I have a really good three core intercooler. How much boost should I be able to use on pump gas?
I have a really good three core intercooler. How much boost should I be able to use on pump gas?
[SIGPIC][/SIGPIC][FONT=Comic Sans MS]'91 Shadow convertible 2.5 auto, three core RP IC, S60/.48 stg 1, ported two-piece intake/52mm TB, Menegon +1 swirl, 88 turbo cam, Venolias, Crower rods, TU deep sump pan, ported exhaust, 3" from SV to TP, Hughes TC, Peloquin diff, DSS L5 driveshafts, Shelgame cal, Koni struts/shocks. [/FONT]
questions like this can not really be answered.Originally Posted by John B
it all depends on the calibration and the timing curve
you can run 30+ psi on pump gas if you want. but are you going to have the timing curve to really show off some power? doubt it.
I don't question that you're correct, but could you give any further guidance on how to get the best street performance on pump gas?
[SIGPIC][/SIGPIC][FONT=Comic Sans MS]'91 Shadow convertible 2.5 auto, three core RP IC, S60/.48 stg 1, ported two-piece intake/52mm TB, Menegon +1 swirl, 88 turbo cam, Venolias, Crower rods, TU deep sump pan, ported exhaust, 3" from SV to TP, Hughes TC, Peloquin diff, DSS L5 driveshafts, Shelgame cal, Koni struts/shocks. [/FONT]
Your sig is a great start to it. Now you just have to tune carefully to get it done. The big valve head, two piece, and IC will help you make a lot of power with a lot less boost.
You need a scanner or some way to watch knock while turning the boost up. I assume you already have a wideband. Once you see any knock counts either modify the tune or at least back down the base timing a bit. Depending on what boost level that's at you'd probably want to take even more out at higher boost just so that you never see knock at all in the high-boost regions.
If you have a cal that has aggressive timing in the first place and only modify your base timing you can have too much timing in some spots and not enough in others so being able to modify your cal is the ideal scenario here.
Dont push the red button.You hear me?
I'm running 17psi right now, hope to be running 20 by the end of the year. I have a fairly stockish setup though.
what do you consider pump gas? around here, 91 is the max (not 93), except one station that sells 100 octane "race" gas from the pump, but its pretty crappy...
also, what head (swirl or g), with what pistons (forged, cast, and standard dish?)
i get e-85 out of the pump, so is that pump gas? ive ran small bursts of 16psi in an all stock 87 SC with log mani and no intercooler, id run it higher because i havent heard knock yet, but id like to have more control with a 3 bar and a cal first...
and are you still running the stock garret?
I detonated badly and blew chunks out of a headgasket on 16psi on a log while having boost control issues. It's not something i would expect to work all the time (like in bad conditions).
Dont push the red button.You hear me?
Buy a progressive alky kit. I don't plan to ever buy race gas. Here we have 94 octane.
later Dick Westerhof
my cal was tuned up to 25 psi for 94 octane.
I wish I could give you a better information. maybe someone who has been doing their own tuning for awhile, can chime in?? im sure there is an approximate amount of timing that can be added in degrees, to each additional octane point.
---------- Post added at 10:17 PM ---------- Previous post was at 10:17 PM ----------
check his sig. the car is decked right out!!!
i think 20psi is agood number for 93octane gas, can you run more? yes but, you wont be able to put that power down with your mods. if you want to spin tire and look fast then go ahead lol. I just made a street/pump tune for my car and it goes to 23psi but, i cant get traction now until 4th! I'm sure if i go to 23psi 4th will be useless too. I say 20 and under for pump
Carroll
SILVER, 85 GLH-R/T, TIII powered, Fueltech, ID1300's. PTE5857
RED, 91 Spirit R/T - Holset HE351 - 12.6 @ 107...R.I.P.
Very wise indeed.
I'm blind, I was checking out the wrong sig... and wow, I'm jealous...
And vigo, I would never advise someone to run that much boost with a log intake on pump gas, unless that fuel was e-85that's why I asked what he considered pump gas, because there could be a pretty big difference there. I was with my friend when we turned 3 pistons into ash trays on his 85 block and pistons with a swirl head (g-head Cal) at only 10 psi on 91 octane.
Shouldn't the three-core cooler allow a bit more boost, all else being equal?
[SIGPIC][/SIGPIC][FONT=Comic Sans MS]'91 Shadow convertible 2.5 auto, three core RP IC, S60/.48 stg 1, ported two-piece intake/52mm TB, Menegon +1 swirl, 88 turbo cam, Venolias, Crower rods, TU deep sump pan, ported exhaust, 3" from SV to TP, Hughes TC, Peloquin diff, DSS L5 driveshafts, Shelgame cal, Koni struts/shocks. [/FONT]
3 core vs. what? Huge difference between that and a stock IC. Not as much with other ICs relatively speaking. A 3 core is a killer IC though.
Gary D made it for me using Saab 900 Blackstone cores. They used silver alloyed in with the aluminum to maximize heat transfer. Gus did a flow test of one of the cores and was really surprised at how well it flowed compared to other coolers he'd tested. He passed before he could post the results on his site.
[SIGPIC][/SIGPIC][FONT=Comic Sans MS]'91 Shadow convertible 2.5 auto, three core RP IC, S60/.48 stg 1, ported two-piece intake/52mm TB, Menegon +1 swirl, 88 turbo cam, Venolias, Crower rods, TU deep sump pan, ported exhaust, 3" from SV to TP, Hughes TC, Peloquin diff, DSS L5 driveshafts, Shelgame cal, Koni struts/shocks. [/FONT]
Get a cal with a knock indicator. My cal flashes the check engine light when knock is detected.
Mike Marra
1986 Plymouth Horizon GLMF "The Contraption" < entertaining sponsorship offers
Project Log:
http://www.turbo-mopar.com/forums/showthread.php?69708-The-Contraption-2013-14&highlight=
I have one, but the light stays on after any knock and I have to turn the engine off to reset it.
[SIGPIC][/SIGPIC][FONT=Comic Sans MS]'91 Shadow convertible 2.5 auto, three core RP IC, S60/.48 stg 1, ported two-piece intake/52mm TB, Menegon +1 swirl, 88 turbo cam, Venolias, Crower rods, TU deep sump pan, ported exhaust, 3" from SV to TP, Hughes TC, Peloquin diff, DSS L5 driveshafts, Shelgame cal, Koni struts/shocks. [/FONT]
Your looking for max boost on pump gas Id think your 1st investment should be forged pistons. You WILL see knock sooner or later, and at 20psi how long with that piston live, and how many times will it take it, once, twice,...?? Just be careful is no plan IMO. Your sig doesnt say if your running forged, but I assume you are with all those mods..I think boost geek nailed it, alky it....and run lots of boost!!
even with the best intercooler and the Venolias, no reason to push your luck (why chance it?). I wouldn't recommend more than 20 psi without datalogging, even around 20 you're flying blind on the edge of what is sensible for pump gas. takes very little to make ash trays with that kind of boost.
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