 Timing your V8-914 / ATT: V8 Guys!, any body got any good hints or suggestions? |
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| wallys914 |
 Dec 20 2009, 05:31 PM
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#1
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In life you don't get what you want, you get what you negoia  Group: Members Posts: 190 Joined: 10-October 08 From: Garden Grove, Member No.: 9,631 Region Association: Southern California  |
I set my motor up and everything is running great, but I can feel a like it has a lil hesitation.Without throwing a light on it, I cant get rid of it. I know that the distributor is off, just enough to effect perfection.
How have the V8 guys set up there 914's so that they can time them with easy? Thanks, |
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Replies(1 - 18)
| Cheapsnake |
Dec 20 2009, 06:53 PM
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#2
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Member Group: Members Posts: 419 Joined: 15-November 07 From: Door County, WI Member No.: 8,341 |
Unless your advance curve is woefully flat I wouldn't think your hesitation is due to timing. Hesitation is usually traced to a fuel issue and my guess is that you're not getting a quick shot of fuel when you step on it. Most carbs have different settings for the accelerator pump, ranging from a short stroke to a long stroke and one or two positions in between. Check to see where you're at and adjust for longer stroke if possible.
Otherwise, it may be a lean jetting problem, which will require a bit more work, but still a very manageable problem. If you are running lean, get it corrected before you have more problems than a hesitation. Good luck. Tom |
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| messix |
Dec 20 2009, 06:56 PM
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#3
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AKA "CLUTCH KILLER"! Group: Members Posts: 6,995 Joined: 14-April 05 From: between shit kickers and pinky lifters/ puget sound wa.north of Seattle south of Canada Member No.: 3,931 Region Association: Pacific Northwest |
hesitation when? tip in no load? part throttle cruise? heavy acceleration? what carb are you running?
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| Mike Bellis |
Dec 20 2009, 09:37 PM
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#4
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Resident Electrician Group: Members Posts: 8,345 Joined: 22-June 09 From: Midlothian TX Member No.: 10,496 Region Association: None 
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Get a vacuum gauge. connect to the intake, move dizzy until you get the highest vac reading at idle. Mark the dizzy at this position. play with advancing and retarding from that mark.
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| TC 914-8 |
Dec 20 2009, 10:24 PM
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#5
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Senior Member Group: Members Posts: 812 Joined: 23-May 08 From: Sequim, WA Member No.: 9,090 Region Association: Pacific Northwest
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QUOTE(messix @ Dec 20 2009, 04:56 PM)  hesitation when? tip in no load? part throttle cruise? heavy acceleration? what carb are you running? Troy is on to something, we need more info. Also I agree with " Cheapsnake" It is probally a carb issue. I have the same hesitation when I'm at cruse then punch it too fast. Something I live with, Accelerate smothely. I also use the Vaccume timming method, get the highest vaccume at idle then back it down 1". Also in the Rod Simpson install handbook. |
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| messix |
Dec 21 2009, 12:44 AM
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#6
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AKA "CLUTCH KILLER"! Group: Members Posts: 6,995 Joined: 14-April 05 From: between shit kickers and pinky lifters/ puget sound wa.north of Seattle south of Canada Member No.: 3,931 Region Association: Pacific Northwest |
QUOTE(TC 914-8 @ Dec 20 2009, 09:24 PM) QUOTE(messix @ Dec 20 2009, 04:56 PM) hesitation when? tip in no load? part throttle cruise? heavy acceleration? what carb are you running? Troy is on to something, we need more info. Also I agree with " Cheapsnake" It is probally a carb issue. I have the same hesitation when I'm at cruse then punch it too fast. Something I live with, Accelerate smothely. I also use the Vaccume timming method, get the highest vaccume at idle then back it down 1". Also in the Rod Simpson install handbook. we need to look at the power vavle on your carb. might have to move down some on it. |
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| computers4kids |
Dec 21 2009, 09:30 AM
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#7
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Love these little cars! Group: Members Posts: 2,443 Joined: 11-June 05 From: Port Townsend, WA Member No.: 4,253 Region Association: None |
QUOTE(TC 914-8 @ Dec 20 2009, 08:24 PM) QUOTE(messix @ Dec 20 2009, 04:56 PM) hesitation when? tip in no load? part throttle cruise? heavy acceleration? what carb are you running? Troy is on to something, we need more info. Also I agree with " Cheapsnake" It is probally a carb issue. I have the same hesitation when I'm at cruse then punch it too fast. Something I live with, Accelerate smothely. I also use the Vaccume timming method, get the highest vaccume at idle then back it down 1". Also in the Rod Simpson install handbook. Intitially, I tried to time my engine with a light, and I thought I was giving it plenty of advance. I drove the the car for quite a while like this. Thanks to Tony (TC 914-8), I tried timing a while back using the vaccum method...huge difference in performance---my motor needed a ton more initial advance. However, my car didn't have hesitation issues. I also purchased an adjustable vaccum advance thinking I was going to adjust the curve along with diff. dizzy weights, but the car ran so great after the timing change I just left it alone. You're problem sounds more related to fuel. If you can't sort it out, you might consider adding a air fuel mixture gauge (even temporarily) and drive your car under a lot of conditions and see what the mixture is doing when you experience the hesitation. Give us more info... |
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| wallys914 |
Dec 21 2009, 06:39 PM
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#8
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In life you don't get what you want, you get what you negoia Group: Members Posts: 190 Joined: 10-October 08 From: Garden Grove, Member No.: 9,631 Region Association: Southern California |
Thanks guys I will take a look at the fuel delivery. To give a little more info on the carb and motor it is a 650 dp mech sec over proformer RPM manifold, into a 88 350 with a 488 cam with MSD ignition and Dizzy, eventually on 100 shot of N2O. The carb is brand spanking new as well as the MSD set up. I really have only timed it by ear, so that's why I feel like the timing would fix the major issues. I want to get it timed so I can try the Nitrious out... (IMG:style_emoticons/default/biggrin.gif)
I think I will try COMP4KIDS idea about the air/fuel gauge Might be good with the Nitrious anyways (IMG:style_emoticons/default/rolleyes.gif) ... and then try the vacuum timing procedure. Thanks again... |
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| messix |
Dec 21 2009, 07:04 PM
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#9
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AKA "CLUTCH KILLER"! Group: Members Posts: 6,995 Joined: 14-April 05 From: between shit kickers and pinky lifters/ puget sound wa.north of Seattle south of Canada Member No.: 3,931 Region Association: Pacific Northwest |
QUOTE(wallys914 @ Dec 21 2009, 05:39 PM) Thanks guys I will take a look at the fuel delivery. To give a little more info on the carb and motor it is a 650 dp mech sec over proformer RPM manifold, into a 88 350 with a 488 cam with MSD ignition and Dizzy, eventually on 100 shot of N2O. The carb is brand spanking new as well as the MSD set up. I really have only timed it by ear, so that's why I feel like the timing would fix the major issues. I want to get it timed so I can try the Nitrious out... (IMG:style_emoticons/default/biggrin.gif) I think I will try COMP4KIDS idea about the air/fuel gauge Might be good with the Nitrious anyways (IMG:style_emoticons/default/rolleyes.gif) ... and then try the vacuum timing procedure. Thanks again... if your gonna hit it with no2 you will need to pull timing out of it, or get a timing retard that is triggered when the no2 is on. do some research on it or you will frag the motor [not all at once but over time]. the dp is most likely going to give you fits on the street and a vac secondary would be tamer. and the cam is 488 lift? what is the .05 duration? you can play with the accelarator pump cam [the plastic thingy by the throttle linkage that pushed the pump arm] it will have a couple of screw holes for different settings. and does the carb have idle mixture screws on the secondary side? |
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| TC 914-8 |
Dec 21 2009, 07:38 PM
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#10
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Senior Member Group: Members Posts: 812 Joined: 23-May 08 From: Sequim, WA Member No.: 9,090 Region Association: Pacific Northwest
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What is this "Dizzy" you talk about ? Sounds like a Centrufugal advance?
If you plan on hitting that engine with nitrous, I'm hoping you have a 915, G50 or 930 transaxle. The 901 is only good up to 375Ft/lbs TQ. |
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| TC 914-8 |
Dec 21 2009, 07:58 PM
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#11
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Senior Member Group: Members Posts: 812 Joined: 23-May 08 From: Sequim, WA Member No.: 9,090 Region Association: Pacific Northwest
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QUOTE(messix @ Dec 20 2009, 10:44 PM) QUOTE(TC 914-8 @ Dec 20 2009, 09:24 PM) QUOTE(messix @ Dec 20 2009, 04:56 PM) hesitation when? tip in no load? part throttle cruise? heavy acceleration? what carb are you running? Troy is on to something, we need more info. Also I agree with " Cheapsnake" It is probally a carb issue. I have the same hesitation when I'm at cruse then punch it too fast. Something I live with, Accelerate smothely. I also use the Vaccume timming method, get the highest vaccume at idle then back it down 1". Also in the Rod Simpson install handbook. we need to look at the power vavle on your carb. might have to move down some on it. The Edlebrock I have has the metering rods which I have put in lighter springs to keep them closed at idle and open at 5-6" vac. Also, changed rods 1 step leaner at cruse, ( I was 2 steps lean at cruse) Someday, next spring I'll have her out for a drive and see what new problem arises. The Holley 650DP should be a simple fix, check the web site for a chart for the PV vac. setting, check what your carb was sent with or open a float bowl and the vac setting should be stamped on the PV, which screws into the metering block. Then hit the speed shop for a lighter PV. That should help. |
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| marks914 |
Dec 21 2009, 08:17 PM
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#12
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Senior Member Group: Members Posts: 845 Joined: 9-October 04 From: the motor city Member No.: 2,912 Region Association: None |
advance the timing until you have a ping, then back it off, if the starter won't kick it over then back it off a bit more-done.
Yeah, the NOS will blow your trans apart. Mark |
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| wallys914 |
Dec 21 2009, 09:13 PM
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#13
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In life you don't get what you want, you get what you negoia Group: Members Posts: 190 Joined: 10-October 08 From: Garden Grove, Member No.: 9,631 Region Association: Southern California |
You guys think the NOS will blow the trans? Even if applied from a roll, in 4th and 5th?
There are some guys running 400hp on a 901, right? |
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| Rand |
Dec 21 2009, 09:38 PM
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#14
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Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
Sounds like you have a handle on it Wally. I'm not a NOS kinda guy in a 914 application. But think about it, when would you use it? When you are done running through the gears, it's pulling hard in a high gear, and you want a boost, right? That's not the time it's going to blow the trans.
With a v8, in the low gears, you aren't going to have time to hit it. Besides it would be pointless unless you have some massive meats to hook up. And then I would hope you wouldn't shift into third, and hit NOS while popping the clutch. |
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| JDJim |
Dec 21 2009, 10:16 PM
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#15
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Newbie Group: Members Posts: 2 Joined: 22-November 09 From: Auburn, CA Member No.: 11,061 Region Association: Northern California |
QUOTE(Rand @ Dec 21 2009, 07:38 PM) Sounds like you have a handle on it Wally. I'm not a NOS kinda guy in a 914 application. But think about it, when would you use it? When you are done running through the gears, it's pulling hard in a high gear, and you want a boost, right? That's not the time it's going to blow the trans. With a v8, in the low gears, you aren't going to have time to hit it. Besides it would be pointless unless you have some massive meats to hook up. And then I would hope you wouldn't shift into third, and hit NOS while popping the clutch. |
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| TC 914-8 |
Dec 21 2009, 10:50 PM
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#16
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Senior Member Group: Members Posts: 812 Joined: 23-May 08 From: Sequim, WA Member No.: 9,090 Region Association: Pacific Northwest
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QUOTE(wallys914 @ Dec 21 2009, 07:13 PM) You guys think the NOS will blow the trans? Even if applied from a roll, in 4th and 5th? There are some guys running 400hp on a 901, right? I used to think it was all about the HP, I spent an hour or so on the phone with Rod Simpson one day. He made it real clear thru the many, many conversions he has done, rate the transaxle on torque. anything over 375 ftlbs tq, I would need a 915. The No2 is fine if your on a drag strip, and have a trans and engine to handle it. |
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| marks914 |
Dec 22 2009, 07:27 AM
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#17
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Senior Member Group: Members Posts: 845 Joined: 9-October 04 From: the motor city Member No.: 2,912 Region Association: None |
QUOTE(wallys914 @ Dec 21 2009, 10:13 PM) You guys think the NOS will blow the trans? Even if applied from a roll, in 4th and 5th? There are some guys running 400hp on a 901, right? I am running well over 400 HP through my 901. Its fine as long as you don't beat on it. If you are going to put on the juice when in higher gear, where will you be doing this? My car winds out at 150 in 4th somewhere around 180 in 5th. Mark Attached thumbnail(s) 
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| wallys914 |
Dec 22 2009, 03:01 PM
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#18
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In life you don't get what you want, you get what you negoia Group: Members Posts: 190 Joined: 10-October 08 From: Garden Grove, Member No.: 9,631 Region Association: Southern California |
(IMG:style_emoticons/default/mellow.gif) All Valid Points! I will take the NOS into consideration once I get the bugs worked out. Thanks guys!
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| messix |
Dec 22 2009, 03:47 PM
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#19
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AKA "CLUTCH KILLER"! Group: Members Posts: 6,995 Joined: 14-April 05 From: between shit kickers and pinky lifters/ puget sound wa.north of Seattle south of Canada Member No.: 3,931 Region Association: Pacific Northwest |
no2 builds big tourque as soon as it hits, think about it this way... it's spraying at a constant rate along with fuel so your gonna get the big hit at lower rpm and and not so much at higher rpm.
i dare you to keep a clutch alive spraying it! (IMG:style_emoticons/default/happy11.gif) i don't like the advance til it pings rule, and the time it by vac can have problems too. you can buy a degreed timming tape that sticks to the ballencer and make or buy an adjustable pointer and get it to tdc find a place that you can mount the pointer on the bottom side and then attach the tape so the poiter is at tdc. then you can put the car on stands or ramps and time it from the bottom [you'll still have to get up ad adjust the diz a little at a time. best starting point on a average sbc is 36% at 3,000 rpm make sure its all in by then. then goof around with it from there. |
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