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  #16 (permalink)  
Old 07-14-2013, 08:38 PM
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Just change 1 thing @ a time,ck for improvement,then,go to the next thing.If you throw several things in & performance starts to decline instead of improve,you don't have to go back thru several changes to pin it down.

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Old 07-15-2013, 06:46 AM
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Not trying to be mean or anything but looking at your build specs and doing some calcs and then applying them to the real world......that is a 300hp-325hp tops, around 5000rpm, 325tq give or take around 3500rpm, at the crank 355 you built. The weight and times sound pretty close to real world too. There is nothing wrong with that at all. You just have to be realistic.
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Old 07-15-2013, 06:59 AM
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Quote:
Originally Posted by steeny View Post
Not trying to be mean or anything but looking at your build specs and doing some calcs and then applying them to the real world......that is a 300hp-325hp tops, around 5000rpm, 325tq give or take around 3500rpm, at the crank 355 you built. The weight and times sound pretty close to real world too. There is nothing wrong with that at all. You just have to be realistic.
That's my problem. I always set goals that are not realistic.
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Old 07-15-2013, 10:59 AM
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Originally Posted by Slammedsi View Post
That's my problem. I know the cam is alittle on the small side and going ti a 750cfm carb wouldnt hurt. Other thwn that I don't know where to go from there. The motor seems to really run well. Just not as well ad I had hoped.
You need to know the speed at the end of the quarter. IIRC the speedo isn't working but you can use various smart phone apps to determine the speed, some are free.
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Old 07-15-2013, 03:55 PM
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Originally Posted by F-BIRD'88 View Post
Your goal of 400 real crank horsepower is not unrealistic, you just have the wrong parts for that.
And got baited by Tech and his dyno sims.

Look at the edelbrock performer rpm crate engine. It is rated at 410-420 HP.
You can improve on thiat too.
But you need a real deal 3500-4000 stall lock up converter and big big gears for 30" tall tires. (4000#+truck(
Big carb. true 10:1cr This heavy truck is very heavy. it really needs a 500+HP engine to go fast.
(supercharged 350) You bought a bunch of 350hp parts.

The heads are good once sweeteneed up. Your cr is probabily not what you think. ( piston deck height, true chamber volume.

www.converter.com
www.converter.cc
A good real deal high stall w lock up converter for this trans is not cheap.

the 105F temp don;t help engine power. Go to the track and get a power performance baseline. Then weight the truck.
i bet its over 4000#
. Now you have something to work from and can calculate how much power required for X ET MPH from this slug truck. And can make some informed decisions Goals /budget--reality.

I had a few board members and a local machine shop help with calculating the compression ratio. The only thing that wasn't checked was if the new heads had true 64cc Chambers. 9.99:1 was what it came out as being that the heads are true 64cc. Changing to a quality stall in the 3500-3800 range is my first priority.

Can you recommend a good rear gear ratio for this setup. The only track within quite a few miles is an 1/8 mile track. So my goal of a 13.00 is about a 8.30 range in the 1/8. If all im going to run is the 1/8 mile then would going to maybe a set of 4.88's work?

The truck with me in it and a full 12 Gallon cell came in at 3720lbs

Last edited by Slammedsi; 07-15-2013 at 04:02 PM.
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Old 07-15-2013, 04:32 PM
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Besides the rear gears, the trick to good drag racing ET (especially 1/8 mile) is in the first 60-100 feet. If you hook really good, the ET will improve more than just the amount of 60' ET reduction. In some cases you'll see 1.5 times the 60' reduction in the quarter mile. In other words, if you improve the 60' time by, say, 0.4 seconds (which is quite a bit of an improvement- just using as an example), the quarter mile ET could improve as much as 0.6 seconds (0.4 x 1.5 = 0.6).

You have plenty of room for rear tires, which is good. How well the truck is balanced, weight distribution-wise is also important. Obviously you want more weight to the rear for best traction- this is one reason guys put the battery in the trunk or bed. But some trucks are very light in the rear. And you need good weight transfer to the rear, which can be done by tweaking the suspension and shocks.

Books have been written on this. Some real good info written by one of the founders of the Ramchargers, Billy Shope, can be seen here and here. Some of it is pretty advanced, but it can be deciphered.
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Old 07-15-2013, 06:57 PM
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Originally Posted by cobalt327 View Post

You have plenty of room for rear tires, which is good. How well the truck is balanced, weight distribution-wise is also important. Obviously you want more weight to the rear for best traction- this is one reason guys put the battery in the trunk or bed. But some trucks are very light in the rear. And you need good weight transfer to the rear, which can be done by tweaking the suspension and shocks.

Ive got the 12 gallon cell in the middle at the rear of the bed. Along with the nitrous bottle and the Battery. ive got a set of 295-65/15's Mickey Thompson ET streets which come in at 30.10 tall, and a set 29-4.5/15 ET street front runners. I guess making the trip to the track (55 miles away) is the best bet before i start making changes.
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Old 07-15-2013, 07:43 PM
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I agree- getting a solid baseline from which to work from will allow you to see exactly what effect the changes you make are having on the performance in subsequent runs. Pain to have to drive that far, but it'll be worth it in the end I believe.
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Old 07-15-2013, 08:08 PM
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OR.... You can just pull it,ship it to me & just start all over from scratch !!! I'll find it a happy home !!! LOL.
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Old 07-16-2013, 05:58 PM
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"If you run a high 13/low 14 in a 4000 pound truck with a 600 cfm carb,thats haulin!"

Pretty much my first thought.....

Sounds pretty good for your combo, It sounds too me like you need more heads, more cam, more carb, more headers ect.
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  #26 (permalink)  
Old 07-16-2013, 06:14 PM
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Originally Posted by xxllmm4 View Post
It sounds too me like you need more heads, more cam, more carb, more headers ect.
At 1,400.00 including gaskets for the heads I surly hope I don't need a better set of heads, Or have them cleaned up for that matter. The headers are just a set of small primary cheepies. I agree on the cam. definitely going with a full solid roller this time around.
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Old 07-17-2013, 08:45 AM
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What about a set of Caltracs bars and springs? I think their traction bar kit for trucks is still under $400. There are how-to's on the web to make your own Cal-Tracs, but $400 is cheap insurance especially if you're not a structural welder. If you DO make them, don't use cheap agricultural-grade parts.
As been noted before, you're a little numerically low on the rear gear, especially with the 30" tire. The taller the tire it effectively drops your rear gear ratio.
If you want a very good converter for a street strip ride; call "Freakshow" in TX. Not super high end like Coan etc; but better than the consumer grade stuff in the catalogs and a reasonable pricetag.
Maybe you and a buddy could go in on a GTech; used ones are cheap, and it may not be Tag Heuer accurate, but it'll be consistent. Even cellphone GPS will give you mph.
If you can borrow a set of 28" tires, it'll help some (assuming they're not dead).
Thats a big hood, think about a glass one. It wont be a lot, but every little bit helps.
Have someone videotape your launch. and put a chalk mark on the tire (shoepolish; what have you)
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  #28 (permalink)  
Old 07-19-2013, 06:42 PM
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I don't think you realize how heavy 4000lbs is. It takes a lot of power to move that. You're making around 350 crank hp, so like 300 at the wheels. 14's is pretty darn good for what you have. You need forced induction or shed a bunch of weight to make it into the 13s
You should get it dyno'd as it sits right now. Its like $60 and hour or something, and its well worth it. You can get it tuned perfectly and make sure you're getting every drop of what the motor can give.
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