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| Pontiac - Boost Turbo, supercharged, Nitrous, EFI & other Power Adders discussed here. |
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#1
11-01-2016, 07:22 PM
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Boost snd timing #
Ok I need to know how much timing I can run with my turbo Pontiac 468 and 15# of boost and I am running e85 for fuel I current have my timing locked at 32 and pulling 9 degrees out at 2psi of boost for a total of 23 with boost. Does this sound good or should it be lower ??
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#2
11-01-2016, 08:47 PM
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You're fine if you ask me. Just make sure your air inlet temperature is good.. try keeping it below 190. At that boost level you should have no problem keeping it below 140
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My Half AN Injun..... |
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#3
11-01-2016, 10:24 PM
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It is a very loaded question. Cam, compression? Air fuel under 11.7.
With e85 all being in check Charlie's answer is correct. Start lower keep reading your plugs as you go up in boost. I would start at 6psi and work up from there. |
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#4
11-02-2016, 06:24 AM
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Thanks guys well my intentions were to to start at 8 psi but my test run the boost went to 15 and it feels too good so that's were I am going to start ....what the limiting factor on how much to go up to Charlie ?? And as I creep up to 20 psi do I still need to take more timing out? On a side note my new Fitech fuel injection system is working flawless with e85
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#5
11-02-2016, 07:21 AM
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Quote:
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My Half AN Injun..... |
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#6
11-03-2016, 07:31 PM
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What heads? An iron Dport isn't going to take the timing an Ehead will for example.
__________________
The secret to happiness is not getting what you want but rather, wanting what you have. |
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#7
11-03-2016, 09:00 PM
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With proper tuning of the engine and cooling of the heads, (not rust buckets inside), most engines Pontiac, Ford, Chebby, Chrysler (be it cast iron or aluminum) can live with 24 to 27 degrees of boosted timing all day long even at much higher boost pressures.
This assumes good cooling of the intake charge, (inter-cooler, methanol injection, etc). Blow thru (non inter-cooled) engines even with E-85 have to be careful with inlet temps being a serious factor in pre-ignition/detonation in the engine. Timing is also very touchy where you can "fall off the cliff" and hurt stuff with a one degree timing mistake. Head gaskets, torched combustion chambers, etc. Reading plugs properly is essential. Do not assume that the air/fuel (HEGO SENSOR) is the only thing to monitor. You can make mistakes with Air/Fuel and get away with it. Timing mistakes will kill parts immediately. Ask Charlie to tell you his wisdom on timing and how being TIMING conservative has helped his save parts over the years. Tom V.
__________________
"Engineers do stuff for reasons" Tom Vaught Despite small distractions, there are those who will go Forward, Learning, Sharing Knowledge, Doing what they can to help others move forward. |
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#8
11-05-2016, 08:08 PM
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Timing with boostc
Heads are iron running E85 plus a front mount Intercooler I know that e85 cools the intake charge by itself and is hard to detonate , if I keep raising the boost up do I keep the timing the same ?
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#9
11-05-2016, 09:46 PM
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You'll probably find a happy spot between 20-25deg with that setup in the 15-20psi range you mention. Tom's advice on timing hurting parts faster than fueling is right on the money too... that extra degree is tempting, but with boost and alcohol fuel it can be costly. I tune mine by the plugs - here's a link to a good article on how.
http://www.dragstuff.com/techarticle...ark-plugs.html Here's also a pic of one of mine that demonstrates what I believe is a safe tuneup. Note the cad is about 75% burned off on the face, and the timing mark is slightly short of the bend. This pic was taken from my hottest cylinder after 2 full 1/4 mile passes. Hope this helps - gdlk!
__________________
The secret to happiness is not getting what you want but rather, wanting what you have. |
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#10
11-06-2016, 03:18 AM
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Torment- can I assume that plug was running race gas? If I saw that plug in a blown-alky engine I'd go two steps colder on plugs.
I just bumped my old thread in the 'RACE' forum to the top- if anybody's got any comments about timing for my blown 4-cylinder hemi.
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Anybody else on this planet campaign a M/T hemi Pontiac for eleven seasons? ... or has built a record breaking DOHC hemi four cylinder Pontiac? ... or has driven a couple laps of Nuerburgring with Tri-Power Pontiac power?(back in 1967) ... or has a Pontiac born the same year as Jim Wangers? (1926} 
Last edited by Jack Gifford; 11-06-2016 at 03:40 AM. |
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#11
11-06-2016, 08:06 AM
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Thanks tourment but any experience with e 85? I assume your running race gas ?
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#12
11-06-2016, 11:25 AM
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Quote:
Tom V.
__________________
"Engineers do stuff for reasons" Tom Vaught Despite small distractions, there are those who will go Forward, Learning, Sharing Knowledge, Doing what they can to help others move forward. |
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#13
11-06-2016, 04:35 PM
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__________________
John Wallace - johnta1 Pontiac Power RULES !!! www.wallaceracing.com Winner of Top Class at Pontiac Nationals, 2004 Cordova Winner of Quick 16 At Ames 2004 Pontiac Tripower Nats KRE's MR-1 - 1st 5 second Pontiac block ever! "Every man has a right to his own opinion, but no man has a right to be wrong in his facts." "People demand freedom of speech to make up for the freedom of thought which they avoid." – Socrates |
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#14
11-06-2016, 06:29 PM
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That plug is an NGK -10 and was run with VP M1 methanol, but I previously ran E85 - I didn't treat plug reading any different. With E85 however, I did look for no more than 50% burned off the face in any single 1/4 mile pass. I didn't run it quite as lean as I will with the VP M1 fuel.
Tom - sorry... I'm not too good with links/internet in general. I 'previewed' the post and it seemed to work - dunno.
__________________
The secret to happiness is not getting what you want but rather, wanting what you have. |
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#15
11-06-2016, 06:40 PM
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Quote:
__________________
The secret to happiness is not getting what you want but rather, wanting what you have. |
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#16
11-06-2016, 06:44 PM
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__________________
The secret to happiness is not getting what you want but rather, wanting what you have. |
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#17
11-06-2016, 06:57 PM
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Poorfectly! As "Curly" Howard (from the 3 stooges) would say!
 Tom V.
__________________
"Engineers do stuff for reasons" Tom Vaught Despite small distractions, there are those who will go Forward, Learning, Sharing Knowledge, Doing what they can to help others move forward. |
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