What would you have to do to make a 5.0 fox run 12seconds flat? Motor is a stock NA with a carb so the question is open to anyone who has done it or think they can build a motor to do it. Setup is to be run on motor only with NO power adders. Reason being its a bracket motor and run in the IHRA street class. Would you start with ported heads, compression and forsure a cam change. Next would be gears to get it to move and a lot of converter. This is for 1/4 mile raceing and would be fun to build on the cold winter day. Lets hear you thoughts if it could be done.
Fox with a NA 5.0 to run 12 flat?
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As stated IHRA street/sportsman rules have a few rules so check those out. ET cut off is 12 flat so that was what the young guy was trying to do. I think his budget is some where around $1500 and it is driven to the track and back home. This combo is to be built off of a stock roller 302. Keep in mind this is for all things to make the car run very low 12s. Gears, tires, converter, cam, porting, intake, carb ect. Their is a lot of 302 used parts out their for a good price. Just asking for some one that has done it if it can be done with that kind of a budget. Right now its a 14.50 car with all stock 302 stuff. Car already has the 8.8. I will put out my ideas later but just wanting to know what other would do first.
I dont think $1500 is gonna do it. You're gonna need a bottom end capable of high rpm runs that will stay together. Built right, the motor alone is gonna eat up that money and more.
For trans I'd say C4 automatic with about 2800-3000 stall and a 3.73 gear.
For trans I'd say C4 automatic with about 2800-3000 stall and a 3.73 gear.
Heads, cam, intake, carb, headers, shift kit, gears, 4-cyl springs for the front, cut a coil off in the rear, and tires. Oh and a fuel pump & a tune. So, if you can do each of those for about $100 a piece, then you'll barely make your budget. I know I'm being a little snide, but knocking 2.5 seconds off of a car for $1,500 is a hell of a tall order without forced induction.
- Mar 2, 2015
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Here's an old thread on this topic...
https://www.stangnet.com/mustang-forums/threads/bob-cosbys-12-second-recipe.853108/
https://www.stangnet.com/mustang-forums/threads/bob-cosbys-12-second-recipe.853108/
Anyone else kind of surprised the underdrive pulleys knocked off 2 tenths? Although it was only a 1mph difference so it may be that it was driven better
Back to the 12sec 1/4 question. If you find all the parts used it may be doable for $1500, but you’ll be piecing together things for awhile. Sometimes you get lucky and find someone selling a used intake, cam and heads for good prices though.
I’ve seen used gears go for $80-100, used roller cams for $120-$140 and I picked up my last Vic Jr for $100. You just have to be patient.
I’d like to point out that knocking the et from 14.5 to 13.5 is pretty easy. But getting it from 13.5 further down to 12 flat, that’s much more difficult task.
If it’s a bracket car, then consistency is a the more important factor in winning competition than et. Why not aim for a 13 second bracket car? Then you’ll not have to worry about running out faster than 12 flat. And, more of your budget can go to mods that can improve consistency rather than low et.
If it’s a bracket car, then consistency is a the more important factor in winning competition than et. Why not aim for a 13 second bracket car? Then you’ll not have to worry about running out faster than 12 flat. And, more of your budget can go to mods that can improve consistency rather than low et.
It can be done.
I' knew a guy way back that ran 12.50's with a fairly stock coupe. Was a hardcore track guy.
5 speed car, Gears, pulley's, exhaust, 75mm mass air (this is track tested to get you .2, I know this first hand, took my stock car back in the day from 13.8 to 13.6).
No belt, with this little electric motor and add on belt just running the water pump.
4 cyl springs, drag radials, disconnecting sway bar.
The problem is keeping the car complete.
We all know i'm no fan of stripping out a car, but you lose the seats, sound deadener, ps, ac and any other unnecessary parts it gets easier (now you just have a slow ass race car).
You also have to be a guy that is really going to frequent the track. You don't get killer results without a lot of testing.
Employing every trick in the book and being able to do all your own work will get the job done, but it really takes dedication to the task.
For example, head shops get like $600+ to port heads, if you are details guy, have the tools, time and patience, it can be done. If not you will just have 2 really heavy paper weights.
I think the real issue here is going to be getting an aod to do all of this. Converter and shift kit is going to help, but I still think it sops up too much power. Maybe a manual valve body (although I don't know anyone that has really made good use out of one of them in a street car).
I' knew a guy way back that ran 12.50's with a fairly stock coupe. Was a hardcore track guy.
5 speed car, Gears, pulley's, exhaust, 75mm mass air (this is track tested to get you .2, I know this first hand, took my stock car back in the day from 13.8 to 13.6).
No belt, with this little electric motor and add on belt just running the water pump.
4 cyl springs, drag radials, disconnecting sway bar.
The problem is keeping the car complete.
We all know i'm no fan of stripping out a car, but you lose the seats, sound deadener, ps, ac and any other unnecessary parts it gets easier (now you just have a slow ass race car).
You also have to be a guy that is really going to frequent the track. You don't get killer results without a lot of testing.
Employing every trick in the book and being able to do all your own work will get the job done, but it really takes dedication to the task.
For example, head shops get like $600+ to port heads, if you are details guy, have the tools, time and patience, it can be done. If not you will just have 2 really heavy paper weights.
I think the real issue here is going to be getting an aod to do all of this. Converter and shift kit is going to help, but I still think it sops up too much power. Maybe a manual valve body (although I don't know anyone that has really made good use out of one of them in a street car).
Yeah, admittedly it is a little surprising, but definitely believable. I dropped from a 12.98 to a 12.63 by going back to my underdrive pullies and removing the stock fan. See posts 29 & 31 here: https://www.stangnet.com/mustang-forums/threads/new-hatchback-black-jack.884727/page-2#post-8915086
I think... Are some of you guys missing that the OP is asking to go 12-flat?
Getting into the 12s for $1,500 = no problem. Getting to 12-flat = 300 rwhp + good traction. I just don't see it for $1,500, even with used parts, especially with an auto.
Getting into the 12s for $1,500 = no problem. Getting to 12-flat = 300 rwhp + good traction. I just don't see it for $1,500, even with used parts, especially with an auto.
Three tenths definitely would feel quicker based of your seat-of-the-pants speedometer as well.
I agree with running a 12.00-12.09 being very difficult - if not impossible, unless you’re crafty, with only $1500. The difference been 12.9 and 12.0 is quite a chunk of power.
Yep, you should feel 3 tenths for sure, and it legitimately picked up 3 mph. So, you know it's a power difference. I guess it's still a question whether pullies alone would do it, because the fan was probably a big part of that, and I don't know how much the weather played in on that. It was a week apart at the same track, but the temps might have been a bit different. Still, it leaves room in there for pullies to make a 2 tenths difference.
I just read the posting from Bob Cosby and picked up a few pointers. Looks like the be ET pick up were the pulleys and porting the heads. I am assuming that you already have the sub frames done, TQ box kits installed and a set of headers and ex on the car with all the usual tricks at the track. The kid has most of the usual things done and has a season behind him already, just wanting to go faster. Seeing that its a carb setup with a HEI how much timing can you put in a 302 and lock it in??? As for porting a set of stock heads, many mags have the basics on doing it with a porting kit and a air grinder from Summit or most of the mail order companies. I have done 3 sets and it isn't very hard to clean up the rough edges and open up the ex. side. (They don't call them peanut port for nothing)..Good valve springs roller cam and something else I found that anyone can do is to STROKE IT. Comp products has a balanced kit for the auto for $950. Leave it a standard bore and just assemble it. I am thinking if you have half a brain and can read a book and have time to find the new and used parts 12 flat is not that hard. Remember it is easier to slow down then to speed up. I know what a fox with a 350 truck SBC and a cam and the usual parts will run a mild tune and a 1.89 60 ft with glide. I think the most improvement comes with the ported heads bigger cam and a stroker kit not sure what a 28-3200 converter cost but it would be a big help in the 60ft. Those ported heads and the extra 45 inches would do it easly. Just my thoughts.
Yes... I mean outside of the budget you specified, 12-flat is no problem. Cheapest approach is a set of aftermaret aluminum cylinder heads: AFR165 or 185, TFS Twisted Wedge or 11R series 170s or 190s, & edelbrock performers would all fit the bill. Ported Cobra (even stock would cut it), Edelbrock performer or performer RPM, or Holley systemax intake. A 224+ cam, and all supporting mods (fuel, intake tract, gears, springs, control arms, etc...), and it's an 11 second car. No need for the stroker. Also, it's in your customer's best interest to spend money on a quality head, vs. porting on the stock head unless he was running old factory stock rules. Stroker is for when you want 350+ rwhp.
Good luck!
Good luck!
I did say it was to be $1500. The car has a few of the very basic things done already. The question is can you make enough power with a 302 motor and a auto to run 12 flat or very close. I know that if you through a bunch of money at it things will happen. Just trying to make things better using your head. Go back to basics and get your hands dirty. I like thinking more like ported heads, better used cam, looser converter, more gear and better traction.
It's already been said, but on that budget it is going to be very difficult. It could be done with a low rear gear, the right convertor ( which may take a few tries to get right), some iron gt40's, and an ots cam. The heads will need port work, good springs and a valve job, they will also need to be milled because you will need all the compression you can get. You will need the appropriate exhaust and fuel too. Maybe if you are very frugal you can do it at that price, but i would be very doubtful. Also, you need to make the car as light as you can, like 300 or 400 lbs lighter.
Keep us updated.
Joe
Keep us updated.
Joe
- Mar 2, 2015
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I can remember back in th he 90s we all wanted to get into the low 12s. It took guys a bunch of money to break into a consistent low 12 second car. You got to figure it like this....
You'd have to have more power than it takes to run a 12 flat to be consistent. If you have a day where you have traction issues...or launch issues you need to have a little power on tap to get back to that low 12. If the bracket class stops at a 12.00 you'd be crazy to want that to be your aim. Dialing in at 12.50 would be the safest way ( I would think ). That way you have some time to overshoot without being kicked out that class.
Now, if the young guy wants to get the car to 12.5s....that's a bunch cheaper than low 12s consistently.
I've seen guys do it with ported e7 heads, ported cobra lowers, old alphabet cams with staggered rockers. Like stated the heads need to be shaved to bring the compression up with more rear gear and a decent c4 converter. Tested and proven football in the rear coil and 4 cylinder front springs. There will need to be a bunch of weight ditching as well.
I had a set of ported e7 heads on my 347. They had larger valves also. People said they wouldnt fit but the 2.02 and 1.60 valves did fit. I have no idea exactly how it was done ( the machine shop did all that stuff ). Those heads lasted me years with a port matched cobra lower. They were on a 306 nitrous car first. I'm not saying they were the best....but they worked better than untouched factory heads.
My machine shop bill was almost half that 1500 budget 20 years ago.
All us old guys know that there were a few people that got 5 speed ( almost stock ) mustangs to run 12.5s
My friend had one of the first street foxes to go 8.90s best of 8.62 back in 98 or 99. Those were the days, man. The good old days of junkyard 460s and 429s. There wasn't a safe old lincoln or work truck anywhere in the tri state area.
Disclaimer; I'm not a hard core drag racer... I've only ran test and tune and street style races. There are some real dedicated racers here. What would you guys direction be regarding the 12 verses 12.5 aim ?
You'd have to have more power than it takes to run a 12 flat to be consistent. If you have a day where you have traction issues...or launch issues you need to have a little power on tap to get back to that low 12. If the bracket class stops at a 12.00 you'd be crazy to want that to be your aim. Dialing in at 12.50 would be the safest way ( I would think ). That way you have some time to overshoot without being kicked out that class.
Now, if the young guy wants to get the car to 12.5s....that's a bunch cheaper than low 12s consistently.
I've seen guys do it with ported e7 heads, ported cobra lowers, old alphabet cams with staggered rockers. Like stated the heads need to be shaved to bring the compression up with more rear gear and a decent c4 converter. Tested and proven football in the rear coil and 4 cylinder front springs. There will need to be a bunch of weight ditching as well.
I had a set of ported e7 heads on my 347. They had larger valves also. People said they wouldnt fit but the 2.02 and 1.60 valves did fit. I have no idea exactly how it was done ( the machine shop did all that stuff ). Those heads lasted me years with a port matched cobra lower. They were on a 306 nitrous car first. I'm not saying they were the best....but they worked better than untouched factory heads.
My machine shop bill was almost half that 1500 budget 20 years ago.
All us old guys know that there were a few people that got 5 speed ( almost stock ) mustangs to run 12.5s
My friend had one of the first street foxes to go 8.90s best of 8.62 back in 98 or 99. Those were the days, man. The good old days of junkyard 460s and 429s. There wasn't a safe old lincoln or work truck anywhere in the tri state area.
Disclaimer; I'm not a hard core drag racer... I've only ran test and tune and street style races. There are some real dedicated racers here. What would you guys direction be regarding the 12 verses 12.5 aim ?
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