse case scenario, the crank just needs to be turned a bit.

What about picking up a set of used 03/04 rods? I've read the 01 crank will need to be rebalanced due to the extra weight of the forged rods. Other than that are the rods direct bolt in? Trying to keep the machine shop bill to a minimum although I know it will not be cheap.

I hear ya on the nickle and diming on the small stuff. Bolts, gasket sets and bearings start to add up quick.

 

[01yellercobra]

The 03/04 rods are a good pick up if you can find them cheap. They're Manley rods. Even with boost I wouldn't want that low of compression. I'm running 9.5. I wouldn't go lower then 9.0 even with a PD blower. You'll have to get everything balanced anyway. You'll need the new rods and pistons. Some places want the rings and rod bearings so they get it all dead on.

 

[notchstang92]

I wouldn't use the 03 shortblock. As others have said the compression is low and the pistons aren't the greatest. It's also 80#s heavier than your aluminum block. If your block and crank are good then keep them. You can pick up a rod/piston combo for under $1000, just make sure you get forged. Now with tuning and fuel options a compression ration of 9.5 is pretty common with boost. You will need all new gaskets, bearings, etc. Now is a good time to get your cams degreed properly too.

Now if you found a complete 03 motor with the eaton on it then I'd consider it even with the extra weight.

 

[Regulars520]

If you install a mark motor you will need new flywheel, clutch etc because the mark is a 6 bolt crank and usually 10 1/2 inch clutch versus the cobra 8 bolt crank and 11 inch clutch.

 

[Regulars520]

Also since you are on a budget, these motors are aluminum and noise travels thru these blocks. Sometimes what you would swear to be a rod noise can be coming from the timing system. The guides are made of plastic and can wear, under the plastic is metal, when its worn down to the metal it creates a gap and can cause the chain to slap and it will sound like a rod knocking. So pull the timing cover first aftr its out before you drop the crank. Check your timing guides, etc... Even if you find it was a timing noise since you have discovered metal that means the system is contaminated. I would pull the crank, have it turned which usually runs about 150 ish and then buy matching bearings. While the crank is out try and flush the motor the best you can, to get all the debris out. Your on a budget so this is the cheap easy way to do it but not the real way. Real way would be full disassembly.