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Discussion Starter #1
i am getting ready to rebuild. i don't have enough money for my 427 windsor yet. i am trying to stay simple and not spend that much money. i was thinking of going with the 306 long rod or either just a 306. how much of a difference will i be able to see with the long rod.

thanks for the info
 

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I'd stay with the stock length rods, I'm not caught up in the rod ratio bandwagon (as long as its 1.50 or better) and the 302 has a decent ratio to begin with.

Get the stock rods reconned with new ARP bolts (the cheap ones they offer) and use shelf stock for your pistons. Or use a low cost set of SCAT or Eagle I-beams

A long rod 306 shortblock (uses a custom piston) costs about the same as a 347 shortblock. The 347 will make an easy 40 more horsepower over any 306.

But if rod ratio is what your after...

The ultimate small Ford is to take a 2.87 stroke 289 crank and cut it down to a 2.80 stroke with a 2.1 journal. This way you can stuff a 5.7 Chevy rod in there and get a 2.036 rod ratio ( this can use an off the shelf SRP 347 piston, these have a Chevy pin diameter and a 1.1 pin height). I actually want to build one of these some day, talk about a 10,000 rpm monster. :evil:
 

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Discussion Starter #3
thanks for the info anyone else? i was looking at getting the dss kit with the 5.4 rods which is $800 how much of a difference does the long rod make over the stock as far as horsepower or does it just rev faster
 

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If the rods are not superlight, you are swinging the extra weight from the extra length. This will likely counter any benefits from the length. I think the long-rod benefits come in at high rpms anyway. If you are not racing, you are probably better off keeping the stock length.
 

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not just high rpm racing you wil see more power due to the fact that thew psitons floats at TDC for longer
 

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onesillynotch said:
not just high rpm racing you wil see more power due to the fact that thew psitons floats at TDC for longer
i agree with onesillynotch on this one, I used a 5.155 with a 40 over bore and the motor felt it had alot more torque and pulled really hard on the top end, compared to my 306 and 5.090 btw this was a blower car.
 

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Go with a stock rebuild if your planning on building a stroker in the near future, Building a long rod 302 isnt going to be real cheap. I would save the extra cost of the long rod engine and put that money into the 427 fund.
 

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From what I've learned about rod ratios and the whole longer rod thing the main difference is that with a longer rod you can run a shorter comp height piston that is lighter and will take some of the loads off of the connecting rod. The piston dwell and change in acceleration doesn't seem to be a concern to the engine builders I have been learning from. Their idea seems to be to always use the longest rod practical for your application as that will allow a lighter piston to be used.
 

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not just high rpm racing you wil see more power due to the fact that thew psitons floats at TDC for longer- onesillynotch

From what I've learned about rod ratios and the whole longer rod thing the main difference is that with a longer rod you can run a shorter comp height piston that is lighter and will take some of the loads off of the connecting rod. The piston dwell and change in acceleration doesn't seem to be a concern to the engine builders I have been learning from. Their idea seems to be to always use the longest rod practical for your application as that will allow a lighter piston to be used.-Dano73327

Well, with a street car you are also concerned with that area spent below about 4k-4500, where that nice long rod also reduces cylinder filling due to reduced intake velocity. The long rod means that over a larger percentage of every stroke, that piston is traveling slower, both up and down, meaning it pulls less mixture into the cylinder at lower RPMs, and also compresses it less before the fire is lit. This kinda biases a really long rod to a high-rpm racing motor, and a short rod into the realm of us normal people (i.e. under 6500). FPS told me that they had experimented with all the rod lengths available for a 302, and none were really worth the money, most of them cost low-end and midrange to a significant amount, while only being 3-5HP stronger on the top end. They told me the only cost effective swap was sticking the 5.155 289 rods in, and that was only if you had a set. I mean, really when you look at it, it goes like this. Chrysler has by FAR the biggest rod/stroke ratios of the Big 3, and Chevy generally has the shortest rod/stroke ratios, with almost all Ford motors in the middle. Doesn't really seem to affect them the way the factory makes em, does it? That's what confuses me, Chevys and Fords are on the low end and always make better motors, and yet everyone is trying to achieve Mopar rod/stroke combos. Oh well, when my combo is together I'll dig this thread up to let you guys know. Thanks.

Chris
 

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Discussion Starter #14
thanks guys for all the info i think i am jus going to go with the stock stroke


thanks to all with imput
 

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The piston still travels the same distance in both a short and long rod engine with the same stroke. The biggest advantages have been discussed such as a lighter piston and piston dwell time at TDC. The piston acceleration rates are slowed which helps cylinder filling if your using a congested induction system. Now to the other side of the fence, A shorter rod will have less dwell time at TDC and piston acceleration rates are much higher. These 2 factors are also advantageous due to less of a chance for detonation to occur.
 
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