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which intake and carb
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jhyjohnson
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Joined: 30 Oct 2005
Posts: 129

4780.54 points


1973 Buick Apollo

PostPosted: Tue May 16, 2006 5:27 pm    Post subject: Reply with quote

i have shimmd the rear end with the 2 degree wedge plates, have used 2 per side. i agree with car 2 high but just dont have the room for tires at stock height. guess i try and take out middle spring and try to get it back down. [/list][/list]
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disturbthepeace1
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Joined: 14 Jun 2003
Posts: 303
Location: Stanton, CA
10195.60 points


1965 Volkswagen Beetle

PostPosted: Tue May 16, 2006 11:15 pm    Post subject: Reply with quote

this might be a retarded question but how are you launching this car? are you flashing the converter? power braking to the stall point? i have gotten better 60ft times in cars with bald tires... you might want to paint a strip on the tires, take her out to a open road, and have a buddy watch you luanch... you say you have no tire spin but i cant see you cutting that kind of time without spin.....
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artinla
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Joined: 09 May 2006
Posts: 233

8558.30 points


1971 Chevrolet Nova

PostPosted: Wed May 17, 2006 4:50 am    Post subject: Reply with quote

I am not sure that I agree that wheelspin is your main problem. You said the car launches good and only a little spin. If it is getting off the line with only a little spin, you are OK since 90% of your wheelspin is going to occur right on the line unless you are running some crazy multi stage n20 or something, which I assume you are not. I think you may need to have someone check that your total ignition timing is around 34 degrees and that your cam is not installed in the advanced position. Your car is obviously laying down at higher RPM and that points toward ignition or cam timing.

What kind of distributor and headers are you running? After a hard run, kill your engine ASAP and check the plugs. If they are anything darker than a chocolate brown, you probably should jet down a little. The goal is between cream and very light brown. No black, no shine. Watch for little purplish balls on the ceramic, if you see those you went too far. Also, what power valve does the Holley have in it?
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jhyjohnson
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Joined: 30 Oct 2005
Posts: 129

4780.54 points


1973 Buick Apollo

PostPosted: Wed May 17, 2006 7:22 am    Post subject: Reply with quote

i launch the car by powerbraking to around 2500. i have tried to flash the converter but get horrible spin and wheel hop. as far as the power valve im not for sure just borrowed the carb and put it on. we timed the car by feel. held the throttle to 2500rpm found best idle. car was little hard to start so advanced it barely so it would start. im running an accell supercoil HEI and billet distributor. when you talk about intial timing and all in by ? rpm how do you do this. im really appreciating the lesson guys thanx
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beersngars
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Joined: 04 Feb 2006
Posts: 390
Location: Ohio
13369.80 points


1948 Chevrolet Coupe

PostPosted: Wed May 17, 2006 7:43 am    Post subject: Reply with quote

jhyjohnson wrote:
i launch the car by powerbraking to around 2500. i have tried to flash the converter but get horrible spin and wheel hop. as far as the power valve im not for sure just borrowed the carb and put it on. we timed the car by feel. held the throttle to 2500rpm found best idle. car was little hard to start so advanced it barely so it would start. im running an accell supercoil HEI and billet distributor. when you talk about intial timing and all in by ? rpm how do you do this. im really appreciating the lesson guys thanx


Got a few questions here. You say that you adjusted the car for best idle @ 2500 rpm? Shocked Adjusted what? You need to get the idle set down to around 1000 rpm. Right now it sounds like you are trying to get the thing to idle on the mains. Then you need to disconnect the vacuum advance, and set the timing to 10 degrees and then slowly rev the motor to about 3000 rpm. Using a light the timing should come up to around 34 degrees. To make this 34 degree total timing occur sooner or later, you will have to try other springs or weights. Also you need to experment as to if your combo likes more initial timing or more on the distributer.
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Aerosmith
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Joined: 25 Dec 2002
Posts: 232
Location: Ohio
7771.70 points



PostPosted: Wed May 17, 2006 11:50 am    Post subject: Reply with quote

I've never had a (fast) leaf spring car, but it's my understanding that you need to make sure that when you do get the slapper bars contacting the leaf springs that they need to be contacting at the leaf eye and not on the leaf itself, which I have read binds the leaf and offsets any gains. I can relate to the "get your rearend out of the air" thing. to run the 29" street tire I use(to help offset the 4.10 gear) I have TRW cargo coils and air lift drag bags on my Camaro. Someday I would like to try some 26" slicks and drop the rear to stock height. The problem with lifting the rear end is it turns the pinion upward which is counter to what we are trying to accomplish. I've heard 1-2 degrees down is a good starting place? You are able to set the pinion with shime between the axle and leaves, I think they come in 2 and 4 degrees from Lakwood. Yes I was right, I just checked..$19.99 a pair from Jegs, 2 or 4 deg.
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artinla
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Joined: 09 May 2006
Posts: 233

8558.30 points


1971 Chevrolet Nova

PostPosted: Wed May 17, 2006 4:23 pm    Post subject: Reply with quote

Good info from the guys above, do what they suggest. I have a couple more questions before I pass judgement on the engine. As for the timing, you have to have someone with a degree wheel set up a mark for you on the balancer. Ask them to put one for TDC, one for 32 and one for 34 degrees.
With a timing light, rev the engine until the lines stop moving around. You want to turn the distributor to get the total advance (while still revving to a point high enough to stabilize the mark) to 34 degrees. Run the 32 degree mark if it is particularly cool outside or if you are going to run nitrous. Even 30 degrees would be better for N20. The springs that determine what RPM is required to get all the advance in by a certain RPM are under the rotor. Looser springs get the timing in quicker, stiffer ones take longer. There are also ways to change bushings and grind certain parts of the weights to customize the advance curve. Study the mechanism and you will see how it works. I have had the best luck with medium or light springs, just buy an advance curve kit, it comes with a selection of springs and bushings. Usually they come with new weights too.

It looks to me like you have a cam designed for high rpm and the rest of your engine is more for torque. With the gears you are running, I think you need to focus your attention on airflow in the engine. You have a restriction somewhere. I am guessing that you are running unported stock or double hump heads, and probably have very small tube headers. Also, I suspect you have a dual plane intake, and you probably should be running a single plane with that engine, cam and those gears.

So.. What heads are you running? What Headers, and What intake. Also, have you done any porting, matching or bowl work on the heads?
What size are the valves.

Art
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Paul P
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Joined: 15 Aug 2002
Posts: 2403
Location: Townsend, Mass.
81574.74 points


1971 Chevrolet Chevelle

PostPosted: Wed May 17, 2006 4:29 pm    Post subject: Reply with quote

The first post in this subject answers most of your questions about the motor. Burn Out
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af2
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Joined: 01 Sep 2003
Posts: 5558
Location: grassvalley, ca
71227.76 points


1933 Willys Coupe

PostPosted: Wed May 17, 2006 4:52 pm    Post subject: Reply with quote

Paul P wrote:
The first post in this subject answers most of your questions about the motor. Burn Out


I agree! He has to address the issue he stated earlier on leaving the line. He should be able to flash the converter and go without blowing the tires off and wheel hopping. With out preload on the bars he is screwed. By the way leaving the Pinion down 1 to 2 degrees only makes up for the twist. If every thing is correct it should be at 0.
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jhyjohnson
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Joined: 30 Oct 2005
Posts: 129

4780.54 points


1973 Buick Apollo

PostPosted: Wed May 17, 2006 7:14 pm    Post subject: Reply with quote

Got a few questions here. You say that you adjusted the car for best idle @ 2500 rpm? Shocked Adjusted what? You need to get the idle set down to around 1000 rpm. Right now it sounds like you are trying to get the thing to idle on the mains. Then you need to disconnect the vacuum advance, and set the timing to 10 degrees and then slowly rev the motor to about 3000 rpm. Using a light the timing should come up to around 34 degrees. To make this 34 degree total timing occur sooner or later, you will have to try other springs or weights. Also you need to experment as to if your combo likes more initial timing or more on the distributer.[/quote]

ok car does idle at 1000rpm. guy at the track was helping with timing. he held throttle at around 2500rpm and set distributor at smoothest point. but at this setting the car was to hard to start so we had to advance the timing slightly to get car started. also i already have 4 degrees of shims per side and the traction bars do make contact under the leaf eye. i will get a spring kit for the distributor and while i have tranny out this weekend will pull middle leaf out of the springs. so should i go bak to the torkerII single plane or keep the rpm air gap dual plane. guess i will get some more shims for the traction bars also. guess i need to introduce myself to the timing light. lol
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af2
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Joined: 01 Sep 2003
Posts: 5558
Location: grassvalley, ca
71227.76 points


1933 Willys Coupe

PostPosted: Wed May 17, 2006 7:21 pm    Post subject: Reply with quote

af2 wrote:
Paul P wrote:
The first post in this subject answers most of your questions about the motor. Burn Out


I agree! He has to address the issue he stated earlier on leaving the line. He should be able to flash the converter and go without blowing the tires off and wheel hopping. With out preload on the bars he is screwed. By the way leaving the Pinion down 1 to 2 degrees only makes up for the twist. If every thing is correct it should be at 0.


I will Quote one more time If you can't leave the line you are done Confused
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artinla
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Joined: 09 May 2006
Posts: 233

8558.30 points


1971 Chevrolet Nova

PostPosted: Thu May 18, 2006 1:14 am    Post subject: Reply with quote

Go back to the single plane, get the timing to 34 degrees, make sure your headers are around 1 3/4" primaries, and have someone who knows what they are doing to properly jet your carb. I suspect that you are very rich, check for a blown power valve. If you do all of that you should be in the high 7's. If you pulled the heads and did a little pocket porting and matching, you might get into the low 7's, assuming your valve springs are heavy enough to avoid valve float. I have a 71 Nova SS and I just can't see your Apollo doing much better than a 1.5-1.7 60ft time considering that you have a torque motor coupled with 5.13's. The gears seem a little low for your engine combo, 4.11 or 4.56 seems a more logical choice for an airflow restricted setup such as yours. I say again, you aren't going to lower your 1/8th mile time 2 seconds (which is what you need to do) by gaining .4 secs or so at the 60ft mark (wheelspin isn't a factor by then).

Your car is laying down at higher RPM, and that is going to require more than shims or adjusting slappers. If you want REAL gains, consider buying a top shelf set of heads such as the AFR 195's. That is where I would spend my money, and also ditch the hydro cam.
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af2
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Joined: 01 Sep 2003
Posts: 5558
Location: grassvalley, ca
71227.76 points


1933 Willys Coupe

PostPosted: Thu May 18, 2006 6:52 pm    Post subject: Reply with quote

jhyjohnson wrote:
i launch the car by powerbraking to around 2500. i have tried to flash the converter but get horrible spin and wheel hop. im really appreciating the lesson guys thanx


I say no more!
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af2
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Joined: 01 Sep 2003
Posts: 5558
Location: grassvalley, ca
71227.76 points


1933 Willys Coupe

PostPosted: Thu May 18, 2006 7:11 pm    Post subject: Reply with quote

jeep_406 wrote:
I wouldn't touch the engine set-up until you get the car to hook. Taking care of that problem would probably put you in the 7's in the 1/8th mile.


Just another one!!! Start from the problem and work you're way up. Stop throwing $$$$$ to fix the problem you still have.
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jhyjohnson
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Joined: 30 Oct 2005
Posts: 129

4780.54 points


1973 Buick Apollo

PostPosted: Fri May 19, 2006 4:22 pm    Post subject: Reply with quote

trust me i have learned an expensive lesson by throwing money at it and still having the same problem when im finished. ive got a buddy with sum different rims with better back spacing so i can move the tires under the fenders more so i can try to take out a leaf and get the rear of the car down some more. i emaild edelbrock and they said go back to the single plane and run a 2inch spacer so i will try that also. i do appreciate everyones suggestions as i learn about this.
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