shadowsniper3006 Posted July 11, 2012 Report Share Posted July 11, 2012 if memory serves you said you used 1.8 ratio rockers which, like you said, is a fake cam change. Your using the ratio of the rocker to increase valve lift, I don't think the added ratio effects duration though. However for the valve spring pressures your using and the rpm your turning, a 3/8 push rod is hurting you more then its helping, just my opinion. Quote Link to comment Share on other sites More sharing options...
garrell.770 Posted July 12, 2012 Report Share Posted July 12, 2012 The 3/8" pushrods were recommended by the performance shop I use and they do nothing but LS engines, he said because of the sustained high rpms that it would be a good idea. The cost on the push rods was not that much so I don't think he was trying to just sell something. I was in his shop three weeks ago and counted 16 late model 2010 to 2012 SS Camaros and c6 Corvettes in addition to cars parked all around the outside of his building and almost all them were getting one turbo-charger and some twin chargers. HotRod magazine did the same change several years ago on a buildup series they did on an LQ9 engine, I had it under one of my favorites but I have deleted it so I don't know what year or month. I was about to start a new thread but I will go ahead and throw it out here to start. I need to add about another 30 to 40 horsepower like everyone as economical as I can. I ordered ceramic coated short tube headers yesterday and I already have Doug's Headers electric cutouts so with the headers installed and the cutouts open I figure I am picking up maybe 20 horsepower? What reccomenditions does anyone have for another 20 horsepower? Garrel Quote Link to comment Share on other sites More sharing options...
The_aSSet Posted July 12, 2012 Report Share Posted July 12, 2012 Shorty headers will not do anything for more power. Its been discussed here many times. And knowing the parameters you have to stay in would help when suggesting mods. Quote Link to comment Share on other sites More sharing options...
shadowsniper3006 Posted July 13, 2012 Report Share Posted July 13, 2012 (edited) The 3/8" pushrods were recommended by the performance shop I use and they do nothing but LS engines, he said because of the sustained high rpms that it would be a good idea. The cost on the push rods was not that much so I don't think he was trying to just sell something. I was in his shop three weeks ago and counted 16 late model 2010 to 2012 SS Camaros and c6 Corvettes in addition to cars parked all around the outside of his building and almost all them were getting one turbo-charger and some twin chargers. HotRod magazine did the same change several years ago on a buildup series they did on an LQ9 engine, I had it under one of my favorites but I have deleted it so I don't know what year or month. I was about to start a new thread but I will go ahead and throw it out here to start. I need to add about another 30 to 40 horsepower like everyone as economical as I can. I ordered ceramic coated short tube headers yesterday and I already have Doug's Headers electric cutouts so with the headers installed and the cutouts open I figure I am picking up maybe 20 horsepower? What reccomenditions does anyone have for another 20 horsepower? Garrel i disagree with your shop. Having a ton of cars outside doesn't impress me, what they say is what i judge on. There are some shops out there that have built 1000 hp motors but swear if you take a bottom end LS motor over 6500 rpm it will self destruct. I'm running a 5/16 push rod at 7350 on the dyno with much higher valve spring pressure and don't see a problem, or at least what i would look for as a problem. Any way, what can you get away with in your class? I would start by canceling your header order and get a pair of long tubes as said above. On a budget and for your HP level i would usually say go with a 1.750/2,5 OBX header but since you are living at a sustained rpm i would think about a 1.875/3 header. It costs MUCH more, but may just be up your alley for what you are doing vs the short lived rpm of drag racing. light weight wheels would help you. My rims/tires weigh in a 42 pounds a piece and the stocks weight in around 82. Granted I'm running a smaller tire so it weighs less but the rims alone will save you at least 30-35 pounds per rim. I use center line forged rims because of their price. As far as tire diameter...i have no idea on a top speed truck. I would think a cam would help you VS the 1.8 rockers. And if you switch you will either have to run stock ratio rockers, roller tip or stock, or have a cam spec'd based on a 1.8 rocker. I could only guess at what your cam would be, i would think a cam with a wide lsa and a 220ish duration, but really you need a professional like zippy to spec out a cam for a top speed truck. It would be very interesting and educational to see what a cam would be for a top speed truck. Is your tune locking the converter? If not, or maybe even if it is, i would say a 10.5" converter with a triple disk clutch so you can try locking the converter at different speeds and have a good shot you won't take the lock up clutch out. an intake that can run a 90mm tb, like the TBSS would help it breath. A ram air tube for your intake would also help the IAT's stay down. Lower thermo stat, less antifreeze and more water and maybe a additive mixed strongly into the coolant to keep temp down. under drive pulley didn't help me to much in the quarter but may help at sustained rpm lowering the truck with a chin spoiler may also help glass or carbon hood in stock form with no ram air or fake air intakes your in a new world on this site, I'm not used to top speed, just getting to the end in the least amount of time Edited July 13, 2012 by shadowsniper3006 (see edit history) Quote Link to comment Share on other sites More sharing options...
garrell.770 Posted July 13, 2012 Report Share Posted July 13, 2012 No cam changes and not suppose to run headers but I found out that cars in production classes were running short tube headers and I talked with some of the owners and some of them have big budgets and go to wind tunnels during the off season and a few have crew chiefs that do their on tuning and they though the short tubes in conjunction with the cutouts would have basically the effect of running upen headers and they though 25 to 30 hp so I was being conservative when I was looking for 20 hp. The headers along with long tube headers for my Corvette shipped today! You don't think that there will be any hp benefit with the combination I am planning? I am old school where we would take a 300 or maybe a 350 hp 350 ci. or even a 327 ci. install a tunnel ram or just an aluminum highrise, call one of the cam companies and tell them what we were planning ie. still trying to run on the street, 1/8th or 1/4 mile and they would suggest a cam profile, install hedman headers and off we would go with our m22 rock crusher and we managed to run pretty fast for the day,ie. low 13's or maybe into the 12's. I drove a 69 Plymouth Sattelite for a Dodge/Plymouth dealer in the early 70's and I think we ran 11.30s in the early 70's. Some of the changes between Maxton last Oct. and Ohio in April definitely worked because I could immediately tell in my seat of the pants dyno and my truck picked up because of a 7 mph improvement in a stronger wind. That was with the rocker/spring change, porting the throttle body, and the tuneup. One change appears to give you a fair amont of hp versus the cost is the FAST intake which claims 30+ hp for around $1150.00 installed, what is your opinion on this change. This will probably be my last trip as a matter of fact I never planned on going back but after this Months issue of HotRod cane out and documented my making the first pass at the inagural Ohio Mile and mentioning ny coming back from an illness and getting out of what was suppossed to be a lifetime in a wheelchair people from other forums and clubs are emailing and sending me private messages as well as local parts shops and hotrod clubs are encourageing me to go back one more time and try to break and reset two of my records and set two more that are open so deep that no one will break them for a long time. I doubt they would catch lowering the truck but it is not allowed. I can run a chin spoiler but I looked for one two months and could not find one that would work, the deeper the better. The modifications I described above chassis dynoed at 62 hp and added 7 mph, I just want to pkckup that 300 to 400 rpms that I left on the table. Oh, one more thing the reason I was the first vehicle in line and was mentioned in HotRod Mag. wasn't because of my recovering from a heart attack followed by three strokes. Iam a chronic insomniac and never go to bed so I got my crew up and we picked up drive through breakfast and were sitting at the gate into the pitt and to the left one mile the staging lanes at 4:45 am and the gate didn't open until 6:00 am and the very efficient starting line crew had no idea who was in the big black truck with the dark tinted windows. They had to shut off registrations at 175 abd with threatening weather I was going to get one good run in. Garrell Patterson Quote Link to comment Share on other sites More sharing options...
garrell.770 Posted July 13, 2012 Report Share Posted July 13, 2012 I did some research during the night and I did find the web site I mentioned above where HotRod did a buildup on an LQ9 engine and along with the rollertip rocker change they reccomend the heavy wall 3/8" pushrods because these engines were known for crushing pushrods at high rpms, the website is www.hotrod.com/techarticles/engine/hrdp_o710_6l_ls_series I also went to numerous sources about headers and the general concensious is that short tube headers on an LQ9 frees up 10 to 15 hp, but you lose it at the collectors with a stock or even high performance exhaust system but if you can run them open it will free up, not make, maybe 15 hp. That was my question about using them in conjunction with the pair of 2 3/4" cutouts.Does anyone think this might be true? The HotRod article says around 11 hp with the FAST intake which is less than the mfgrs. estimate of 25 to 30 hp. The cost for 20" lightweight wheels and narrow speed rated tires would be cost prohibitive and would not be something I would want to run around home. A deep chin spoiler would help stop as much air from getting under the truck so if anyone has a source of one designed to fit up behind the bumper and hang down low enough I would appreciate info, thanks. Garrell Quote Link to comment Share on other sites More sharing options...
LSR Mike Posted July 13, 2012 Report Share Posted July 13, 2012 (edited) Garrell, you can't run a chin spoiler in Production Class, has to come on the vehicle or be available as a OEM from the dealer, over 500 made, Key word "Production". You CAN do anything you want to the motor, short of a turbo or supercharger. watch out for suggestions here, they're mostly Sat. Nite Drags, No offense guys, but the classes and rules of LSR are a world of thier own. Edited July 13, 2012 by LSR Mike (see edit history) Quote Link to comment Share on other sites More sharing options...
shadowsniper3006 Posted July 13, 2012 Report Share Posted July 13, 2012 Garrell, you can't run a chin spoiler in Production Class, has to come on the vehicle or be available as a OEM from the dealer, over 500 made, Key word "Production". You CAN do anything you want to the motor, short of a turbo or supercharger. watch out for suggestions here, they're mostly Sat. Nite Drags, No offense guys, but the classes and rules of LSR are a world of thier own. I guess i'll keep my Sat. night drag suggestions to myself from now on, no offense..... Quote Link to comment Share on other sites More sharing options...
garrell.770 Posted July 13, 2012 Report Share Posted July 13, 2012 I have actualy seen Silverado trucks fron the years of the SSS that had chin spoilers, I had googled for months trying to find a GM spoiler that would fit behind the SS bumper, I don't want to go internal with anything ie. cam change etc. but I could feel the rocker arm/valve spring change along with the ported throttle body change in my seat of the pants dyno before I saw the numbers. Everything I have done since my first 123.5 mph pass at Maxton last Summer has worked so far. My record seting pass at Maxton was at 126.999 and we had a bad wind that weekend and my best run at Wilmington in April and again the wind was against us that weekend also was at 133.869. I have said before I really think I would have ran 135 to 137 mph if the wind wasn't a factor. When I go back I want to have a speed improvement goal as I have each time but I have got to be carefull because I would be getting close to having a talk with Keith Turk and Keith has been a lot of help to me so I want to stay on his good side. Garrell Quote Link to comment Share on other sites More sharing options...
2bfast Posted July 14, 2012 Report Share Posted July 14, 2012 Wow, all that talk for 50 horsepower? Seems u need to step away from that shop you talk of and think about this. You drive a heavy boat for a truck. So tell me what rocker arms are really gonna do for you? Not much. Its not horsepower you are after...its torque. You have to find.a way to get that weight moving. Try again Quote Link to comment Share on other sites More sharing options...
2bfast Posted July 14, 2012 Report Share Posted July 14, 2012 (edited) watch out for suggestions here, they're mostly Sat. Nite Drags, No offense guys, but the classes and rules of LSR are a world of thier own. Then post on an LSR forum. Brads suggestions are a little more than a " Sat. Nite Drags" suggestion. Dont test that ol boys technical knowledge cause he'll walk circles around you. To the OP, think about it. U have a heavy truck, think of way to make it move first....and thats not horespower. Making a novel on rocker arms wont get u there. Edited July 14, 2012 by 2BFAST (see edit history) Quote Link to comment Share on other sites More sharing options...
2bfast Posted July 14, 2012 Report Share Posted July 14, 2012 (edited) edit Edited July 14, 2012 by 2BFAST (see edit history) Quote Link to comment Share on other sites More sharing options...
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