GM Truck Club
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 5 of 5
  1. #1
    Jr. Mechanic
    Join Date
    Aug 2006
    Wesley Chapel, Fl

    Default ok you guys i need help

    ok i am ready to get the engine upgraded from heartbeat of america to a beastly bowtie but i

    ok so i discovered there is a company that retrofits LT1 Intakes to fit standard 350 blocks now what im gonna do is i am going to get one of them. here is there website now the exhaust is going to have to be completely redone but idk this is the sound im definitley trying to get ( can i get that rumble without that 282 cam in there bcuz i like my gas mileage. i just love that rumble. and also im looking at how to fit LT1 Aluminum heads and then rebuild them with 1.6 roller rockers. anyone know anyway i can keep this going. without putting spray. i wanna prove to ppl trucks can be fast too. and btw i do not want spray. just all motor is what i want
    Last edited by 89suburban350; 08-01-2007 at 11:29 PM.

  2. #2


    Ether my STML is getting worse or you also need help writing you posts, don’t take that personal, I have problems reading my own posts.

    Anyway I will try to answer what I think was your question.

    If you increase intake,(air/fuel mixture), you need to also increase exhaust flow, and cam duration for increase in HP.

    But then I have been known to be wrong, ask anyone.

    Technology is great, when it Works,
    And one Big Pain in the Ass When it Doesn’t.
    Detroit Iron Rules, All the Rest are Just Toys.
    94 GMC Burban, 5.7L (350), 4X4, Auto
    86 GMC Burban, 350, 2 WD, Auto
    79 GMC pickup plow truck, 400, Full time 4X4, Auto
    86 Pontiac Fiero SE, 2.8L, Auto, only mid engine American car
    See a Pattern yet?

    15 year GM assembly line worker.

  3. #3

    Join Date
    Jun 2006
    River Ridge Louisiana-4 miles W of New Orleans-didn't flood-water stopped 800 yards away.

    Default Good mpg + lopey idle not possible-overlap,misses makes lopey

    I don't know if it is possible to get the lopey idle and good mpg(like those old muscle cars with lots of cam and lots of compression).
    The old muscle cars had fairly radical cams with lots of overlap.The engines were nearly "killing/slowing" between cyl firings,and they were sending lots of fresh intake charge out the still open exhaust valve(poor mpg).They also had lots of misses because of the overlap(there was plenty of burned gases in with the fresh charge at low RPMS-so it would miss a lot..I'm not sure if the firing order had anything to do with it, but it might.
    Now engines have almost no overlap(intake opening while exhaust still open).Valves can be opened much more quickly(better springs, better cam ramps etc),so they don't have to be opened early with all the overlap.
    I might be all wet about this,so take it with a grain of salt.Don't think you can get that great idle,and good mpg.(you might try to drop the idle until it barely runs-that might help a little)
    I haven't heard a lopey idle on a newish car in many years.The 11/1 compression probably played a part also(slowing it down).Some of those muscle cars had kinda' light flywheels that made them sorta slow down between firings.Firing order might have been different also.
    PS Yes,they sounded cool.Not as good as current motors in any respect, but they sounded cool!!

  4. #4
    Jr. Mechanic
    Join Date
    Aug 2006
    Wesley Chapel, Fl


    yea tru... btw yea it was 1:30 at night when i wrote this post so i was kinda of not all there

  5. #5
    Sr. Apprentice justcuz's Avatar
    Join Date
    Aug 2007
    Alta Loma, Ca.


    You can get a mild lope out of a 415 int and 430 exh cam that was stock in a 89 Camaro 305 H.O. 5 spd and the same cam was used in a 350 auto combo in the same car. I have that cam in my 68 Chevelle with a 350 with 8.5 compression ratio and it sounds pretty good through dual exhausts. It also has good manifold vacuum and low end. Check out most cam manufacturers and they should have one. If not go to TRW, they manufacture replacement cams for almost every Chevy ever made.

Similar Threads

  1. Ok guys help me out.
    By Duncan_Z71 in forum Lifted & Offroad Suspension
    Replies: 11
    Last: 03-05-2010, 06:57 PM
  2. What do you guys think?
    By bigburb in forum Chevy Truck Accessories
    Replies: 16
    Last: 02-04-2010, 07:12 PM
  3. Hey guys...
    By STS_Silverado in forum Member Introductions
    Replies: 13
    Last: 02-02-2010, 07:48 PM
  4. Hey Guys
    By Z71 Coltman in forum Member Introductions
    Replies: 13
    Last: 02-02-2010, 07:18 PM
  5. What do you guys think?
    By 2ToNe04 in forum Audio, Video & Gadget Tech
    Replies: 13
    Last: 08-31-2009, 10:27 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts