Fairmont 2.0 (forged lq4, s480, 800whp, under new management)
04-01-2013, 03:40 PM
#1981
I did go look at the car but you weren't there, talked to someone and they told me you just walked away. I am building a 5.3/S475 turbo setup for my car and I will start running at SCR and No Problem so next time I see your car at the track, I'll be sure to introduce myself. Clint
Mike
04-01-2013, 05:28 PM
#1984
It's just one guy's opinion, but I don't understand wanting compression much above 8.8:1 or 9:1 when you're talking about a turbo engine... The compression lowers your detonation threshold significantly, and only does a tiny bit for power or spool. Much better in my mind to go with lower compression to raise detonation threshold so you can safely add more boost and make a lot more power.... After all, det is what's taking out the pistons.
Put in those forged Wisecos with lower compression and you can make some crazy power to really give those rods a strength test!
Put in those forged Wisecos with lower compression and you can make some crazy power to really give those rods a strength test!
I used to be of the low compression mind set, but recently methanol injection by the gallons with 93 pump gas has changed my mind quite a bit along with E85 itself in those set-ups.
04-01-2013, 06:57 PM
#1985
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Compression is one thing I don't think people take enough advantage of. I think you'd be surprised how much faster a turbo car can spool, how much more power it can make and just how much better a high compression turbo engine runs.
I used to be of the low compression mind set, but recently methanol injection by the gallons with 93 pump gas has changed my mind quite a bit along with E85 itself in those set-ups.
I used to be of the low compression mind set, but recently methanol injection by the gallons with 93 pump gas has changed my mind quite a bit along with E85 itself in those set-ups.
I know that when I was doing ridiculous amounts of water/methanol injection it really did make crazy things seem possible.... I guess the difference was that I didn't really see a significant benefit from the extra compression. Hrmmmm?
04-02-2013, 09:29 AM
#1988
There are a ton of variables to this question. Combustion chamber design, amount of boost wanting to be utilized, valve angle(part of chamber design), intercooled(what type of intercooler), no intercooler, type of racing being done(1/4 mile, 1/8th mile/ roll racing etc.)
04-02-2013, 10:48 AM
#1989
I called Wiseco. I asked if by "drop in," they meant I could drop them in with my existing rotating assembly, or if I would be "dropping off" my $100 junkyard motor at the machine shop for a full balance.
What do you think the answer was? Pistons are meant to "drop in" with the use of the existing rods, after you drop a nice pile of cash with your local machinist to balance it all up.
The pistons weigh 442 grams each. Does anyone have any idea what the stock 5.3 or 4.8 pistons weigh? My motor has a Gen III crank, and Gen IV rods and pistons, which may be a mismatch themselves. I do believe the Gen III pistons were dished and the rods were certainly less beefy. Taking that into account, it really may work....since I can't imagine my current crap is balanced any longer.
Still, I calculate my compression at around 8.8 with the dished JYDs. That will leave room for boost, but I do like the way the car runs now with 10:1 compression. Flipside is that I do not want to pull this motor once a month to swap pistons. I am a lazy dude, I don't even want to do it once. LOL.
Mike
What do you think the answer was? Pistons are meant to "drop in" with the use of the existing rods, after you drop a nice pile of cash with your local machinist to balance it all up.
The pistons weigh 442 grams each. Does anyone have any idea what the stock 5.3 or 4.8 pistons weigh? My motor has a Gen III crank, and Gen IV rods and pistons, which may be a mismatch themselves. I do believe the Gen III pistons were dished and the rods were certainly less beefy. Taking that into account, it really may work....since I can't imagine my current crap is balanced any longer.
Still, I calculate my compression at around 8.8 with the dished JYDs. That will leave room for boost, but I do like the way the car runs now with 10:1 compression. Flipside is that I do not want to pull this motor once a month to swap pistons. I am a lazy dude, I don't even want to do it once. LOL.
Mike
04-02-2013, 02:59 PM
#1996
When you get the head shaved and block decked, make the machinist slow the cutter down and get a smooth surface so the gasket will seal and you will be fine with the cometic. Slow down the forward speed not the speed of the cutter doing the cutting
04-02-2013, 03:34 PM
#1997
Shave the head and see if you can zero deck the block with the new piston. It should bring you up in the mid 9 compression range.
When you get the head shaved and block decked, make the machinist slow the cutter down and get a smooth surface so the gasket will seal and you will be fine with the cometic. Slow down the forward speed not the speed of the cutter doing the cutting
When you get the head shaved and block decked, make the machinist slow the cutter down and get a smooth surface so the gasket will seal and you will be fine with the cometic. Slow down the forward speed not the speed of the cutter doing the cutting
Option 1: Replace broken piston with stock replacement;
Option 2: Replace all stock pistons with stock replacements;
Option 3: Replace all pistons with Wiseco JYDs in the driveway, with no balance job and no machine shop visit.
I am not getting heads milled, and blocks decked and spending a **** load of money on a $100 JY motor. I just want to put this thing back together.
Mike