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Discussion Starter #1
Witch is stronger a 68,302 bored .030 or a 5.0 bored .030? As far as high rpm HP abuse. Also witch crank is stronger 5.0 or 302.
I know the 5.0 is a roller block but you can buy a roller set up but can you buy strength.

I have heard that the older 302 stuff was a little stronger is this true?
 

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if you are asking whitch one is stronger because you think you might be close to the power level that oner can take it might be a good idea to look in to a 302HD or mayeb an R302 block
 

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I under the impression that the 5.0 were stronger and they had a little bit of nickel in them.

I may be wrong.
 

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A 5.0 is a 302, how strong the block is will depend on where the block was cast and how much nickel content is in the block.
 

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Discussion Starter #7
OK you have a 68-302 and a 89-5.0 Witch one is stronger for high rpm HP. I have no idea how much nickel is in them I just want to use the stronger of the two. I have both in my shop and want to use the stronger of the two. Let's not make this a chemistry(sp) lesson.
 

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The older block is definitely heavier. The newer 5.0 blocks and cranks are extensively lightened, and have a bad habit of cracking under SEVERE usage. Their 50oz-in balance, compared to the 28 oz-in of the older engine is inferior. The older 28 ounce balance is better for higher rpm.

The engine block in my mustang is a 68', and has survived REPEATED 7000rpm blasts and has had dozens of nitrous bottles emptied through it 200hp at a time. It also has a factory cast iron crank and 289 rods. It has held up well through 9 years of hard running.

I'd use the older one. As long as it isn't abused by running it into detonation, it will provide a long service life.


Check out the websites below for detailed specs on the engine.

Good Luck!
 

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I think the old block has a slight edge but I don't think its an issue unless you're putting out some very serious horsepower.Don't forget about the newer blocks roller cam, lots of guys change to the newer block for that reason alone.
 

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Just weigh the 2 blocks. That will give you your answer. The older 302 will be heavier and therefore stronger. More material in the main cap and oil pan rail area.
Ford took some material out of the Roller cam blocks to save weight for improved gas milage. I'd go with the older block if your going to make over say 350 HP. Other than that either block would due.
 

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400hp? at the crank or wheels?
how are you going to get to that point?

if your goals are 400hp, and its not going to be revved above 6000-6500 ever, stay with the lighter e-7. you dont need a small base circle cam to retro in a roller, or 400 dollar lifter that keep you from pulling the cam unless you remove the heads etc...but if you want this 400hp at 7000 rpm, and its going to spend time at that rpm, go with the older block and have the crank zero balanced!
neither of these blocks is up to hardcore racing like endurance, but thay can live at that power level drag racing at 1/4 mile at a time for years and years.
 

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Discussion Starter #14
I am going to be twisting it to 7500 plus. It will only see the track so I am open for combo's.

Here is my combo.

1968 302 block decked to -.010
76 302 crank
KB 116 pistons .030
351W heads 1.94 1.60 major port job with push rod holes filled and the port entrance straightened valves UN-shrouded cc'ed to 63cc's I should have them done as soon as my flow bench is working.
Crane Roller Rockers
Scat I-beam rods
Gear drive the noisy ones
Everything to be balanced just trying to make up my mind on witch crank to use.
Windage tray
The cam is still open for recommendations. Will use the springs that would be recommended for the cam.
Looking for a Victor-Jr


What do you mean by 0 balance?

I have all these parts just laying around and thought I would throw it together and run it in my 544 for the upcoming season. Still building the 393 Clevor.
 

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Looking at your whole combo (10 to 1 compression, ported factory heads, factory crank, stock block, etc.) I'd go with a solid lifter flat tappet cam with around 238-244 degrees of intake duration @ 0.050" and slightly more on the exhaust. I'd have it ground on a 106-108 lobe seperation (no bottle) or 110 if it's going to be a bottled ride.

This will spin the engine up to around 7000 rpm, with the major power coming on around 4-4.5k rpm. The heads won't allow the engine to efficiently spin any higher than this. The engine in my mustang has slightly more compression (289 heads) with a 236/248 solid cam and buzzes the tach up to a 6800rpm redline with no problem. My car weighs 3300lb with me in it and ran a 7.48 in the 1/8 with no bottle, 6.74 with it.... using a toploader 4-speed.

Check the web pages in my sig for more detailed info on the combination. It's very similar to what you've got planned.

Good Luck!
_________________
Mike Burch, 66 mustang real street
302 4-speed 289 heads, 10.63 @ 129.3
http://www.geocities.com/carbedstangs/cmml_mburch.html
http://www.fortunecity.com/silverstone/healey/367

<font size=-1>[ This Message was edited by: n2omike on 2/11/02 1:16am ]</font>
 

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well i think you ought to not spend a grand on those heads, and get cheaper set of better flowing heads, say tfs.
anyhoo, i woulnd spin any sbf engine that high regularly, unless you have the ability to switch blocks often.
0 balaning will cut down on the harmonics a bit, and if done properly, with a very good balancer (ie. fluidampr or ati) might actually last a while. with a 28oz imbalance it would be marginal up that high. others have done it, but for how long?
another thing, its not nearly required to spin the motor that high to get the power your looking for. especially if you go with a 331 or a 347, you could easily get away with about 6500 or less.
i know the attraction tho, i still want to build an 85000-9500 rpm 300" sbf for kicks, but a stock block aint gonna do it, and i cannot afford an r block....
 

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Discussion Starter #17
I would never spend a grand on any head. I have done all the work to the heads myself and I have a test head that I am working on but I have to Finnish the flow bench to complete my work. I'm not going at this with my eyes closed. I am trying different port work one step at a time with flow numbers to show if I'm doing the right things to it and to find out what I shouldn't do. For example I will do some work to the short turn radius of one intake port only. Then I will flow the head to see how much I gained or lost. If I lost flow due to the work I did I will try a different profile for that area on the next port in the test head. So I have 4 chances to get the short turn radius the best I can. Then move on to the next area and see what happens.

I know this is going to take awhile but in my world it's all good info for my brain. I'll keep you all up to date on the bench. I have all of the parts to get it working I'm now waiting for the machine shop to make the cylinder bores and orifice plates and to get my buddy back over to Finnish the cabinet. Got pics of the bench from the beginning I might even make a web page about it.

just how far can you turn a 302 that's balanced with scat I-beam rods. Or should I just put a 460 in it and sell all my 302 parts.
 

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I am running a 68 302 with a retrofit hydralic roller cam. 230'@.050 with .544 lift. TFS heads and a balanced assembly, deck block, forged TFS pistons...... the list goes on and on. I run nitrous (150HP shot), with a 3000 stall and 3.70 gears in a 68 coupe, every weekend, 1/4 mile at a time, with out a single problem. Love the combination Iv'e got and I think I can squeeze a couple of more tenths out of it with the proper tuning. Point is, run the 302 with the retrofit roller and have the best of both worlds....
ET 12.4 @108MPH.....
 
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