347 Header Size and exhaust Diameter

96pushrod

Mustang Master
May 15, 2018
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So you have the flat tappet version of that cam? Because there is a hydraulic roller version with the exact same duration.

I really don’t know why a shop would recommend you a solid roller cam, especially on a street driven car. You can do some badass things with hydraulic rollers nowadays.

If you want to put down decent times you need a real tire back there. Mickey Thompson or Hoosier will do for the strip. Et street is nice for road and strip use.

The strange 10 way adjustable shocks/struts with some stock springs and good control arms can be adjusted very well for the track, and ride good on the street too. You don’t need to spend crazy money for a good suspension System. The double adjustable stuff really isn’t required.
 
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TOOLOW91

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Solid roller cam for a mild street car ? My buddy just went 8.67 at 162 in his hyd roller 347 blower street car at a rental .
 

Wellzy55

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So you have the flat tappet version of that cam? Because there is a hydraulic roller version with the exact same duration.

I really don’t know why a shop would recommend you a solid roller cam, especially on a street driven car. You can do some badass things with hydraulic rollers nowadays.

If you want to put down decent times you need a real tire back there. Mickey Thompson or Hoosier will do for the strip. Et street is nice for road and strip use.

The strange 10 way adjustable shocks/struts with some stock springs and good control arms can be adjusted very well for the track, and ride good on the street too. You don’t need to spend crazy money for a good suspension System. The double adjustable stuff really isn’t required.


I currently have the hydralic roller. He had just mentioned that a solid roller might benefit me.


So today I went down to the shop I've been talking to and he kinda went over everything for me. Let me know what your thoughts are. And remember I'm on a budget and he was taking it into consideration as well lol.

A 90/10 front strut with the factory springs for now. Rear lower control arms and new urethane upper bushings with factory springs. With a 50/50 shock. He also told me I need to get a pair of 26' 10.5 Mickey Thompson bias ply slicks.

He basically talked me out of wanting all the adjustable stuff. He was saying unless you are running a 10.5 or faster you didnt really need it.

What do you think? Sound ok to your guys? He seemed to know what hes talking about.
 

96pushrod

Mustang Master
May 15, 2018
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The 10 way strange struts and shocks are less than the Lakewood’s. I’d pick the strange. They’re like $400 for the fronts and the rears combined. The one thing he did get right is the bias ply slick. Far more forgiving than a radial tire. I’d just get a second set of wheels for the track and mount the slicks on them.

Then get a set of summit racing upper and lower control arms, throw the quad shocks in the trash, put a 10.5 QuickTime Pro On in the rear and enjoy shaving a second off your current et.
 

96pushrod

Mustang Master
May 15, 2018
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One question though: why did the dyno pull stop at 5500rpm for a cam with 247* of duration at .050?

Also, where are you shifting the car at the track?
 
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Wellzy55

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One question though: why did the dyno pull stop at 5500rpm for a cam with 247* of duration at .050?

Also, where are you shifting the car at the track?


I'll definitely look up the Strange shocks and struts.

I just ordered a set of 15 × 10 rims and a set of the Mickeys Thompsons Bias Ply. They should be here in about a week mounted and balanced and ready to go. I'm excited to see how much better they are. I've never driven a car with slicks.

About the dyno pulls.
I think the guy just didnt want to break it lol.
He was in 3rd for the first pull and he said he felt he needed to be in 4th so he did that on the second pull.

On the first pull it looked like the HP was still building Significantly before he came out of it, but on the second pull in 4th it started to flatten. Not sure how to really compare those two pulls. Does it make a big difference on what gear your in?

If I have it dyno again I'll tell them to take it up to 6,500 and maybe 6,800.
 
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General karthief

wonder how much it would cost to ship you a pair
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You going to run Orlando?
Hummmm, the Stangnet.com drags...... The traveling stangnet.com drag race show..... Stangnet No Prep Night .......this could be big, I have to think about this..
Where's my coffee cup?
 

2000xp8

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I think before buying any suspension parts you should get under the car and take inventory of what you have and do not have.
Kinda odd to build a 347 and have done nothing to the suspension. But it would seem the previous owner of your car didn't operate under much logic.
One would think at least he did lower control arms.

#1 on the list is subframe connectors.
#2 should be torque box reinforcements.
I wouldn't even go back to the track without both.

I'm not so sure either that the dyno operator is going to let you dictate the rpm you goto either. Nearly 7000rpm on a stock block is a lot.
 
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Wellzy55

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I think before buying any suspension parts you should get under the car and take inventory of what you have and do not have.
Kinda odd to build a 347 and have done nothing to the suspension. But it would seem the previous owner of your car didn't operate under much logic.
One would think at least he did lower control arms.

#1 on the list is subframe connectors.
#2 should be torque box reinforcements.
I wouldn't even go back to the track without both.

I'm not so sure either that the dyno operator is going to let you dictate the rpm you goto either. Nearly 7000rpm on a stock block is a lot.

They did install subframe connectors but that's it. I didnt think I would need torque box reinforcements being that I'm only making about 325whp. But it's something I will look into. The previous owner was not drag racing it. So they didnt do much to it.

I am ordering lower rear control arms and shocks and struts for now along with better bushings. And I ordered a set of Rims and Slicks last night. I'm very limited on $$$ right now. I got laid off due to Covid-19. So once I get back to work I will do more upgrades.

What kind of 60 foot times should I realistically be looking at with the setup I will have? Maybe 1.7- 1.9? What about Et?
My best was a 13.28 with a 2.07 60foot @111 mph. I'm hoping to at least see a 12.7.
 

2000xp8

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You are removing the lower control arms anyway and the torque box kit's are cheap.
Chassis stress moves on to the next weakest place. Guys crack torque boxes with stock engines.
The subs are done, that's good, then the stress goes to the control arms which won't have rubber bushings anymore.
Then you will have a drag suspension setup which essentially changes were the forces goes.
As someone who has heavily damaged torque boxes, my question would be, can you afford not to use a torque box kit?
$1100 is what it cost me to fix back in the day.

Remember too, you made your power on a mustang dyno, and while it's no where near the potential of those heads, it's probably closer to 350rwhp on a dynojet which is used for most comparisons.
 
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revhead347

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Definitely do the torque boxes, at least the lowers. It's not how hard the engine is, it's how sticky the tire is. You're going to know the first time you drop the clutch with the engine at 6000rpms and feel your brain slosh to the back of your head that it was worth it. Launching a car on slicks is going to be like nothing you have ever felt before.

Kurt
 

Monkeybutt2000

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Definitely do the torque boxes, at least the lowers. It's not how hard the engine is, it's how sticky the tire is. You're going to know the first time you drop the clutch with the engine at 6000rpms and feel your brain slosh to the back of your head that it was worth it. Launching a car on slicks is going to be like nothing you have ever felt before.

Kurt
First launch on slicks scared the crap outta me, I thought I broke something. It was just the slicks doing their thing.
 
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Wellzy55

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You guys have me laughing over here. I cant wait to get it back to the track, and see what she can do. Hoping for 12.6 -12.7.

I was just looking up the torque box reinforcements and I'll definitely get a kit and do it all at once.

I really cant imagine me being able to launch at 6000rpm. It will really grip that good? lol. That's crazy
 

revhead347

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You guys have me laughing over here. I cant wait to get it back to the track, and see what she can do. Hoping for 12.6 -12.7.

I was just looking up the torque box reinforcements and I'll definitely get a kit and do it all at once.

I really cant imagine me being able to launch at 6000rpm. It will really grip that good? lol. That's crazy

You HAVE to rev it up to around 6000rpms before you launch the car on slicks. If you don't, it will bog, and that's how you brake stuff. If you don't leave hard enough, the car falls on it's face backloading the whole drivetrain and the weakest link tends to give. Slicks change everything. They are really hard on the car; much more so than a more powerful engine. They brake axles, they snap driveshafts, and it's like a goblin with a hammer in your transmission. You might want to do some youtube university before you go back to the track. If you do it right, at least your right front tire should come off the ground an inch or so. If you do it wrong, there's a good chance you are going to brake something. I always use the comparison of a tug of war; at one end of the rope is the power of the engine and the weight of the car, at the other end is the traction of the tire, and the rope is the drivetrain in the middle.

Kurt
 

Wellzy55

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You HAVE to rev it up to around 6000rpms before you launch the car on slicks. If you don't, it will bog, and that's how you brake stuff. If you don't leave hard enough, the car falls on it's face backloading the whole drivetrain and the weakest link tends to give. Slicks change everything. They are really hard on the car; much more so than a more powerful engine. They brake axles, they snap driveshafts, and it's like a goblin with a hammer in your transmission. You might want to do some youtube university before you go back to the track. If you do it right, at least your right front tire should come off the ground an inch or so. If you do it wrong, there's a good chance you are going to brake something. I always use the comparison of a tug of war; at one end of the rope is the power of the engine and the weight of the car, at the other end is the traction of the tire, and the rope is the drivetrain in the middle.

Kurt


I'll definitely be taking it out on the long backs roads by my house and do some practice pulls to learn it a bit. Ive been reading up on it quite a bit. Just didnt realize the slicks can really hold that good that's impressive. I was thinking I would have to launch at like 4000-4500.

So when you launch it do you just dump the clutch or do you kinda just back it off quickly? And do you roll all the way in to the throttle on the hit? Or let it roll out a little bit and start applying throttle? Sorry for all the questions. I'm just trying to learn some best practices.
 

revhead347

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I'll definitely be taking it out on the long backs roads by my house and do some practice pulls to learn it a bit. Ive been reading up on it quite a bit. Just didnt realize the slicks can really hold that good that's impressive. I was thinking I would have to launch at like 4000-4500.

So when you launch it do you just dump the clutch or do you kinda just back it off quickly? And do you roll all the way in to the throttle on the hit? Or let it roll out a little bit and start applying throttle? Sorry for all the questions. I'm just trying to learn some best practices.

You back it off quickly. It's an art. There are actually slow bleed devices that you can tune to release the clutch at the desired speed. I've never used one, but some people just can't master it. You need full throttle as fast as you can get it in there. There are all kinds of devices you can put on the car to make this work better. Most people use a 2 step rev limiter where you set the launch rpm in the ignition control, hold the throttle to the floor, and just release the clutch. A line lock for the front brakes gives you a much better burnout. You will need to do a second gear burnout to get good traction. Do a quick 1st gear burnout while the car is rolling through the water box. Then stop the car, and do decent burnout in 2nd gear. Don't go crazy; when you see consistent smoke from both tires, you are good. Literally the best way to learn how to do it properly is to find someone with experience at the track who will let you ride shotgun and walk you through the process. The best thing you can do right now while you are waiting on parts is to go to the track without your car and talk to people. Don't expect perfection on your first pass, and don't be unhappy with the results; It's going to take a little bit of practice.

Kurt
 
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revhead347

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Oh, and get a can of cheapest car wax you can find. Coat the body work behind the rear tires heavily with it, and then let it dry and don't wipe off the excess. The slicks kick off huge chunks of hot rubber up onto the body behind the tires during the burn out. The dry wax keeps it from damaging the paint, and you can just wash it off with a hose later.

Kurt
 
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Wellzy55

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You back it off quickly. It's an art. There are actually slow bleed devices that you can tune to release the clutch at the desired speed. I've never used one, but some people just can't master it. You need full throttle as fast as you can get it in there. There are all kinds of devices you can put on the car to make this work better. Most people use a 2 step rev limiter where you set the launch rpm in the ignition control, hold the throttle to the floor, and just release the clutch. A line lock for the front brakes gives you a much better burnout. You will need to do a second gear burnout to get good traction. Do a quick 1st gear burnout while the car is rolling through the water box. Then stop the car, and do decent burnout in 2nd gear. Don't go crazy; when you see consistent smoke from both tires, you are good. Literally the best way to learn how to do it properly is to find someone with experience at the track who will let you ride shotgun and walk you through the process. The best thing you can do right now while you are waiting on parts is to go to the track without your car and talk to people. Don't expect perfection on your first pass, and don't be unhappy with the results; It's going to take a little bit of practice.

Kurt

The burn out process actually has me a little bit worried lol. I dont have line lock and I've never done a burn out in 2nd. If they have that much grip how do you get them to slip and do a burn out?

I've been looking it up a bunch and it seems that I just need to rev it up high dump the clutch and go straight to the brakes and apply as much as needed to keep me in place and then slowly come off the brake and push in the clutch once you gain a little traction. Does that sound about right? And why 2nd and not 1st?

Thanks for all the great advice and tips