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10-23-2011, 02:16 AM
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CC Member
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Join Date: Aug 2009
Location: Adelaide,
SA
Cobra Make, Engine: AP 289FIA 'English' spec.
Posts: 13,150
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Quote:
Originally Posted by roadrod2000
I have a HIPO 289 powered Unique FIA car with a 4.27 rear axle ratio and a ford motorsports T5. The camshaft is a solid lifter with .560/.512 I/E lift and 244/254 duration at .050. I just looked at a chart comparing RPMs at MPH for both my setup and the one proposed by XB-60 /Glen (3.07 rear and wide ratio toploader). What I find is that my 2nd, 3rd, and 4th gear are very close to the same (compounded ratio) as Glen’s 1st, 2nd, and 3rd , with that in mind this is what I experience driving the car; 1st gear is too low, I can easily get the car moving by starting in 2nd (starts on a hill might be a challenge though ) 2nd through 4th are well spaced and fun, but my jump from 4th to 5th is too much of an RPM drop, at 55 in 4th I’m at about 3000 rpm’s, the shift to 5th drops me to about 1900 and the engine is not happy there, so driving a winding mountain road is a battle between 4th and 5th . On the freeway at 70 I’m at 2400 rpm’s and that works fine for cruising but ideally I want to raise the rear ratio and drop the overdrive ratio so that 4th to 5th is closer. To summarize; the 3.07 /wide ratio toploader combo would probably work well with my car and for how I drive it, but on that hill I would want a slightly lower 1st.
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Good, thanks, I haven't had many (good) comments on my proposed gearing. It sounds like your 5th gear is a 0.62 overdrive, so your fourth - fifth split of 1.56 is a little different to my third - fourth split of 1.36
Having a high first gear - equivalent to your second gear - is OK, and even desirable. On both of my current cars I often start off in second gear if it's not uphill, and one of the cars, 35 years old, still has the clutch that it drove out of the factory with, so I'm easy enough on clutches even taking into account the second gear starts.
Cheers,
Glen
Last edited by xb-60; 10-23-2011 at 02:18 AM..
Reason: wanted to
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10-23-2011, 02:25 AM
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CC Member
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Join Date: Aug 2009
Location: Adelaide,
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Cobra Make, Engine: AP 289FIA 'English' spec.
Posts: 13,150
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Quote:
Originally Posted by undy
600 rpm idle, 1000 rpm cruise, tremendous off idle power, 7100 rpm rev limit & spins up faster than an aluminum rod destroked 283... sounds like he needs a LS7...
It CAN be done... (given enough $$)
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A what? What's that?
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10-23-2011, 02:35 AM
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CC Member
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Join Date: Aug 2009
Location: Adelaide,
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Cobra Make, Engine: AP 289FIA 'English' spec.
Posts: 13,150
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Quote:
Originally Posted by blykins
Z,
It's not all about how much power you make down low, it's about how easy the engine will run and cruise down that low too.
From his description, he's wanting an engine that will cruise around right off of idle but then make peak horsepower at 7000.
There is a difference between making *some* power at 7000 and making *peak* power at 7000. If you just make *some* power at 7000 and the peak is much lower, then there's no use at all in straining the engine and putting undue stress on it at that rpms. Just because you can see 7000 on a tach doesn't mean that you haven't lost 50-75 hp by the time you get there.
I've given many concrete options for him in previous posts. And again, I'm not trying to be negative, but I'm trying to offer advice that comes from experience.
I agree with you 100%. I think it would be more worthwhile to put the peak down lower, say 6000 rpm, then see how the car behaves that way. If it's not suitable, then parts can be swapped.
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Max revs, or change up revs, or 7000, and max power at ....whatever...6500?....
And at the bottom end, able to take 3.08 gearing at 1500prm ideally. That doesn't mean real grunt at 1500, it means at steady speed, level ground, no driveline snatching. If acceleration required, or slight hill encountered, the a change down to third. Oh, and the weight I'm anticipating is 2350lb
Thanks for your continuing interest guys, I though this one might have died a while ago. I AM actually learning stuff here. Appreciated.
Cheers,
Glen
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10-23-2011, 04:06 AM
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CC Member
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Join Date: Aug 2003
Location: Hockley, Tx./Northwest Houston,
TX
Cobra Make, Engine: B&B 427 body and building my own chassis. Modifying a Jaguar front irs and a Dana 44 in a 4 bar set up in the rear. 351W/408 Stroker I am building myself, top loader 4 speed..Dana 44 rear w/ 4 link
Posts: 85
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I am currently going to an automotive machinists school that specializes in teaching the special knowledge and techniques required for building racing engines exclusively. I am 100% DAV/Disabled American Veteran from Vietnam and it is a childhood dream of mine..the school is the only one of it's type in the USA recognized by the Veteran's Administration Vocational Rehab program...having said all that. We have 3 different drag cars that we campaign and one was national champ/record holder in it's class 2 years ago. 158mph@8.4 sec in 1/4 mile. 401 cubic inch Ford 351W stroker in 1995 Mustang, 3400 pounds with 10 inch tires. All natural aspirated with Braswell 4bbl carb, no nitrous, no turbo, no supercharger, 110 octane race gasoline, 4:11 gears...It IS A RACE ENGINE!!
935 Hp, 840 lb/ft torque and spins 9800 rpm, Ferrea titanium valves, solid roller set-up with 345lb seat closed and about 550lb open, 3 coil beehive set-up, Jessel valve train set-up and timing mechanism. trick 3 plate clutch with gram weights, etc. Clutch was $8500...Total cost of parts alone for the engine was in excess of $125,000! Plus machining costs...Piston rings (Just 2 for each piston, not 3) were over $900! LOL
As the owner of the school explained to me (I used to be a motorcycle tuner/mechanic in the 1970s for a Class C junior flat tracker) and knew nothing about particulars of drag racing... You want your engine power(HP) still climbing/pulling as you cross the finish line! And I said, But what about torque? he said torque is for twisting bolts! LOL..Still not sure if I really agree with him on that one, but he does have 40 years of racing under his belt in many forms of racing including 3 years on a NASCAR pit crew (Donny Allison) He even has his original '69 Z-28 street racer with only 9300 original miles and his wife races too!...Anyway the gentleman needs to realize that an engine is designed to perform in certain rev range and to perform certain types of work....3.07 gearing is like a touring car gear and he still wants it to "not run out of steam", at 6000rpm? I think he needs to decide if he wants to go touring or stop light acceleration, drag race, or auto cross? I've discovered if you put it to a customer in those approximate terms, you as an engine builder can then make sensible suggestions as to the type of engine and drive train he NEEDS. I think he needs a 342 stroker, around 400hp, hydraulic roller and maybe 3.86-4.11 gears and a 5 or 6 speed with over drive, and 8 inch tires on the rear...Oh, and don't forget the racer's rule:...How fast do you want to go?...How much money do you have? LOL Geez it is late and I am rambling way too much! LOL
__________________
Semper Fi!
Bigfoot.
Mike Co. 3/5
1st Marine Division
"The Nam", 1967
Grunt infantry
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10-23-2011, 05:30 AM
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CC Member
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Join Date: Dec 2001
Location: Louisville,
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Cobra Make, Engine: I'm Cobra-less!
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Quote:
Originally Posted by xb-60
Max revs, or change up revs, or 7000, and max power at ....whatever...6500?....
And at the bottom end, able to take 3.08 gearing at 1500prm ideally. That doesn't mean real grunt at 1500, it means at steady speed, level ground, no driveline snatching. If acceleration required, or slight hill encountered, the a change down to third. Oh, and the weight I'm anticipating is 2350lb
Thanks for your continuing interest guys, I though this one might have died a while ago. I AM actually learning stuff here. Appreciated.
Cheers,
Glen
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I think I know what you mean by driveline snatching....we call it "bucking". You would have that with an engine cammed to make horsepower at 7000 while trying to cruise at an off-idle rpm.
Ok guys.....listen up.
I'm not saying that it's not possible to make horsepower at higher rpms. I'm not saying that torque rules the roost.
I am saying that with this particular car, this particular transmission, and this particular rearend, an engine that peaks at 7000 isn't a good match.
If you'll look at some of the engines that I build for myself (when I have time), you'll see that I like them a little on the revvy side. Most of my engines peak at 6400-6500. I like that. HOWEVER, I don't pair them up with rearend gears that will make them total turds... I normally have at least 3.70-4.30 gears. This goes for my Mustang, my Cobra, etc.
I've also owned some of the modular 4.6L engines that Olddog was talking about. Sean Hyland doesn't need large durations and large lifts because the engines are very small. The 4.6L started out as only 281 cubic inches! You don't need 350 cfm flow numbers to support that. However, these engines made decent horsepower, but they had no torque. My '02 Mustang with the 4.6L was a complete turd at lower rpms, even with 260hp and 305 lb-ft of torque. It received a 4.10 rearend. My dad has a '97 Mustang Cobra with the DOHC 4.6L. It was a turd at lower rpms with the 3.27 rearend. It too received a 4.10 gear so that it would have some lowend grunt and pull to 7000. The 4.6's will also rev easier because they have no pushrods....everything is overhead, so you don't have to worry about valve float, etc. They also have extremely small bores and strokes so the rotating assembly is light. Not really an apples to apples comparison here.
That is what I'm getting at.
You will not find a 302 that makes power at both extreme ends of the powerband. That's not the way engines operate.
So if you want to go that route, you need to make sure that the rest of the car's combination will help you in the best way that you can.
Also, if you have an ERA FIA car, you will find that it will weigh closer to 2600 lbs, plus driver, plus fuel.
Last edited by blykins; 10-23-2011 at 05:43 AM..
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10-23-2011, 05:56 AM
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Drive train lugging and it hurts the motor
Blykins Brent You can lead a horse to water but will not drink. Let it go. This guys needs to run either a 6 speed trans, change the rearend ratio, build a bigger motor or go fishing. 10 pages of info from guys that have tried the same thing. If he want to have the motor not lug at 1,500 rpms he will need a heavier flywheel and dampener to absorb the firing of the motor under this kind of load. This will damage the motor over time, something will break. He want to turn 7,000 rpms with a stock block, without it being filled in the coolant passages for strength, no main cap support or 4 bolt main. Cast crank pistons and off the self rods. Good luck, it will be a short fairy tale. I REALLY hope that Glen or his friend in the pass seat don't get hurt from flying debrie when this thing breaks. Bell housing only partial protect from flywheel, they do nothing for engine parts. My thinking is a mazda rotary motor with 3 rotors and a turbo. 600 hp and will lug along too. I'm done Rick L.
Last edited by RICK LAKE; 10-23-2011 at 06:00 AM..
Reason: can't spell at 5:30 am
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10-23-2011, 06:22 AM
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CC Member
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Join Date: Jul 2005
Location: Virginia Beach, Va & Port Charlotte, Fl.,
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Quote:
Originally Posted by xb-60
A what? What's that?
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Sorry, it's a Chevy Z06, my daily beater. 10.80 @ 130 in street trim, 509 RWHP, 22 average mpg, combined w/ 28mpg on trips. My grandma could drive the thing. It's 427ci though... Ask our friends across the pond about the engine. Unfortunately, in the states it's Cobra blasphemy
Until the Coyote 5.0 came around Ford had lost it's ability to make any normally aspirated horsepower with the intro of their mod motors.
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10-23-2011, 07:44 AM
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CC Member
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Join Date: Aug 2003
Location: Hockley, Tx./Northwest Houston,
TX
Cobra Make, Engine: B&B 427 body and building my own chassis. Modifying a Jaguar front irs and a Dana 44 in a 4 bar set up in the rear. 351W/408 Stroker I am building myself, top loader 4 speed..Dana 44 rear w/ 4 link
Posts: 85
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LOL, I lived and worked in England for 6 years back in the early to mid 1990s and that was what turned me onto the whole kit car scene. While I was there, I visited every Cobra replica manufacturer there was and the 'standard' set-up was the all aluminum Rover V-8 based on the Olds V-8 that GM sold the rights to back in early 1960s or if one wanted to go "big" they stuffed a Chevy 350 in their Cobra! of course if they really wanted to have the 'bee's knees', they stuffed a Jag V-12 in their Cobra!...Hmm..Maybe we should all just put in Chevy LS engines and forget about it? It is a lot better designed engine and has the same firing order as the 351W, lighter, stronger, and can make practically 600hp out of the box with a cam change! WTF! over!??
LOL
__________________
Semper Fi!
Bigfoot.
Mike Co. 3/5
1st Marine Division
"The Nam", 1967
Grunt infantry
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10-23-2011, 09:00 AM
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10-23-2011, 10:52 AM
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Join Date: May 2006
Location: St. Louisville,
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Cobra Make, Engine: A&C 67 427 cobra SB
Posts: 2,445
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Quote:
Originally Posted by xb-60
Good point olddog. There's an article I've come across a couple of times 400 HP 302 ci AFR 165 cc(Stock Cam) about obtaining over 400bhp from a SBF 302 while retaining the stock factory hydraulic roller cam, main changes being heads (to AFR165), by using higher ratio roller rockers, and headers/extractors. Main point is that it uses the stock factory cam. Does that mean that it would retain some manners at the bottom end while delivering at the top end (with the power graph still steep at 6200rpm)?
OK, I've said that my preference is to stay with CI heads for authenticity, but this seems to me to indicate that I could easily stay with a 302
Cheers,
Glen
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One note of caution, magazines dyno numbers have often seemed too good to be true. After all they are marketing magazines, with advertisers paying the bills. The advertisers usually supply the parts.
If you will note on their chart the Hp is still climbing quite steep at the 6200 rpm when they stopped. The Hp had not peaked, so why did they top? Valve control issues? Were they afraid the bottom end would let loose? We they weary the stock block might split in two (in a few dyno sweeps, probably not)?
Now you are wanting to make power to 8000 rpm. I assume that means a peak at around 7500 or a little less. As good as the 165cc AFR heads are, they will not flow enough to do that. You would need at least the 185cc AFR heads. This mean low port velocity at lower rpms and less torque down low.
To keep the engine from wanting to buck cruising at 1500 rpm, you will have to keep the valve overlap very low, similar to a factory stock cam. You will need higher lift to get the flow at top end, and you are going to have to lengthen the duration out to make power up top. The trick is going to be, how do I do this without killing the bottom end? My theory, which is counter to what most experts will tell you, is to keep the duration under 230 and go with better flowing heads. I feel that will give you a long flat torque curve. You will still end up with low torque at low rpm because of the port velocity, but the milder cam will not want to buck and hop off idle. To still flow enough air to peak the Hp at 7500 rpm is going to require very good heads, that most experts will tell you are way too big for a 302. Now remember this is my theory that is untested. I could be very wrong, and probably am wrong. However, the article you provided tends to support my theory.
Last edited by olddog; 10-23-2011 at 10:55 AM..
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10-23-2011, 11:22 AM
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Theoretically that's the best way to do it. However, it would be extremely difficult to add that much flow without adding an excessive amount of port volume....which slows the velocity down, hurts throttle response, bottom end power, etc. Think Boss 302.
I also don't think you're going to get there without at least 244-248° of cam duration....even with 185-205cc ports and 300+ cfm flow numbers.
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10-23-2011, 11:26 AM
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If you will note on their chart the Hp is still climbing quite steep at the 6200 rpm when they stopped
I think if they could have shown the curve up to 7K they would have. The whole point of the article is showing what you can ring out of a stock cammed 302. Seems to me stopping at 6200 is suspect and agree that what you propose probably played into that decision.
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10-23-2011, 12:59 PM
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Join Date: May 2006
Location: St. Louisville,
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Cobra Make, Engine: A&C 67 427 cobra SB
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I was trying to come up with a longer rod 302, for a better rod ratio at high rpm. I’m not sure it is a good idea. Thought I would put it out as food for thought. The 302 1.7 rod ratio is not all that bad to begin with, but a 289 has a 1.8 rod ratio. We know race teams were spinning cast iron crank 289 to 8,000 rpm. I cannot say a longer rod would be better for high rpm, but it is typically assumed to be. This may be a rob Peter to pay Paul game, as the weight increase of the longer rod may increase the stresses more than the rod ratio improvement reduces them.
I calculated the piston pin compression height for a 347 stroker piston to be 1.090” by assuming the deck height clearance to be the same as a 302, which may or may not be true.
Now if you used the 347 stroker piston in a 302, it would allow a longer rod. A sb Chevy 400 rod is 5.565 long. That rod and piston combination would give a 0.051 deck height clearance compared to the 302 factory deck height clearance of 0.016 inch. Not ideal but perhaps a pop up piston would get a decent compression ratio. That would give a 1.855 rod ratio compared to a factory 302 rod ration of 1.7.
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10-24-2011, 01:05 AM
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CC Member
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Join Date: Aug 2009
Location: Adelaide,
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Cobra Make, Engine: AP 289FIA 'English' spec.
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Quote:
Originally Posted by RICK LAKE
Blykins Brent You can lead a horse to water but will not drink. Let it go. This guys needs to run either a 6 speed trans, change the rearend ratio, build a bigger motor or go fishing. 10 pages of info from guys that have tried the same thing. If he want to have the motor not lug at 1,500 rpms he will need a heavier flywheel and dampener to absorb the firing of the motor under this kind of load. This will damage the motor over time, something will break. He want to turn 7,000 rpms with a stock block, without it being filled in the coolant passages for strength, no main cap support or 4 bolt main. Cast crank pistons and off the self rods. Good luck, it will be a short fairy tale. I REALLY hope that Glen or his friend in the pass seat don't get hurt from flying debrie when this thing breaks. Bell housing only partial protect from flywheel, they do nothing for engine parts. My thinking is a mazda rotary motor with 3 rotors and a turbo. 600 hp and will lug along too. I'm done Rick L.
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What I asked in the OP was for information about lifters. Post #6 asked me for more information.
Typically if I don't understand something, I ask questions.
Cheers,
Glen
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10-24-2011, 02:55 AM
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XB,
If you can get Modified Mustangs & Ford magazine over there, pick up the issue that is getting ready to come out.
I have an article in there, using a Boss 529 engine, that explains a lot about picking the engine parts to match the system as a whole. It goes through a lot of parts selection, descriptions, etc.
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10-24-2011, 03:46 AM
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CC Member
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Join Date: Aug 2009
Location: Adelaide,
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Cobra Make, Engine: AP 289FIA 'English' spec.
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Quote:
Originally Posted by blykins
XB,
If you can get Modified Mustangs & Ford magazine over there, pick up the issue that is getting ready to come out.
I have an article in there, using a Boss 529 engine, that explains a lot about picking the engine parts to match the system as a whole. It goes through a lot of parts selection, descriptions, etc.
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Thanks Brent. Yes I can get it here. I'll look out for it
Cheers,
Glen
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10-24-2011, 04:24 AM
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What you asked for is about building a motor with BAD SPEC
xb-60 Glen There is no issues with asking questions about ANYTHING. The problem starts when 5 different guys try and point out a BETTER way and cheaper in the long run to build a motor. You want to stay with a 289, FINE. You can stroke it to a 331 WITHOUT anyone knowing it's that big. You want BOTH WORLDS. Been there along with others here and tryed it. This motor will tear it's guts out trying to meet both a idle of 700 rpms and a 7,000 rpm red line. All the crap you read in the RAG MAGS is alot of just that CRAP. The problem is they can get these motors to do what's in the article. They just donot tell you how long these motor last on the street. Simple answer to this, even with good parts, EVERY part has a life limit. Your motor will have crazy high piston speed, a cast crank with a 6,700 safe limit. I hope the pistons are forged. If these guys in the article are so great why are they not in the engine masters. Go back the last 7 years and look at who is who. There are about 5 master mashinist I have talked to and said they don't have the time or money for this game. This is FE motor guys, Gessford machine and Kuntz are 2 to start. Thanks to Barry R. he has relite the fire for the FE motors and done really well. The caught is this, his motors can be bolted in any car and are drivable for thousands of miles. Some of the other motors are just that dyno motors for an rpm range that live for maybe 20-50 hour total and start to come apart. Just like a Nascar motor, 1 race and in the bucket. I wish you luck with your build. Thereis not such thing as a stupid question. i spent 3 years asking them myself before building an FE motor from the east to the west coast. Learned alot and meet some great people who are alive but some have pass. MY issue is that they left this world without writing down any of this info to pass on to future generations of builder, buyers and owners. I know they don't want to give all there secerts away and do not. Over time everything is found out. Again good luck, Have a Fosters for me. Rick L.
Last edited by RICK LAKE; 10-24-2011 at 04:28 AM..
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10-24-2011, 07:32 AM
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Quote:
Originally Posted by RICK LAKE
".............. He want to turn 7,000 rpms with a stock block, without it being filled in the coolant passages for strength, no main cap support or 4 bolt main. Cast crank pistons and off the self rods. Good luck, it will be a short fairy tale. ..........."
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Quote:
Originally Posted by RICK LAKE
"............... This motor will tear it's guts out trying to meet both a idle of 700 rpms and a 7,000 rpm red line. ......"
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starting with your assertion above, I can't figure out how thousands of 289 Hi-Po's have been hitting 7000 rpm regularly over the past 45 years ? They don't have any of the features you list above. (full disclosure: my engine had no trouble keeping it's "guts" together with the original cast pistons for 35 years, but I changed to +0.020" forged pistons anyway about 10 years ago.).
Long live the fairy tale.
p.s. Can't meet the 700 rpm idle mark though, 800 is about as low as is reliable, ymmv.
Z.
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Last edited by zrayr; 10-25-2011 at 08:15 AM..
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10-24-2011, 06:43 PM
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CC Member
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Join Date: May 2006
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Cobra Make, Engine: A&C 67 427 cobra SB
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Well I very much disagree with the planned gearing, and I personally wouldn't build a 302 for 8000 rpm. With that said, a 8000 rpm 302 is not all that radical. The SB Ford, likely the shortest deck height of all push rod V-8, is well suited to be a high rpm engine. The short deck gives the lightest of valve trains and the lightest rod. Your starting out with an engine that needs the fewest modifications to go more rpm. The only thing lacking is the block and rods. I would recommend good aftermarket rods and block. I would internally (zero) balance it too.
Let's put some things into perspective. Guys are spinning 4.25" stroke FE 6000 rpm. A 3" stroke has to spin 8500 rpm to achieve the same mean piston speed. Then we are talking a 4" bore compared to a 4.23" bore -- a much lighter piston. Now a 6.488" rod length verse a 5.090" (I don't know what the FE stroker rod is). Certainly the FE stroker has a much worse rod ratio. So the FE is turning higher piston speeds with a much heavier piston, rod, and wrist pin, with a worse rod ratio. I say a FE stroker turning 6000 rpm is a much more radical engine than a 302 turning 8000 rpm, from a rotating assembly point of view.
Now the FE has bigger, longer valves and springs. A longer push rod, and larger rocker, too. I do not have the weights nor the formulas to calculate valve geometry. However my gut tells me that 8000 rpm on the 302 will only be a little more challenge than 6000 rpm on the FE, not a huge difference.
I have spun 327 Chevy to 8000 rpm, with a stock bottom end, and aluminum roller rockers. Springs that came in the cam kit with solid lifters. I ran the crap out of it for a year with no problems. Maybe I was lucky. I sure wouldn't do it today. But the point is 8000 rpm on a 302 is not some insane, radical, or stupid idea. I believe NASCAR was turning FE engines 7000-8000 rpm back in the day.
Anyone know what Shelby and the others were turning the 289 in the races with the original SB Cobra? I expect they were getting every bit of 450 hp and turning them 8000 rpm or more.
Last edited by olddog; 10-24-2011 at 06:51 PM..
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10-25-2011, 02:41 AM
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Join Date: Aug 2009
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So how can a guy like me who doesn’t really know what he’s talking about make sense of all this?
Why are the pro-stroker and the non-stroker (pro-revver?) camps so far apart?
Cheers,
Glen
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