853 heads??
853 heads?? What is the max power people have made on stock 853 casting heads??
My car made 470 rwhp and the dyno graph fell off at 5700 rpm every time and I'm thinking it may be the heads not flowing past that point.
My car made 470 rwhp and the dyno graph fell off at 5700 rpm every time and I'm thinking it may be the heads not flowing past that point.
Whats up Tyler,
Heard your car was being tuned yesterday, thats a good number for 7psi through an auto (what I heard they were tuning it at). I've got box stock 853s with crappy 918 springs on my heads currently thanks to the previous owner...no signs of valvefloat on mine, but it did peak at 5200 and slowly fall. What size turbo are you running? Mine is a T-70 with a P-trim exhaust wheel. The guys thought that mine was falling off due to the exhaust housing restricting flow in combination with my stock 853s and stock ls1 intake. But, then again I'm seeing 16psi on the torque peak and falling off to 13.5psi at peak hp - thanks to my crappy ebay gate I need to replace. So, in comparison, 5700 isn't too bad I wouldn't think. Do you have an ls6 intake on yours?
Heard your car was being tuned yesterday, thats a good number for 7psi through an auto (what I heard they were tuning it at). I've got box stock 853s with crappy 918 springs on my heads currently thanks to the previous owner...no signs of valvefloat on mine, but it did peak at 5200 and slowly fall. What size turbo are you running? Mine is a T-70 with a P-trim exhaust wheel. The guys thought that mine was falling off due to the exhaust housing restricting flow in combination with my stock 853s and stock ls1 intake. But, then again I'm seeing 16psi on the torque peak and falling off to 13.5psi at peak hp - thanks to my crappy ebay gate I need to replace. So, in comparison, 5700 isn't too bad I wouldn't think. Do you have an ls6 intake on yours?
Not much, yeah it's a front mount t76gts and at first he was thinking it was valve float but with the double springs in there that shouldn't be a problem until like 7000+ rpm so I started thinking maybe it was the heads. There is an ls6 intake on mine.
The 470 was pretty close to what I was expecting and I probably don't need to make much more than that considering I'm on stock bottom end.
Did Andrei tune your part throttle as well?? Mine is pretty rough under normal driving but clears up at wot.
The 470 was pretty close to what I was expecting and I probably don't need to make much more than that considering I'm on stock bottom end.
Did Andrei tune your part throttle as well?? Mine is pretty rough under normal driving but clears up at wot.
I am making 500 rwhp with mine. Stock bottom end, fast intake, with a cam and 921 springs. I am running around 6-7psi. This is on a stalled auto also. Mine peaked at 6500and would probably kept going but I didnt want to spin it any higher. I dont think the heads are your problem.
TECH Fanatic
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From: ocala,fl--- forest-ocklawaha
theres a guy on here from canada i think, he has stock heads with springs,on his forged bottom end 6.0, has a huge turbo i think its like a 91mm, he made 1100 to the wheels..
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Was the converter locked? My part throttle is fine, but I'd give Brett @ XP credit for that because he had already tuned that aspect of the car, Abel just went over the 3k+ part (WOT aspect). However, I do notice that below 3k it is a bit more rich than it was, but that may have been a tweak that Abel did to help the turbo spool a lil quicker maybe? Not sure.
Dynojet? I thought Abel had a Mustang Dyno? It looks pretty rich (11.0) and it looks like it goes to about 10.8-10.5 up top, I know it's a stock bottom end but it can probably take 11.5 at the tailpipe the whole run. There is some power to be had there. Graph is pretty wavy, but that is probably because of the STD and smoothing low, but still, quite wavy.
I'd see what they have to say.
I'd see what they have to say.
8 sec potential, 12 sec slip
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From: Savannah, GA
Why do the TQ and HP lines not cross at 5252 RPM??? 
**edit nevermind, just noticed that the scale is off on either side for the different numbers.
I have the stock 241 heads off my car I'd sell ya cheap if you want to try them out. Only 50k miles on em
**edit nevermind, just noticed that the scale is off on either side for the different numbers.
I have the stock 241 heads off my car I'd sell ya cheap if you want to try them out. Only 50k miles on em
