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| Need help with block identification -- joey, 04/25/2003
i have a block i cannot identify. its head casting # is c7ae-a. the block is marked "49dif"
[Post relocated by Admin.] |
| | Casting numbers on the heads won't help. -- Royce Peterson, 04/26/2003
The head casting C7AE-A was common on any 1967 FE. Could be 352, 390, 410 or 428. Parts often get swapped around over the years too so it won't help identify the block in any way.
FE block casting numbers are not a valid way to identify them either. You can find out when it was cast by looking at the date code cast into the block right next to the oil filter adapter. The casting number on the passenger side of the block will identify it as being from a certain period of time, not much else.
You really need to measure the bore and stroke to know what you have.
Royce |
| Another Horsepower Question -- Darren, 04/25/2003
Hi, I saw an earlier post showing Nascar HP ratings for FE. My '69 Galaxie was rated at 265HP stock. I just finished adding FPA headers, new 2.5in aluminzied exhaust, Edelbrock Performer RPM and Holley 750CFM 80508S Carb. Any guesses out there on what kind of increase in HP I will have accomplished? Thanks! |
| | RE: Another Horsepower Question -- Gerry Proctor, 04/25/2003
Short answer -no. Longer answer -not a lot...maybe 20 or 30 or so if you tuned for the mods. But the only way to tell is by scientific methods like a chassis dyno where you use a baseline measurement, make your mods, and do another run. Obviously you didn't do that so you have to deal with it on an objective basis. You could take it to the drag strip and gather scientific data but you still don't know where you started, only where you finished so you have no basis for identifying any proovable gain.
In the bigger picture, it really only depends on how it FEELS to you now. Do you have more torque where you want it and can you feel it in the seat of your pants?
The truth is that most of the mods that improve the breathing ability of the engine only pay off when you look at cam timing. The only time when you see big gains in intake, exhaust, and even cylinder heads is when the engine was being choaked by those things and limiting the potential of the camshaft. FEs, even in their most pedestrian configurations, have pretty good flowing intakes and heads. With few exceptions, the exhaust manifolds are fairly poor and you can see some gains in going to a free-flowing exhaust as you've done. But all the modifications that most folks make are cumulative and make their full contribution when you get to the heart of the matter and that's the cam. |
| | I'd guess you would be adding about 50HP. -- Dave Shoe, 04/25/2003
The cam is rather mild, so headers won't help as much as you'd like. If there was more cam overlap, the exhaust tune would be more critical, still a free flowing header will help, and the excellent intake upgrade will also make the headers more useful. The mufflers won't really do diddly to performance until you get a wild cam.
The intake manifold was an excellent choice with stock heads (or otherwise), and it'll let you wind the engine up as far as the cam will allow. The carb will also help, though you can expect a bunch more power with a nice easy performance cam kit. The carb is big for what ya got, but it'll run great and you can grow into it as more things change under the hood.
A cam kit is not that cheap, as you MUST replace the lifters with ANY new cam, and new springs will also be in order to close the valves at higher RPM the new cam will allow. Since the stock valve retainers are cheap stamped jobbies, you'll need to replace them (they're a part of the cam kit anyway), but the valve locks and grooves in the valves are not properly positioned for performance valve retainers, so in go new valves and locks. Only the pushrods and rocker assemblies can be reused if you upgrde the cama little.
It sounds like you'll be having some fun this summer. Perhaps the next step is not a cam, but is a set of gears that'll let your engine wind a bit quicker. Some 3.25:1 will be a nice start, 3.50:1 if you don't mind it revving a little on the freeway (still fine cross-country), and 3.70:1 if you plan to add a cam and get competitive.
If you do get competitive, you'll find the engine needs to be gone through, as lotsa nagging things start to happen when you start twisting the block more than usial - things like leaks and creaks. If you plan to drive in spirited fashion, open the block up and get to know the condition of all the parts. You don't need to replace everything you see, but you need to know what the baseline condition of the engine is, so the NEXT time you opo it open, you'll recognize whether anything is changing (wearing) in unusual fashion.
Just rambling, Shoe. |
| | | RE: I'd guess you would be adding about 50HP. -- Darren, 04/28/2003
Thanks again for all the sage advice and enthusiasm, Dave! I am sure you hear this all the time but your input is EXTREMELY appreciated. |
| Valve Covers for Erson Rockers? -- Geoff McNew, 04/24/2003
Anyone else using Erson roller rocker shafts? The adjusters hit the underside of my factory 428 "Snake" Cobra Jet cast aluminum covers. Whose cover do I need? |
| | RE: Valve Covers for Erson Rockers? -- Royce Peterson, 04/25/2003
I have a set under my chrome '68 "Power By Ford" valve covers. I have also used them under Lemans style covers.
Royce |
| | | RE: Valve Covers for Erson Rockers? -- Geoff McNew, 04/25/2003
Are the "Cobra LeMans" black crinkle finish and the "Cobra LeMans" polished identical save for finish? |
| | | | Yes N/M -- Royce Peterson, 04/25/2003
/. |
| | | | | RE: Yes N/M -- Geoff McNew, 04/30/2003
Got 'em...polished, they're sweet! Man, they are tall compared to my old snake covers...power steering booster vacuum fitting clears them by almost as much as my stage8 header bolts clear the shock towers.
-thanks
p.s. engine went in today....both super comp headers were mounted to motor (no tranny) ....just me and the wifee's extra set of eyes....no problem.....BUT! I have a slick TD engine tilter, the best damn $64.95 I ever spent! |
| Overdrive Transmission for "FE" -- Matt, 04/24/2003
Hi! I want to know if there is a direct bolt up Overdrive transmission that will bolt up to my 1963 390FE? Or if there is an adapter plate combo that someone knows about that does not cost as much as a transmission? Thanks! |
| | Borg Warner OD -- Royce Peterson, 04/24/2003
I believe 1963 was the last year for the Borg Warner overdrive in Ford products. It came behind a three speed manual transmission. Anyone know if it was offered behind a 390? I have seen it in a '62 with 292 power.
Royce |
| | | the borg warner was used at least through 67.... -- hawkrod, 04/24/2003
many F100's still had it. i like to use the orion style OD from a late 70's van or pickup. they will bolt up to an FE nicely. the caveat is they do not have any strength in the OD gear so they are for stock engines only otherwise you will end up with broken gears. i had one in one of my 62 tbirds for a while and it worked great. hawkrod |
| | RE: Overdrive Transmission for "FE" -- John M. Sutton, 04/24/2003
There were several variations of the so-called "Borg-Warner" transmisison. In many cases, the factory (Chevy, Hudson, Nash etc) would have BW manufacture their OD housing to mate to their transmission, but it would be referred to as BW's. Ford did this to some extent in their cars in the late '50s and early 60's. Hawkrod is far more knowledgeable on the cars than I am. The BW's own T-85N is a very durable and sturdy OD transmisison used in F-100s, but it is a very heavy thing, weighing out at over 175 pounds empty. I have never seen this one in a Ford car, though. I have attached a pic of it; you can see the belly of the thing that makes it big and heavy.
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| | | Overdrive Transmission types -- John M. Sutton, 04/24/2003
I neglected to mention that the car OD version can be usually distinguished from the heavier duty truck OD version by three characteristics. First, the truck version always has T-85N cast into the right side of the transmission casing itself. Second, the car version has a slip joint in the tailshaft, much like an automatic transmission, whereas the truck variant has a carrier bearing for a 2 piece drive shaft , which has the slip joint in between the 2 driveshaft pieces. Finally, the light duty version has a casting number on the OD casting with an R number. Anything R-10 or below is for a car, whereas R-11 is for the heavy duty version usually found in the F-series. |
| | | John - what's that stenciled lettering? Is that '5W30'? [n/m] -- Mr F, 04/24/2003
n/m |
| | | Oh - and how old is the transmission in your photo? [n/m] -- Mr F, 04/24/2003
n/m |
| | | | This tranny is... -- John M. Sutton, 04/25/2003
...out of my '66 F-100. It is original to my truck. I can't remember if that last digit is a 0 or a capital C, but since it is in my truck, I can't check it out! I took the picture awhile back when I had it out. Would you like more pcitures of the front and other side? |
| | | | | Sure - any photos showing markings, etc. :-) [n/m] -- Mr F, 04/25/2003
n/m |
| | | | | Cool - thanks, sir. :-) [n/m] -- Mr F, 04/25/2003
n/m |
| | | | Here is another photo.. -- John M. Sutton, 04/25/2003
.. showing the opther side, with the solenoid and shift levers
[Image deleted by Admin.] |
| | | | The R-10 casing looks like this... -- John M. Sutton, 04/25/2003
..notice how much smaller it is, because it uses a smaller, weaker ring gear as well as a smaller sun-planetary arrangement.
[Image deleted by Admin.] |
| | RE: Overdrive Transmission for "FE" -- Jared, 04/24/2003
Lentech makes an overdrive for the FE. It’s supposed to be an awesome transmission. It’s expensive. I have read about them in a few magazines. Check them out at http://www.lentechautomatics.com/home.htm |
| 390ci -- Robb, 04/21/2003
Me and another "motor-head" buddy of mine was wondering if someone can tell us what's the 390 cubic inch size after a .030 or .060 bore job.
Thanks Robbjo |
| | About 5.5 cubic inches per .030" over. -- Wayne K., 04/22/2003
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| | RE: And it's not rocket science -- Gerry Proctor, 04/22/2003
The formula for figuring total displacement is BORE times BORE times STROKE times .7854 times number of cylinders: 4.080 (.030 over 390's stock 4.050" bore) x 4.080 = 16.646 x 3.78 (390's stock stroke) = 62.923 x .7854 = 49.420 (this is the displacement of one cylinder) x 8 (the number of cylinders) = 395.360 (the total displaced volume of a .030 over 390 Ford).
If you don't feel like doing the math there are plenty of displacement calculators online that only require you to plug in the variables (bore size, stroke, and number of cylinders). |
| 390 -- Robin Scribailo, 04/21/2003
Hi,
I am (after 25 years) about to start restoring a 68 GT convertible mustang. It was originally a 390 but is now a 302. I would like to put the original engine back in. I could do the rebuild myself or have it done. Any suggestions on where to purchase, what to avoid and so on. How much would a basic engine rebuild cost? I've looked on ebay and there seems to be a decent supply of parts and motors online. I would like to keep the date codes authentic if possible. Any suggestions would be most appreciated.
Robin |
| | I'd screw the date codes. -- Dave Shoe, 04/25/2003
The first goal is to get a 390 stuffed between the wells. You can pick up a "correct" engine AFTER you're having fun. It's cheaper that way.
Pick up a nice 390 out of a 390 pickup truck from the 1970s. They are simply the most common nowadays, thoug any 1964-later 390 will do. You can identify a 390 in a 1973-later pickup because it's got the 4-barrel. 1972 and before requires a peek at the crank flange, to be sure it doesn't have the football slice cut into it in order to drill out the short 360 throw. If you can crank it over with a socket wrench, they go for $150.00 at the good outstate yards, don't even bother looking in the city, and ebay 390s are typically advertised as 427s, so you rarely find them when serching for a 390. The block, crank, rods, heads, damper, timing cover, valve covers, water pump, and a buncha other stuff from the prize pickup are gonna be the same as found in a 1968 Mustang, though the text markings may differ a bit (let's just pretend the truck markings are BETTER than the stock Mustang markings).
Beware, salvageyard blocks might be cracked in many locations because rainwater or weak antifreeze froze in them over the winter. Always be aware of this.
This engine will leave you without an exhaust or an intake, carb, or cam, but this is good, since the aftermarket is really whare you want to be with these parts. Did I already mention you do NOT really want a numbers correct engine? What you need to be looking for is a "period correct" engine, except you want it done right because they always screwed up 390 builds back in the late '60s. Honest they did.. "Period correct", this is where life begins. The next time a car show judge mentions your ride ain't concours correct, just be sure let him know it's got more personality than his entire family.
O.K., having gotten past this "numbers correct" stigma, an Edelbrock Performer RPM intake (be sure it says RPM, not the wimpy plain one) will buy you power, streetability, quality, and reduced weight, all at a top dollar discount. This will be perfect for your D2TE-AA heads, no port matching necessary. If I was you, I'd end up painting the intake blue with the rest of the engine, as this makes the engine look more stock. I always paint my intakes, as I don't like bragging. I much prefer insults.
A fresh cam naturally requires fresh lifters, as well as the matching valvetrain goodies. Nothing fancy, but if you wanna torque the nuts off the wheels, a mild hydraulic roller grind will do the trick. Since this is way beyond most budgets, there are lots of hydraulic cam kits that will take you where you want to go.
The exhaust is simple: Avoid the stock 390 Fairlane/Mustang manifolds with a passion. they're the worst exhaust manifolds ever cast for the FE, log manifolds included. This is where you need to ask your wife's permission to do a little bit of hotrodding, becauise instead of buying a set of repopped CJ exhaust manifolds, you really need to buy some FPA (fordpowertrain.com) headers for your car. Not cheap, not expensive, but they'll put a smile on your face, especially since they are the easiest header ever made to install on a Mustang (not that this is easy), and ground clearance is only topped by the workmanship of the header (I've never yet owned an FPA (because I'm poor), but I've heard bunches about them).
You'll do well with a smart looking 780 CFM Holley, or a lower maintenance Edelbrock carb of similar specs, but be sure to use a stock 1968 Ford air cleaner assembly, as these suckers breath better than any aftermarket air cleaner that you can find. In late 1967 Ford really stuffed some technology to the air cleaner, and the stock looks are a really nice touch, though the genuine "GT" air cleaner has a snazzier, meaner look. Still, there's no sin with sticking to a 302 aircleaner (like I do) and running a 1971 429 CJ air filter in it, so the lid sticks up a half inch over stock, megaphoning the intake valve howl to everyone within running distance.
The 302 frame mounts can be adapted to FE specs be adding one hole, but you still gotta buy motor insulators (common) and engine plates (readily available - don't be afraid to get the wimpy import plates, as the modern insulators will fail before anything else). I've still got to do this conversion to my '69 Mach, and I think I may need a different tranny crossmember, but am not sure right now, as I've never much worked on Mustangs before.
Obviously, you need to be careful when listening to my opinions. Still, you need to be even more careful when talking to folk who insist you try to match numbers. Those folk can put snails to sleep.
Good luck with your conversion. I sure hope you can find someone to offer good advise on the project, as I won't be held liable for any of the miscalculations I've advised in this post.
Shoe.
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| | I'm aware of no club that checks dates for 'concours'. [n/m] -- Mr F, 04/25/2003
n/m |
| | | Yeah, I was just kidding a bit about that. -- Dave Shoe, 04/25/2003
I can relate to the numbers-matching interest, but can more so recall how much time and money (mainly time) it takes to find the "correct" parts, when so much FE stuff is exactly the same.
I suspect performance is not the main goal here, but big block presence and originality is, as an original convertible Mustang does have a neat presence, not to mention higher resale value. Still, should you decide to go with Edelbrock, CJ, 427, C6AE-R, or or 1958-65 FE heads, then the FPA headers for a 390 Mustang will be incorrect, you'll need the ones for a 428CJ, due to the alternate position of the exhaust port on these heads. Also, it'll be desirable to drill and tap the undrilled exhaust bolt bosses if you use a truck engine as the basis of the build, sinc the diagonal bolts are best suited to tight fitting Mustang/Fairlane engine bays. Just had to mention that, as the port mismatch causes exhaust leaks as well as non-optimal performance.
Note that C6AE-J, C6AE-L, C6AE-U, C6AE-Y, C7AE-A, C8AE-H, and D2TE-AA all have low positioned exhaust ports which sit 5/16" lower than the other FE ports, and these comprise the bulk of 1966-70 heads, and all of the 1971-later FE heads on cars and trucks. Diectly associated with the low-exit exhaust is the small-runner "velocity" intake port which first showed up in 1966 to help the FE meet new emissions laws. The stock head performs great up to about 400 horsepower, beyond that level of tune, you gotta start porting it. It's the best performance head for milder 352/360/390 builds, as it has great streetability in combination with efficiently flowbenched port design, but it lacks the raw air passing power of the earlier head, something that starts to become apparent at about 400 horsepower.
C8AE-H heads woud be correct for your car (C7AE-A are O.K. early in the 1968 model year, JMO), and if it was a "GT" cammed engine, it would need thermactor ports drilled in the head, and a thermactor system on the car to meet tougher 1968 emissions laws. At the start of the 1969 model year the 390GT engine disappeared, as did expensive thermactor on the 390, resulting in the decammed 390IP as the top dog 390.
Sweat the thermactor conversion some other time. Just get the car running nice now.
JMO, Shoe. |
| | | | RE: Yeah, I was just kidding a bit about that. -- Robin, 04/28/2003
Shoe,
I appreciate your help. After all these years I would like to get it on the road sooner than later.
Robin |
| | | | | Well, if you need more info just ask. :-) [n/m] -- Mr F, 04/28/2003
n/m |
| FE intakes -- Randy, 04/20/2003
I'm using an edelbrock rpm and feel it is a restrictor in my 428 air pump. Does anyone have coparisons to Offenhauser's port-o-sonic? I'm looking at street-strip pieces, not full race. Dove makes claim of incredible power gains using their med. riser single plane over edelbrocks rpm and out torqueing the rpm over 2500. If other folk's could verify this, I would jump on it, but it's a 600.00 piece so it better be worth it . What do you all know about the dove piece and offenhauser? |
| | RE: FE intakes -- Travis Miller, 04/20/2003
If you are talking about the Edelbrock Performer RPM intake, your "restriction" is probably somewhere else. That is a great street-strip intake. Give us some other specs on your engine and type car such as carb, headers, trans, rear gears, etc. It takes an entire combo to make usable power. Also what are you looking for in performance? |
| | | RE: FE intakes -- Randy, 04/20/2003
There's definately something wrong in my motor package. Here's some specs and some dyno #'s. 428 block-.030 over, stock rods, forged pistons w/ 9.85:1, Edelbrock rpm heads w/ 2.19 in.-1.72ex. flowing 300cfm and 240cfm @ .700. Schnyder cam w/ .230 @ .50 both sides and .525 lift, hyd. flat tappet. Perf. rpm intake, holley 800 dbl. pump. FPA tri Y headers, 2 1/2 pipe into flowmasters. C-6 fully built, 2500 stall. 9" w/3.25 track loc. After running a best of 13.1 at 104, I took it to a dyno shop for a tune session and left with no answers. These are sad numbers and no one at the dyno shop or my motor shop can say why. Also these are the best #'s of the dyno session and it's with open headers. H.p. is 262 at 4891 rpm, tq. is 472 at 3127 rpm. Something is really wrong with that. The car was hooked up to a scope first, seems to be right. Timing is 36 and all in at 2500. We changed carbs to a holley 950hp and showed a gain of 4 hp. Anyones best guess is it just does'nt seem to be breathing good enough, as for me , I'm stumped on the 262 hp at 4900 rpm. It would be a good motor for hauling a trailer load of cattle. MSD 6al and duraspark dist. Any ideas? |
| | | | RE: FE intakes -- Bob Sprowl, 04/20/2003
You wnated ideas: Cam seems a bit small and how did you figure the Compression ratio.
Edelbrocks are not always what they claim out of the box regarding ccs. |
| | | | Cam, compression ratio -- Royce Peterson, 04/20/2003
You need more cam to use the airflow available in your intake and heads. Yet your compression is too low to take much more cam. The low compression ratio is well suited to a mild cam like the one you have selected.
To get more power another point in compresion ratio and a cam with specs in the 240 duration at .050 / 600 lift would make another 100 HP at the rear wheels.
Also your timing is way too conservative with low compression and mild cam. You might pick up 25 horsepower just by allowing advance to reach 40 degrees. It should not ping with the low cylinder pressure you have and aluminum heads. |
| | | | | RE: Cam, compression ratio -- Randy, 04/20/2003
Thanks for the input guys, I'm not a motor builder, as you can tell. Compression was figured with a 10 to 1 flat top and 72 cc chambers cleaned out to 74cc. I would gladly make the changes in comp. , cam and timing for another 100 hp. Can I get to 11 or11 1/2 without new pistons? How much cam can I use and still drive from Az. to Cal., N.M. It still doesn't seem like my present cam would peak at 4900. What would hold it down that low? |
| | | | | | Cam specs -- Royce Peterson, 04/21/2003
That cam would be considered daily driver material if it was in a 350 Chevy. You did not post the lobe displacement angle but generally the LDA can have some effect on power also. The engine being 428 cubic inches and the cam being very mild keeps the power band low.
For an FE a cam in that duration (230 at .050) generaly has at least .550" lift. Schneider is a very old cam company, the grind you describe sounds like something from the 1960's.
I don't know a good way to increase compression that much without changing pistons. Milling heads and intakes can have disastrous results if not done properly. Also the valve clearance will likely be a problem when you increase cam specs so the pistons might end up coming out anyway. |
| | | | | | RE:Valve Spring installation? -- McQ, 04/21/2003
Just a quick recommendation based on your statement about "peak at 4900 RPM". Be sure to check your valve spring installation height. If they are not installed/shimmed correctly you will have problems with upper range RPM, i.e., above 4,500. Your cam is mild but based on the specs provided it should make reasonable power to 5,500. |
| | | | | | | RE:Valve Spring installation? -- Randy, 04/23/2003
If those are 350 chevy cam #'s, that sounds about right cause thats all the power I'm getting. Springs are new ( as is everything else) and came with the cam, they have 130lbs seat pressure and 310 open with plenty of room for the lift. If that is all I'll get out of that package, then that motor is coming out and changes will be made. I'm looking for the right package to get to the 500 flywheel hp mark. No, I'm not made out of money. Those power #'s are b.s. for a 428 and if they were acceptable, I'd just throw in a 302. So, compression is too low and cam too small.Any advice for a 400+ rwhp driver would be appreciated. Going to Cal. this weekend for an all ford show so I can't start tomorrow. |
| | | | | | | | I always get into trouble for this one.. -- james, 04/23/2003
Put a 460 in it. Let the hate mail begin. (just teasing) |
| | | | | | | | | RE: I always get into trouble for this one.. -- Randy, 04/23/2003
I thought of that before I started this project, parts are much more available, more cubes, etc. I elected to go 428 cause this is a 67 390 mustang and everything would match up and be period correct plus big power, or so I thought. I'm sure it's possible but this is the second build on this motor from reputable ford shops and I've yet to get 300rwhp. What bull. You'd think this was rocket science. |
| | | | | | | | | | Should get over 400 hp, even with low CR -- John, 04/23/2003
Unless your lifters are getting the pressure they need (you arn't using those variable bleed off ones are you?)I'd say the cam is way out. The cam needs to be matched to your CR. Why don't you spend about $30 for desk-top dyno and run your info through it. I havn't tried it, but it's a well thought of piece of software, and I intend to purchase it some day. I called Crane when I did my engine and they put my numbers through their program. They predicted 480 Hp with a 9.5 CR and a fairly mild solid lifter cam. I think that is optomistic as it calls for "perfect" tuning which I doubt I have, but by the way the car runs, I know it's well up there. By the way, this dyno testing you had done.....was that a wheel dyno with the engine in the car, or a engine dyno. You'd be surprised how much you lose, especially with an automatic tranny. As for getting a CR above 10, well.....you will get away with it with Al heads, but not with "FE" heads (a pun here). Today's "high test" just isn't what was available in the 60's when these motors were available with such high CRs. And now comes the critiques of my posting............... |
| | RE: FE intakes -- Geoff McNew, 04/24/2003
Could the bigger valves in your 76cc Edelbrocks for 427's be shrouded by the smaller 428 bore? Their 72cc head for 390-428's uses 2.09" & 1.66" 428CJ valves.
Also, is your timing mark and dampener actually at true TDC using a piston stop? The timing pointer on my SCJ was 6 degrees retarded; i.e., I was getting 32 degrees when I thought I was getting 38....only ran 104 mph in that state as well.
(I assume you degreed the cam off true TDC?) |
| | | 428 times at the track. -- James, 04/24/2003
Most of the 428's that I have been around ran a 14 flat from the factory even with some good meats under the fenders (I didn't say slicks). To get a 13.1 out of one with a cam and decent heads sounds pretty good for an old FE if you ask me. |
| | RE:36 deg.s timing -- S.Vincent, 04/26/2003
Randy, most FE`s wont have enough power to get out of their own way at 36 deg.s. Try using a premium grade fuel and setting your timing to 40 and all in by 2000rpm`s. I think you will be really suprised! Oh yeah...and I think your cam is too small also. Try a more modern camshaft such as one from Lunati or comp. and look at a lift closer to the .600 mark. Keep us informed! |
| | | RE:Oh yeah, 1 more thing -- S.Vincent, 04/26/2003
Your gearing is way too tall. I would definetly drop the gearing down to about a 3.89 or a 4.11! |
| 428 Compression Ratio -- Mark, 04/20/2003
FE-Heads,
How high a CR are you guys running on today's Super Unleaded? What is the highest you petroleum engineer gear heads recommend? |
| | RE: 428 Compression Ratio -- Wes Adams, 04/29/2003
I have a 428 CJ that is running 11to1 out on the street everyday for a daily driver!! |
| speedometer gear? -- Greg, 04/18/2003
I have a '69mach I 428 cj w/c6. The p.o. replaced the original 3.50 rear gears with a 3.91 trac loc. I'll be replacing the speedometer cable this weekend and need to know how close I can get to accurate at the speedometer without the use of a reducer or changing the rear. How many teeth ? Greg |
| | | Please check my math....;) -- Greg, 04/19/2003
Never got algebra or math in general at all.(history major). So please check my figures for accuracy. Given that an 18t with 3.50 was correct, then a 20.1 with a 3.91 should be very close, (rounded down to 20 of sourse). Did I get it right? Greg |
| | | | Yep - that's right. You get an 'A'. ;-) [n/m] -- Mr F, 04/20/2003
n/m |
| | | | | New wrinkle/issue... -- Greg, 04/20/2003
Got the old gear out this morning and it's a 21t, using the formula the new gear needs to be a 23.46 (23) does such a thing exist? If not can the drive gear be changed to achieve the same result? |
| | | | | | | RE: 23? I think you're SOL. Meanwhile... -- Bill, 04/22/2003
I have a 68 1/2 cj, 3.91 car with a C-6 that does have a speed reducer. I have now installed my 4.30 N locker set-up. Will this just require a speedo gear change or a different speed reducer. thanks |
| | | | | | | | Keep the reducer and calculate the new gear req'd. [n/m] -- Mr F, 04/25/2003
n/m |
| | | | | | | | With stock-size rims/tires, 4.30 driven gear is 18T-Grey. [n/m] -- Mr F, 04/25/2003
n/m |
| | RE: speedometer gear? -- DennyR, 04/24/2003
I believe on one of the forums someone said that jeep had 23 tooth gears that would work. I don't have 1st hand experience with this but it might be worth checking out. Also www.baumannengineering.com sells these. |
| | | Eureka!! -- Greg, 04/25/2003
Found a source for 23t gears at a local mustang restoration place. If Mr.F is o.k. with it I'll post the name. Greg |
| | | | Sure, no problem - but let's see if it works first, Ok? :-) [n/m] -- Mr F, 04/25/2003
n/m |
| | | | | O.K. n.m. -- Greg, 04/26/2003
n.m. |
| Gearing -- Gary Goblirsch, 04/18/2003
I would like to know what type gearing works best for 390 with top loader transmission?I dont know what gears are in tranny but rear end is 2.75 . How do get info off trans. and where is located?What rear gears do you sugest?The cam is lift 287-297 valve505-526 clutch 3400 lbs.Thanks |
| | RE: Gearing -- McQ, 04/18/2003
A 390 with a toploader? Your specific requests for information are difficult to provide answers to without a little more information. But here's an attempt to hopefully help you a little.
First, tranny info can be found on a metal tag attached to the side of the toploader(4 speed I'm assuming but there are 3 speed toploaders that were attached to FEs) but it's about 1/2" by 1" and it'll say RUG-.... this is the info you need to find out what the trans you have was originally bolted to.
It's very likely that you have a rather common big block toploader 4 speed that featured a 2.32 low gear with close ratio gears. Which in combination with your 2.75 rear gearing should provide for quite a slug pulling away from any line, stop or drag strip.
Personally I have found 3.89:1 to be excellent all around rear gearing with a 2.32/close ratio trans and mildly built FE. The 3.50:1 isn't bad either again for all around driving. |
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