SRT8dan

First of all, the L86 IS an LT1!!! Secondly, I used the Vette engine only to make a point, which your dyno graph also bears out. On your chart, torque peaks at 4100 rpm's and then starts to drop. But wait, the horsepower continues to climb, which is the point. The L86 is incapable of reaching the Vette redline of 6600. Ever wonder how Ferrari engines make so much horsepower and yet have relatively (note "relatively") low torque numbers? Because those engines, like the Ferrari 458 speciale 4.5 liter V-8 makes 510ft lbs of torque at 6250 and 600 hp at 9000 rpm's. I mentioned that horsepower is a mathematical derivative of torque x rpm's divided by 5252. Move the torque curve up in the rpm range and even more HP is created. Sure torque drops off at some point, but HP continues to climb until the torque drop off is so dramatic, the engine runs out of steam. It all revolves around engine design and what it is intended to do. Years ago when Chev brought out their big blocks, the high performance engines had little low end grunt because torque was created in the higher rpm range. They all were the same size engines, just different heads, intake, cams, etc. I guess I do not understand what your point is that torque drops of after 4000 rpms and HP at 5800 - 6000. How then does the LT1 Vette engine (2018) make 460HP? I believe its torque rating is the same at the L86...460.

Great video explaining where the denominator 5252 is derived. One example I always remember from the olden days was taking a Chev 350 small block and punching it out to a 383 ci. The additional stroke turned the engine into a torque monster (for the day) which is explained in the video’s first part regarding radius.

NOT CORRECT! As you can see in the J1349 Dyno chart for a LT1 Corvette engine, even though torque drops off, the horse power continues to increase. Use the numbers seen on the chart and put them into the equation mentioned in a previous post and see if the numbers work.

I agree. Chev already has a supercharged 6.2 engine. How hard would a detuned version be to put into a Silverado or GMC? They already have a stout enough rear end and a few tweaks on the tranny would not be all that difficult.

I did some additional research and found a great article on Holly's web site, and you are basically correct. Almost everything on the two engines are identical with the exception of the intake manifold ( equal runners on the Vette vs longer unequal ones on the L86), a better flowing exhaust on the Vette, and the dry sump on the Vette. Both engines have the same cam specs at .050 lift (200/207 degrees, .551/.522" lift -1.8 to1 rockers with 116.5 center line), both have sodium filled valves, and both flow 123 lbs/hr on the injectors). Since horse power is just a mathematical derivative of rpm x torque/5252, the added HP comes with the additional rpms the Vette engine is capable of. It is interesting to note that on the new LT2 Vette engine the cam specs increased +18 degrees on the intake and +4 on the exhaust to get to 495 HP.

After numerous searches I am still at zero. I am trying to find out what the difference is between my 6.2 L86 2018 Silverado engine and the same year Corvette engine that lists identical specs, but puts out considerably more power. Is just in the cam specs, or in the exhaust, or the throttle body? The LT2 Corvette now makes 496 HP and 470 ft lbs or torque. I know LT2 has revised intake runners (all the same length), a revised AF sensor, low restriction exhaust, dry sump lubrication, and a revised cam. It is still basically a LT1 engine that gained 75 HP and 10 ft lbs of torque, an 18% power gain. The LT1 Corvette engine had 40 more HP than My L86. What made the additional horse power. Can anyone shed some light? Thanks.

Thanks CamGTP. For that kind of money, I am beginning to believe the trans shifts just fine the way it is. I wasn't thrilled the way Diablo Sports sells the Predator Tuner. They never mention the additional $40 for the GM unlock feature nor do they say anything about the inability to do anything with the transmission.

I have a 2018 Silverado 1500 High Country with the 6.2 engine. Recently purchased a DiabloSports Predator 2 tuner, which to my dismay, does not have anything for the 8L90 transmission. Does anyone know why?