300WHP Supernatural 3.XX Coming Soon! (Page 16/54) La fiera APR 05, 09:37 PM La fiera APR 19, 01:14 PM Since I'm upgrading the valvetrain to make it more efficient I had to re-work the cam profile I previously had to take advantage of the valvetrain upgrade. Also taken into consideration was the "Race Pipes" that I have on the 3.4 now and the percentage of exhaust to intake flow ratio. I dubbed it the "370 GTO" cam WIth a primary coat of dry Molibdenum its going in with plenty of Gibbs Racing breaking lube! Timing chain on and camshaft degreed. thedrue APR 19, 02:59 PM You are doing some great work and it is exciting to see someone else pushing the 60degree engine platform. I look forward to your results. That being said I do wonder why you are using the Camaro engine and not any of the highly available roller cam blocks? I have moved away from flat tappet completely and see no reason to even be messing with it in this day and age. Not to mention that any of the later blocks have a much easier to seal cast aluminum structural oil pan with better bottom end support and a windage tray. They also have an OEM oil cooler option that is really trick. I just view it as a much better starting point in my opinion and is just as easy to mount and work with as the Camaro engine. Keep up the good work and I cant wait to see how this engine performs... I may have to copy some of your bottom end ideas for my next race engine! La fiera APR 19, 11:43 PM quote Originally posted by thedrue: You are doing some great work and it is exciting to see someone else pushing the 60degree engine platform. I look forward to your results. That being said I do wonder why you are using the Camaro engine and not any of the highly available roller cam blocks? I have moved away from flat tappet completely and see no reason to even be messing with it in this day and age. Not to mention that any of the later blocks have a much easier to seal cast aluminum structural oil pan with better bottom end support and a windage tray. They also have an OEM oil cooler option that is really trick. I just view it as a much better starting point in my opinion and is just as easy to mount and work with as the Camaro engine. Keep up the good work and I cant wait to see how this engine performs... I may have to copy some of your bottom end ideas for my next race engine! Well thank you very much for your kind words and complements! But to answer your question on why I don't use the highly available roller cam block, the one thing that keeps me away from them is the weight of the lifters. A good solid flat tappet lifter weights 60 grams and the roller lifter in your V6 weights about 325 grams. That is almost five and a have times the weight of one solid lifter! Now multiply that weight times 12. On roller lifters only, your engine is carrying 8.60lbs of extra weight That means that if you are running a very aggressive cam you must have a very hi pressure set of springs to prevent valve float and keep those lifters under control. If you are a visual person like me here are 2 pictures that represent the weight difference between a roller and a solid flat tappet lifter. That's 3 exhaust valves and 1 push rod from the stock 3.4/2.8 engine and 1 pen.= 1 roller lifter Thats 2 intake valves out my 206cc Go-Kart engine.= 1 solid flat tappet lifter. Also your RPM climb will slow down due to the weight of the lifters and the engine will loose between 1300 to 800rpm also due to the extra weight. And then last but not the least, the timing chain will stretch easier and faster due to the lifters weight. So, the bottom line is that the few hp you think the roller cam gives you due to friction, It will require 5 times that same hp to run it because of the weight of its components. On a low RPM, slow response UPS or FEDEX truck rollers lifters work wonders! But on a All-Out racing engine I'll never use them. Now, if everything is lighter, the engine will rev faster, more freely and higher. Will need less spring pressures and less timing chain stretch. My goal is not only 300WHP, but also how fast it gets there. fieroguru APR 20, 09:51 AM Rei, The real benefit of the roller lifters isn't the reduced rotating resistance, it is the roller tip allowing lobe ramp rates far beyond what a flat tappet allows (flat tappet lobe ramp rates are limited so the edge of the tappet doesn't gouge the cam lobe). The faster ramp rate gets you to the higher lift portions of the profile faster and you stay there longer with the same overall duration which provides a significant area under the curve benefit to them. Solid roller lifters are lighter than hydraulic rollers (but still heavier than flat tappet) and might be a good compromise, but I also don't know if there are any aggressive roller cam options for the 60 degree V6 family either. It might be worth getting a roller lifter and cam and dial indicate the ramp rate profile between the two. lou_dias APR 20, 11:39 AM WOT-Tech sells a variety of roller cams...up to .540" lift IIRC. I just switched to E85 and I'm still tuning but I picked up 7rwhp and 8 or 9 ft*lbs... If you don't care about fuel economy and just want even more power, I recommend it. thedrue APR 20, 11:43 AM Thanks for the response! I knew you must have had a very good reason for doing what you do, engines like this don’t happen by accident. I think you might want to rethink your roller lifter weight though. LS lifters, the same diameter but taller than 60° lifters, appear to weigh 122 grams. I would expect a 60° roller lifter to weigh less than double a flat tappet. Combine that with the shorter pushrod weighing less and the weight penalty may not be as great as you think. Also I believe the roller lifter is inherently more reliable and can take higher spring loads better. Although flat tappets have been very successful they just take much more care to not screw up the cam. I have a set of roller lifters on my bench but no scale to verify. There are also no solid rollers or other performance hydraulics available for this platform. I just went through all that. I thought the v8 lifters would work but they’re too tall. Anyway, I’ll keep following along and rooting for you, good luck! La fiera APR 20, 11:01 PM quote Originally posted by lou_dias: WOT-Tech sells a variety of roller cams...up to .540" lift IIRC. . The cam on this engine is .550 on the intake. Will APR 21, 10:36 AM quote Originally posted by fieroguru: Rei, The real benefit of the roller lifters isn't the reduced rotating resistance, it is the roller tip allowing lobe ramp rates far beyond what a flat tappet allows (flat tappet lobe ramp rates are limited so the edge of the tappet doesn't gouge the cam lobe). The faster ramp rate gets you to the higher lift portions of the profile faster and you stay there longer with the same overall duration which provides a significant area under the curve benefit to them. Solid roller lifters are lighter than hydraulic rollers (but still heavier than flat tappet) and might be a good compromise, but I also don't know if there are any aggressive roller cam options for the 60 degree V6 family either. It might be worth getting a roller lifter and cam and dial indicate the ramp rate profile between the two. This. quote Originally posted by La fiera: The cam on this engine is .550 on the intake. At the same peak lift, the greater area under the lift curve means that a roller cam can get way more air into the cylinder than a flat tappet cam. quote Originally posted by thedrue: I think you might want to rethink your roller lifter weight though. LS lifters, the same diameter but taller than 60° lifters, appear to weigh 122 grams. I would expect a 60° roller lifter to weigh less than double a flat tappet. Combine that with the shorter pushrod weighing less and the weight penalty may not be as great as you think. Also I believe the roller lifter is inherently more reliable and can take higher spring loads better. Although flat tappets have been very successful they just take much more care to not screw up the cam. I have a set of roller lifters on my bench but no scale to verify. There are also no solid rollers or other performance hydraulics available for this platform. I just went through all that. I thought the v8 lifters would work but they’re too tall. Would a *MECHANICAL* LS roller lifter work? There are a LOT of those on the market, including ones with the roller riding on pressurized oil instead of needle bearings, making them immune to bearing failure with stiff springs and high ramp rates. Will APR 21, 10:42 AM quote Originally posted by La fiera: the roller lifter in your V6 weights about 325 grams. I don't have one to weigh, but this is definitely not an accurate weight. That's 10 oz.