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How is everyone running so much boost?


Nick7
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I was wondering how is everyone running so much boost, but I hear nothing about no one doing anything with timing to keep from den.? I was just wondering, because I would like to run more boost, but scared too with nothing other than a Blaster 2 coil, Msd 8.5mm wires and ngk plugs and ot other way of advancing or retarding timing for more boost? any help would be helpful.. thanks
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the stock distributor has a vacuum advance, it also functions as a boost retard...

 

ok.. well i know that much, but isnt 18lbs on a 19C alittle to much for stock TBI with all the mods that I have?

 

non-jetted head, 1mm ss os valves, heady duty valve springs, 274 Billtet cam ported and ported head with five angle port valve job. port intake manifold, port turbo 19C and exhaust manifold, open 2.5 inch exhaust, ARP head studs and ajusa head gasket, new crankshaft, race-prepped rods, .020 over weisco pistons 8:1. block decked, head shaved. all steel braided lines, all hard piping, MAFT. Blaster 2 Coil, 8.5mm wires, NGK plugs. Walbro 255 inline pump, Fuel cell, AFPR, aftermarket boost gauge and Aem wideband that will be in tommarrow dang hopefully. The whole block has all new timing part and OEM oil pump, ARP's. Dual stage boost controller. What else do I need to run more boost, I have a new Vaccum advance. Pulls hard, but want more boost on TBI. my dyno number were 241tq at 3300rpms and 225hp at 5800rpms. I would like to get my hp up to 250 and tq to 300 is I can.. I hope this helps?

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I believe he read it as boost, retard, not boost retard ( as in opposite of boost/reversing things ) on accident'

 

but as Chad said, vacuum advance is it. Also, ~15psi isn't a lot today ( ask the supra folk who run 30-40psi )

 

If you want ot hit the 250 mark well, I didn't see anything about tuning stuff. Ever considered the MAFT at least? I know you've been asking about MPI

Edited by Fanta
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boost retard = opposite of vacuum advance

 

ok. my timing is hitting dead on 10 degrees BTdC and advancing no more then 30 degrees. Which is better then what the stock dizzy is suppose to do I believe. Still I would like to know what u guys are doing to get so much hp on stock tbi. take Truth for instance hes getting 245hp at 313 tq. This would be nice if I could get it. but hes boosting 19psi?

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ok. my timing is hitting dead on 10 degrees BTdC and advancing no more then 30 degrees. Which is better then what the stock dizzy is suppose to do I believe. Still I would like to know what u guys are doing to get so much hp on stock tbi. take Truth for instance hes getting 245hp at 313 tq. This would be nice if I could get it. but hes boosting 19psi?

 

He's also running the GM MAS with the DSM MAFT - so he essentially tuned in his A:F ratio's to make the maximum HP ( from a DIY driveway standpoint ). You have a great TBI setup, you really need to tune it honestly to pull the most from it.

Edited by Fanta
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I believe he read it as boost, retard, not boost retard ( as in opposite of boost/reversing things ) on accident'

 

but as Chad said, vacuum advance is it. Also, ~15psi isn't a lot today ( ask the supra folk who run 30-40psi )

 

If you want ot hit the 250 mark well, I didn't see anything about tuning stuff. Ever considered the MAFT at least? I know you've been asking about MPI

 

I listed it. I have a MAFT to tune with. I want to go mpi but money is the issue right now at this time..

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I listed it. I have a MAFT to tune with. I want to go mpi but money is the issue right now at this time..

 

 

whoops, I missed it, so disregard my previous post as well then. Did you have the AEM wideband previously? or just a wideband o2 sensor and gauge to read to tune with the MAFT accurately?

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whoops, I missed it, so disregard my previous post as well then. Did you have the AEM wideband previously? or just a wideband o2 sensor and gauge to read to tune with the MAFT accurately?

 

lol. well my wideband was suppose to be in today. but it didnt. I had it tuned on a dyno with wideband.

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wow think you could be any more of an a**...he just wanted some help.

 

Perhaps you don't understand the simplicity of the question, so you can't comprehend the simplicity of the answer.

 

He wants to run more boost but is concerned the timing assembly will not compensate.

 

The vacuum advance retards timing as it sees boost. It's a linear process. Add more boost, it pulls more timing out (retard) If stock pulls 10* at 15 PSi, you can expect it to pull about 20* at 30 PSI.

 

Upping the boost required better fuel, but does not require a major distributor overhaul or expensive timing gizmos.

 

Those can help you runmore boost at higher intake temps (if you have an inefficent turbo),bu thte stock distributor is well timed for more boost bone stock.

 

Do you understand that now that I have over-expalined a simple device starwolf?

 

Nick7, the stock distributor will change timing as needed. If you are concerned, focus that on your air/fuel mixtures. If you run a higher grade of fuel (race gas) you can run a LOT more timing than the stock setup allows. It's a conservitive (safe) setup.

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Perhaps you don't understand the simplicity of the question, so you can't comprehend the simplicity of the answer.

 

He wants to run more boost but is concerned the timing assembly will not compensate.

 

The vacuum advance retards timing as it sees boost. It's a linear process. Add more boost, it pulls more timing out (retard) If stock pulls 10* at 15 PSi, you can expect it to pull about 20* at 30 PSI.

 

Upping the boost required better fuel, but does not require a major distributor overhaul or expensive timing gizmos.

 

Those can help you runmore boost at higher intake temps (if you have an inefficent turbo),bu thte stock distributor is well timed for more boost bone stock.

 

Do you understand that now that I have over-expalined a simple device starwolf?

 

Nick7, the stock distributor will change timing as needed. If you are concerned, focus that on your air/fuel mixtures. If you run a higher grade of fuel (race gas) you can run a LOT more timing than the stock setup allows. It's a conservitive (safe) setup.

 

ok. that kool. I was getting some spark knock a week ago and I ran race fuel and it went away. however I have fixed them problems so I can run 93 octane. Chad what size bigger injectors do u recommend for 18lbs on a 19C with my mods. I was thinking about delphi's 85lbs for primary and 95lbs. for secondary. But I wonder if they are direct fit?

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I don't know how well the car will run when you size them that way, the stock ECU is mapped out for a secondary that is 2x's teh size of teh primary. You can get it tuned with your mods for that 85# primary, but wil will be expecting the secondary to be twice the size, so it will lean out up top. I suppose you can tweak your mods, but getting the balance just right will be trial and error, and the error part may ruin your motor. 65# primaries with 95# secondaries seems to be about the best you can do reliably.

 

If you realy want more fuel, you'll need a 3rd injector and a computer to run it.

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air + fuel = power.

of coarse in tune.

what other methods of tuning do you have?

you might just go stand alone, cause you can always use that when you go mpi.

IMHO megasquirt is a great option. fully tunable, fuel and spark.

I've personally ran it tbi and mpi. the same box.

if you have any question you can pm me.

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I don't know how well the car will run when you size them that way, the stock ECU is mapped out for a secondary that is 2x's teh size of teh primary. You can get it tuned with your mods for that 85# primary, but wil will be expecting the secondary to be twice the size, so it will lean out up top. I suppose you can tweak your mods, but getting the balance just right will be trial and error, and the error part may ruin your motor. 65# primaries with 95# secondaries seems to be about the best you can do reliably.

 

If you realy want more fuel, you'll need a 3rd injector and a computer to run it.

 

18lbs of boost is all I want to run on the 19C for now. So u think 65lbs for primary and 95lbs for secondary will be enough. of course with a tune!

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wow think you could be any more of an a**...he just wanted some help.

 

 

hahaha, this has to be a joke. it cracked me up either way. yeah, man, that was funny

 

anyway, yeah the primary point of the thing really is to retard timing on boost, not to advance timing on vacuum. A car with a failed vacuum advance modulator diaphram will idle fine, but hit a brick wall on boost as the timing fails to retard. pre-ignition is about like slapping the top of the piston with a hammer as it's trying to come up so the car falls on its face. The vacuum diaphram system really isn't reliable enough for big boost situations

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18lbs of boost is all I want to run on the 19C for now. So u think 65lbs for primary and 95lbs for secondary will be enough. of course with a tune!

 

 

just remember you've never really tuned anything on TBI. The flow characteristics of the stock intake manifold don't allow for consistent distribution of air and fuel to all cylinders above about 14psi. I admit that I'm pulling that number out of thin air but it's based on 15 years of observation about when these motors blow and which cylinders typically fail. If you want to run 18psi, and you want to be safe, you need MPI. You can run 18psi and you can tune away, but the A/F ratio you see on the gauge, read after the turbo, will not be the A/F ratio in all 4 cylinders on TB injection above "about" 14psi boost. It's just not possible. You will always be reading average a/f ratio of all 4 cylinders which means the center two will be richer and the outside two will be leaner. The center two cylinders are fed through a more direct intake manifold runner path than the outer two. For the outer two the air fuel mix has to turn slightly, or travel farther or something, doesn't matter. All you need to know is it's enough to effect them and "something" consistently causes number 1 and 4 rod bearing failures. Again, this is speculation but somewhat common knowledge about our stock intake and a rather good bet considering how many engines fail by spinning rod bearings on number 4. It is typically leaner and therefore more prone to detonation (hammer strikes) and more prone to kill a bearing.

Edited by chiplee
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hahaha, this has to be a joke. it cracked me up either way. yeah, man, that was funny

 

anyway, yeah the primary point of the thing really is to retard timing on boost, not to advance timing on vacuum. A car with a failed vacuum advance modulator diaphram will idle fine, but hit a brick wall on boost as the timing fails to retard. pre-ignition is about like slapping the top of the piston with a hammer as it's trying to come up so the car falls on its face. The vacuum diaphram system really isn't reliable enough for big boost situations

 

so what do u recommend

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no actually i did read the post wrong and either way i am semi stupid when it comes to these things.

 

i just heard from other people that a lot of a** holes linger on this site.

 

i find it helpful and was just astonished thinking someone with such an early date and post said something like that.

 

i can get flamed for this i dont mind.

 

sorry chad hope i got some laughs out of you guys.

 

:D cheers

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no actually i did read the post wrong and either way i am semi stupid when it comes to these things.

 

i just heard from other people that a lot of a** holes linger on this site.

 

i find it helpful and was just astonished thinking someone with such an early date and post said something like that.

 

i can get flamed for this i dont mind.

 

sorry chad hope i got some laughs out of you guys.

 

:D cheers

 

a-holes? pfft, this site has a great base, but yes some personalities clash with each other - but props to you for apologizing

 

Nick7 - for a 19C I do agree with chip - I'd recommend maybe turning the boost back down some ( say 12-15psi - at the end of the start of 19c's efficiency range) and tune it for that till you can save up for MPI.

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no actually i did read the post wrong and either way i am semi stupid when it comes to these things.

 

i just heard from other people that a lot of a** holes linger on this site.

 

i find it helpful and was just astonished thinking someone with such an early date and post said something like that.

 

i can get flamed for this i dont mind.

 

sorry chad hope i got some laughs out of you guys.

 

:D cheers

 

I know I laughed my a** off.

 

Don't forget to check your timing... ...retard. LMAO...

 

BTW, you'll soon easilly see who the tails are.

 

-Robert

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