t-rex_camaro

ok i have a 91 rs 305 with a cam with .465 lift and 1.6 rrs. no ac no smog pump shorty headers. and 2 1/2 all the way to the rear wheals with glasspacks. oh and motor mounts and trans mount. but all i get is top end power. i need some lower end power. any tips and parts that would help regane my low end.

BMmonteSS

Need to know a little more about the cam, most importantly the duration @ .050 lift, and the lobe seperation. My guess is you have way too big of a cam for a close to stock LO3. Not much you can do other than swap to a smaller cam if indeed that is your problem.

Also what kind of tuning have you done? If you haven't done any you left a whole lot of power on the table, and that could deffinately help get back some of your low end.

TierAngst

Supposing it has a good tune, gears and torque converter will help a ton on low end.

t-rex_camaro

Cam Style:Hydraulic flat tappetBasic Operating RPM Range:2,200-5,200 RPMIntake Duration at 050 inch Lift:224Exhaust Duration at 050 inch Lift:224Duration at 050 inch Lift:224 int./224 exh.Advertised Intake Duration:282Advertised Exhaust Duration:282Advertised Duration:282 int./282 exh.Intake Valve Lift with Factory Rocker Arm Ratio:0.465 in.Exhaust Valve Lift with Factory Rocker Arm Ratio:0.465 in.Valve Lift with Factory Rocker Arm Ratio:0.465 int./0.465 exh. liftLobe Separation (degrees):114Intake Valve Lash:0.000 in.Exhaust Valve Lash:0.000 in. thats the info on the cam its a sumit cam. also i dont have any computer tuning. i dont whant to do it myself becas i would mess up alot. im not with computer stuff gust a hands on guy. i know of a realy good dyno shop. should i take my car there and have them tune it. do u think they could tune it right. my bro whent to them and he sead there realy good.

BMmonteSS

Without a tune, I say your damn lucky to make it out of the driveway. You're probably making about 50 hp less than stock too. My 350 with a 218 cam wouldn't spin the tires off the line with a stock converter. It would light them up about 20 feet out of the hole though. You can add about 500-1000 rpm to that power band that summit says since it was based on a 350. You'll need at least a 2400 stall, maybe even a 2800 to get it moving. No way to expect a bunch of bottom end with that cam.


You really need to get it tuned, or take that cam back out. You'll pay an arm and a leg to get it tuned, assuming that the shop has any experience with TBI. Then if you ever change anything you'll need to retune it.

Gunny Highway

iTrader: (1)

As mentioned, the duration is too much for the 305. Hell, I purposely designed my 350 for low end grunt and I have a 204/214 of duration and I'm putting down 365 RWTQ that peaks at 2300 RPMs. Bigger is not always better with cams, especially ones that are in computer controlled cars.

t-rex_camaro

thats crazy. becas i drive it almost every day and i can do realy good burnouts. ill take a pic of my back tires and the bridge i do them on to prove it. wow thats weard. becas it moves gust fine its gust theres not much low end. but i put those 1.6s on gust two days ago and it has some lowend it spins the tire off the line at about 1500 to 2000rpm. hummm well do u guys know of anyone in the central wisconsin area that realy knows there stuff abou computer buring. thanks for any info

Fast355

iTrader: (2)

That is not much different than the L82 cam that I had in my 312 in my Van. It liked 3.73 gears and a 2,800 stall to make it a good performer. I had heavily ported 081s, a Holley intake, 454 TBI unit, headers, and dual 3" exhaust to make it run. The bulk of its powerband was from 1,500-6,500 rpm with a strong charge from 2,500-5,800. Cruising along in OD with the converter clutch locked, it was a dog, a stab of the throttle would wake it up nicely though. It was so doggy in OD that I had to find a cruise control servo for a 4.3 TBI van to keep the cruise from slowing down 5-10 mph on hills(the orifices inside are different sizes for different engines/ vehicles/etc). With the 4.3 cruise servo it did well, until you hit enough of a hill to make it go near WOT, it would hit 2nd at 65-70 and sling shot you down the road. The low-end stunk in OD, but it really woke up the 2,800-3,200 RPM range in 3rd gear while towing 4,000+ lbs. Had no difficulty pulling 65-70 mph down the highway in 3rd, plenty of power there. I actually used less throttle with the 224/224 cam towing than I did with the 204/214 cam.

FWIW, I upgraded from a 204/214 @ .050 cam to this one, it would not even start on the chip from that cam.

t-rex_camaro

thats cool ill have to get some gears and a 2,800 or so stall soon. people keep teling me thats way to big of a cam in a 305 with 1.6s but it feals gust fine. it runs like a champ it gust lacks on the lowend

BMmonteSS

It doesn't run fine, you just don't know what it's capable of. You have a whole lot of power left on the table. I'm starting to think that you didn't get the cam you thought you did. The car should have some serious drivability issues with that cam. My car wouldn't even start with a 218* cam in a 350. Your cam is a full 2 or 3 steps above this.

t-rex_camaro

Product Line:Summit Cam and Lifter KitsCam Style:Hydraulic flat tappetBasic Operating RPM Range:2,200-5,200 RPMIntake Duration at 050 inch Lift:224Exhaust Duration at 050 inch Lift:224Duration at 050 inch Lift:224 int./224 exh.Advertised Intake Duration:282Advertised Exhaust Duration:282Advertised Duration:282 int./282 exh.Intake Valve Lift with Factory Rocker Arm Ratio:0.465 in.Exhaust Valve Lift with Factory Rocker Arm Ratio:0.465 in.Valve Lift with Factory Rocker Arm Ratio:0.465 int./0.465 exh. liftLobe Separation (degrees):114Intake Valve Lash:0.000 in.Exhaust Valve Lash:0.000 in.Computer Controlled Compatible:NoLifters Included:YesLifter Style:Hydraulic flat tappetValve Springs Included:NoRetainers Included:NoLocks Included:NoValve Stem Seals Included:NoTiming Chain and Gears Included:NoAssembly Lubricant Included:YesPushrods Included:NoRocker Arms Included:NoGaskets Included:NoQuantity:Sold as a kit.Cam and Lifters, Hydraulic Flat Tappet, Advertised Duration 282/282, Lift .465/.465, Chevy, Small Block, Kit



thats the cam i got and i have 1.6s with it. now your seaying sumit didnt sell me the right cam.

Ronny

iTrader: (1)

my 224/230 @114 is a dog under 2500 rpms. 350 cid. wont cruise at 1500 rpms in 5 gear. little power little TQ. a manual trans. so i fell that helps me. unfortunately 3.05 gears. also if i try to cruise at 1500 rpms, and i do, the A/F gets a bit funky on WB even though BLM's are 124 in those areas. i still say the funky WB readings are being influenced by cam. log looks like a roller coaster. i am running a rich tune but NB pulls the excess fuel. without a good tune i dont see how that car will run very well .

t-rex_camaro

im going to get a good tune. i gust have to find someone that knows how to do it becas i dont whant to do it my self im a hands on guy not a computer wizz. i would screw thing up.

BMmonteSS

What I'm saying is that if the car runs and drives fine, doesn't buck, miss and bog all over itself then maybe some how you got confused on what part number the cam was. It's been done before, but after seeing lots of cars have all kinds of drivability problems with a cam thats a full 20 deg smaller, I know for a fact that you should be having some problems.

Ronny

iTrader: (1)

i put my car on dyno. it was not cheap. to find a tuner that has experience in TBI applications may be difficult. paying an hourly labor rate may be cost prohibitive. plus they need the equiptment to burn. local dyno by me sees mostly carb cars(off street) and a few newer modded foreign and domestic. i saw the files. i bet i was the only customer that ran a TBI on his dyno. i dont recalll anyone tuning TBI on a dyno. usually done on the street. i will suggest these cars were rarely tuned back in the 80's when they were manufactured. this forum and crossfireforum is your best bet. first step is an ALDL cable(moates), download winALDL on laptop (to log and recognize problem flags), and watch the results at idle in neutral when engine over 180 deg. that is the simple part. who do you know that has a laptop?

alternative is carb it. but that is costly too.

Fast355

iTrader: (2)

There was a company called Traco Engineering that did build a L03 in the late 80s. They went as far as to burn their own proms and make it run well. They ran a 14.27 @ 96.6 in a Full weight Camaro with a moded L03, back in 1989. The whole story ran in Octobor/November 1989 issues of Hot Rod magazine. Unfortunately Traco Engineering went under about the same time, putting the TBI world out of luck for many more years.

Ronny

iTrader: (1)

i would love to know how many burns it took. i will assume a dyno tune. WOT flying down the 1/4 may be easy to tune. a daily driving routine tune may be a greater chalange. EBL/Prominator/8746 with IAT coming UPS today. Guess I need to relearn a few things.

t-rex_camaro

it did run like **** when we first broke in the cam but we played with the timing and got it to idle and run fine. i dont think the #s are wrong unles someone at sumit messed up becas i orderd it off there website. i didnt call. i always order off there website its faster for me. i have guys telling me on diff websites that this cam is a littil small compared to the cams they ran in there 305s back in the day.

t-rex_camaro

ok im willing to give buring a shot but where do i buy the stuff i need to burn. all the software and what not

Fast355

iTrader: (2)

They put the L03 on an engine dyno, ran it before and after. They initially put on edelbrock headers/L-69 dual snorkel w/K&N, and advanced the timing. They ran at the track before and after those mods. They returned the engine to stock ran it, then went back to those mods and dyno'd it again. They then used a custom ground cam, stock L98 aluminum heads, standard carb performer intake with an adapter plate (found just as I have that the 3704 gives more torque than HP), and the shorty headers. They ended up with 350 injectors and lots of prom tweaking. They found another 97 FWHP in the L03.

Stock was 174 HP @ 4,800 and 266 ft/lbs @ 2,400. With the bolt-ons it made 181 HP @ 4,800 and 275 ft/lbs @ 2,000. After Traco's magic, it made 270 FWHP @ 5,000 and 306 FWTQ @ 3,600 rpm. That was with the crappy edelbrock TES system for a L03 engine. To bad that the dual cat LB9/L98 system was not substituted!

t-rex_camaro

thats cool i will be ordring new heads when school starts up. but till then im gust going to drive my car. thanks for all the info