Where did I go wrong? Other than being a cheap ***

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1/8 mph is 75 at the stripe 1/4 was 90. I shift at 5500 and shifting from 2nd to third I felt her slow down right around 5000 so I started shifting her a little quicker going into 3rd
 
get some 26x10 maybe even a 26x9 slicks. the 26" tire height is the key here. should still hook well and be like you put in a lower gear(4.56)
The temp you posted is extreme! it must be Celsius not fahrenheit LOL
Maybe borrow some street tire in the 25 to 26" height and see if they will hook....just might. It has a pos in it right?
 
I digress, this is first!!!
SLOPAR72 said:
take some of the paycheck to the tool store and get you 3 things......

1-Vacuum gauge
2-Leakdown Tester
3-Compression Gauge

Start there and make sure you have a solid mechanically sealed motor. It's my life`s broken record when I state what's above.
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mechanic190 said:
1/8 mph is 75 at the stripe 1/4 was 90. I shift at 5500 and shifting from 2nd to third I felt her slow down right around 5000 so I started shifting her a little quicker going into 3rd
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Assuming the tune is pretty good, nosing over at 5000 means you need more cam or more compression or both. 5000 in 2nd gear is 65 mph or so. There is no way you should be feeling this at such a low mph. The trouble is you don't have room for more cam with the current compression; in fact you are already past optimum.
If we assume a generous Scr of 8.4, then the 275/108 cam in at 104, might get you a Dcr of 6.9and cylinder pressure of 131,at sealevel.
But at 2700ft the numbers are 6.37/118psi, and
At 7000, you are down to 5.5/97psi

So there are your problems; The weak take-off is the very low Dcr, and the weak trap is the low Scr, and the nose over,is the combination.
If you want the short answer; you are gonna need a lot more cylinder pressure.
To keep the same cam(for street manners ), the Wallace calculator suggests,for 2700 ft, a Scr of 11.5, to get aDcr of 8.85, and pressure of 181psi. Corrected to 7000ft this is Dcr 7.99/159psi
This should put the power peak up to 5200/5400, and the shiftrpm at least 1000 rpm higher(with a standard TFlite). Gear it to trap in third gear, at the power peak plus 300 to 500, depending on the rate of power fall-off,after the peak; Which for you might be 4.30s to 4.56s.
So this looks like; pistons,decking,shaving,a little bowl clean-up,a bigger carb, gears and a bigger TC. Up here that would be a solid $3000Can., if you already have an 8.75.

Now this should get you up close to a W/P of 10/1, & 106mph, and that will put you just into the 12s. If you can get the 60ft up to speed, maybe the mid 12s....To go faster will require more headwork, a bigger cam, and a corresponding increase in SCR. More money.
Altitude is always a PITA. And if you optimize for 2700 ft, then coming down to 1000 or less becomes an exercise in frustration.
For a fellow like you who is looking at operating between 1100 and 7000, turbocharging becomes very attractive. And the good news is your engine is already set up pretty close for it. The turbo install might cost more than the number earlier mentioned, but once installed,you can basically dial in your mph, with the little knob.How sweet is that?! Just don't get too greedy,too early in the learning curve.....cuz then you get to start over.And if you buy a pre-packaged remote mount system,you get to keep driving it for the rest of the summer.
 
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The first motor I had in my stock weight Demon was a reringed 360 with a 280/.474 lift cam ,.430 gear and cheap GER convertor. It ran 8.0's in the 1/8, I think that is around 12.50's 1/4. It had 1 5/8 headers and 2 1/4 exhaust, Torker intake and 750 holley.
 
put a methanol 750 carb on it, dont let anybody tell you that your compression is too low either for it, if your using a stock intake be sure the heat crossovers are blocked till you get a good intake yo put on it, lock the dist. @ 38-40btdc, later on put a small solid cam and springs in it. btw did you use a file to fit piston ring ? these type engines are ran all the time on oval tracks and run descent for what they are.
 
mechanic190 said:
Has open headers on it. Weight loss is damn near done with not much left to lose besides fiberglass. Fuel system is a carter electric pump through half inch fuel line to a regulator set at 6.5 lbs or so. Comp says the cam works with a stock converter so I figured 2000 should be alright with it. Rpm at the stripe is around 4000 rpm in third gear
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You don't get it. 2000 IS a stock converter for a Mopar.
 
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