Build up 302 or drop a 460

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Thanks guys for all the input. I finished rebuilding the carb, drove it around, and I definitely want some more power. I also own a 98 LS1 Trans Am (which I am trying to sell) and can definitely feel the difference (obviously the 98 is a lighter, more powerful car). The exhaust leak sounds bad. For now, I think I am going to focus more on the transmission and rear end before deciding what to do with the motor.

I found an ad for a 1980 F150 which supposedly has a 1972 351C 4v CJ motor, C6 tranny, and 9" "posi" rear end for $950. Sounds like a good starting point considering most of the built 351w I have found locally start at $2500. I know the Cleveland engine does not have nearly as much aftermarket parts as the Windsor, but still looks like an option to consider.

Is there a kit out there to swap an 8.8" rear into a 71-73 Mustang? It seems like a good option to get rear disc brakes.

What gear ratio is numerically too high for some highway driving and an original C4/C6? Anything over 4.0? If I am going to focus on transmission and rear end, maybe I should go with a T5 and lower gears? There are so many options to consider...
I have an 8.8 out of a Sport trac Explorer. Pretty easy swap if you can weld. And most of them came from the factory with 31 spline axles, 3.73 gears, posi and disc brakes all in one shot.

I am running a c4 trans in mine with 3000 stall converter.

 
It seems that keeping a small block is the less complicated way to go. I want a street car that has a good amount of torque and good throttle response. I am not looking for big hp at high RPMs. Based on what I have read, the 351C 4v is designed as more of a higher RPM engine as opposed to stock windsor (302/351 engines); which is not what I am looking for. Would something like changing the cam give me more torque at lower RPMs without any other major mods required?

I am having difficulties finding a 351w block. I have found a 71 short block which will need rebuilding for about $200. I have also found a 302 mexican block bored 60 over with 289 HiPo heads, a 268-270 comp cam and Edelbrock performer intake with an asking price of $1k and they will throw in a 750 Holley for an additional $150. There is also a 302 long block from a 98 explorer with GT40P heads with 12k miles for $800 (no intake or exhaust manifolds); and comes with an e303 cam. I know the GT40P heads have the drawback of having the spark plugs at an odd angle which reduces the headers that can be used with that motor. The advantage is that it is a roller block.

I dont know if I will be able to get enough torque out of a 302 though. I do not want to get into stroking as from what I have read, a well built stroker (including heads, manifolds, etc) can come out to $3k-$5k, and I dont have that kind of money to spend on a project like this for now. I have read some articles where with a couple of bolt-ons, porting the heads, and putting the adequate cam the 5.0 motors can get close to 300 hp/ 320 lb ft of tq.

Back in Central America, I did not have these many options. I was pretty much stuck with what was in the car. All the possibilities available here are kind of driving me nuts making it difficult to decide what option to choose.

 
So I eventually bought a 73 351w for $300 which needs rebuilding. I have found an 84 351w already rebuilt with about 20k miles going for $900. I assume I will end up spending another $1300+ dollars to get the engine rebuilt. It has made me wonder how much more power will I get from a stock 351w 4 bbl when compared to my 302 and throwing in an edelbrock performer intake along with an edelbrock carb?

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The horsepower will be similar but the windsor will have noticeably more torque. I love my 351 windsor in my fastback, to me it is easier to work on and fits great in the engine bay.

 
My '68 coupe came with a 302. When i finally had the $, I pulled the 8" rear, the c4 auto and the 302. I dropped in a Currie 9" rear, a TKO-600 and a 393w. Night and day (obviously), but it makes great power, I don't have to wind the snot out of it to make any power and it stops and handles well. Don't forget you can go with a 408w and a 427w as well. Not to mention the stroker optioned available for the Cleveland. Not saying a stroked small block is better than a 460 at all. You could even go with a stroked big block (521/545). Just another option..

 
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I sold the 351w and made $50. I bought a complete 460 which seemed to be in working condition. Then I found a guy selling a 460 and C6 combo out of his hotrod for $1k. I sold the 460 and made $250 on it thinking I'd buy the combo.

This 460 has a Weiand intake and a 650 cfm 1406 carb; an HEI distributor, and everything else is stock. I don't think the motor will fit with that intake though. I figure I'll need to buy the $300 mounts from Crites, a C6 crossmember ($60), front coils ($80) and shorten the driveshaft ($200) to get that motor in my Grande.

I'm thinking what if I spend those 1000 bucks on my good running 302? I have found some Windsor Sr heads for $500, already have an Edelbrock intake and carb, can probably get headers as well. I am just not sure if the 302 with those mods will make comparable power with the 460.

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Tataocb,

As much money and time to get the machine work, plus getting all the parts, I would do a turn key setup over having my 1984 GT 302 roller rebuilt.

I know this is way off budget base.

https://prestigemoto.com/347-ford-stroker-crate-engine-425.html

111jn12.jpg


Dyno Tested / 3 Year Warranty

Horsepower: 425

Torque: 425

Bore / Stroke: 4.030 x 3.400

Compression: 10:1

Fuel Requirement: 91-93 Octane USA 95+ RON

This may give you an idea to look at possible way.

mustang7173 :bravo:

 
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A 302 will never be able to make what a 460 does on the low end, which is torque. Torque is what gives you the seat-of-the-pants feel on take-off. The more you build a 302 the higher up the RPM range the power range will be. Generally, the longer the stroke is compared to the bore the more torque an engine will make. The 302 (as well as most Ford auto engines) is an "over-square" engine with a bore bigger than the stroke (4.00" bore by 3.00" stroke). The 351W, C, and M are 4.00" x 3.50" and the 400M is 4.00" x 4.00". The 429 is 4.36" x 3.59" and the 460 is 4.36" x 3.85". The 427 Windsor stroker is 4.125" x 4.00".

 
Tataocb, you are my hero. You keep buying engines, changing your mind and making money in the process. I say just keep doing that until you find what you want. If nothing else you will have some extra cash. Sorry I don't have any good advice besides that.

Scott

 
Tataocb, you are my hero. You keep buying engines, changing your mind and making money in the process. I say just keep doing that until you find what you want. If nothing else you will have some extra cash. Sorry I don't have any good advice besides that.

Scott
Lol.....yeah, luckily I have been able to make money on these.

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Just my 2-cents from my my personal experience. I've done it both ways. Bought a '71 351 windsor out of a cougar for $150. bought a Scat stroker crank to take it to 393. Comp cams 270 or 280, can't remember exactly, stock heads re-worked, low-rise dual plane intake, and holley 650, MSD electronic dist. Builder charged me $1650 to build it, Including the crank. Problem was he used the wrong pistons, I put it in the car and it was wicked but had problems with detonation. CP turned out to be 14:1. He rebuilt it and I added AFR170 heads. Little motor dynoed at 425HP and 450 torque but went flat above 5500 rpm. Limiting factor was intake design. BUT, Thats what I wanted it for-low end torque. Great relatively inexpensive street motor. While that motor was on dyno I came across a 427FE side-oiler. this was going in a 68 shelby GT500 so I decided it needed the big block. Paid $4000 for a non-running 427. Had a bad cam. Followed pretty much the same formula -comp cams, MSD, except had ford Medium riser 2-4 intake with 2 600 cfm carbs, added eldelbrock alum heads. In taking the engine apart to freshen up and replace cam, found out that it had been stroked "Old School" by offset grinding a forged 391 truck crank. Swapped the 393 in the car for 427. Driveability and handling were night and day. 393 was light and responsive, 427 was nose heavy. Of coursed 427 was much faster on top end, it never stopped pulling, but in retrospect, for a daily driver, the stroked windsor was a better choice, and much,much,much less temperamental and expensive.

 
Mbrew2 - thanks for sharing your experience. I think a "windsor" is probably the less complicated way to go.

Continuing with the tradition of buying parts...I got this great deal on a pair of complete 289 C6OE 54cc chamber heads with relapped valves and new valve stem seals, 2 bbl intake and autolite 2100. I thought I might use the heads to raise compression, but I am not sure since these probably won't flow much better than the current heads. But the deal was too good to pass.

I checked the tag on the rear end and the ratio is 3.00. The motor has a hesitation when I hit the gas from a complete stop. I rebuilt the carb a couple months ago. The accelerator pump is working as I can see gas going in when I push the accelerator pump rod/linkage. I cleaned up the balancer. The distributor was hooked up to manifold vaccum and the initial timing was set to 6 BTDC, so I hooked it up to ported vaccum and set initial timing at 10 BTDC. I hoped that would fix the issue, but it did not. When I hit the gas it's sometimes it will just shut off. I thought I'd try the autolite carb I got as part of the deal, but the linkage is setup for a manual transmission.

Any idea on what else to check or should I start a new thread? If I try to swap the linkage between the 2 carbs, do I need to disassemble the throttle shaft and throttle valves? My current carb is a 1.08, the one I got as part of the bundle is a 1.14 venturi.

I know a 2 bbl and 3.00 gears won't feel too powerful off the line. Would a performer intake with a 1406 make a significant difference? Or will most bolt ons not really make much of a difference with 3.00 gears?

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So I eventually bought a 73 351w for $300 which needs rebuilding. I have found an 84 351w already rebuilt with about 20k miles going for $900. I assume I will end up spending another $1300+ dollars to get the engine rebuilt. It has made me wonder how much more power will I get from a stock 351w 4 bbl when compared to my 302 and throwing in an edelbrock performer intake along with an edelbrock carb?

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you will spend a lot more than 1300 rebuilding it.

you will get a lot more torque/power

 
if your 2v carb has 49 jets or smaller and you live near sea level, i would drill them out with a number 55 drill.

i would also do a compression test.

those heads you bought are worth around $50.00 - $100.00 where i live.

 
I know a 2 bbl and 3.00 gears won't feel too powerful off the line. Would a performer intake with a 1406 make a significant difference? Or will most bolt ons not really make much of a difference with 3.00 gears?

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With everything properly tuned and running as optimally as possible, there would be a noticeable increase in power between the 1406/Performer and the 2bbl/2V intake - not a huge increase, but definitely noticeable. The 3.00 gears are indeed a limiting factor, since they're designed more for cruising, economy, etc.

I have a 1406/Performer intake on my 351C-2V with the stock heads (mildly worked over by my machine shop, though), and it runs great. Lots of power - arguably more than what would've come from the factory, but then again I already have all the go-fast goodies built into it (since it was seized when I got it). I also have 3.00 rear gears, but I can't say I'm completely disappointed in those, either. I do think the AOD is locking up the torque converter into OD too early at such low rpms, which could be remedied with 3.50 gears (and would make the low-end more fun). But the '89 5.0 vert my AOD came out of had 2.75 rear gears, after all. So, I'm kind of on the fence about what to do about that (a quick blip of the throttle unlocks and drops it back to 'D' with no issues, but that's not going to cut it as a long-term Band-Aid).

In your case, I'd have to say that you can't fix fundamental issues by simply bolting on a bigger funnel for more gas to be dumped in. You need to determine if your issues are fuel starvation issues, flooding, or something else altogether. If they're fuel starvation issues, then sure - the new carb & intake should have an impact on that. If it's flooding, then the new carb & intake would only make it worse.

I'm thinking it's something fundamental (timing-, compression-, or induction-related). You mentioned needing to go with a solid-state ignition system - I'd go with that first. Start with basics.

  • Get a compression test done
  • upgrade to solid state ignition (Pertronix, MSD, Duraspark, take your pick)
  • ensure you have no vacuum leaks and/or fouled plugs
  • check the cap, rotor, spark plug & coil wires
  • get the timing stabilized and set properly
  • get your throttle linkage issues sorted out
  • Exhaust leaks taken care of


If the engine's running well, then consider a set of 3.50s for the rear end. Any numbers much bigger, and you'll start losing top end and any hope of fuel economy is out the window.

Once you get those things sorted out, then worry about carb, intake, heads, cam, rockers, headers, etc.

I'm just thinking along the lines of simply things to start with, because it's a lot easier to find ways to make more power if you're not troubleshooting while doing so.

 
I like my 3.50 gears. My car can easily light them up if needed. You can wake up a windsor pretty easily with the right parts on it. The 600 carb should work fine when properly tuned.

 
In your case, I'd have to say that you can't fix fundamental issues by simply bolting on a bigger funnel for more gas to be dumped in. You need to determine if your issues are fuel starvation issues, flooding, or something else altogether. If they're fuel starvation issues, then sure - the new carb & intake should have an impact on that. If it's flooding, then the new carb & intake would only make it worse.
Great advice! I decided to start with that. I took off the carb and noticed fuel doesn't come out when I activate the accelerator pump. I bolted on the Autolite carb and it seemed to Rev fine (but the linkage is for a manual trans). I took it off and noticed that fuel does come out when I activate the accelerator pump.

So I inspected the accelerator pump assembly on the Motorcraft and the spring was on backwards, I changed that and now it leaks fuel out of one side of the housing. The diaphragm looks fine, but I guess the housing might be a little warped or the passage is blocked. I will switch out the housings and try again, or might end up swapping the shafts along with the linkage from one carb to the other. If I do that, I wonder if I can swap the choke assembly as well as the autolite is heat activated while the motorcraft is a combination of heat/electric.

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I took off the carb and noticed fuel doesn't come out when I activate the accelerator pump. So I inspected the accelerator pump assembly on the Motorcraft and the spring was on backwards, I changed that and now it leaks fuel out of one side of the housing. The diaphragm looks fine, but I guess the housing might be a little warped or the passage is blocked.
You can put a piece of 120 or 180 grit sandpaper on a granite couter top or window pane and sand the accelerator pump housing until it has a little shine all the way around . the corners will have the biggest shine because they are bent the most . the power valve covers on the old carbs are also usually warped and can be surfaced the same way.

Do not connect the choke to the ignition wire . use the 9 volt post n the back of the alternator

 
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I let it sit overnight, and the next day, once the gasket had dried up, it sealed up the leak.....the mysteries of science. Regardless, no fuel came out the bottom when I hit the gas. It would still bog down. So I guess it is a blocked passage. I ran a string of copper wire as far in as I could, but still, the same result. When I spray carb cleaner into the passage, nothing comes out the bottom. How do you fix something like that?

So I took it upon myself to swap the throttle shaft with the linkage between both carbs. It took a couple of hours to get it done, I also swapped the choke housing to get an electric choke. When I put it back on, it leaked fuel from the filter that acts as the inlet. I turned it with the wrench and it broke...leaving the threaded part stuck in place. I thought I was screwed. Then I ramed one end of a set of pliers as far in as I could and started turning it, and the piece came out. I had a spare filter so I used it, started the car, set the idle speed to 950 rpm, adjusted the mixture screws, readjusted the idle speed and took it for a test drive. It still doesn't have the power I am looking for, but at least the tire (open differential) screeches when I hit the gas coming out of a full stop.

I think I am going to wait with the exhaust leak, and just install a new full exhaust system when it comes time for that. I was thinking of using boom tube mufflers...hehe.

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This 460 has a Weiand intake and a 650 cfm 1406 carb; an HEI distributor, and everything else is stock.
This motor with a C6 transmission is now sitting in my garage. I think I have made up my mind now...hehe. It only cost $50 more than what I sold the early 80s 460 for.

It comes with motor mounts and the insulator, but they might be slightly different than the ones in the Crites kit.

Unfortunately the C6 is the long tailshaft version and came from a column shifter car. Can the long tailshaft version be used in my Mustang by modifying where the crossmember bolts to the bottom of the car, or do I have to convert it to the short tailshaft?

 
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