Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   Thunder bolt IV timing question (https://www.offshoreonly.com/forums/general-q/254147-thunder-bolt-iv-timing-question.html)

87MagnumII 05-22-2011 06:59 PM

Thunder bolt IV timing question
 
Anybody know what rpm the TBIV ignition reaches full advance? Also how much advance can you squeeze out of these units

FIXX 05-22-2011 08:28 PM

Fixx
 

Originally Posted by 87MagnumII (Post 3409626)
Anybody know what rpm the TBIV ignition reaches full advance? Also how much advance can you squeeze out of these units

that depends on the number on the module..if its a V8-24 then the 24 is the degrees + your base timing..if you put more base timing in then your advance will be higher..
8*+24* = 32* total..

the number will be stamped on the side..

Griff 05-23-2011 01:11 AM

The rpm for full advance depends on which TB IV module you have. Depending on the module, it can be anywhere between 3000rpms and 5000rpms.

Thunderstruck 05-23-2011 08:29 AM


Originally Posted by Griff (Post 3409981)
The rpm for full advance depends on which TB IV module you have. Depending on the module, it can be anywhere between 3000rpms and 5000rpms.

Absolutely, the SC motors had different curves than the NA motors so you need to do some research on where the module came from.

kreed 05-23-2011 09:01 AM

Does the preset # of the module ONLY matter when setting base timing? When setting total advance timing, does the -24 or -14 matter? Just bring up the RPM's til you see it stop advancing and set it at 34 degrees?? Sound right?

87MagnumII 05-23-2011 10:35 AM


Originally Posted by Thunderstruck (Post 3410124)
Absolutely, the SC motors had different curves than the NA motors so you need to do some research on where the module came from.

It's a v8-24 unit from a 260hp 5.7L. I upgraded to vortech iron heads, performer rpm intake, 9.8:1 compression, the lt4 hot cam with roller rockers and a 650 demon carb, I was wondering how much timing this setup will want.

Griff 05-23-2011 11:59 AM


Originally Posted by kreed (Post 3410164)
Does the preset # of the module ONLY matter when setting base timing? When setting total advance timing, does the -24 or -14 matter? Just bring up the RPM's til you see it stop advancing and set it at 34 degrees?? Sound right?

Yes, that will work. Total advance is more important than base timing.


Originally Posted by 87MagnumII (Post 3410274)
It's a v8-24 unit from a 260hp 5.7L. I upgraded to vortech iron heads, performer rpm intake, 9.8:1 compression, the lt4 hot cam with roller rockers and a 650 demon carb, I was wondering how much timing this setup will want.

The V8-24 is at full advance around 3500-3700rpms.

rexcramer1 05-23-2011 01:14 PM


Originally Posted by 87MagnumII (Post 3410274)
It's a v8-24 unit from a 260hp 5.7L. I upgraded to vortech iron heads, performer rpm intake, 9.8:1 compression, the lt4 hot cam with roller rockers and a 650 demon carb, I was wondering how much timing this setup will want.

With 9.8 compression you dont want too much advance. It also depends on if you want to run premium fuel all the time or not.

Start at 32 degrees total advance and you can make small adjustments up from there. I doubt you will be able to run more than 36 degrees, and too much advance will cause detonation

87MagnumII 05-23-2011 03:41 PM


Originally Posted by rexcramer1 (Post 3410452)
With 9.8 compression you dont want too much advance. It also depends on if you want to run premium fuel all the time or not.

Start at 32 degrees total advance and you can make small adjustments up from there. I doubt you will be able to run more than 36 degrees, and too much advance will cause detonation

Cool deal. I plan on running premium gas anyways but was told the vortecs don't like anymore than 34

Griff 05-24-2011 01:08 AM


Originally Posted by 87MagnumII (Post 3410610)
Cool deal. I plan on running premium gas anyways but was told the vortecs don't like anymore than 34

Actually more like 30* for vortec heads.


All times are GMT -5. The time now is 01:45 AM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.