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Fed need more speed!/Help me sort out combo!

Posted By: The Nutcracker

Fed need more speed!/Help me sort out combo! - 10/03/09 08:07 PM

I think the 1/4 MPH is low, the car ran on the RPM limiter a long way 7000 RPM Could it be a converter problem?
Frontenginedragster built in 1962
Cr-mo chassi 195”wheelbase
Wheight 1688 LBS/766KG with driver
Rear: 8 ¾ rear 4.10 spool
Tires:33/10.5 MT slicks 6 PSI tire pressure
Trans: TCI Long Glide Transbreak
Converter: TCI Super Street Fighter 3000 stall
Engine: Mopar 440 stroked to 498
Engine made 722HP/5800RPM 727LBF/4700RPM
4:15 stroke Stage VI heads M1 intake
1050 Dominator
Crower solid roller 319”/324”.670/.643
lobe sep 110
1/8 5.34/129.8 MPH
1/4 8.45/154.6 MP
Best 60 foot# 1.1896

Attached picture 5522492-0889437764261-Front-Engine-Dragster-440-Mopar-150-WB.jpg
Posted By: Quicktree

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 08:37 PM

why are you running a street fighter converter? thats the first area I would look at
Posted By: The Nutcracker

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 08:48 PM

It was in the car when i bought it from USA, there where a stock 440 in it that blow up on its 5 run. Replaced it with the 498.
Posted By: Dodgem

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 09:52 PM

I would put the rev limiter up to 7600 they start to limit 300 rpm early 6700 rpm is only 149.00 mph with 7 % converter slip.
Posted By: The Nutcracker

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 10:02 PM

Engin made most horsepower at 5800RPM, i would rather not rew it to high.
Posted By: Quicktree

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 10:10 PM

what was the 60'
Posted By: The Nutcracker

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 10:24 PM

best 60 foot# 1.1896
Posted By: jamesc

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 10:31 PM

imho running it on the limiter is probably worse than letting it turn past 7k. i understand you not wanting to turn it fast but banging on the crank with the limiter isn't a good idea either. peak HP at 5800 sounds a little slow i would think it would peak higher. i know you've had problems with wheelstands on launch did you get that sorted? if i recall correctly my car goes through around 7300 160ish MPH. that's with a 4.10 axle, 8" ATI Treemaster and 14x32 goodyears. i figure the engine is making around 600HP. if that engine is making over 700HP your numbers are off. as mentioned the first thing i would do is get a good converter in the car. i would expect my tires to grow more than yours but given the >700HP you should be running over 160MPH. if the engine does in fact peak that low and you want to turn it slower you may end up having to change the axle ratio.
Posted By: The Nutcracker

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 10:51 PM

The engined has been on the dyno could be a little less HP because the distributor isnt looked out, had to lower the ignition.
The wheelstand problem is solved ,im more used to it and adjusting the wheeliebars. The motor is more of a boatengine than a raceengine, unported VI heads making a lot of torque. I think that the converter may be the problem. do you now a good sourse for a PG vert. For a carpenters budget!
Posted By: Quicktree

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 10:53 PM

don't know about there but you should be able to pick up a decent pg converter pretty cheap used.
Posted By: The Nutcracker

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 10:58 PM

On the run making 1/8 5.34/129.8MPH
1/4 8.45/154.6 MPH I was shifting at 7600RPM and had the rewlimiter at 7800RPM.
Posted By: racealittle

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 10:58 PM

I went that fast with a 550+ hp 440 and a Coan 3800 convertor, 3.91 in a 1900 lb FED. I was using 6800-7300 rpm to do it. I think it's the limiter holding you back. You seem to be hooking up. More converter means you would have to rev higher. Does it feel like it's pulling all the way? I think that you could use less gear and be more successful, perhaps a 3.5 gear. I know that I was a little over geared and should have used a 3.5.
Posted By: The Nutcracker

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 11:05 PM

It pulls hard first. Could the converter be slipping?
1/8 5.34/129.8MPH
1/4 8.45/154.6 MPH
Does the difference between 1/8 and 1/4 look ok?
With the torque could I do better with another gear?727LBF/4700RPM The engine feel very strong.
Posted By: The Nutcracker

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 11:20 PM

Im of for bed! Back in the morning!
Posted By: racealittle

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 11:21 PM

I talked with Larry Sheppard back in the early '90's about gear choice for a FED. He told me 3.5 was the optimium gear choice for the kind of motor I was running. I told him I had a 3.9 and a 4.10 with no money to try anything else at the moment. Told me to use the 3.9, but the 3.5 gear would be the answer.

You have a larger motor that makes more torque and hp earlier. So I think with 32 or 33" tires a 3.5 gear would be like the 3.9 gear I was using. It got the job done, but I was not effectively geared for the last 100 feet or so. I don't think the converter is the problem. The car is light and hooks. More convertor would get you near a 1 second 60 foot or better. I never got to try my 730 hp 440 and 5600 convertor in the digger. I sold the car last April after 20 years.
Posted By: The Nutcracker

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 11:30 PM

Could the zoomieheaders hold me back? I do have a pair of alteredheaders. The engine was dynoed using regular dynoheaders.
Posted By: RodStRace

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 11:49 PM

I think what everyone is telling you is if you want the motor to be at a lower rev at the finish line, you have to change to a lower (number) gear or a taller tire. Given that 14X32 is pretty common and big, the best answer would be to change the rear gear. The converter may be slipping, and replacing it with one more suited to your combo may help in the 1/8th, but you are running out of car before you are at the end of the 1/4.
Posted By: goldmember

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 11:52 PM

The first question on my mind was the Zoomies and whether they were on the dyno. Ditch them for a good set of 4 into1's and you'll get results. I also agree that you'll be better off with a gear close to 3.5 ratio. Your combo is way off the HP/weight you stated. Converter isn't ideal but somethings killing that combo.
Posted By: Quicktree

Re: Fed need more speed!/Help me sort out combo! - 10/03/09 11:53 PM

Quote:

The first question on my mind was the Zoomies and whether they were on the dyno. Ditch them for a good set of 4 into1's and you'll get results. I also agree that you'll be better off with a gear close to 3.5 ratio. Your combo is way off the HP/weight you stated. Converter isn't ideal but somethings killing that combo.


Posted By: jamesc

Re: Fed need more speed!/Help me sort out combo! - 10/04/09 12:17 AM

the zoomies aren't the best for HP that's for sure but your numbers are way off. i wouldn't be using the zoomies either way but be careful about changing too many things at the same time you can get even more lost. assuming the engine is making close to the HP you say it dynoed at the zoomies shouldn't slow it to the point you're at. with no converter slip or tire growth 7000 rpm with a 4.1 and 33" tires should be running close to 168mph. if you're car is turning 7000 rpm and only running 155mph that converter looks to be slipping a ton. no way i'd put a 3.5 gear in it, 3.9 is as far as i would go but you've got something else going on other than axle ratio. can you borrow a decent 8" race converter off someone? when running a power glide the converter is VERY important. without actually seeing the car run in person it can be hard to give good advice but no way that engine should be turning 7000 and only running 155. here's a link to a ratio/rpm/speed calculator. this is strictly numbers with no accounting for tire growth or converter slip. http://www.markwilliams.com/calculators.aspx here's one for converter slip http://www.wallaceracing.com/converter-slip.php
Posted By: Cab_Burge

Re: Fed need more speed!/Help me sort out combo! - 10/04/09 04:32 AM

Don't be afrriad to try revving it pasr peak HP RPMs, my 518(4.300 stroke with BB Chevy rod sizes) low deck six pak motor made peak HP at 5800 RPM and peak torque at 4500 RPM. I ended up finding out the car will run the fastest by shifting it at 7300 RPM I agree on the headers the rear gear ratio and the chip, get rid of the chip and shift it higher in 1st gear and see what happens
Posted By: The Nutcracker

Re: Fed need more speed!/Help me sort out combo! - 10/05/09 08:57 PM

Thanks for your help!
Season is over .
Looking for a new converter for next year.
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