Motor Question
6th Gear Member
Joined: Apr 2007
Posts: 10,468
From: California
RE: Motor Question
It's gonna be a bit hard to make 300 honest horsepower with stock heads. If the mild port/polish is done by a pro who knows what he's doing, then yeah, it can be done. Check the block out, if there's no obvious cracks in the cylinder walls, and it's not already bored way outthen $75 is a steal. You'll be better off starting with a roller block since you can get a factory roller cam/lifter setup for way cheaper than a retrofit. The block should already have the link bars and hold down spring/hardware. All you'll need is a cam/lifters and maybe new pushrods if the stock ones for the block happen to end up being too short. It happens. What are the heads you have? Early type heads with a late model block may need different length pushrods
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5th Gear Member
Joined: Aug 2006
Posts: 2,447
From:
RE: Motor Question
The block does not have a broken skirt. A piston does and the piston can be replaced.
If I go with the roller, I will still use my original 289 heads, but they will get a port/polish, a valve job, and hopefully some inexpensive roller rockers.. I believe the block will come with all the hardware, it is just disasembled.
Would by 68 302 pistons work If they were in good shape or is it worth another $300 on a rebuild kit that includes pistons.
If I go with the roller, I will still use my original 289 heads, but they will get a port/polish, a valve job, and hopefully some inexpensive roller rockers.. I believe the block will come with all the hardware, it is just disasembled.
Would by 68 302 pistons work If they were in good shape or is it worth another $300 on a rebuild kit that includes pistons.
6th Gear Member
Joined: Jan 2007
Posts: 5,469
From: AR
RE: Motor Question
To me the extra $75.00 for the roller is a good deal..... the cracked skirt of the piston should make no difference as long as the cylinders are not damaged.... Also, the chances are very good that you can use the stock roller can and lifters, this will save some $ (rollers do not wear like flat tappet cams)
There is a chance that your old motor has been bored in the past and already has .030 over pistons....
There is also a chance that the late model 302 has not been bored out, This being the case you can have the late 302 bored and the chances are good that used .030 pistons will work just fine this can save $
In other words, if all of the stars are aligned in your favor, the melding of the two engines could be very cheap for you.
There is a chance that your old motor has been bored in the past and already has .030 over pistons....
There is also a chance that the late model 302 has not been bored out, This being the case you can have the late 302 bored and the chances are good that used .030 pistons will work just fine this can save $
In other words, if all of the stars are aligned in your favor, the melding of the two engines could be very cheap for you.
Thread Starter
5th Gear Member
Joined: Aug 2006
Posts: 2,447
From:
RE: Motor Question
ORIGINAL: JMD
To me the extra $75.00 for the roller is a good deal..... the cracked skirt of the piston should make no difference as long as the cylinders are not damaged.... Also, the chances are very good that you can use the stock roller can and lifters, this will save some $ (rollers do not wear like flat tappet cams)
There is a chance that your old motor has been bored in the past and already has .030 over pistons....
There is also a chance that the late model 302 has not been bored out, This being the case you can have the late 302 bored and the chances are good that used .030 pistons will work just fine this can save $
In other words, if all of the stars are aligned in your favor, the melding of the two engines could be very cheap for you.
To me the extra $75.00 for the roller is a good deal..... the cracked skirt of the piston should make no difference as long as the cylinders are not damaged.... Also, the chances are very good that you can use the stock roller can and lifters, this will save some $ (rollers do not wear like flat tappet cams)
There is a chance that your old motor has been bored in the past and already has .030 over pistons....
There is also a chance that the late model 302 has not been bored out, This being the case you can have the late 302 bored and the chances are good that used .030 pistons will work just fine this can save $
In other words, if all of the stars are aligned in your favor, the melding of the two engines could be very cheap for you.
One of my pistons has a marking in the top and I beleive it may be stock. Will that marking tell me the oversize?
I have been told the engine got a new 302 short block in the early 70's, but I am not sure if it was a rebuild or truely a new block.
I will check over the cylinder wallson the 302 before I buy it. I need to check them out on my engine as well. If all else fails, I'll have an extra engine for the next mustang....
6th Gear Member
Joined: Aug 2007
Posts: 5,896
From: Elk Grove, CA
RE: Motor Question
Oh, ok, no worries about the cracked piston skirt
Go for it. $75 is a great deal on a complete roller block, and like JMD said, you can possibly use the cam and lifters (or at least the lifters) from the roller block, and maybe even use your existingpistons.
That said, I'd probably recommend aftermarket pistons for performance if you can afford it. It'll be easier to pick the right compression ratio with aftermarket pistons, and you'll probably be better off with some light hypereutectics rather than the stock cast units.
Go for it. $75 is a great deal on a complete roller block, and like JMD said, you can possibly use the cam and lifters (or at least the lifters) from the roller block, and maybe even use your existingpistons.That said, I'd probably recommend aftermarket pistons for performance if you can afford it. It'll be easier to pick the right compression ratio with aftermarket pistons, and you'll probably be better off with some light hypereutectics rather than the stock cast units.
5th Gear Member
Joined: Mar 2005
Posts: 3,566
From: Marquette Mi
RE: Motor Question
Just so you know, the 5.0 roller cam engine will need to use the balancer and flexplate/flywheel it came with. The early stuff wont interchange, so if you get the engine from him, make sure its a complete engine. The crankshafts will not interchange, the roller motors have a one piece rear main seal, the early engines have two piece.
Other than that, using the oil pan/pickup from your exsisting engine, its a bolt in deal. The stock cams werent wimpy (nor were they awesome) in the Mustang roller engines but upgrades are ok if you have the funds. A set of heads really wakes up a 5.0, thats the one I would go with if I were building a tiny engine. I have a few of both laying around, and I would do the late roller first, even with a carb.
Other than that, using the oil pan/pickup from your exsisting engine, its a bolt in deal. The stock cams werent wimpy (nor were they awesome) in the Mustang roller engines but upgrades are ok if you have the funds. A set of heads really wakes up a 5.0, thats the one I would go with if I were building a tiny engine. I have a few of both laying around, and I would do the late roller first, even with a carb.
Thread Starter
5th Gear Member
Joined: Aug 2006
Posts: 2,447
From:
RE: Motor Question
Sweet, I was planning on adding a T-5 since my tranny is gone so I was going to have to buy a new flywheel anyway. One of the reasons I pulled the engine was because of a very leaky rear main seal. I hear the one peice units are mush more resistant to leaks.
Thanks for the heads up about the oil pickup and pan. I was planning on eventually adding aluminum heads, so I think I am starting in the right place.
Thanks for the heads up about the oil pickup and pan. I was planning on eventually adding aluminum heads, so I think I am starting in the right place.
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