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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Not intending to restart the whole 350 vs 305 debate, just ran across an interesting 2001 post on another Camaro forum. For those die hard 305 owners who insist on working over their 305, this is probably a good simple guide to horsepower. There are some good comments in the thread too.
Vortec heads aren't the value they once were. If you are getting a set at a good price, they're probably attached to the engine that should replace your 305.
It's an interesting read. I think some of the forum members there make good points. The carb and intake certainly seem like overkill, at least until the heads and cam are in place to take advantage of it. Interesting that in the move from a dual plane to a single plane, the horsepower and torque not only did not change, but it did not move in rpm at all. Charts showing mid-range torque between the two would be interesting.
I'm not quite sure how you go from an '82 LG4 that's 145 horse power new, add 80k miles, headers, dual pipes and HEI, and make 197 horsepower. That's 52 h.p. That doesn't make sense.
I'd sure like to see the torque curve on these different phases of the build, Vs. just peak numbers. I'd also like to see them continue to use the dual plane Performer, and see where that torque peak move to Vs the single plane. An RPM would also be interesting to see.
I also don't understand the torque peak moving up 900rpm going from WP S/R heads to Vortec heads. That is not the VORTEC heads reputation.
A 305 with a torque peak at 4800rpm is not going to be much fun out of the hole. And the gear and converter that would make that fun to drive would be hard to live with on the street I would think.
Seems like a combo built to make max horsepower with no regard to street-ability, but with an eye towards grabbing a banner at the top of the magazine cover. It's what used to sell magazines. As much as I miss many of the old mags, series like Engine Masters can be a lot more useful / educational, IMO.
I'm not quite sure how you go from an '82 LG4 that's 145 horse power new, add 80k miles, headers, dual pipes and HEI, and make 197 horsepower. That's 52 h.p. That doesn't make sense.
Dyno numbers vs. RWHP with accessories on and running. They removed the engine from the Camaro and put it straight on the dyno with headers, 3" dual pipes to Flowmaster mufflers, and a HEI distributor with 22 deg total advance. This gave a baseline dyno result of: 197 HP @ 4,000 rpm. 261 ft/lb torque @ 3,100 rpm.
Originally Posted by DynoDave43
Seems like a combo built to make max horsepower with no regard to street-ability, but with an eye towards grabbing a banner at the top of the magazine cover. It's what used to sell magazines. As much as I miss many of the old mags, series like Engine Masters can be a lot more useful / educational, IMO.
It's an interesting read. I think some of the forum members there make good points. The carb and intake certainly seem like overkill, at least until the heads and cam are in place to take advantage of it. Interesting that in the move from a dual plane to a single plane, the horsepower and torque not only did not change, but it did not move in rpm at all. Charts showing mid-range torque between the two would be interesting.
I'm not quite sure how you go from an '82 LG4 that's 145 horse power new, add 80k miles, headers, dual pipes and HEI, and make 197 horsepower. That's 52 h.p. That doesn't make sense.
I'd sure like to see the torque curve on these different phases of the build, Vs. just peak numbers. I'd also like to see them continue to use the dual plane Performer, and see where that torque peak move to Vs the single plane. An RPM would also be interesting to see.
I also don't understand the torque peak moving up 900rpm going from WP S/R heads to Vortec heads. That is not the VORTEC heads reputation.
A 305 with a torque peak at 4800rpm is not going to be much fun out of the hole. And the gear and converter that would make that fun to drive would be hard to live with on the street I would think.
Seems like a combo built to make max horsepower with no regard to street-ability, but with an eye towards grabbing a banner at the top of the magazine cover. It's what used to sell magazines. As much as I miss many of the old mags, series like Engine Masters can be a lot more useful / educational, IMO.
I have the graphs somewhere of the full dyno pulls from that build. It was definately not an all out performancr build. The cam they used had less duration than the L30 I had in my Tahoe and the old LE9 I had in my G20 van. Tri-Y headers into the factory dual exhaust with an X-pipe added and a performer rpm manifold put my old 83 G20 to 181 rwhp and 268 rwtq. It was factory net rated at 165 hp. With ported 601s and a 218/218 @ 0.050, 106 LSA cam installed on a 102 ICL that old LE9 cranked out nearly 250 hp at the tires and 290 tq.
Vortec heads raised the torque peak on every engine I used them on. Put better heads than Vortecs and the peak increases even more. GM used a smaller cam in the vortec 350 than the TBI 350. Torque peak at a higher rpm happens when the engine breaths better with the same cam timing. The Vortecs lost a little torque in this build because of the loss of compression. 305 Vortecs would have made more HP than the 350 Vortecs on that 305.
Fast-
“With ported 601s and a 218/218 @ 0.050, 106 LSA cam installed on a 102 ICL that old LE9 cranked out nearly 250 hp at the tires and 290 tq.”
Was that cam the old Crane FT 274H06?
If you wanted to duplicate that cam’s specs in a hydraulic roller for use in a converted carbureted L03, what custom single pattern hyd roller 106 LSA cam manufacturer would you go with?
Fast-
“With ported 601s and a 218/218 @ 0.050, 106 LSA cam installed on a 102 ICL that old LE9 cranked out nearly 250 hp at the tires and 290 tq.”
Was that cam the old Crane FT 274H06?
If you wanted to duplicate that cam’s specs in a hydraulic roller for use in a converted carbureted L03, what custom single pattern hyd roller 106 LSA cam manufacturer would you go with?
IIRC Melling cam but was the same grind. I think even Summit has the same grind. I would probably avoid Comp atleast their XE or XFI lobes. The cam in my 383 was ground on Magnum High Lift lobes. Howards, Crower and Isky make great cams.
I also ran an old Federal Mogul CS1014R in the 305. Had a smoother idle and more vacuum but the hotter single pattern 218/218 106 lsa cam out performed the dual pattern 204/214 on a 112 everywhere.
This was a 0-90 mph run in the worst case scenario with the cammed L30 in my Tahoe. It was on 32" tall P305/50R20s and pointed uphill on an on-ramp. Truck still had the stock torque converter and 3.42 gears. Someone had swapped the factpry 3.73 rear for a 3.42 rear and I did not know until later, speedo is off 9 mph @ 80. 81 mph = 90 mph. Also still had the stock exhaust manifolds, stock 1-7/8" pipes to the muffler, stock cats and a stock muffler at the time. Middle of summer with a mechanical fan on it and the a/c was on. Also had the stock airbox and a paper filter. It was early in the tuning process and still running a stock L30 tune. With a S10 converter, long tubes, dual 2.5-single 3" exhaust using a merge Y, volant intake, e-fans, and a good tune shifting near 6,200 rpm it really woke up. Even with the cards stacked against it, the 305 still moved the ~5,500 lbs of the Tahoe well. This was also a ~300K mile L30 that I re-ringed and put bearings into.
09-04-2021, 06:39 PM
