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Discussion Starter · #1 ·
I've built a 418ci, 12.5:1, Scat forged crank, 6.2" H beam rods, JE flattops, AFR205 heads, comp solid roller 248/254 @ .050 .614/.621 110 center, victor jr, and mighty demon 825 cfm carb, the car put 475HP 528TQ to the wheels through a C4 and pushed it to a 11.17 @ 124mph my question is this. I think the block is the weakest link and I want to spray the motor with a dual stage direct port & plate system. What do you estimate the killing point of the block to be?
 

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The nitrous will be the killing point most likely. 100 HP will be ok, but when you get tired of running 10's (and that combo SHOULD be faster than 11-teens assuming you're getting any kind of traction)...150 will be more fun. Then 200. Then 250, IF it makes it that far.

Sounds like a helluva lot of fun though! Go beat on it...kick some butt...and save up some $$$ for a spare engine.
 

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Biggest thing is having it tuned correctly and conservitivly. A stock block at any thing over 550 hp is a ticking time bomb, but with that said No Guts, No Glory !!!

you didn't post much about you car but I'm guessing their is more in it than a low 11' maybe try some more tweaking and tuning?
 

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Discussion Starter · #4 ·
The car is a 67 mustang w/ stock suspension and slapper bars cranked up real tight. A locker, 3.55 gears, 26x10.5 MT dot slicks, a very mildly built C4 that I have to let off to shift and a teeny weeny stall. The trans and stall are definately my next upgrades. I'm pretty sure it has high 10's in it. It's only been down the track 4 times.
 

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I'd work with tuning it and playing with the suspension before I hit it with some juice. Sounds like your still shaking everything out and I wouldn't get in a hurry.
 

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I dont think it is a time bomb with 550 hp.... remember the 69-74 351 blocks are as strong as a ford sportsman 351.. if tuned right they can handle a good amount of power.. I made 752 rwh with a stock block 393 ( 74 block, unfilled ) I ran it all season long that was 513 at the wheels all motor then a 250 plate... I ran a few times with a bigger tune 350 jets and it made 837 at the wheels... it went consistant 9.30'[email protected] on drag radials


How much do you plan on spraying and why plate and fogger?
 

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Discussion Starter · #7 ·
I don't really know why other than I think they look really cool...call me a poser I guess..what kind of n2o system were you running?What did your car run NA? What trans?
 

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Like I said, No Guts, No Glory !! LOL

Sometimes they last forever, sometimes the break the first pass............How lucky do you feel !!
 

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They usually go POP right after you've made your fastest pass ever.

(ask me how I know)...........:>)
 

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OK...... How do you know ??? LOL
 

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they make main girdle and velly girdle kits which help your block from splitting in half. i'd do that before you juice it. a little $now or more later
 

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Is it filled or unfilled?? What year is the block?? the 69-74 blocks are pretty damn strong for being production pieces. In the 80's, they made them thinner to reduce weight, this is evident when you compare a mid 80's block to an early block and look at the main webbing.
The early blocks have thicker mains that extend up through the cam journal area, the later blocks have this area all thinned out.

I've seen a production 2 bolt early Windsor block on the dyno reach nearly 900 horsepower!! It was filled to the water pump holes, had ARP studs and a billet steel main cap brace.
 

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On 2006-12-10 17:22, xray wrote:
they make main girdle and velly girdle kits which help your block from splitting in half. i'd do that before you juice it. a little $now or more later
All those parts do is help keep the parts in one pile. They don't add squat to a stock block, ESPECIALLY the valley crap.

You won't know when, but you'll suspect when it starts dripping water in an odd fashion (last 347 I saw go) or maybe pick up a slight vibration with a water drip (last 302 that busted a 10 lb chunk off the front which included the oil pump). None of the last half dozen stock blocks I've seen die this year had NOS anywhere near them. Spray and pray!
 

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The first little 'throw away' 357 engine I 'literally threw together' out of spare parts, lasted ONE season. On the first run of eliminations on the last race day (6 years ago), the engine grenaded during one of my 8 grand burnouts (ran 5.67 gears back then), (came in the car, and just was too lazy to change them out at the time).
Anyway, #7 piston decided to let go just as I was coming out of the burnout box. I thought I had punctured a slick, or something. Car went side to side. No noise, engine was still running. I shut it down. HUGE mess. Hole in pan/block/big mess.
Anyway, I had JUST run my best on the motor, 11.009, and was hoping for a 10 second pass, but OOOPS. (that's how I know)........Been there, done that.....:>)
 

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LOL !!! That Guts !!!
 

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CKelly is correct, the "valley extra's" only add weight to the engine. Nothing "added on" will stop a block from tearing in half. It's all about the micro torque pulling the two halves apart with every rotation of the crank. The more base material in the webbing, the longer it takes the micro torque to do it's damage. More HP accelerates this issue by magnatudes higher.... The same micro torque that twists your driveshaft into multiple spirals if you use it long enough.

About your setup Mr. Bottlefed, do you run with open exhaust, or a closed muffler system?

If it is not an open exhaust, you can easily pick up 1/2 a second by going to open exhaust without adding any more power to your engine. Looking at the photo of your car, it would seem that you have a traction / gearing problem, or you will have a traction problem if you add more power...... You should be in the middle 10's right now as is.....
 

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Discussion Starter · #17 ·
3" exhaust, into spintech race series mufflers dumped befor the rear axle (don't do much silencing) 26X10.50 w/ 3:55 gears. The trans is the current weak point in my combo. It comes out of the hole like a pussycat then I have to let off a little for the trans to grab 3rd. Saving up for a serious race trans w/ a break, & 4000ish converter! Hope to put it into the 10's without spray.
 

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with the correct tranny and converter its 10's NA no prob with that mph. If you stay NA you could run more gear with a taller tire and pick up traction and ET.

Very badass stang btw




_________________
Tim

81 Mustang Coupe
351W/AOD 12.13 111.7
budget 87 octane street and highway driver

<font size=-1>[ This Message was edited by: qtrhors on 2/1/07 1:29am ]</font>
 
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