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Engine Piston Identification Help(Roller 5.0)

  • Thread starter Thread starter 83RagTop5.0
  • Start date Start date Jun 29, 2019
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    302 5.0 flat top piston roller block
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83RagTop5.0

Member
Jun 29, 2019
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Jun 29, 2019
#1
  • Jun 29, 2019
  • #1
Hey there guys, new to the forum. Excited to be here.
A little bit of a back story in the situation.
I have a 1983 convertible 5.0 4 speed. I bought the car about 9 months ago. Drove it 50 miles and the engine became off balance and insisted on dying unless under heavy throttle. Did my first engine tear down and saw damage on the outside of piston #4 and several scratch’s inside the block as well as a snapped oil pump shaft that connects to the distributor.
After reading about roller and non roller blocks and builds I came to realization that instead of rebuilding the block I had I was better off trying to locate a roller block to rebuild and reinstall. After browsing around I came across an add on offer up and was interested but I am very confused as to the pistons currently in the block and am looking to you guys to hopefully give me a hand here.
Thank you for reading!
 

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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,167
17,861
224
Massachusetts
Jun 30, 2019
#2
  • Jun 30, 2019
  • #2
Those are the pistons used in non-HO applications like 5.0 thunderbirds, crown Vic's, cougars, town cars.

Those pistons might have been used in the 1986 5.0 HO in the mustang. Unsure on this
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,829
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polk county florida
Jun 30, 2019
#3
  • Jun 30, 2019
  • #3
^^I agree^^ and will add they are low compression and may have piston to valve issues when using bigger cams and/or heads with bigger valves.
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Jun 30, 2019
#4
  • Jun 30, 2019
  • #4
based on the combustion chamber that is likely an E6TE cylinder head... called them turbo swirl heads, undesirable and did come on the 86 HO but i dont remember the pistons used.
 
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83RagTop5.0

Member
Jun 29, 2019
22
2
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Seattle
Jun 30, 2019
#5
  • Jun 30, 2019
  • #5
Thank you for the info so far guys! I wasn’t expecting anything this soon! How awesome.
So both the pistons and heads in this motor are both undesirable? He wants 600 for the whole package. If I’m thinking this through correctly. I’m probably better off just finding a bare or close to bare roller block and building it myself? I keep seeing just the blocks from 100-250 in my area.
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
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Hillsborough county
Jun 30, 2019
#6
  • Jun 30, 2019
  • #6
Your best bet is to get an Explorer engine from a 95 for around that year out of the junkyard. They are with a Cam change and 93 Cobra motor
 
Reactions: General karthief

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,167
17,861
224
Massachusetts
Jun 30, 2019
#7
  • Jun 30, 2019
  • #7
$600 is too much for the flat pistons and e6 heads.

I second explorer motor. Try to find an early one with the gt40 heads. A cam swap, better valve springs, and crane Cobra 1.72rrs and you basically have a 1993 cobra engine.
 
Reactions: Exrace89GT
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83RagTop5.0

Member
Jun 29, 2019
22
2
13
Seattle
Jun 30, 2019
#8
  • Jun 30, 2019
  • #8
Is there a specific early set of years I should be looking for on explorers? We have many of them in the area in junkyards. Is it fairly easy to convert EFI over to carb?
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,829
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polk county florida
Jun 30, 2019
#9
  • Jun 30, 2019
  • #9
If your car is carb now just swap the parts to the explorer engine. Only issue will be the timing cover and the the gizmo that bolts to the cam that drives the mechanical fuel pump, there was a low pressure in tank fuel pump used I believe on the cfi model but not sure, also make sure you use a distributor with the correct cam drive gear for the roller cam. And make sure you have the correct water pump for the accessory drive too, standard or reverse rotation.
look here for more infohttps://www.stangnet.com/mustang-forums/threads/technical-thread-how-to-index.808661/
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,167
17,861
224
Massachusetts
Jul 1, 2019
#10
  • Jul 1, 2019
  • #10
Carb swap is easy. Just swap the intake manifold and carb of your choice over along with the accessories and the correct timing cover to drive the mechanical fuel pump. You'll want to swap the cam out as well.

You really only want the explorer long block here, and try and target an early model with the GT4- heads.

Best way to ID them is to look at the front of the heads mounted on the engine. GT40 heads will feature 3 bars, vs the 4 bars on the GT40P head.

The only issue with GT40P heads is the spark plug angles. You'll need headers designed for them like the MAC gt40P headers or the now-discontinued ford racing gt40P header. If you have a set of those, then just grab whatever explorer long block you desire as the gt40P's have a slight compression bump over the 40's.
 
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83RagTop5.0

Member
Jun 29, 2019
22
2
13
Seattle
Jul 1, 2019
#11
  • Jul 1, 2019
  • #11
I’m relieved that the carb swap from EFI is fairly simple as this is my build. I found an explorer today. The guy is asking 300 which seems more than fair. It’s a 97 explorer with the 5.0. I’m not sure if this is the earlier models that are being referred to but it should at the least have a roller 5.0 correct? He says the head gasket blew and it hasn’t been driven since. 240k miles. Is this the direction I should be looking to? I can get a VIN updated to the post when I get home from work.
Really everyone’s input and info has been a real life saver here. Thank you so much
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,829
10,509
203
polk county florida
Jul 1, 2019
#12
  • Jul 1, 2019
  • #12
Yes, that would be a roller engine. I believe that would be a gt40p though, you just need to get the p headers. I think the headers may be hard to find, I spent a couple minutes and did not find any.
There is one company that makes headers for them, he is a member here, I will try to find him.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,829
10,509
203
polk county florida
Jul 1, 2019
#13
  • Jul 1, 2019
  • #13
RCI Custom Racing Headers
 
8

83RagTop5.0

Member
Jun 29, 2019
22
2
13
Seattle
Jul 2, 2019
#14
  • Jul 2, 2019
  • #14
That’s rather unfortunate about the P heads. But the only hiccup would be the headers correct? The rest of the process is the same?
This build will take me some time due to work, I guess I could keep looking for headers but if it comes to it I could always get a set custom made? Looking into the RCI custom ones now.
Also what cam and springs should I be looking at for this block?
 
8

83RagTop5.0

Member
Jun 29, 2019
22
2
13
Seattle
Jul 2, 2019
#15
  • Jul 2, 2019
  • #15
Well they have custom ones right there
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,720
214
Hillsborough county
Jul 2, 2019
#16
  • Jul 2, 2019
  • #16
springs will need to be updated to match the cam you plan to run. buy them at the same time. Shy away from the older letter cam from FRPP, you want a dual pattern cam.. no need to worry about EFI stuff so the cam can be more aggressive.. what are the plans for the car? we can base our suggestions better on that. Most guys will tell you to consider a custom cam from the likes of comp or FTI, but you can get ahold of summit and there tech guys can help you pick something out.
 
8

83RagTop5.0

Member
Jun 29, 2019
22
2
13
Seattle
Jul 2, 2019
#17
  • Jul 2, 2019
  • #17
My ultimate plans for the car is to just have get it running and make it clean. I just want it to be a reliable yet still slightly powerful summer cruising car for myself and the woman. I have aspirations to acquire an 85-86 Ttop and that will be the car I would like to do a full build on. So I figured this would be the perfect chance to understand the 302 a little more. My initial plans were to just rebuild the stock non roller block but after a little research realized that it wasn’t worth the headache so why not gain a little power and knowledge of roller blocks all at once. Basically I just want a 250hp vert to cruise and pop the clutch from time to time. When I get home today I’ll update the post with pictures of the car as well as some specs.
Meeting the guy with the explorer after work today as well. I’ll snag some engine bay and head pictures.
 
8

83RagTop5.0

Member
Jun 29, 2019
22
2
13
Seattle
Jul 2, 2019
#18
  • Jul 2, 2019
  • #18
Well I went check the explorer out. As expected 5.0 HO. But the engine bay is so clustered and it was pissing rain so I didn’t get any pictures. I did however get the VIN. Not sure if that’s going to help but figured I’d run it and see how those decoder sites work. I will be towing the explorer home Saturday. When I can find some time between work and the woman I will pull the engine out and sell the explorer to pick n pull. I’ve attached some pictures of my car as well to this post.
And I guess my ultimate plan for this build is to just have it be a summer car that never does over 80 but has low end torque to light them up with “more ease”.
 

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83RagTop5.0

Member
Jun 29, 2019
22
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Seattle
Jul 4, 2019
#19
  • Jul 4, 2019
  • #19
I have since decided to change my mind almost entirely. My buddy keeps bugging the hell out of my with his dumb ass comments and his automatic bmw. Drug his ass countless times in my 2000GT. Decided this cars gonna have to do the same, for the sake of shutting him up.
Should be getting the explorer tomorrow granted no bull happens. I’m going to attempt a full build on it. Still mainly going to be looking for the low to mid end range torque over top end speed. I will be swapping this build into a coupe car within the next couple years. I would like to be able to keep myself about 3k give or take for the entire build after acquiring the block.
In which direction should I be looking to go with this?
 
8

83RagTop5.0

Member
Jun 29, 2019
22
2
13
Seattle
Jul 4, 2019
#20
  • Jul 4, 2019
  • #20
I have since decided to change my mind almost entirely. My buddy keeps bugging the hell out of my with his dumb ass comments and his automatic bmw. Drug his ass countless times in my 2000GT. Decided this cars gonna have to do the same, for the sake of shutting him up.
Should be getting the explorer tomorrow granted no bull happens. I’m going to attempt a full build on it. Still mainly going to be looking for the low to mid end range torque over top end speed. I will be swapping this build into a coupe car within the next couple years. I would like to be able to keep myself about 3k give or take for the entire build after acquiring the block.
In which direction should I be looking to go with this?
 
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