dmanzo57 Posted March 24, 2003 Share Posted March 24, 2003 Bore: 4.040 Stroke: 3.48 Rod: 6.0 Piston: Manley Pro Series hollow dome(13:1 w/64cc head) Heads: Brodix Track 1, 215cc intake, 67cc chamber(resurfaced twice, so less than 67cc) Cam: Lunati solid roller, .640/.645 lift, 308/316 duration(276/284@.050), 106 LS, installed 4 deg advanced. Intake: Edelbrock Super Victor Carb: Holley HP4150 950CFM Exhaust: Hedman 1 3/4" primaries, Flowmaster collectors, no mufflers. Timing: fixed, initial=total=38 degrees BTDC Fuel: 114 octane, Union 76 race gas Trans: powerglide, 1.82 low, 8" converter, 5000 RPM stall Rear: Ford 9", 5.14 gears, 30" tall slicks Weight: 3125 lbs w/driver Best ET: 10.71 Best MPH: 125 Best 60': 1.46 The problem I'm having is the engine feels like it runs out of steam by 7000 RPM. I cross the finish line at about 7400 to 7500 RPM. The best ET is attained by shifting at 6500 to 6600 RPM. Any more than that and the car slows down. Shouldn't this combo pull strong to 7500 RPM? What am I missing? Thanks, Don Quote Link to comment Share on other sites More sharing options...
Mike C Posted March 24, 2003 Share Posted March 24, 2003 If the cam is ground advanced, as many are, it may be overadvanced. This would shift the peak power lower. If the Track 1's are stock, you may be having cylinder head flow induced "rev limits". I would start with the Proform degree wheel and check cam timing, although that may well have been done. Calculations show about 486 rwhp, which should be 550 or so at the flywheel which is about all the stock Track 1's are worth. Look at the bright side, the motor will last a lot longer shifting below 7k Quote Link to comment Share on other sites More sharing options...
Mudge Posted March 24, 2003 Share Posted March 24, 2003 Woah, that is HUGE. I have seen a 3650 pound 6 speed car with a 245/248 solid roller pull a 10.8@130 (slicks). That is with a 7k limit and shifting probably near the limit, so yes with a cam that huge you should have more RPM to work with, it also had smaller heads. How confident are you in your ignition setup? Quote Link to comment Share on other sites More sharing options...
dmanzo57 Posted March 24, 2003 Author Share Posted March 24, 2003 The Track 1 heads are stock, except for the resurfacing. The cam card says to install with intake center line at 102 to make the cam 4 degrees advanced. The ignition system is sound. MSD7AL, billet dist, Blaster 3 coil. So, maybe I've reached the limits of the stock Track 1's? That's kind of discouraging, expensive to remedy. Thanks for the replies. Don Quote Link to comment Share on other sites More sharing options...
Mudge Posted March 24, 2003 Share Posted March 24, 2003 I thought that all of the Brodix products were basically castings ready for porting, as if to say not really a finished product. AFRs are almost the same way, they flow OK stock but for thier port size are not all that hot. LT1 402 with 195 AFRs home ported, 245/248 pulled about 480 RWHP. Its EFI but still SBC enough that I figure the comparison is ok, other than the added cubes of the 402 over your 385. If anything he may have a better torque band from the FI and stroke, but HP and shift points I would think to be relatively equal if you had the same cams. Your cam is so huge though it makes me think NASCAR and 8500-9500 RPM running. With that much lift on the cam too, are you sure your not hitting port stall? With most heads anything above .550 is going to be dead, although with your bigguns 215s I dont know. Quote Link to comment Share on other sites More sharing options...
dmanzo57 Posted March 24, 2003 Author Share Posted March 24, 2003 The Track 1's are supposed to be bolt-ons. They come with CNC matched ports, blended bowls, etc. Here's what Lunati says about the cam... ROLLER, Super Gas/Super Comp with 350-406 engine. Broad power band. Ultimate bracket cam. 4400-7800 ...Seems to me it should be still going strong, even past the finish line. Don Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted March 24, 2003 Share Posted March 24, 2003 IF YOUR POSITIVE your not getting into minimal valve float (which sounds likely) and yout fuel pressure is stead at about 6lbs or better during the whole 1/4 mile pass heres what Id try add a 1" -2" thick 4 hole carb spacer retard the cam 6 degrees retard the ignition timing about 1-2 degrees in top gear add a tappered merge collector with about 15"-20" long extension http://www.burnsstainless.com/MergeCollectors/mergecollectors.html drop back to a 4.88 rear gear Quote Link to comment Share on other sites More sharing options...
dmanzo57 Posted March 26, 2003 Author Share Posted March 26, 2003 Thanks for the advice, Grumpy. The springs are fresh, K-motion 1.55" doubles w/damper, 200 lbs seat pressure. Fuel pressure is set at 7.5 PSI and is steady for the whole 1/4. Going with the powerglide, with the 1.82 low gear, has made things difficult. I need the low rear gears at the starting line, but then run out of RPM before the finish. Do you think it's possible to make the same horsepower that I have now, but at a lower RPM range, with just a cam change? Then maybe with 4.88 rear gears I could pick up some MPH and not lose much in the first 60'? Thanks again, Don Quote Link to comment Share on other sites More sharing options...
biohzrd Posted March 28, 2003 Share Posted March 28, 2003 have to agree with grumpy on this one. check the valve springs. have a similar setup in a friends car and had the same problem. it would fall flat on its face after about 6500 even on the spray. put in new springs and that did the trick. now she'll scream all the way to 7500 no problems. Quote Link to comment Share on other sites More sharing options...
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