jack46 Posted April 27, 2004 Share Posted April 27, 2004 Didn't want to steal his thread anymore. I may go once more to track before changing to new rearend I'm debating changing the u joints just to throw them away. Is why I say may seems stupid to put new ones in then throw them away. You said how about letting me know next time you go to huntsville jack! Like to see a fellow Hybrider make a few passes.Mines going 11.6@120 1/4 around 7.6 1/8th right now.R200 and halfshafts still hanging in there(knock wood).Soon as I get Fuel pump straightened out,gonna turn up the laughing gas a little more.7.0 maybe? I'll be happy with that My theory is it is the launch that gets u joints. I am now down to 1.64 (motor) with 4.11 and if I try to spray the joints go. I feel the choices are 1. Don't juice or juice late ( 20 30 40 feet out or time delay) 2. CV joints with 200 or R 230 3. Or stronger axle like ford 9" I wanted 7.00 as well seems for my setup I can't get there without more work. I won't say you can't or won't get there, seems too many variables to say, but as 60 foots diminish the stress on the joints seems to go way up. And for low 7.'s u need a really good 60 or a HUGE motor to make it up. 2 questions where do u run 1/4, and what rear gear you have? I went to holley Blue i think it is (I suspect my stock line isn't flowing what I need, and will change it next go around and put in a 1/2" line). Seems there is no end. Nice to meet you look forward to seeing you in huntsville soon I will keep in touch Quote Link to comment Share on other sites More sharing options...
Pyro Posted April 27, 2004 Share Posted April 27, 2004 You are at the limit of Z drive train. If you want to go faster without changing parts every 2 or 3 passes then you need to to sometime major. I have never broken a U-joint but my outer stub axles and diff pins have broken many times. I'm in the same boat as you, I need to change something big. My car has run 1.5 60 foots, 6.9@110 1/8 miles, and 10.7@135 1/4 miles. And I'm also spraying N20 on top of a 350 with a 5 spd trans and MT slicks. But I'm breaking parts and don't feel the car is safe anymore. Here is an idea for your N20 system. Buy a 1 gallon fuel cell and mount it in the engine compartment (drivers side by the radiator). Then get a small fuel pump to supply the fuel enrichment to the N20 system. This way you can run racing fuel in the 1 gallon tank. 1 gallon of fuel will last longer than a 10 lb bottle of N20. And your Holley will get a little help from the other pump. One way to limit drive train stress is to reduce the "shock" when coming off the line. I use a brake line lock to hold the car in place at the starting line and let the clutch out just a little before dumping the clutch. This technique takes up the slop in the gears, U-joints, and splines before the "take off" and reduces the hammer effect when the clutch is dropped at 5000 rpms. You could also do this with an automatic trans. As for me.....I have decided to go 4 link with ford 9 inch with a 3.08 gear, th400 with a 2500 stall, and IC'ed turbos on an efi 350. A year or two project!!! Quote Link to comment Share on other sites More sharing options...
jack46 Posted April 29, 2004 Author Share Posted April 29, 2004 I have never broken a U-joint but my outer stub axles and diff pins have broken many times. I'm in the same boat as you, I need to change something big. My car has run 1.5 60 foots, 6.9@110 1/8 miles, and 10.7@135 1/4 miles. And I'm also spraying N20 on top of a 350 with a 5 spd trans and MT slicks. But I'm breaking parts and don't feel the car is safe anymore. I have heard many like you going ALOT faster...But you are right I'm at the point I think I will tub and put the Ford hate idea but sick of not trusting it and want alot more. I planned on a bigger setup sooo seems there is little choice Here is an idea for your N20 system. Buy a 1 gallon fuel cell and mount it in the engine compartment (drivers side by the radiator). Then get a small fuel pump to supply the fuel enrichment to the N20 system. This way you can run racing fuel in the 1 gallon tank. 1 gallon of fuel will last longer than a 10 lb bottle of N20. And your Holley will get a little help from the other pump. I like the idea but right now if I juice I break the jopints but yes I have been told to do that so you can run special gas for juice. One way to limit drive train stress is to reduce the "shock" when coming off the line. I use a brake line lock to hold the car in place at the starting line and let the clutch out just a little before dumping the clutch. This technique takes up the slop in the gears, U-joints, and splines before the "take off" and reduces the hammer effect when the clutch is dropped at 5000 rpms. You could also do this with an automatic trans. Well I hold it at about 1600 1800 (stall would flash to prolly ~2600) so thought I had slack out just allowed motor to get some legs so it didnt bog at line. I also am designing a NOS controller with a micro processor to enable me to set juice to whatever value i want at any RPM. Will be a nice setup should (hope) to get it done by July and will try to sell a few to get my money out of it. They won't be high dollar and have all good features (timing set back at rpm total of 30 sets) will also have same number for nos sets) As for me.....I have decided to go 4 link with ford 9 inch with a 3.08 gear, th400 with a 2500 stall, and IC'ed turbos on an efi 350. A year or two project!!! why 3.08 didnt see post but good to hear from u Quote Link to comment Share on other sites More sharing options...
Pyro Posted April 30, 2004 Share Posted April 30, 2004 Why a 3.08 gear.....I should have said 3.10 or 3.00 gear. 3.08 is a chevy ratio not a ford. I guess once a chevyman, always a chevyman. anyway.... I hope to hit 145mph in the 1/4 mile with 16 to 18 pounds of boost on a 350 or 383 cid. And, a 3.08 gear with a 26" tall tire at 145 mph will be reving the engine at 5,800 rpm (in theory). However, there will be some slippage so 6,000 to 6,200 should be the rpms at the end of the track. 6,200 should be enough. My 350 now hits the traps now at 135 in 4th gear at 7200 and it seems like too much. Maybe under extreme conditions and a lot of racing fuel and more boost then 150+ mph could be possible (6,500 rpm). But 145 is the limit at the track for cars w/out parachutes. Plus a turbo engine would like to pull on a 3.08 automatic and this combo would also make for a easy driving street machine. LOL. In theroy...... A 320 hp small block with 17 psi of boost added will make enough hp to get a 2900 lb car to 145mph in the 1/4 mile (690 hp). Even at 12 psi, a 135+mph 1/4 mile would be possible. It all depends on the power potenial of "base engine" before boost and how well the turbo is matched to the engine. Sorry, for the long and twisted answer. Quote Link to comment Share on other sites More sharing options...
jack46 Posted April 30, 2004 Author Share Posted April 30, 2004 Dang I think my heart skipped a beat thinking of that trap speed! I have almost decided I will tub and go Ford 9". I want to eliminate all possiblities, but seems few real choices and a friend has offered to help, and he has done a Z with Ford before. He is also a welder so that alone makes me lean toward it then there is availability of gears etc. What blower you running or planning on using? I presently have a 383 that may get blown or may have to destroke it since it has 400 rods and to get a crank that can take the blower want something forged and seems no one has one for 400 rods and destroking will drop me from 9.2 CR so might be best anyway. Quote Link to comment Share on other sites More sharing options...
jack46 Posted April 30, 2004 Author Share Posted April 30, 2004 oooops missed the turbo my bad Quote Link to comment Share on other sites More sharing options...
Turbo Meister Posted May 1, 2004 Share Posted May 1, 2004 I hope to hit 145mph in the 1/4 mile with 16 to 18 pounds of boost on a 350 or 383 cid. I have run 137 mph in the quarter mile with my TT383 Chevy Z at 10 PSI boost and 116 mph with 15 PSI in the 1/8th mile ( that equates close to 145 mph in the 1/4 ). I can now generate 25 PSI but I have no competition license and dont want to get kicked off the track again. With 29" tall tires, 4.11 gears, TH400-3800 stall, 137mph showed 6000 RPM at finish line. That's not theoretical thats eye-balling the tach; my set-up,anyway. Hanns Quote Link to comment Share on other sites More sharing options...
jack46 Posted May 1, 2004 Author Share Posted May 1, 2004 I wish I had decided to go this far from the get go could have avoided some expense. But then I guess that is part of the appeal the trial and error makes the journey all the more rewarding. Hanns what diff are you running I'm at a decision point since I seem to be in the unlucky group that hit problems with the r 200 early. Im leaning toward ford 9" for many reasons what is your opinion Thanks PS Just what I needed was another grey beard running fast, but then hey if it wasn't for toys what would I get to play with well hmmm that didnt sound right did it Quote Link to comment Share on other sites More sharing options...
Turbo Meister Posted May 1, 2004 Share Posted May 1, 2004 Hanns what diff are you running I have a narrowed 9" Ford. Once I got the Currie 9 Plus third member I have'nt worried about that part of the Z. A few drag-strip runs burned up the carrier bearing and clutches of the stock 9". According to Currie, the stock 9" is good for only 350 rear-wheel hp. I'm retired-it's time to play ( the faster the better )!!! Hanns Quote Link to comment Share on other sites More sharing options...
jack46 Posted May 1, 2004 Author Share Posted May 1, 2004 Hanns I have never heard of a Currie 9 Plus third member, and I thought a Ford 9" with the weight of the Z was nearly indestructable? I would like to know more are there posts here or where is the best place for me to understand the Currie setup? I don't want to change then shortly after find I didn't do the change right (can't for see all problems but I want to try to do the search before I start) Thanks for the help. My car presently weighs 2820 with my fat ass in it (I'm 220). Quote Link to comment Share on other sites More sharing options...
Turbo Meister Posted May 2, 2004 Share Posted May 2, 2004 I have never heard of a Currie 9 Plus third member, and I thought a Ford 9" with the weight of the Z was nearly indestructable? Jack, The Currie 9" Plus is just a heavy duty Nodular Iron ring & pinion housing with extra structural strengthening ribs and pinion support. The amount of torque that it is subjected to and the weight of the vehicle determines its longevity. Also, the age and general condition of the 9" is a factor in how long it survives. The lighter weight of the Z helps but My 9" was old and swap-meet quality. You would probably have better luck with a good condition stock 9" but it will not handle constant 700/800 ft lbs of torque drag-race starts. Many major drive-train specialists, Strange, Currie, etc., sell their own heavy duty R/P housings at reasonable prices. Hope this helps. Hanns Quote Link to comment Share on other sites More sharing options...
Pyro Posted May 3, 2004 Share Posted May 3, 2004 Mr. Turbo, Thanks for the gear/rpm data. I didn't consider using 29" tires, but 29's would be better than 26's as long as they fit. However, I was kind of leaning to setting up my car so driving on the street would be possible and 26" radials would look more "normal". But, 29's on the track would be much better! Your rpms at the end of the track indicate your 29" tires are growing to 32 inch at speed! I didn't consider that much tire growth in my rpm calculations. Jack, FYI, circle track guys sell used 9" diff all the time. A friend of mine recently got a pretty good deal on one. Quote Link to comment Share on other sites More sharing options...
jack46 Posted May 3, 2004 Author Share Posted May 3, 2004 Thanks Hanns I was aware of the nodular part didn't realise that's what they called it when it was part of ford diff. Pyro a guy here will sell me a 9" for $100 and $125 for different gears. He is a 4 wheeler soo I'm thinking he will be fairly reliable to deal with. Thanks for all the inputs I must say I HATE the thought of 9". But there really is no reliable solution other than that within my budget. My friend moved into his new place so still hoping end ogf month to do the change Quote Link to comment Share on other sites More sharing options...
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