Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

hp

Discussion in 'The Garage' started by jeff l, Sep 27, 2006.

  1. jeff l

    jeff l 1/2 ton status

    Joined:
    Jun 13, 2006
    Posts:
    104
    Likes Received:
    0
    Location:
    New Orleans
    I have a rebuild motor that should make almost 400hp with a rebuilt 700r4. I feel like the power is not getting to the wheels. I took it to a mechanic and he said he thinks its the trans, he would not have put that trans with a moter like that. he would put a t-350 or a powerglide. I am thinking i would rather a standard.
    what is your opinion? and is very hard to convert auto to stanard?


    3.73 gears
     
  2. gmc4cw

    gmc4cw 1/2 ton status GMOTM Winner

    Joined:
    Jul 19, 2006
    Posts:
    3,907
    Likes Received:
    0
    Location:
    west chester, Pa
    I am running a 700R4 behind a 350 putting out 350hp/400lb.ft and do not have any problems. a 350 trans or powerglide are not really any stronger. a 400 would be better. is it slipping? how long ago was the rebuild? what makes you feel its not getting to the ground?
     
  3. Chevy305

    Chevy305 6 Lug 14bsf Status Premium Member GMOTM Winner

    Joined:
    Jan 23, 2006
    Posts:
    11,228
    Likes Received:
    485
    Location:
    New Hampshire
    Definately swap to the SM465, you will never want another auto ever again!!! :D
     
  4. 1979jimmy350

    1979jimmy350 1/2 ton status

    Joined:
    Mar 24, 2004
    Posts:
    3,069
    Likes Received:
    0
    Location:
    Ann Arbor Mi
    the 700 would not really be any different from a 350, the 700 is based off a 350 tranny. and besides the 700 has a better first gear ratio and has over drive and lock up clutch.
     
  5. DEMON44

    DEMON44 Low-Tech Redneck

    Joined:
    Jan 8, 2003
    Posts:
    7,232
    Likes Received:
    15
    Location:
    Okotoks, Alberta
    are you sure its a 400 horse SBC? was it dyno'd?


    are you maybe expecting something that was never really there?


    is it set up right? carb? timing?

    If something got messed you can turn a good engine into a dog in a hurry
     
  6. the beast

    the beast 1/2 ton status

    Joined:
    Oct 15, 2003
    Posts:
    535
    Likes Received:
    0
    Location:
    Providence, RI
    A 700R4 is fine. I'm running a 400+ HP 383 in front of a stock 700R4 and it'll plant your ass. If you're concerned about the transmission, there are plenty of upgrades available for the 700R4 now.
     
  7. jeff l

    jeff l 1/2 ton status

    Joined:
    Jun 13, 2006
    Posts:
    104
    Likes Received:
    0
    Location:
    New Orleans
    the trans was rebuilt the same time.
    its not slipping
    I just spent 10 k on rebuilding this truck ,and i would think 375 hp should spin the tires.
     
  8. jeff l

    jeff l 1/2 ton status

    Joined:
    Jun 13, 2006
    Posts:
    104
    Likes Received:
    0
    Location:
    New Orleans
    sorry if i sound dumb but what is SM465
     
  9. trailblazr81

    trailblazr81 1/2 ton status

    Joined:
    May 27, 2005
    Posts:
    931
    Likes Received:
    0
    Location:
    Hollister, CA
    What size tires? If your running 35's with 3.73's and a locker you may not spin 'em. And like mentioned before make sure the motor is tuned right. Also a bit off topic if you dont already have one go out and get the biggest tranny cooler you can fit!!
     
  10. jeff l

    jeff l 1/2 ton status

    Joined:
    Jun 13, 2006
    Posts:
    104
    Likes Received:
    0
    Location:
    New Orleans
    I really wish i new more about all the trans, so bear w/ me. my 700 was paired w/ a 305. no offense to people w/ a 305 but it was a fuel and a smog conscience set up. the ratio is different, or should i say perfect ratio to a 305. I now through in a high hp motor. I just wonder is it working all in sync

    I am not saying the 700 is 100% to blame, i just thought this was something to think about.

    also i forgot to say the 700 rebuild has a shift kit and i had to put a different type lock up for my converter. b/c the computer does not control it
     
  11. jeff l

    jeff l 1/2 ton status

    Joined:
    Jun 13, 2006
    Posts:
    104
    Likes Received:
    0
    Location:
    New Orleans
    30' tires
    3.73
    eaton posi
     
  12. gmc4cw

    gmc4cw 1/2 ton status GMOTM Winner

    Joined:
    Jul 19, 2006
    Posts:
    3,907
    Likes Received:
    0
    Location:
    west chester, Pa
    you should be able to roast those tires. at the very least it should bite and launch and snap your neck back. I am running 44's with 4.56/detroit and can spin the tires at will. TORQUE BABY! :bow: I can put the bumper against a wall and spin all 4 if I want. when I had boggers it wouldn't spin on dry pavement, way to much traction. what stall is your converter?
     
  13. jeff l

    jeff l 1/2 ton status

    Joined:
    Jun 13, 2006
    Posts:
    104
    Likes Received:
    0
    Location:
    New Orleans
    your gearing is also different , I have 3.73
     
  14. gmc4cw

    gmc4cw 1/2 ton status GMOTM Winner

    Joined:
    Jul 19, 2006
    Posts:
    3,907
    Likes Received:
    0
    Location:
    west chester, Pa
    yeah but your a running tiny little donuts.
     
  15. ryan22re

    ryan22re 1/2 ton status

    Joined:
    Feb 5, 2005
    Posts:
    3,368
    Likes Received:
    0
    Location:
    Irmo, SC
    What are the specs on the motor? Compression, cam timing, heads, intake, exhaust? Did you copy someone else's build that was dyno'ed at 375-400 hp, or are you just guessing?
     
  16. beastofablaze

    beastofablaze 1/2 ton status

    Joined:
    Apr 4, 2005
    Posts:
    441
    Likes Received:
    0
    Location:
    CA
    If the thing has a carb I'd bet 100 percent it's not tuned right... carbs are very tricky without experience or good equipment. I couldn't count how many dyno runs I've seen where the right tune will give you another 40 hp... timing has a lot to do with it too.

    GM4CW: What are the specs on your motor? I'm guessing bb? spinning 44's with 4.56 gears is impressive... unless your using granny gear:D
     
  17. gmc4cw

    gmc4cw 1/2 ton status GMOTM Winner

    Joined:
    Jul 19, 2006
    Posts:
    3,907
    Likes Received:
    0
    Location:
    west chester, Pa
    I don't have the specs in front of me. It puts out over 400 lb-ft of torque pretty much off idle to 4000 rpm. makes around 350 horse around 5200 rpm. redlines around 7000. It's a 350 4 bolt main originally out of a 91 vette (center bolt valve covers) then rebuilt with a wild cam. It lopes nicely.:D getting the carb and timing set right is everything. Dyno time is worth every penny. you get real numbers and can see what changes do what. I have a 700R4 so not really a granny(3.06:1) I just mash it and let it do its thing.

    Best part is I went to the guy with a set of heads, rear main seal and tins. He built it for $1600. that included the dyno runs. That was 6-7 years ago. He just sold his speed shop september 1st.:mad:
     
  18. Chevy305

    Chevy305 6 Lug 14bsf Status Premium Member GMOTM Winner

    Joined:
    Jan 23, 2006
    Posts:
    11,228
    Likes Received:
    485
    Location:
    New Hampshire
    The SM465 only the beefiest tranny ever available in GM trucks. It is not an auto, it is a stick and is amazing. Do a search on SM465 swaps, there is alot of info out there on it.
     
  19. ryan22re

    ryan22re 1/2 ton status

    Joined:
    Feb 5, 2005
    Posts:
    3,368
    Likes Received:
    0
    Location:
    Irmo, SC
    An Allison will eat a 465 for lunch. A 465 is not for everyone though.

    and...he's not a paying member, so no searching....except for google...
     
  20. mikey_d05

    mikey_d05 1 ton status GMOTM Winner

    Joined:
    Nov 23, 2004
    Posts:
    10,453
    Likes Received:
    0
    Location:
    Minnesota
    Get yer damn cover to Iowa! It's been paid for already. :deal:
     

Share This Page