Crank Trigger Question - Chevelle Tech
Performance Our High Performance area

 6Likes
Reply
 
LinkBack Thread Tools Search this Thread Display Modes
post #1 of 17 (permalink) Old Nov 18th, 19, 6:38 PM Thread Starter
Tech Team
 
Join Date: Aug 2019
Posts: 34
Crank Trigger Question

Building my drag race only big block and i have a msd digital 7+(7520 not 7531) box. I keep hearing that crank trigger are the best for timing accuracy at higher rpm and was wondering if there is any difference with a locked distributor. As i understand locked distributor wouldn't fluctuate but hey maybe i'm uninformed. I can get the msd crank trigger at a good price and wouldn't mind getting it for peace of mind.
GabLeGrand is offline  
Sponsored Links
Advertisement
 
post #2 of 17 (permalink) Old Nov 18th, 19, 8:17 PM
Senior Tech Team
 
Join Date: Apr 2012
Location: Yerington, Nevada
Posts: 1,803
Re: Crank Trigger Question

Crank trigger doesn't vary in signal area, but, timing chain, cam end play can alter timing signals, even with a locked out distributor.
GabLeGrand likes this.
Dave Ray is offline  
post #3 of 17 (permalink) Old Nov 18th, 19, 8:45 PM
Lifetime Premium Member
Jeff
 
Join Date: Feb 2008
Location: PuebloWest, CO.
Posts: 6,185
Re: Crank Trigger Question

Got to go with Dave on this one he is 100% correct.
GabLeGrand likes this.

78 Malibu, 402, eddy heads, 174 B&M blower, th350, holley sniper EFI, 9" 3:70, 26X8.50-15 slicks.
69 VW baja 1679cc. stick shift toy.
96 chevy 1500, tow vehicle.
03 yz85 fun bike.
04 scion XB daily driver.
Jebchevelle is offline  
 
post #4 of 17 (permalink) Old Nov 18th, 19, 8:59 PM
Senior Tech Team
 
Join Date: Dec 2005
Location: Lancaster, PA
Posts: 10,981
Re: Crank Trigger Question

The trigger is the best. What are your goals with this car? As great as a lot of parts are itís easy to turn an affordable race car into one that isnít.
bradley67 and GabLeGrand like this.

Ray


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Best pass 8.87 at 150.98 1.212 60'. Sold 3/2018

1970 SS 396 project in progress. Bought 5/2018
bracketchev1221 is offline  
post #5 of 17 (permalink) Old Nov 18th, 19, 9:17 PM Thread Starter
Tech Team
 
Join Date: Aug 2019
Posts: 34
Re: Crank Trigger Question

Alright then! Seems that i was thinking wrong. Might as well get it now than later
GabLeGrand is offline  
post #6 of 17 (permalink) Old Nov 18th, 19, 9:27 PM Thread Starter
Tech Team
 
Join Date: Aug 2019
Posts: 34
Re: Crank Trigger Question

Quote:
Originally Posted by bracketchev1221 View Post
The trigger is the best. What are your goals with this car? As great as a lot of parts are itís easy to turn an affordable race car into one that isnít.
I'm not really making it the most affordable strip car since i'm building it over long term and still want it to be kind of reliable(i mean no ebay parts). I don't mind paying little extra for some insurance. I'm building a high compression 496 and trying to make ~800hp n/a on race gas, still gathering parts for it and waiting for big sales
GabLeGrand is offline  
post #7 of 17 (permalink) Old Nov 18th, 19, 10:01 PM
Senior Tech Team
 
Join Date: Dec 2005
Location: Lancaster, PA
Posts: 10,981
Re: Crank Trigger Question

If you can afford it go for it. I never bought one. I ran my 565 with an advancing msd distributor and nothing else. I donít know if the trigger was worth any power. I made 980 without the trigger.

Ray


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Best pass 8.87 at 150.98 1.212 60'. Sold 3/2018

1970 SS 396 project in progress. Bought 5/2018
bracketchev1221 is offline  
post #8 of 17 (permalink) Old Nov 18th, 19, 10:19 PM
Lifetime Premium Member
Jason
 
Join Date: Sep 1998
Location: Highland Village TX, USA
Posts: 3,115
Re: Crank Trigger Question

My timing light says a crank trigger is more stable and consistent. I have never tested the power difference though.
DragRacer is offline  
post #9 of 17 (permalink) Old Nov 19th, 19, 1:29 AM
Tech Team
Chris
 
Join Date: Apr 2010
Location: Calgary, Alberta, Canada
Posts: 901
Re: Crank Trigger Question

Quote:
Originally Posted by GabLeGrand View Post
Building my drag race only big block and i have a msd digital 7+(7520 not 7531) box. I keep hearing that crank trigger are the best for timing accuracy at higher rpm and was wondering if there is any difference with a locked distributor. As i understand locked distributor wouldn't fluctuate but hey maybe i'm uninformed. I can get the msd crank trigger at a good price and wouldn't mind getting it for peace of mind.

I wouldn't waste my money on a crank trigger expecting power gains of any sort. A digital 7 plus box can complete individual cylinder timing. I would put my money towards the fibre optic pickup and put your time and effort into individual cylinder timing. I completed this on my big block and some cylinders were off as much as 5 degree. ALL 8 cylinders were off the base timing mark on my setup. you want some extra HP, invest here not a crank trigger. best bang for the buck.


to complete the task you will need the fibre optic cam sync, PN is in your instructions. As well a dial back timing light.


utilizing the timing light set the timing with a dial back, to 0 that is, is the easiest. use a pipe tape, tape measure for measuring diameter of pipe, and circle it around the balancer starting at zero. measure your distance and divide by 8, then mark then distances on the pipe tape location. You will have a 0 mark for each cylinder. From here you just move the timing light to each plug wire and adjust it as needed in the MSD software.

1968 Beaumont
502 big block
Stock looking, definitely not stock sounding
HP and ET not determined yet!
GoFast Beaumont is offline  
post #10 of 17 (permalink) Old Nov 19th, 19, 6:15 AM Thread Starter
Tech Team
 
Join Date: Aug 2019
Posts: 34
Quote:
Originally Posted by GoFast Beaumont View Post
Quote:
Originally Posted by GabLeGrand View Post
Building my drag race only big block and i have a msd digital 7+(7520 not 7531) box. I keep hearing that crank trigger are the best for timing accuracy at higher rpm and was wondering if there is any difference with a locked distributor. As i understand locked distributor wouldn't fluctuate but hey maybe i'm uninformed. I can get the msd crank trigger at a good price and wouldn't mind getting it for peace of mind.

I wouldn't waste my money on a crank trigger expecting power gains of any sort. A digital 7 plus box can complete individual cylinder timing. I would put my money towards the fibre optic pickup and put your time and effort into individual cylinder timing. I completed this on my big block and some cylinders were off as much as 5 degree. ALL 8 cylinders were off the base timing mark on my setup. you want some extra HP, invest here not a crank trigger. best bang for the buck.


to complete the task you will need the fibre optic cam sync, PN is in your instructions. As well a dial back timing light.


utilizing the timing light set the timing with a dial back, to 0 that is, is the easiest. use a pipe tape, tape measure for measuring diameter of pipe, and circle it around the balancer starting at zero. measure your distance and divide by 8, then mark then distances on the pipe tape location. You will have a 0 mark for each cylinder. From here you just move the timing light to each plug wire and adjust it as needed in the MSD software.
I would not buy the crank trigger for power gains but more for a higher rpm safety since i'll might push it a bit sometimes. Never heard of that system and definetly worth to take a look at it 👍
GabLeGrand is offline  
post #11 of 17 (permalink) Old Nov 19th, 19, 8:52 AM
Tech Team
Brian
 
Join Date: Aug 2009
Location: Michigan
Posts: 765
Garage
Re: Crank Trigger Question

I hooked up a crank trigger this year for the first time and not only is the timing light steady, but on my car it starts easier with way less kick back.

Power wise who knows, but it didn't hurt it


Brian

66 chevelle
New Combo
555
10.2 comp
Straub ProMaxx heads
Straub solid roller
TH400/373
3815lbs
1.31 60'
[email protected]
[email protected]


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
B433 is offline  
post #12 of 17 (permalink) Old Nov 19th, 19, 9:23 AM
Senior Tech Team
Rick
 
Join Date: Nov 2006
Location: Langhorne, Pa
Posts: 4,208
Re: Crank Trigger Question

Quote:
Originally Posted by GoFast Beaumont View Post
I wouldn't waste my money on a crank trigger expecting power gains of any sort. A digital 7 plus box can complete individual cylinder timing. I would put my money towards the fibre optic pickup and put your time and effort into individual cylinder timing. I completed this on my big block and some cylinders were off as much as 5 degree. ALL 8 cylinders were off the base timing mark on my setup. you want some extra HP, invest here not a crank trigger. best bang for the buck.


to complete the task you will need the fibre optic cam sync, PN is in your instructions. As well a dial back timing light.


utilizing the timing light set the timing with a dial back, to 0 that is, is the easiest. use a pipe tape, tape measure for measuring diameter of pipe, and circle it around the balancer starting at zero. measure your distance and divide by 8, then mark then distances on the pipe tape location. You will have a 0 mark for each cylinder. From here you just move the timing light to each plug wire and adjust it as needed in the MSD software.
I've seen an engine make more power on an engine dyno and chassis dyno. Usually upper rpm, but enough power gain to justify it's cost.

1967 Chevelle Malibu 4 door


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


The 7.99 at 173mph pass:


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


8.02 at 171mph:


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Calculated Risk is offline  
post #13 of 17 (permalink) Old Nov 19th, 19, 12:09 PM
Lifetime Premium Member
Dan
 
Join Date: Aug 2007
Location: orange county
Posts: 10,093
Re: Crank Trigger Question

Quote:
Originally Posted by DragRacer View Post
My timing light says a crank trigger is more stable and consistent. I have never tested the power difference though.
Exactly, crank trigger according to the timing light is rock steady.

'66 SS Chevelle
565 BBC Mamofied 300cc Ovals
4.11 12 bolt
Best e.t. to date [email protected] @115.31
1.301 60' 3355 pbr 1.306 3055S
Stokerboats is offline  
post #14 of 17 (permalink) Old Nov 19th, 19, 1:44 PM
Senior Tech Team
Scott Foxwell
 
Join Date: Dec 2008
Location: N/E Tennessee
Posts: 3,792
Re: Crank Trigger Question

There would be no sense in trying individual cylinder timing and NOT using a crank trigger. Way too much inconsistency using a distributor. Cam twist, valve train, timing chain, oil pump harmonics, all at the back of the cam, then trying to control timing using a distributor...not good. There is a reason modern engines don't use distributors any more. Crank trigger for any decent race engine should just be a given. Same with a vac pump. Two things I tell my customers...if you want to make the most power you can, you need those two things. Foundational.

FOXWELL MOTORSPORTS
Straub Technologies

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
steelcomp is offline  
post #15 of 17 (permalink) Old Nov 19th, 19, 4:52 PM
Senior Tech Team
 
Join Date: Apr 2012
Location: Yerington, Nevada
Posts: 1,803
Re: Crank Trigger Question

The main reason today's engines use individual, sequential ignition systems is that fun word we all just LOVE....EMISSIONS. Varying the timing in the wrong way makes for more emissions output, with the problem of making less power.

It is all in emissions efficiency and fuel control. When we developed the first HEI's when I worked on that project at GM, the premise was to build an ignition that would need absolutely low maintenance, along with not changing the timing at all during that period, so emissions wold not be increased. So, we designed and developed the large HEI, to replace points systems that changed with every spark plug firing from wear on points rubbing blocks and condition of points contact faces.

If anyone has tinkered with a points distributor for enough to get frustrated with it, they know that when they go into setting the system, they find a dwell change, and the timing they left the system at, retarded. And, during the maintenance, simply resetting the dwell back to the original spec, which would have been done at the service before, brought the timing right back to where it was the last service. I see it all the time, dwell set to 30 degrees, timing set to proper degrees. 10K miles later, dwell is changed, as is timing. Simply returning the dwell to the original 30 degrees, brings the timing straight back to where it was last set, service interval previous.

Electronic ignitions were designed to NOT allow the tiimng spec to change as miles were driven, eliminating one facet of emissions levels increasing. Those electronic systems have evolved into help for our engines along the way, they help increase performance.


If you have an older car that still has a points distributor, you can have some fun learning, set the dwell and timing, then, leave the dwell meter connected, and use the Allen screw to change the dwell as the engine runs, record the timing changes on the balancer, then, bring the dwell back to the original spec. Amazing how a bit of dwell change, changes the entire engine performance by also changing the timing.
steelcomp likes this.
Dave Ray is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevelle Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address. Note, you will be sent a confirmation request to this address.

Email Address:
OR

Log-in










Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome