Enter your username:
Do you want to login or register?
  • Forgot your password?

    Login / Register



    Page 1 of 3 1 2 3 LastLast
    Results 1 to 20 of 42

    Thread: Hot LT4 or LS1?

    1. #1
      Join Date
      Dec 2005
      Location
      Maryville, TN
      Posts
      839

      Hot LT4 or LS1?

      Has anyone messed with those Hot LT4 kits? They're advertising 425+ hp with them, but I'm a little scepticle.

      This of course, is leading to the bigger question... I'm currently trying to decide on what engine to put in my 67 camaro project. About 7 years ago I started just buying parts without really doing a lot of research into what would be best. What I ended up with is a 400 small block with a destroke kit from Speed-o-Motive to make it into a 377 (none of this is put together yet keep in mind), as well as a custom ground cam that matched the TPIS X cam (it was cheaper to have one custom ground then buy it from TPIS *L*). A set of Sportsman II 200CC heads (yeah.. I know, it was all I could afford at the time) and a plan to buy the miniram intake from TPIS that looks like the LT1's intake.

      So, keeping in mind that I've got all these parts... I really love the LT1 motors.. and am kind of thinking of getting one to convert to an LT4... or I'd really like to have an LS1 as well. The LS1's seem easy to get to make a lot of HP, but getting a used one seems like a bit of an expensive pain in the butt. The LT1's are easier / cheaper to be had, but I'm curious just how easy it is to get them making some of the big numbers the LS's are posting these days.

      In everyone's opinion... whats my best move? Keep what I've got, but obviously ditch the heads and get some sort of fuel injection setup ( a must for my project), or toss it all in favor of an LT / LS motor?

      My goal with this car is to have an awesome pro touring car that I can drive in traffic just as easily as I could take it to the track and have a lot of fun in. It's getting some sort of suspension treatment, definitely a six speed.. and who know's what else. My horsepower goals are somewhere in the 500's... or enough to get confused looks from the handful of new 'vette owners in the neighborhood.

      Thanks for all the help!



    2. #2
      Join Date
      Oct 2004
      Location
      Macon, Ga.
      Posts
      8,085
      Country Flag: United States
      First, welcome to the site Dan,
      I am from the old school and it took alot of convincing here to get me to change, however, now that I have plunged into the world of LS I doubt I ever have anything else. I own a early A-body with a LSx 6.0 with a magnacharger. Very cool package, very reliable and should do go gas mileage wise. To say nothing of the wow factor when you open the hood. I also own a 97 Camaro with a Procharger, but just not as impressed with it as I am the LS stuff. However, be prepared for more than a simple engine swap if you do change to the LS. There are issues when changing over, however, well worth the trouble.
      Bill

      Trailers are for BOATS!

    3. #3
      Join Date
      Dec 2005
      Location
      Maryville, TN
      Posts
      839
      Yeah, I've done quite a bit of reading on the swap.. and for some reason that doesn't scare me as much as simply trying to figure out what to buy .

      I see you're in Pigeon Forge... I'm actually in Maryville. Where did you end up finding your LS? The local swap meet folks are way to proud of them for my blood.

      Other then the magnacharger, what do you have done to your LS? Est. power output?

    4. #4
      Join Date
      Oct 2004
      Location
      Macon, Ga.
      Posts
      8,085
      Country Flag: United States
      Maryville, dang, small world. You know Gary Neff?
      Bill

      Trailers are for BOATS!

    5. #5
      Join Date
      Dec 2005
      Location
      Maryville, TN
      Posts
      839
      Never heard of him.... should I know him? I saw there was a group of guys got together up in Pforge last year... I'm going to have to come up there with you guys next summer.

    6. #6
      Join Date
      Oct 2004
      Location
      Macon, Ga.
      Posts
      8,085
      Country Flag: United States
      He lives there and worked on my car. Yeah, we had a blast at the get together, come on down next time.
      As far as my car goes, it has a 04 lsx that is factory rated at 345, the magnacharger adds about 130 so I should have somewhere around 475 at the crank. We plan to dyno it though in Maryville next month, then I can give you the real numbers. The engine is stock other than the blower.
      Bill

      Trailers are for BOATS!

    7. #7
      Join Date
      Jun 2002
      Location
      Long Island, NY
      Posts
      11,320
      Country Flag: United States
      Based on your goals, I'd say go with the LSX. 500hp should be no problem with a decent cam, a good set of heads (aftermarket 205cc or ported stage 2) and all bolt-ons. It'll drive real well, too. The LT1/4 are great motors, but the LS1 is the superior mill.

    8. #8
      Join Date
      Dec 2005
      Location
      Maryville, TN
      Posts
      839
      Bill,

      Where did you end up finding your LS?

    9. #9
      Join Date
      Oct 2004
      Location
      Macon, Ga.
      Posts
      8,085
      Country Flag: United States
      I have a friend in the salvage business in Georgia. He located the engine and also the 4L80. Ebay is another good source. There are several places that deal in LS stuff. There is a place close to us here actually that parts out late model F-bodies and other LS equiped cars. I will try and find their number.
      Bill

      Trailers are for BOATS!

    10. #10
      Join Date
      Aug 2004
      Location
      Dunwoody, GA
      Posts
      4,984
      Country Flag: United States
      if you decide to go with the LT motor dont buy the LT4 conversion kit. you can do better for less. besides with your power goals in mind there are parts in the LT4 kit that you want need like the cam and the valve springs. you will need the LT4 intake so that you can match it up to LT4 style heads.

      what i would recommend for an LT based motor is to get with lloyd elliot at eportworks.com or contact Bret Bauer who is sstrokerace on this board. they do very good work. personally i would go with LT4 intake matched to LT4 heads or AFR LT4 heads. the heads and possibly the intake will need to be ported. then get a nice rumpity cam from them. keep it in a 350 or 355 and make sure you have all the supporting parts like exhaust and fuel injectors. you can have well over 400rwhp with this type of setup.

      also i didnt notice if you said you have an LT block. you can not put LT heads on a non LT block. the block is unique to the LT line up and the heads will not work on a gen I sbc. however you can modify Gen I heads to work on the LT blocks. that usually requires a sheetmetal intake to work though.
      Trey

      "The early bird may get the worm, but the second mouse gets the cheese."
      ~ Jon Hammond

      1979 WS6 Trans Am stock LT1/T56 drive train out of my Formula. BMW M-parallel rims. C5/C6 brakes

      build thread https://www.pro-touring.com/showthre...ghlight=begins

    11. #11
      Join Date
      Dec 2005
      Location
      Maryville, TN
      Posts
      839
      No, it's a non LT block. It's a 400 4 bolt main, small block. And my plan was to either build that (in destroked form), or ditch the whole thing all together and either go LS or LT.

      The other thing I was concerned about, the numbers that all the magazines are posting for the LS motors are awesome numbers, but they are WAY up in the RPM range for normal street use... which I guess is a okay if you run a really high rearend gear.. but for a mostly street / some race goal in mind, seems kind of impractical.

      Can anyone speak to that?

      And you said keep it 350 or 355? What's your thinking here?

      Has anyone tried this 363 that Speed-o-motive is selling?
      A.K.A: That bald guy
      Find me on Facebook or my personal website.

      - 67 Camaro: Current Project Car

    12. #12
      Join Date
      Aug 2004
      Location
      Dunwoody, GA
      Posts
      4,984
      Country Flag: United States
      if you were going to stay an LT motor with LT style heads keep it 350 or 355. i say this because i would figure you want the RPM capabilities as well versus what a stroker would give you. if you find the 366 or 396 discussion thread i asked Bret(sstrokerace) in there about a 396 LT motor. what he told me and what i have seen on many build ups is the fact that the LT heads cant hold a big valve. therefore limiting a large displacement engine. its not uncommon for a properly built 355 LT motor to perform better or so very close to a 383 or 396 stroker LT. so for the LT motors unless your going SBC1 heads i would say stay 350-355.

      as for the powerband on the LS motors. yes they peak very high on a lot of the high number cars. however there are plenty that have a lot of midrange and enough low end power to be great on the street. the best thing to do here honestly is go to LS1Tech.com and look in the dyno results section. people post their graphs and mods there. that way you can see what combos produced what results. i personally prefer a low and midrange power band or broad power band versus a high power band even if the high powerband is faster and makes more power. im not interested in numbers as much as i am driving pleasure.

      ive driven a 540 rwhp Z06 a lot. the car was procharged and had headers/cats. nothing else was done to the car to produce those numbers. the car had a 3.90 gear in it as well. honestly the car was brutal fast but it got old very quick for me. all the power was top end power. i built a normal C5 with full exhaust, the LS1 hotcam, and 3.90 gears. honestly i enjoy that car more. the midrange power was terrific on that car and it had plenty of low end as well. car only made 380 at the wheels. its all about enjoying the drive for me. make no doubt though if i was racing in any form where i had room to run id be all over the Z06 just because of its top end power. for the street though its a completely different. oh and Bill can atest to this i believe, but the magnacharger is hella fun on the street and im betting the KB will be too once its out. all the magnacharged vettes i built were fantastic for street driving. the H2 was too, but thats a different story
      Trey

      "The early bird may get the worm, but the second mouse gets the cheese."
      ~ Jon Hammond

      1979 WS6 Trans Am stock LT1/T56 drive train out of my Formula. BMW M-parallel rims. C5/C6 brakes

      build thread https://www.pro-touring.com/showthre...ghlight=begins

    13. #13
      Join Date
      Nov 2005
      Posts
      130
      Trey,

      Thanks for that. FWIW Lloyd and I just helped a guy get 438rwhp thru a 4L60E and a 8.5" rear in his Impala SS with a stock LT1 casting and a custom cam.

      You can do really well with the LT motor, the LS motor is easier to make power from but also more expensive.

      Bret
      Bauer Racing Engines
      Specializing in late model GM motors

      1964 GTO (work in progress for 13 years)
      600 HP 365 cube SBC
      C5 Front Suspension
      Satchel Link Rear
      T56
      Not gettin done anytime soon

      2000 Camaro SS SCCA FS Car
      Koni Adjustables
      35mm Front Bar
      DOT Race tires....

    14. #14
      Join Date
      Dec 2005
      Location
      Maryville, TN
      Posts
      839
      Yeah see... that's kind of what I was thinking. I don't mind to spend the money to do it right, but with the LS motors I almost feel like I'd be spending money for the sake of spending money and being able to say I've got an LS instead of an LT. After the holidays are over, I'll look you guys up and give you a call.
      A.K.A: That bald guy
      Find me on Facebook or my personal website.

      - 67 Camaro: Current Project Car

    15. #15
      Join Date
      Nov 2005
      Posts
      130
      Dan,

      The LT is a hell of a cheap platform to build from. You can make killer power and the only hold back is the dam intake manifold which I'm working on changing to make it easier to the average guy to run something better.

      Bret
      Bauer Racing Engines
      Specializing in late model GM motors

      1964 GTO (work in progress for 13 years)
      600 HP 365 cube SBC
      C5 Front Suspension
      Satchel Link Rear
      T56
      Not gettin done anytime soon

      2000 Camaro SS SCCA FS Car
      Koni Adjustables
      35mm Front Bar
      DOT Race tires....

    16. #16
      Join Date
      Aug 2005
      Location
      Asheville, NC
      Posts
      87
      LSx is the way to go. That is what i am putting in my 67 firebird. I have had an LT1 for about 8 years and is was a great motor, the lsx is just a step above. My 383 LT1, AFR 190's, hot cam kit, and shorties only makes about 380rwhp. I put this together in 98 and there were few cams available, but there are much better options now. 400-450 is not to hard with a better cam selection. Lsx market continues to get bigger and the prices are droping all the time. Prices will continue to fall as the gen IV block becomes the rage in the next few years.

    17. #17
      Join Date
      Nov 2005
      Posts
      130
      The intake is the real hold up on the LT1. I had a stock ported heads, solid roller 383 make 647hp with a Super Vic and a carb on it.

      Bret
      Bauer Racing Engines
      Specializing in late model GM motors

      1964 GTO (work in progress for 13 years)
      600 HP 365 cube SBC
      C5 Front Suspension
      Satchel Link Rear
      T56
      Not gettin done anytime soon

      2000 Camaro SS SCCA FS Car
      Koni Adjustables
      35mm Front Bar
      DOT Race tires....

    18. #18
      Join Date
      Dec 2005
      Location
      Maryville, TN
      Posts
      839
      The LT intakes suck? Interesting... I was under the impression that they were pretty good. I guess it makes since though... if they were so good, why would GM have made such a radical change with the design on the LS.

      Okay, so this leaves me with the same quandry. If you take away the LT intake, and we're doing aftermarket heads anyways... all you've got left is the block... which for all purposes is the same design as the destroked 400 package I've got sitting in my garage. Wouldn't I be better off just buying a new set of heads and finding an intake solution for the motor I've already got (with more cubic inches) instead of spending more money on another engine that I'm going to be replacing the same parts? What would I really be gaining? The computer and wiring (assuming that came with the LT / LS motor)?

      Has anyone had any luck / experience with the Edelbrock / Holley / Accel bolt on EFI kits?

      Thanks for the input guys!
      A.K.A: That bald guy
      Find me on Facebook or my personal website.

      - 67 Camaro: Current Project Car

    19. #19
      Join Date
      Nov 2005
      Posts
      130
      Dan,

      The 377 is probably a really good way to go if you top it off right.

      The stock LT1 heads with a stock intake can get you the power you want, but a going to aftermarket casting like a Dart Pro 1 (the new ones) and have someone like Lloyd port it with a cam would get you where you want to go easy.

      The LT intake was not what Ron Speary wanted to do on the LT engine design. He wanted a longer runner LS type intake but the head honchos didn't want to do that because they didn't like what they saw with the TPI intakes. One of those cases of "don't confuse me with the facts my mind is made up"

      Bret
      Bauer Racing Engines
      Specializing in late model GM motors

      1964 GTO (work in progress for 13 years)
      600 HP 365 cube SBC
      C5 Front Suspension
      Satchel Link Rear
      T56
      Not gettin done anytime soon

      2000 Camaro SS SCCA FS Car
      Koni Adjustables
      35mm Front Bar
      DOT Race tires....

    20. #20
      Join Date
      Aug 2004
      Location
      Dunwoody, GA
      Posts
      4,984
      Country Flag: United States
      Dan do this first before anything else. decide what you want out of the engine. what power level. what modification level. what it will be used for. you need to decide these things before you can really make an educated decision on which way to go. there are so many options out there. once you really decide what direction you want or need to go then you can start to decide what type of engine you need to build.
      Trey

      "The early bird may get the worm, but the second mouse gets the cheese."
      ~ Jon Hammond

      1979 WS6 Trans Am stock LT1/T56 drive train out of my Formula. BMW M-parallel rims. C5/C6 brakes

      build thread https://www.pro-touring.com/showthre...ghlight=begins

    Page 1 of 3 1 2 3 LastLast




    Advertise on Pro-Touring.com