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Author Topic:   need more coming off
racer17j
Member
posted May 02, 2004 12:09 PM
any ideas to get some more comming off the corner without changing gear or cam here's what i have
355 flatop 882's with 2.02/1.6 valves 1.5 long slots push rods are +.100
1.46 springs seat is 120#@1.875 open 395#@1.175
313 intake
510/510 244/244@.050 108 centers hydro cam installed straight up
speedway rochester 2 brl
timing 38*
my rules are 360 cid 9-1 comp and any hydro cam. i'm just wonding id going one way or the other with the cam or maybe going to lighter z-28 spirings might help


gould
Member
posted May 02, 2004 06:53 PM
as cold as it was last night do you fatten up the carb jetting?

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racer17j
Member
posted May 02, 2004 07:31 PM
i didn't have my jets with me so no but i considered that. but my plugs looked perfect so i didn't want to mess with that


LUBEGUY07
Member
posted May 02, 2004 08:05 PM
how old is your distributor and coil? check your timming angain with timming light and run the rpms up and down and hold it steady and she if it jumps around. also how many rpms were u turning comming out of conner and were it it start to fall flat? I used to run that same cam and switched to a smaller one , and i thought it was much stronger out off the coners, also how old is timming chain when they get old and strech they do the same thing. hope this helps


Flatlander
Member
posted May 02, 2004 09:49 PM
chain is new all the dist parts are good yet they don't move at all under the timing light holds steady right on the line all the way. i was kinda thinking of going back to my 480 that i ran when i had my malibu body on the car. i'm not sure what i was turning coming off was to busy tring to dodge ruts to watch the tach lol. i realise i was getting pulled by a guy running a 383 but i was right with sterm in the 24 just needed a little more off and on restarts it kinda lags. if i can get some parts sold i think i will go to a different cam either another 480 or the one that matt byrne y5 and cory roe 8r was running toftee is running that now and he got 3rd with it in hobby in mason city so i know that one will work lol


FFMM
Member
posted May 03, 2004 08:10 AM
Did u degree the cam in or just put in straight up? i would recommend retarding it as much as 8 degrees will give u more bottom end. What kind of carb. do u run? might want to try another power valve or accelerator pump cam. or accel pump. just some ides


awkwardjeff
Member
posted May 03, 2004 09:30 AM
Here is my take on the deal, You want MORE off the corner but everyone seems to be talking about a stumble in the motor....did I miss something??? It sounds like the motor runs fine correct??? You just want more off the corner...

A ton of people don't carry good corner speed and think the motor is LAZY off the corner, personally I would work on the chassis for two reasons. If you carry 10 mph MORE in the corner that will translate into 15-18 mph at the end of the straight. Also you don't seem to want to change gears or cam, so I take that as you don't want to tear into the MOTOR.........

I also think the valves are too big for 9 to 1 compression, along with the heads being used...... a 2.02 vavle is too big for the cam you are running. I would like to have MORE information on the cam before I make that statement, But I would think the duration adv. is about 278-282 is that about right??? I also believe a cam change is in order to HELP create more torque off the corner, but you stated you didn't want to change cams, Someone else replyed THEY would retard the cam as much as 8 degrees. WOW thats a bunch....... I personally would advance the cam 4 degrees......and MY thinking is from the point of view of the valves being too big would help balance the intake charge with the heads. I KNOW normally retarding a cam will help with torque numbers, But in this case I believe the opposite is true because of the valve size. I would like to know the differance from adv. duration to .050 to see the ramp profile of the cam, there MAYBE some room to improve with a 1.6 rocker.


quote:
Originally posted by racer17j:
any ideas to get some more comming off the corner without changing gear or cam here's what i have
355 flatop 882's with 2.02/1.6 valves 1.5 long slots push rods are +.100
1.46 springs seat is 120#@1.875 open 395#@1.175
313 intake
510/510 244/244@.050 108 centers hydro cam installed straight up
speedway rochester 2 brl
timing 38*
my rules are 360 cid 9-1 comp and any hydro cam. i'm just wonding id going one way or the other with the cam or maybe going to lighter z-28 spirings might help



dirtbuster
Member
posted May 03, 2004 09:54 AM
Advancing a cam helps bottom end while retarding it helps top end, so i dont know why you would want to retard it. A lot of cams already have advance built into them from the factory so are you sure its straight up? Did you degree it or did you just use the zero marks on the timing set and assume straight up? I would have that cam advacned 4 degrees if it were mine and it wasnt built in.

Changing springs wont help, in fact it will prob hurt.

ARe you sure its a lack of power or did you need to work on chassis setup. REally you are pretty limited in what you can do to the motor without opening it up to change cams. Changing gears would prob be your best bet but if you dont want to do that then your kind of limited to what you have.

racer17j
Member
posted May 03, 2004 07:22 PM
opening the motor up or changing gears wouldn't bother me a bit it's just my wallet thats telling me no. i have to run a t-350 and have to run a gm rear end i have a 3.73 in 2nd so the next step is pretty drastic in a 4.11 that would mean new rear tires and wheels or turn 7000+ and i don't want to do that. i could go with a smaller gear in first but last time i tried that i shucked a tranny after 2 nites. the carb is a speedway 1 3/8 bore rochester 2 brl and cam is a 187r speedpro.which i installed just button on button. handling wise i couldn't ask for any more out of it the track has been terible and i'm the only car in my class that can put it on the bottom where there is no ruts and make it stick thats where i passed 95% of the cars last week was when they would push and hit the ruts. i have a fealing the track will be this rough for a while and the bottom is going to be the smoothest way around so i want to be able to beat them off when they push in the middle and off. the one car i faught with for the last 5 laps would pull me big time going out then would push and hit a rut in the middle and i would pull even and a fender ahead but once he got it gathered back up i got smoked if i could have pulled with him off i could have moved him up to the top for one lap and he'd have been in all the ruts and been history and maybe a couple more but he pulled me so bad i couldn't catch him till about 1-2 car lenghts from the corner and by that time he was down in my line and i didn't dare move up for the huge ruts would have just killed me and probably my tires as well.i was real tempted to use the old chrome horn but i try to drive as clean as i can . this thing is such a dog i can't even spin the tires on wet pavment i tried to burn the tires off after i washed the car and it just kinda chugged a bit then when it gets up over 3500 or so then it kicks in but on this one lane stuff as soon as it kicks i got to slow her down my tach maxed out at 5300 and i was lifting about 3/4 of the way down the shoot on a small 1/2 it's 1/2 on the outside with 12 * banking and pretty sweeping corners. i do have a set of 1.6 rockers but was kinda scared to go that hi of lift on this i realize i may be jumping the gun here since it was just the first nite and realy only have 10 racing laps on and came from 20th to 8th with it but i'm getting real tired of haveing the best hadling car but getting out powered all the time

[This message has been edited by racer17j (edited May 03, 2004).]

iowa_dirt_track_girl
Member
posted May 03, 2004 07:52 PM
I would say to put your 1.6 rockers on the intake e-mail me with your total cam specks cause the 202 valves on the 882 heads dont produce that much torque as iam sure you know a smaller valve makes more torque but not much rpm

You really need to turn about 6000 or so for your cam to work good cause you probably pull reall good about 100 foot off the corner as you said so a little more gear would be the best even if it is slick you have the car setup and the foot finese to not spin the tires when i raced at your track it took a way diffrent gear then most tracks like that

racer17j
Member
posted May 03, 2004 08:27 PM
opening the motor up or changing gears wouldn't bother me a bit it's just my wallet thats telling me no. i have to run a t-350 and have to run a gm rear end i have a 3.73 in 2nd so the next step is pretty drastic in a 4.11 that would mean new rear tires and wheels or turn 7000+ and i don't want to do that. i could go with a smaller gear in first but last time i tried that i shucked a tranny after 2 nites. the carb is a speedway 1 3/8 bore rochester 2 brl and cam is a 187r speedpro.which i installed just button on button. handling wise i couldn't ask for any more out of it the track has been terible and i'm the only car in my class that can put it on the bottom where there is no ruts and make it stick thats where i passed 95% of the cars last week was when they would push and hit the ruts. i have a fealing the track will be this rough for a while and the bottom is going to be the smoothest way around so i want to be able to beat them off when they push in the middle and off. the one car i faught with for the last 5 laps would pull me big time going out then would push and hit a rut in the middle and i would pull even and a fender ahead but once he got it gathered back up i got smoked if i could have pulled with him off i could have moved him up to the top for one lap and he'd have been in all the ruts and been history and maybe a couple more but he pulled me so bad i couldn't catch him till about 1-2 car lenghts from the corner and by that time he was down in my line and i didn't dare move up for the huge ruts would have just killed me and probably my tires as well.i was real tempted to use the old chrome horn but i try to drive as clean as i can . this thing is such a dog i can't even spin the tires on wet pavment i tried to burn the tires off after i washed the car and it just kinda chugged a bit then when it gets up over 3500 or so then it kicks in but on this one lane stuff as soon as it kicks i got to slow her down my tach maxed out at 5300 and i was lifting about 3/4 of the way down the shoot on a small 1/2 it's 1/2 on the inside with 12 * banking and pretty sweeping corners. i do have a set of 1.6 rockers but was kinda scared to go that hi of lift on this i realize i may be jumping the gun here since it was just the first nite and realy only have 10 racing laps on and came from 20th to 8th with it but i'm getting real tires of haveing the best hadling car but getting out powered all the time


Flatlander
Member
posted May 03, 2004 08:56 PM
we realy can't do anything to the carb.last year with this cam stock 882's with z-28 springs and a 2.28 in first gear it would turn great 6400 at wc 6200 at britt was realy good but after i blew that tranny i went to the 3.73. maybe i need to pop the cover and count the gear to be sure i never did count it just went by the stamp i have found a few that where off. i still have the 2.28 which comes out to be a 5.74 and have a 2.41 which would be a 6.07 i run 81 and 79 in roll most guys are running 4.11/6.24with a 86 in or 12 bolts with 586and 83 in roll the hobby stock mostly run 6.0 with 83's but those guys turn um pretty hard i can't afford to build a new motor so i need to make this one last all year again

[This message has been edited by racer17j (edited May 03, 2004).]

dirtbuster
Member
posted May 03, 2004 09:27 PM
Most guy I know running cams similar to that are turning 6500-7000.Since you are only turning 5300 you either need more gear to get the rpms up to where the cam will work better or you need to change the cam to match your rpms. I would think going from a 3.73 to a 4.11 in the same tranny gear with the same size tires and wheels would prob get you 500 rpm, which could make a big difference. Personally i think the gear change would prob perform betteR.
Also dig out your cam card and see if there is any advance built into the cam. If not go ahead and advance it 4 degrees. Do both and I'd bet youd notice a big difference.


tech355
Member
posted May 04, 2004 04:21 PM
i'm in nc iowa hamilton county speedway.dirtbuster last year it turned 6500 which is right where i want to be but with it not coming off the corner and haveing to slow down so soon for the corners is why it only turned 5300. when the track getrs worked in i will more then likely run the top side and a 6.24 gear would be to dang much

[This message has been edited by racer17j (edited May 04, 2004).]

racer17j
Member
posted May 04, 2004 10:34 PM
here is the rest of the cam info i can find

318/318dur @.006 and over lap is 94 it's a pro serries 5000

Raz_900
Member
posted May 05, 2004 01:34 PM
Swap the cam for a 230/230 @.050" and you'll be amazed. You're about 1000 rpm under the cam's powerband. Could change the gear to get up into the 6200-6500 rpm range as well. Anything less will be below the cams max HP rpm.

No matter what's wrong with everything else... you still have a 4000-6500 rpm cam meant for a 11:1 motor in a 9:1 3500-5500 rpm motor.


rico 08
Member
posted May 05, 2004 02:30 PM
As raz said you have a little too much cam,my motor is very similar 'cept for cam and compression:355,882's,11-1,234-244 @.050 112* LC.I have not raced it yet but the driveway tests tell me it's not lazy on the bottom,the compression really helps.I'd either put on some really short tires or order a new cam.


gould
Member
posted May 05, 2004 08:03 PM
i turn 6600rpm with my 9 to 1 2 bbl motor

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www.geocities.com/gouldracing11


racer17j
Member
posted May 05, 2004 09:57 PM
raz if it isn't a one lane stop and go track on the bottom i do turn 6500 if i can run the top side but having nothing off the corner i can't get my speed built up my next choice of gears would put me at 7000 max and thats to hi i may try to degree this one in and i think i can find a 4.11 and try till the rreack shapes up maybe i can win some money then and get some new tires and keep running it


awkwardjeff
Member
posted May 06, 2004 12:06 AM
IS THAT CORRECT 318 DURATION AT .006..........I DON'T THINK SOOO. THAT THING WOULD NOT RUN IF THOSE NUMBERS WERE TRUE. AND IF THE FIRST POST IS CORRECT WITH 244 DURATION AT .050 (WHICH I BELIEVE TO BE TRUE) THAT WOULD GIVE YOU 72 DEGREES OF SPLIT, FROM .050 TO .006 THAT SPLIT IS NORMALLY ABOUT 30 DEGREES.... SO SOME WHERE, SOME HOW THOSE NUMBERS ARE WAY OFF. Did you read the cam card, or try to figure it out another way???

From the sounds of it all NOW you know what you need to do.......change gears or tires for a few weeks until you can move up the track to carry more speed in the turns.

quote:
Originally posted by racer17j:
here is the rest of the cam info i can find

318/318dur @.006 and over lap is 94 it's a pro serries 5000




racer17j
Member
posted May 06, 2004 03:44 PM
i don't have the cam card those are the numbers i got off speed pro's web site i was looking at my buddies comp card for his cam and it is real close except for that on his it's 284 int 296 exe @006 so i was think'n that sounded kinda funny too since most of the other specs are all within 006 of each other


dirtbuster
Member
posted May 07, 2004 07:27 AM
I dont doubt that it is 318 @ .006 and 244 @ .050. A lot of older design cams had a lot of duration at .006 like that. They have really gentle ramps on them so there is a big difference between the .006 and .050 numbers. That is why the newer cams perform so much better They keep the difference between the 2 around 30-40 degrees different. When looking at a cam, the closer the advertised or .006 duration is to the .050 duration the more aggressive the cam is. I would bet you could find a newer cam w/ same duration @.050 but with .006 numbers around 280.


racer17j
Member
posted May 07, 2004 10:48 PM
think i got her figured out and man do i feal stupid in my heat it was cutting out 1/2 way down the shoots well turned out my float wasn't set right so i was running the bowl out so before the main i fixed it the first time i went to far tho car started then ran for a couple seconds and blew fuel out the bypass well i got it adjusted right but needless to say i never changed or looked at the plugs got to doing my weekly checks tonite and the plugs are as wet as could be lol thanks for the help guys maybe it's more then just the plugs but i have my fingers crossed that this is the problem


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