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Discussion Starter #1
Hi. I am new to building engines so this forum is great.
I do not have a Mustang but I have a 5.0 302 that according to the block # came out of a 87' truck. The motor is stock and the rods have the 5/16 bolts that everyone talks about. My question is, will those bolts hold up to 300 hp? I plan on using aftermarket heads with about a 10:to 1 comp ratio. I am on a major budget and dont want to have to buy ARP bolts and risize the rods if I dont have to. Any help is GREATLY app. (P.S. motor is going in a 95 Ford Ranger in the near future but since its a 5.0 Im glad I can talk to you guys)

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Depends on your use. 300hp from a 302 isn't much; stock parts can easily handle those power levels.

RPM's put more stress on the rod bolts that power level does. If you're going to run a solid cam with rpm's consistantly > 6,000, then upgrade the bolts. If not, the stockers will be fine.

Your current bolts are 13 years old. If they have a lot of miles on them, get new ones.
 

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Funny you should ask...

I just snapped a puny stock Ford rod bolt assembling my bottom end about a week ago. I'd say bite the bullet and get the ARP's, they are like $70 shipped from summit and have a machine shop press them in and resize the rods.

I am a college student and on a wicked budget too. But after al lthe time and effort you put into the motor, it would suck to have a rod bolt let go turning 4500 and destroy everything you've built. Trust me, I cringed at the thought of going to the machine shop again, But now I know that there is not way that those rod bolts will break.

That's just my opinion
 

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Discussion Starter #4
many questions

Do you see any problems with my plans of the following. ( My goal is to have a daily driver that sounds fun and has around 300 - 350 hp.)
The block and lower end are stock 5.0 roller block OEM. I plan on using a Comps "Thumper" cam ( for the cool sound and some upgrade). It is 0.531 lift on Intake 0.515 exhaust, 227 Duration Intake/ 241 exhaust roller cam. Saving for the AFR 185 Alum heads. They are 58cc chambers. I am not sure what the compression ratio would be with my stock rod/crank and pistons which are slightly dished. I can not find much info on them. I currently have the crappy E6 heads that everyone seems to hate ha.
I have a Elderbrock Performer dual plane intake and plan on a 600 cfm carb as I hear people say dont go to big.
Finishing it with hugger type of headers as its a tight fit.
I do not plan on drag racing, just somthing fun on the road and sound kinda mean.
I have a manule trans 5 speed in the Ranger now and want to stay 5 speed if I can. as for the rear end, it is stock and I have no idea what gears I should use.

Anyways, thats whats in my head so if you see anything that looks off it would be great to hear it before i break open my piggy bank. The heads are my big cost, but I dont know if I can get heads that will flow well and support the high lift of the cam without still spending a lot in the machine shop if i get somthing used. If its going to cost $800 + id rather keep saving for the new heads.

Thanks for any input.
 

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Discussion Starter #5
Thanks for the 5/16 bolt advice. I guess I will suck it up and change them. Some people talk about going up one size if they change them. I guess I will ask the machine shop guy.
 

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I didn't go up a size, the bolts are good until around 200,000 PSI, which is a pressure you will never ever ever reach. The rod will break before the bolts do. I'm using my stock bottom end with the exception of KB FHR forged slugs (I had an '86 with flat tops so I had to swap hte pistons to run a cam)

The combo looks prety good for a street car. From waht I hear those AFR heads are the best out there. I'm sure someone will chime in with theirr opinions has well.
 

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Discussion Starter #7
Last question ( of the day)... Does anyone know the approx compression ratio and CC of my heads? Its the E6 heads with stock pistons that are very slightly dished. Stock rods as well.
its from a 1987 302 5.0 out of a truck per the engine code.

I am also concerned that i will need new pistons since I really want the Comp Cams "Thumper" type of cam. Intake and Exuast lifts are just over .500 on that cam....

Thanks for the help everyone.

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here is a link for a compression ratio calculator :

Engine Compression Ratio (CR) Calculator

I can't say exactly but I'd say anywhere between 8.8:1 to 9.2:1.

I don't think there will be any problems with that cam, but the people from comp are usually very helpful, I would give them a call and explain your situation and i'm sure they'll be able to guide you from there :bigthumbsup
 

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Last question ( of the day)... Does anyone know the approx compression ratio and CC of my heads? Its the E6 heads with stock pistons that are very slightly dished. Stock rods as well.
its from a 1987 302 5.0 out of a truck per the engine code.

I am also concerned that i will need new pistons since I really want the Comp Cams "Thumper" type of cam. Intake and Exuast lifts are just over .500 on that cam....

Thanks for the help everyone.

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Investing in am aftermarket camshaft and using E6 heads is an absolute waste of money. It doesn't matter how long the valves get held open or how far they get opened, those heads cannot flow. All you will wind up doing is getting too long of a duration, reducing cylinder pressure, and thus losing power.
Before you even think about a cam you need to get some respectable heads.
I'm not trying to be abrasive, I'm just trying to save you some money and disappointment.
 

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you could prob pick up some GT-40's for cheap at a local pick and pull...

Good call YLDPONY, That never even crossed my mind
 
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