how psi can safley handle

driftingmustang · Oct 2, 2007

how much PSI can a 4.6L gt engine safley handle.

mike97gt · Oct 2, 2007

theres a LOT of factors.
intercooler, size of turbo/supercharger, type of supercharger. theres more i jsut cant think of anymore off the top of my head.. haha

nesqwick_05 · Oct 2, 2007

quite a bit actually, ive seen as much as 15lbs on the stock motor with some tuning from a vortech. i would probably stay somewhere around 10-12lbs to get the most power outta the safe route...

Jrgunn5150 · Oct 3, 2007

Stick to 10 if you like your rods on the inside of your motor...

Johnny Langton · Oct 4, 2007

Safely....ZERO.
I've seen stock engine with the upper ring lands crushed by detonation,so it's all dependant on the tune,the fuel quality,and the guy behind the wheel.
JL

Fets · Oct 4, 2007

like 6-8lbs I'd say to be safe.

Shocker98GT · Oct 4, 2007

Something like an intercooled twin screw (Kenne Bell) or roots, 8 or 9 psi would be as high as I went on a stock motor, and that's IF you get a good, safe tune.

Intercooled centrifugal, 10psi is the absolute highest I'd take it

Non intercooled twin screw-6psi is as high as I'd go

non-intercooled centrifugal-8psi is the highest I'd go.

scarface · Oct 4, 2007

I ran 12 lbs, but a spot on tune is needed with any amount of boost.

ripper · Oct 4, 2007

Johnny Langton said:
Safely....ZERO.
I've seen stock engine with the upper ring lands crushed by detonation,so it's all dependant on the tune,the fuel quality,and the guy behind the wheel.
JL

+1 Dont even think of throwin a blower on and driving away. 6-8 lbs and a very good tune and you will have plenty of fun and get alot of miles out of it. 10-12 lbs more fun less miles LOL. 15+ you need a built motor for sure.

Johnny Langton · Oct 4, 2007

Just to calrify since I missed it in my original reply...
By stock-I mean N/A. No S/C, no n2o, nothing....bone stock engines with shattered ringlands.
JL

driftingmustang · Oct 4, 2007

what is a ring land?

Johnny Langton · Oct 4, 2007

driftingmustang said:
what is a ring land?

Ring lands are the portion of the piston that the rings are seated against(the outer edges of the ring grooves).
JL

98SILVERSTANG · Oct 5, 2007

I use to run 12psi boost with my stock shortblock and 10.5:1 compression with no issues at all. I would however use torco additive with 93 octane fuel and if I went to the track would run race fuel. I would probably stick with no more then 10psi to be safe.

Alain

1996mustangGT · Oct 5, 2007

Jrgunn5150 said:
Stick to 10 if you like your rods on the inside of your motor...

+1

Jrgunn5150 · Oct 5, 2007

98SILVERSTANG said:
I use to run 12psi boost with my stock shortblock and 10.5:1 compression with no issues at all. I would however use torco additive with 93 octane fuel and if I went to the track would run race fuel. I would probably stick with no more then 10psi to be safe.

Alain

So did I, lol, but i didn't expect it to last. I just used premium, no aditives.

nesqwick_05 · Oct 5, 2007

Kind of an odball here but I will say that a car doesn't need a tune to run on boost, the use of an fmu will work wonders on a near stock set up. Mine for example is 6lbs with the fmu, just make sure if you where to run an fmu that u have a good vaccum sorce. Otherwise get it tuned, or do it yourself. . .

Johnny Langton · Oct 6, 2007

nes said:
Kind of an odball here but I will say that a car doesn't need a tune to run on boost, the use of an fmu will work wonders on a near stock set up. Mine for example is 6lbs with the fmu, just make sure if you where to run an fmu that u have a good vaccum sorce. Otherwise get it tuned, or do it yourself. . .

There's more to a car's tune being right other than air/fuel. An FMU is a POS and a band-aid for using the right injector size.
JL

ripper · Oct 6, 2007

Thats true John but with 6lbs of boost I think an FMU for a guy on a budget (most of these young guys are in school) is a safe bet. You wont see the hp that a custom tune will give you but imo it will be ok if you keep the boost down. A custom tune takes in so many other variables other than a/f. I could be wrong though im not a mechanic or a tuner just going by what ive read on forums and what my tuner has told me. Most of these guys are going to school and working minimum wage jobs at night to pay for their mods. When you start getting into injectors, pumps, tune, dyno time, and everything else it adds up.

VertTireSmoke · Oct 6, 2007

Stevo said:
Thats true John but with 6lbs of boost I think an FMU for a guy on a budget (most of these young guys are in school) is a safe bet. You wont see the hp that a custom tune will give you but imo it will be ok if you keep the boost down. A custom tune takes in so many other variables other than a/f. I could be wrong though im not a mechanic or a tuner just going by what ive read on forums and what my tuner has told me. Most of these guys are going to school and working minimum wage jobs at night to pay for their mods. When you start getting into injectors, pumps, tune, dyno time, and everything else it adds up.

True that most are on a budget (myself def included) but if u are spending the money on forced induction u are better off getting it tuned IMO. Getting a tune would be a hell of a lot cheaper than replacing a blown motor if something went wrong.

Jrgunn5150 · Oct 6, 2007

This is why I didn't say anything about an FMU... People used them for years, no they are not ideal, but sometimes you just don't have that extra 1k laying in the couch cushions for the correct injectors and a custom dyno tune.