Indeed sir! As long as we learn from our mistakes, that's what it's all about. I did manage to break the 8.2 rear end (supposed to be tougher than the 'other' 8.2's) by doing this, but had some spare parts from my other 8.2 to put it back into working order.
I had ticking lifter noise before rebuild and I have it still! How this can be possible? How often new lifter is faulty? New lifters are Delphi lifters from TA.
Is it ticking or clacking? Reason I ask, is a lot of people hear a clacking and assume its lifter/s Lifters tick. Rocker to valve contact if theres lash will clack. Remember setting Chevy rockers? Backing off till they just started clacking:grin:
Nice torque. HP numbers are decent . maybe Alittle more in it thru tuning. But still strong. Moderate compression. Thumbs up.
That was chassis dyno so I don't know how accurate those numbers are. My timing is 36 total and AFR is 12.5 at WOT.
i tried looking through the thread for the engine build specs but could not find them? Nice dyno numbers is sounds very healthy!
It was inertia dyno, I don't know brand. Wheel power was 263hp so engine power could be little more than 289. Tranny is chevy th350. Engine has 9.4:1 static, Crower 3, home ported heads, 800cfm Quadrajet, TA stage 1 intake, 1 5/8 headers, dual exhaust with x-pipe.
VERY respectable numbers from a mild engine. It's not outlandish to accept a 20% to 25% loss from gross power when measuring at the wheels. 263 RWHP would range from 328.75 hp @20% to 350.67 @ 25%. Do you know what the wheel torque was? If it was 370, that's big block torque. EDIT: if you took 289-263=26 as a reference and applied it to the 370 torque number, we'd see 370-26=344. This may or may not be accurate, but could give an indicator. The results are pretty spectacular and are probably VERY optimistic, but even if it was given a factor of 1.28:1 tq:hp ratio (370/289=1.28), the results may be a bit more accurate: 26*1.28=33.28, which would be the number subtracted from 370 to get 337 (rounded). Now take 337 divided by .8 (for 20% parasitic loss) and .75 (for 25% parasitic loss) to come up with 421.25 ft. lbs. @20% to 449.33 ft. lbs. @25%. Still optimistic I think, but hey truth is stranger than fiction. lol 329 hp and 421 ft. lbs. doesn't sound too outlandish for this combination.
Some confusion over this is not uncommon. Crower offsets their cams to 4* advance by default when installing the timing gears to the 'straight up' position, so even though it may look like 0*/0* on the timing gears, it's actually 4* advance...this is providing the cam has been accurately ground (many have not, and can be off by more than just a few degrees). If you set ICL to 107.5, the timing gears should appear to be close to 0*/0*, in which case Crower did a good job on their accuracy. This will give you the advertised 33*/66* @.050/.006 intake lobe locations. A static compression of 9.4:1 should put you in the safe range for a 66* intake closing point using fuel in your area (using European octane method). As reference, your peak power locations correspond to a 4* advanced location for this cam.
I believe 370tq is calculated engine torque, I don't know wheel torque. When I first intalled cam "straight up" I measured 112 ICL, cam card says it should be 108. When I advanced by 4 degree I measured 107.5 and leaved it there. Crower says peak power is 4500rpm and red line 5000rpm, I have peak at 4750. If cam would be 4 advanced peak power should be even lower than 4500rpm right?
Peak torque is determined by the intake port's MCSA and it's reaching a certain velocity, as related to the size of the cylinder it's feeding...except when the cam specs or induction severely choke it off. The cam may influence the shape of the torque curve. To determine actual shift points from a dyno curve requires loaded testing to be relevant, or on road (strip) testing. Inertia dyno's have a varied response, depending on brand and type. They can be useful for A to B testing, to show changes made. Better off driving it to find what the car likes.
The calculated torque probably refers to 'net' power and not 'gross' power, which means the engine will have more than 370 ft. lbs. without anything else added to it that removes power (parasitic loss). This is very good torque for a net figure, even if it isn't quite 421+ ft. lbs. gross--though who knows? A 4* advanced Crower level 3 with good compression, small tube headers and an "X" pipe is going to produce very impressive torque figures. Your home porting on the heads should improve it even further. ...which brings us to why it shows up as peak power numbers being a little higher than what Crower advertises. Your engine is breathing a bit better than a typical engine with this cam installed, which tends to raise the powerband some. The headers also help with this, and widen your powerband even more, which is why you see peak torque at 3200 instead of 3500 or so that you'd probably have seen with manifolds @4* advance. I have no doubts your power @2000 RPM is impressive as well, and a nice 2000 stall should be all this combination needs to maximize torque multiplication with street-friendly gearing. With 400+ ft. lbs., a 2000 converter should flash a bit higher than your typical small block and have some very good pull at that RPM. Also as a general rule, shifting an engine 300-500 RPM above peak horsepower usually puts your RPMs down into the meat of your torque band, but as was mentioned previously, you may want to drive it to get a feel for when it feels right to shift. I would usually shift my engines slightly after I could feel the hp just beginning to trail off, but this is a 'street' driving method, and track behavior may differ somewhat based on the rest of your car and what the timeslips say. Behavioral patterns and reaction times will vary from person to person, but if I were to stab at a wager, I'd say this engine prefers to be shifted (with a TH350 trans) somewhere around 5100-5300 RPM, and would pull strong to ~5500 as long as your valve springs were good and set correctly. Crower may have started to grind their cams straight up instead of putting them at 4* advance to avoid confusion maybe? Either way, it's always a good idea to degree the cam when installing it, so you know where you are. :TU: The cam description varies a bit, depending on if you're looking at the online catalog for it or reading it off the web page. I've ran this cam in a dyno simulator more times than I care to count, so I'm pretty familiar with it. There are others here on this forum who are very familiar with this cam too in real-world usage and testing. I'm sure the descriptions I gave will be reinforced elsewhere by others, if they care to chime in. This cam is very similar to the OEM replica GS cams in terms of powerband when installed at 4* advance, but with more power, which makes it an ideal upgrade path for a stock GS car with typical GS gearing. The combination you have now is one I would consider to be pretty much the perfect street setup for a Buick 350. Congratulations on all your hard work and excellent results!
I just ran another simulation using your engine specs and came up with 332.5 hp @4750 with 426 ft. lbs. @3000. Pretty close to the figures I guessed at earlier, with the torque RPMs wanting to hover around 3000-3250 at peak. I wouldn't use these numbers as your 'official' figure, they're just something to consider and give a general idea. This is also gross power, not net or wheel power, which will be considerably less. The torque figures are probably optimistic, and all power figures would fluctuate quite a bit depending on weather conditions, tune, and the dyno you used. Any way you slice it, it's nice power and would be major fun, last a long time, and get decent gas mileage.
Wow thanks Gary, good info! But cam is not advanced by 4*, it is where cam card want it to be. Cam card says: "If using lobe center method cam should be installed on an intake centerline of 108" and I have it on 107.5. Engine works nice but there is valve lifter noise somewhere in 1800-2000 rpm, Im not sure what to do for that. Or is it even lifter noise because it shows so narrow rpm area?
