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**Shane@DBPerformance** · 06-01-2008

I almost always run into knock with a 16G or bigger on a stock SMIC if we try to run much boost. 12-14psi usually works okay, but thats no fun. A bigger turbo will heatsoak an intercooler faster, because it flows more air, even though it might put out colder air at the same boost level. 550+cfms at 200 degrees is going to kill the intercooler faster than 405cfms at 205 degrees. A 14B is usually fine up to around 17psi on the stock SMIC on pump gas. On E85 or race gas, it all goes out the window. E85 cools like crazy and acts like you put an air-to-water intercooler on the car with an endless supply of ice. Drag cars that run straight E98 or methanol don't even need to use intercoolers at very high boost. Race gas can be very high octane and octane will greatly reduce the chance of knock from high intake temps. My wife ran 25+psi with 110 octane on the stock 14B with the stock SMIC with no fuel control and went 12s.

A Walbro 255 will usually overrun a stock FPR, but it usually isn't any problem at all to tune around it. I have never had a problem tuning a car with a Walbro 255 and stock FPR with SAFC, DSMLink or an AEM EMS. With 2 fuel pumps it will get too out of control. I run 1600s and a stock FPR on my 1G with EPROM tuning. An adjustable is definately nice and might make things easier to tune, but if you are on a budget at all, it is something that I would skip. With a true speed density setup like an AEM EMS or the way the stock Honda ECU work, then FPR overrun is pretty much a non issue as long as you base + boost isn't too high. I tune Hondas with FPR overrun all the time on Hondata/Crome/Neptune that have their base fuel pressure in the 50-60psi range and it is perfectly fine because of the way their stock ECU works.

It seems like a few year ago someone decided that a DSM couldn't run or tune halfway decent without an aftermarket AFPR. Even though for years before that we didn't have any problems. A lot of people on here know that I am one for running the correct parts and doing things right, but too often I see a fancy AFPR setup on a car that totally missed some other important part that actually makes a difference. A fuel pressure gauge though is one of the most useful gauges for tuning on the dyno though when things are acting wierd.

Bertrenolds5: What MAS do you have? The stock 14B will max out that stock MAS and make anything else you do as far as tuning worthless.

06-01-2008	#24
Shane@DBPerformance formerly ecoli Join Date: Oct 2003 Location: On the dyno Posts: 4,892	Re: SMIC with big16g? I almost always run into knock with a 16G or bigger on a stock SMIC if we try to run much boost. 12-14psi usually works okay, but thats no fun. A bigger turbo will heatsoak an intercooler faster, because it flows more air, even though it might put out colder air at the same boost level. 550+cfms at 200 degrees is going to kill the intercooler faster than 405cfms at 205 degrees. A 14B is usually fine up to around 17psi on the stock SMIC on pump gas. On E85 or race gas, it all goes out the window. E85 cools like crazy and acts like you put an air-to-water intercooler on the car with an endless supply of ice. Drag cars that run straight E98 or methanol don't even need to use intercoolers at very high boost. Race gas can be very high octane and octane will greatly reduce the chance of knock from high intake temps. My wife ran 25+psi with 110 octane on the stock 14B with the stock SMIC with no fuel control and went 12s. A Walbro 255 will usually overrun a stock FPR, but it usually isn't any problem at all to tune around it. I have never had a problem tuning a car with a Walbro 255 and stock FPR with SAFC, DSMLink or an AEM EMS. With 2 fuel pumps it will get too out of control. I run 1600s and a stock FPR on my 1G with EPROM tuning. An adjustable is definately nice and might make things easier to tune, but if you are on a budget at all, it is something that I would skip. With a true speed density setup like an AEM EMS or the way the stock Honda ECU work, then FPR overrun is pretty much a non issue as long as you base + boost isn't too high. I tune Hondas with FPR overrun all the time on Hondata/Crome/Neptune that have their base fuel pressure in the 50-60psi range and it is perfectly fine because of the way their stock ECU works. It seems like a few year ago someone decided that a DSM couldn't run or tune halfway decent without an aftermarket AFPR. Even though for years before that we didn't have any problems. A lot of people on here know that I am one for running the correct parts and doing things right, but too often I see a fancy AFPR setup on a car that totally missed some other important part that actually makes a difference. A fuel pressure gauge though is one of the most useful gauges for tuning on the dyno though when things are acting wierd. Bertrenolds5: What MAS do you have? The stock 14B will max out that stock MAS and make anything else you do as far as tuning worthless. __________________ www.dbptuning.com Last edited by Shane@DBPerformance; 06-01-2008 at 07:58 PM..