pump gas limit

[95ttalontsi]

How do you "know" if you have reached the max boost of turbo on pump gas. Ive been messing around with boost level on my hx35 and at around 30psi logs are showing 52lb/min airflow but since im on the evo 8 stock timing maps it feels slow as its dropping into about 7* total timing with about 2* from 4000 to 5500 rpm, but if i add 1* timing from 4000 up i get 2 degrees of knock. So should i lower boost to like 24-5 psi so i can have 13* total timing.

 

[GSXDNA]

How do you "know" if you have reached the max boost of turbo on pump gas. Ive been messing around with boost level on my hx35 and at around 30psi logs are showing 52lb/min airflow but since im on the evo 8 stock timing maps it feels slow as its dropping into about 7* total timing with about 2* from 4000 to 5500 rpm, but if i add 1* timing from 4000 up i get 2 degrees of knock. So should i lower boost to like 24-5 psi so i can have 13* total timing.

30psi is a ton of boost for pump, and 7 degrees is low for timing. I'd lower your boost to like 20psi, and start stepping up your timing one degree at a time until you see knock. When you see knock, back it down by one degree, then start upping your boost one psi at a time. When you see knock, then step it down one psi.

You'll probably end up around 21-23psi (on 91 octane) with around 12-16 degrees of timing, which should net more power (and more safely) than running 30psi at 7 degrees.

Also, it's not about reaching the max limit of the turbo, its about reaching the max limit of your setup. Don't get caught up on the psi value. Much better to have your setup making more power and generating less heat at 21psi than to have it spinning it's balls off at 30psi, generating excess heat and pressure in your system, and making less power.

 

[boost97gst]

Im running 25psi on mine, a bit more timing, and also exactly 52lbs/min. My turbo is a tad bigger than an hx35 i believe. 25 is about my limit on 93. Im still picking up a little over 1* knock in 3rd gear during these pulls and the ambient temp has to be less than 65* for all this to work. Now, when the temps come down further i think i could flow a couple more lbs safely but not much more. Im going water/meth soon so it wont matter, my manifold will be the restricting factor!
The size of the turbo and manifold style will also be a guide to how much you can flow on pump. A bigger turbo=less knock. Thats the way it works. Theres a dyno challenge on here where guys have made over 650whp on straight 93 but theyre running massive turbos, strokers, 288 cams, SMIMs etc etc...

 

[phunny]

Had mine at 35psi and a max timing of 12 degrees on pump. Airflow was over 60lbs/min, zero knock.

 

[crash89]

Earlier this spring I was trying to dial the spyder in and was seeing 40 lb/min at 20psi on my HX35 and 13* of timing.

Phunny that is some awesome shit!!!

 

[boost97gst]

Had mine at 35psi and a max timing of 12 degrees on pump. Airflow was over 60lbs/min, zero knock.

damn dude. I have to say though, an hx35 isnt quite the turbo that a red is. Thats a bad ass snail. Also, may i ask what the temps where when you were doing these pulls? Im also curious as to the limit of an hx35-sized turbo on pump.
I also notice you have an extra .3L which may help it too.
Or maybe youre just damn good at tuning . Im a bit of a noob still to spark timing, got everything else down pat. I need to learn how to set my spool up timing better and peak timing i think. Its not been my main focus, im sure im missing out on some more power because of this. Im on evo8mod1 table just like the OP.

 

[phunny]

It was Dacogod on here that was tuning I was just driving . Temps were 75-80 outside. During tuning we ended up going near an E85 station and swapped over right after she was dialed in on pump.

 

[boost97gst]

niiiiiice, i see you went corn fed from profile too. Killer numbers bro. Thats a ton of whp on a red even, gotta love the e85. I hope they keep it around, ill probably be feeding my car with that stuff sooner or later too.

 

[bastarddsm]

Had mine at 35psi and a max timing of 12 degrees on pump. Airflow was over 60lbs/min, zero knock.

those numbers seem about right. Probably right under 500whp like that.

How do you "know" if you have reached the max boost of turbo on pump gas. Ive been messing around with boost level on my hx35 and at around 30psi logs are showing 52lb/min airflow but since im on the evo 8 stock timing maps it feels slow as its dropping into about 7* total timing with about 2* from 4000 to 5500 rpm, but if i add 1* timing from 4000 up i get 2 degrees of knock. So should i lower boost to like 24-5 psi so i can have 13* total timing.

Op you need a better intercooler and lower compression pistons, if you plan on making power on pump gas. you might also try a non projected plug. if your timing is lower than 5 at peak torque and much less than 15 at peak, then you might need to back to boost of

Had mine at 35psi and a max timing of 12 degrees on pump. Airflow was over 60lbs/min, zero knock.

those numbers seem about right. Probably right under 500whp like that.

How do you "know" if you have reached the max boost of turbo on pump gas. Ive been messing around with boost level on my hx35 and at around 30psi logs are showing 52lb/min airflow but since im on the evo 8 stock timing maps it feels slow as its dropping into about 7* total timing with about 2* from 4000 to 5500 rpm, but if i add 1* timing from 4000 up i get 2 degrees of knock. So should i lower boost to like 24-5 psi so i can have 13* total timing.

Op you need a better intercooler and lower compression pistons, if you plan on making power on pump gas. you might also try a non projected plug. if your timing is lower than 5 at peak torque and much less than 15 at peak, then you need to back to boost off.

I've read that timing less than 20 is bad and can burn valves, but I don't know that I believe that. I have seen several high power set ups with negative timing numbers.

 

[YZFR1]

I'd lower your boost to like 20psi, and start stepping up your timing one degree at a time until you see knock. When you see knock, back it down by one degree, then start upping your boost one psi at a time. When you see knock, then step it down one psi.

I even see some "reputable" forum members advising to do the same thing. That is exactly how NOT to do it. Unless being over advanced is the name of the game, of course.

If you had a choice between being at peak power, being underadvanced or being overadvanced, which would you pick? Of course, peak power would be the no.1 choice but without some sort of measuring device is hard to attain. Then it comes down to being overadvanced or underadvanced. Anywhere between the two you will be making similar power, however, one of these choices guarantees a shorter and harder engine life than the other. You make the decision which one

 

[T is for TURBO]

I even see some "reputable" forum members advising to do the same thing. That is exactly how NOT to do it. Unless being over advanced is the name of the game, of course.

If you had a choice between being at peak power, being underadvanced or being overadvanced, which would you pick? Of course, peak power would be the no.1 choice but without some sort of measuring device is hard to attain. Then it comes down to being overadvanced or underadvanced. Anywhere between the two you will be making similar power, however, one of these choices guarantees a shorter and harder engine life than the other. You make the decision which one

Huh?

Elaborate please? What parameters do you tune for?

 

[Archer Fabrications]

Also, it's not about reaching the max limit of the turbo, its about reaching the max limit of your setup. Don't get caught up on the psi value. Much better to have your setup making more power and generating less heat at 21psi than to have it spinning it's balls off at 30psi, generating excess heat and pressure in your system, and making less power.

You must not know much about Holsets. They wake up at 30psi and plenty running that with pump. OP can i see a log of your timing map? i think a curve like your explaining would work well on my setup with a 9.2:1 compression i gotta run lower timing then the other 2g guys.

 

[T is for TURBO]

You must not know much about Holsets. They wake up at 30psi and plenty running that with pump. OP can i see a log of your timing map? i think a curve like your explaining would work well on my setup with a 9.2:1 compression i gotta run lower timing then the other 2g guys.

I don't think you understood what he was saying. Turbo xxx may "wake up" at 30 psi, but, PSI means nothing. It's about IAT and air flow. If you can't keep your intake temps down, at 30psi, you likely won't make much power as you might at 27psi. Tune for your setup as a whole, not just your turbo's potential.

 

[Archer Fabrications]

I don't think you understood what he was saying. Turbo xxx may "wake up" at 30 psi, but, PSI means nothing. It's about IAT and air flow. If you can't keep your intake temps down, at 30psi, you likely won't make much power as you might at 27psi. Tune for your setup as a whole, not just your turbo's potential.

i have an HX40 and flow more air. others have flowed more air with the HX35 then he is pushing. like i said its been done. Just like any other setup you need the supporting mods to get there. obviously if OP chose an ebay FMIC he might have really bad heat soak that would contribute to knock. i was assuming he had the supporting mods layed out. he can definitely push more then what hes pushing on pump gas.

 

[boost97gst]

You need quite a setup to do 30psi on straight 93 on an hx35. Its all about IATs. And ambient temps help control those. OP wait til winter and crank it up to 30psi, i bet you can do it with ambients around 30*. Or, go water/meth and you can do 30psi all summer long

 

[Archer Fabrications]

You need quite a setup to do 30psi on straight 93 on an hx35. Its all about IATs. And ambient temps help control those. OP wait til winter and crank it up to 30psi, i bet you can do it with ambients around 30*. Or, go water/meth and you can do 30psi all summer long

true that. i've also been considering methinol but its just such a hassle to keep track of and fill heh. its on the list if i ever wanna hit my 9.99 goal we all would love 10 second pump gas cars. im limited by 92 in washington but soon ill be in an area with 94 in ontario canada

 

[phunny]

true that. i've also been considering methinol but its just such a hassle to keep track of and fill heh. its on the list if i ever wanna hit my 9.99 goal we all would love 10 second pump gas cars. im limited by 92 in washington but soon ill be in an area with 94 in ontario canada

Screw 92 or 94, from what I understand there is E85 all over around there?

 

[Archer Fabrications]

Screw 92 or 94, from what I understand there is E85 all over around there?

there are two E85 stations listed in ontario... and all the ones around me in washington are either at a military base, or so far it wouldent be worth it in my DD. if i had E85 nearby i would def do that i think that goes for most people

 

[phunny]

there are two E85 stations listed in ontario... and all the ones around me in washington are either at a military base, or so far it wouldent be worth it in my DD. if i had E85 nearby i would def do that i think that goes for most people

Ah, I see. Probably better anyway, it's addicting. I know when it goes away and I go back to pump I will have lost a little bit of myself :*(.

 

[Boostdriven]

I ran a 6 blade hx40 at 35 psi on pump gas with 2 550cc water/meth nozzles getting 19 degrees of timing by red line with zero knock. My friend runs hx52 at 43 psi on pump gas with 2 550cc nozzles getting 14-15 degrees of timing by red line.

I have an aem progressive water/meth kit, the tank is mounted where the stock intercooler was and the pump is where the stock air box was. The tank has a fluid level sensor so when its low it blinks the warning light. Had this kit for years and it works great.

 

[95ttalontsi]

Op you need a better intercooler and lower compression pistons, if you plan on making power on pump gas. you might also try a non projected plug. if your timing is lower than 5 at peak torque and much less than 15 at peak, then you need to back to boost off.

I have the vrsf intercooler with my whole bumper cut open so every square inch is exposed to incoming air. Im also running 2g stock pistons on 1g rods so compression should be 8.5:1. On a compression test i get 178 on every cylinder. I just dont understand why i get knock with good afr and low timing. Ive verified base timing and boost leak tested to 35psi. I think my ambiant temps are high due to airfilter in engine baywith no shield. It gets hot in there and I have shields on turbo and mani.

 

[boost97gst]

Ill have to review my logs and see what timing was, im fighting knock all the time too. Same compression and near brand new engine. The vrsf kit is very good and shouldnt be a hinderance, i mean its no ETS but youre just fine with it.
Under hood temps will always be high even with oem shields. If i idle even on a 65* night lately the intake temps(being read off the MAF mind you, not true IAT's) will climb past 100 pretty quick. But when im rolling they get within 15* of ambient. With some duct work we would both benefit. Just a scoop to force cold air up into the intake would make a world of difference.

 

[95ttalontsi]

Lowered boost to 22-23lbs and still cant get more than 10* timing without knock. And base timing is at 4* so its even 1* less than log. Also just installed brand new mitsu knocksensor at 7ft/lbs. Here a log from 10 min.ago

 

[My1GLaser]

Your 70-90mph time is still about the same as in your other thread.

Have you tried shooting for 10.4-10.5:1 AFR to cool it down in the CC a little?

Did you try the BR7ES plugs?

Where do you get your gas? Have you tried a different station? A while back I had to switch from the BP station I normally got premium at since they added something called Invigorate and it would make my car knock. I actually had to pull a couple degrees of timing across the board. I think I switched to Exxon and it got better. I mix in 60% E-85 now so it doesn't really matter anymore...

I also only fill up at a station with different nozzles for each grade of gas. You never really know how much 87 octane is in the line before you get the 93 you paid for. I have no idea where it switches over but what if it's at the tank under ground and you get 20ft worth of 87 octane in a 1" hose before the 93 comes out??? Overly paranoid, I know

Did you install the cyl head yourself? Did the combustion chamber look smooth and have no sharp edges?

 

[bradselph]

I also only fill up at a station with different nozzles for each grade of gas. You never really know how much 87 octane is in the line before you get the 93 you paid for. I have no idea where it switches over but what if it's at the tank under ground and you get 20ft worth of 87 octane in a 1" hose before the 93 comes out??? Overly paranoid, I know

Thank god i'm not the only one who does this i refuse to fill up at any station unless it has multiple hoses for each grade and so far i found 2 within a 50 mile radius.