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2.76 or 2.94 for turbo car? #1429231 05/02/13 03:26 PM 05/02/13 03:26 PM
Joined: Sep 2009 Posts: 928 NC S SLOW67 OP super stock
SLOW67 OP super stock S Joined: Sep 2009 Posts: 928 NC	Finally getting back around to working on my Valiant and I'm planning on changing gears sets soon since my old handy work has made my 3.55 whine I want a better gear for cruising and I have considered a 2.76 but with the 28" tires when I'm at the track I'm alittle worried about making my 60' worse than it already is. Would you go with a 2.94 or a 2.76? I plan on doing drag week next year when my 360 is in the car so I need a good highway gear that won't sacrifice too much at the track. It will also be getting a powerglide more than likley this winter with a transbrake so I should be able to spool pretty good off the line.

Re: 2.76 or 2.94 for turbo car? [Re: SLOW67] #1429232 05/02/13 04:15 PM 05/02/13 04:15 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: Finally getting back around to working on my Valiant and I'm planning on changing gears sets soon since my old handy work has made my 3.55 whine I want a better gear for cruising and I have considered a 2.76 but with the 28" tires when I'm at the track I'm alittle worried about making my 60' worse than it already is. Would you go with a 2.94 or a 2.76? I plan on doing drag week next year when my 360 is in the car so I need a good highway gear that won't sacrifice too much at the track. It will also be getting a powerglide more than likley this winter with a transbrake so I should be able to spool pretty good off the line. I dont think your gonna see any difference of those 2 gears... Scott on here with the 62 4 door with the turbo has a 2.76 in his car now but I dont recall what his 60' is and I dont know what pressure he leaves at... all I know is its still set up pretty low(if I recall he maxes out at 10psi)

Re: 2.76 or 2.94 for turbo car? [Re: SLOW67] #1429233 05/02/13 04:18 PM 05/02/13 04:18 PM
Joined: Jan 2003 Posts: 1,883 Northern OH R rapom top fuel
rapom top fuel R Joined: Jan 2003 Posts: 1,883 Northern OH	I have a 68 charger with 2.94's in it with a mild Jeff Patterson built stroker 408. Took it to the track once and ran a 13.28 shifting into drive through the lights. I would go with the 2.76's since you have such a light car. I still think I'm running to many rpm's at 70 mph on the highway.

Re: 2.76 or 2.94 for turbo car? [Re: rapom] #1429234 05/02/13 06:00 PM 05/02/13 06:00 PM
Joined: Nov 2004 Posts: 3,619 Norwich CT USA Defbob master
Defbob master Joined: Nov 2004 Posts: 3,619 Norwich CT USA	I would find a set of 3.23's. My Cutlass with the factory 2.76's and my twin turbo 383 Chrysler, had a 2.00 60'. Grant it I did not build boost staging, I left off idle.

Re: 2.76 or 2.94 for turbo car? [Re: Defbob] #1429235 05/02/13 07:18 PM 05/02/13 07:18 PM
Joined: Apr 2010 Posts: 1,049 ohio A all spooled up super stock
all spooled up super stock A Joined: Apr 2010 Posts: 1,049 ohio	whats your car run and how many pounds of boost

Re: 2.76 or 2.94 for turbo car? [Re: all spooled up] #1429236 05/02/13 08:53 PM 05/02/13 08:53 PM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	I'd think 3,23's would be your best bet. [IMG]http://i66.tinypic.com/pui5j.jpg[/IMG] Coming soon!!!!

Re: 2.76 or 2.94 for turbo car? [Re: Mr.Yuck] #1429237 05/02/13 09:45 PM 05/02/13 09:45 PM
Joined: Sep 2009 Posts: 928 NC S SLOW67 OP super stock
SLOW67 OP super stock S Joined: Sep 2009 Posts: 928 NC	Ive only had it on the track once and ran a dismal 8.56 in the 1/8th but it went 90mph. That was on pumpgas with a bad tune on 8-9lbs. Now that my tune is better I have ran 18lbs on 100ll avgas but only on the street. My 60' sucks because I cant spool until 100ft out so I havent been back to the track until I get a tranbrake. I would like to try 3.23's but I think my highway rpm is still going to be too high. I only turn this motor 4700, it likes to be shifted like a diesel lol. My 360 will turn alittle more but will still be limited due to iron heads.

Re: 2.76 or 2.94 for turbo car? [Re: SLOW67] #1429238 05/03/13 09:36 AM 05/03/13 09:36 AM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	Maybe you should fix the 4700 rpm thing 1st. A bone stock 318 2bbl should take 5200+.

Re: 2.76 or 2.94 for turbo car? [Re: Mr.Yuck] #1429239 05/03/13 11:18 AM 05/03/13 11:18 AM
Joined: Sep 2009 Posts: 928 NC S SLOW67 OP super stock
SLOW67 OP super stock S Joined: Sep 2009 Posts: 928 NC	It will turn 5500 no problem but with everything being 100k mile stock parts with this much boost I've stayed very conservative with the rpm. Another reason I keep the rev's low is that I sized my wastegate too small and I get boost creep around 4200 and it gets worse with rpm. I've got to add another wastegate to solve that. I built myself into a corner when I installed this wasetegate and didn't leave enough room for upsizing so a second wg is my only option right now.

Re: 2.76 or 2.94 for turbo car? [Re: SLOW67] #1429240 05/03/13 12:12 PM 05/03/13 12:12 PM
Joined: Dec 2006 Posts: 235 Tucson AZ. RADAMX enthusiast
RADAMX enthusiast Joined: Dec 2006 Posts: 235 Tucson AZ.	I would not put a glide in there. your going to need that lower first gear with a tail gear like that. If you have any convertor at all it is going to be on it the whole time. At your power level the 3 speed is the better way to go.

Re: 2.76 or 2.94 for turbo car? [Re: RADAMX] #1429241 05/03/13 03:56 PM 05/03/13 03:56 PM
Joined: Nov 2006 Posts: 2,255 IL furious70 top fuel
furious70 top fuel Joined: Nov 2006 Posts: 2,255 IL	3.23's and a 28" tire is ~3000rpm @70mph with a street converter for reference. 70 Sport Fury 68 Charger 69 Coronet 72 RR

Re: 2.76 or 2.94 for turbo car? [Re: furious70] #1429242 05/03/13 05:07 PM 05/03/13 05:07 PM
Joined: Sep 2003 Posts: 10,645 Houston, Tx A AlexP I Live Here
AlexP I Live Here A Joined: Sep 2003 Posts: 10,645 Houston, Tx	Has anyone here run 2.76-3.23 with a cent supercharger? My Build thread: Let the hemi swap begin! 1968 wanna be pro touring whatchamacallit with some fancy stuff and a new roof skin.

Re: 2.76 or 2.94 for turbo car? [Re: AlexP] #1429243 05/03/13 05:24 PM 05/03/13 05:24 PM
Joined: Sep 2009 Posts: 928 NC S SLOW67 OP super stock
SLOW67 OP super stock S Joined: Sep 2009 Posts: 928 NC	My buddies mudstain has a V2 cent. and he ended up with 4.10's to get his combo to work He started with his 3.27 from when it was a turbo car and finally moved to a 3.73 then 4.10. Kinda backwards I thought but it worked for him and he's alot smarter than me lol

Re: 2.76 or 2.94 for turbo car? [Re: SLOW67] #1429244 05/03/13 05:33 PM 05/03/13 05:33 PM
Joined: Sep 2003 Posts: 10,645 Houston, Tx A AlexP I Live Here
AlexP I Live Here A Joined: Sep 2003 Posts: 10,645 Houston, Tx	I'm trying my best to avoid buying a Viper T56. I've got a Novi 1500 for my 6.1 Hemi and I really want to just run my 833 with a 3.23 and leave it alone for a while. It should make 600rwhp on 6-8 psi from what I've seen similar combos do. My Build thread: Let the hemi swap begin! 1968 wanna be pro touring whatchamacallit with some fancy stuff and a new roof skin.

Re: 2.76 or 2.94 for turbo car? [Re: AlexP] #1429245 05/03/13 06:44 PM 05/03/13 06:44 PM
Joined: Jan 2008 Posts: 4,255 Canada WO23Coronet master
WO23Coronet master Joined: Jan 2008 Posts: 4,255 Canada	Don't turbo cars love high load off the line to spool the turbos (build boost), meaning tall gears and conservative convertors? Put in a 2.76 and see what it does. I've read where guys kept putting in taller gears in turbo cars and kept going faster

Re: 2.76 or 2.94 for turbo car? [Re: SLOW67] #1429246 05/03/13 06:51 PM 05/03/13 06:51 PM
Joined: May 2003 Posts: 6,562 Downtown Roebuck Ont Twostick Still wishing...
Twostick Still wishing... Joined: May 2003 Posts: 6,562 Downtown Roebuck Ont	Quote: My buddies mudstain has a V2 cent. and he ended up with 4.10's to get his combo to work He started with his 3.27 from when it was a turbo car and finally moved to a 3.73 then 4.10. Kinda backwards I thought but it worked for him and he's alot smarter than me lol Turbo engines require exhaust heat to make boost. Superchargers require RPM. To get heat you need to load the engine. I'd go with the 2.94 and a converter that will at least let the turbo start to spool. 3000 rpm? Whatever you think you are losing on your short time you will make up for on the big end if it's making any power at all. EDIT: I just saw that you are stepping up to a 360. If you are going to lay on the boost, go with the 2.76. If it runs 9's who cares what the 60' is. Kevin Last edited by Twostick; 05/03/13 06:56 PM.

Re: 2.76 or 2.94 for turbo car? [Re: AlexP] #1429247 05/03/13 10:29 PM 05/03/13 10:29 PM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	Quote: Has anyone here run 2.76-3.23 with a cent supercharger? Alex, it depends on your set-up. Turbo works different. The S/C is going to be "on" as soon as you hit it and will build boost until you lift. You might even want 3.55's. If you run a 2.76 w/ a stick It might be a dog out of the hole. You won't have any boost until the engine is under load. So when you bring the rpm's up to say 5k you will be at 0 boost then drop the hammer, the 2.76's will drop the rpms too low I think to create decent boost His turbo and the auto will load up the convert and bring up the boost before launch.

Re: 2.76 or 2.94 for turbo car? [Re: Mr.Yuck] #1429248 05/04/13 12:05 AM 05/04/13 12:05 AM
Joined: Jan 2005 Posts: 3,635 Oakland, MI D dizuster master
dizuster master D Joined: Jan 2005 Posts: 3,635 Oakland, MI	As mentioned mine has a 2.76. It's only been out once but leaving on 1~ 2 psi, it went 1.69 60 foot. I think it will 60 ft even better thus year for sure. That being said, I would not run the powerglide with a 2.76. 3.55 at least, or maybe even 3.73. Remember 2.76 x 2.45 =6.76 ratio. 1.82 x 3.55 is only 6.41.

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