The Port and Polished PI headswap is almost done what kind of times you think I will run after this? Current best with mods in my sig is 14.4 @ 95. Also doing some DR's and 4.10's after this you think I will be seeing 12's with this setup?
P&P PIheadswap E.T.?
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Not without the PI intake upgrade as well as a higher flow upper manifold and T/B. Even then, I wouldn't think much more than mid/low-13's are going to be the norm with just that set up.
Even so, I still don't see you making any more than about 240-245rwhp. Gonna need more jam than that to crack the 12's.
Gearbanger 101 said:
So you think with a Port and Polished PI headswap meaning heads, cams, and intake I will only gain 30-35 rwhp????
billyfe390 said:
Well my car is the 248A package which is basically a stripped down GT so my car weights less than the average GT. I'm just wondering if with the P&P PI headswap, DR's and 4.10's if I will be able to make 12's.
You will have a lot more than 240-245 hp. Especially if your heads are P&P. I have a 98 gt with a PI head swap(unported) , intake, Ford racing shorty headers, off road H, ported upper plenum, 70mm tb, cold air,3.73's, 40 series mufflers, after market cams from comp cams. Mine dynoed at 276.8 hp/312rq untuned. With the stock cams it dynoed at 259 hp. If your setup is anywhere near mine then you can expect near the same and if the heads are ported then you'll have more. You will lose a little on the low end with the port job but you have great top end.
Sorry, I overlooked the fact that you've got a P&P done to your PI's, so lets put it this way.....a stock '99-up makes around 225-235rwhp. So, say another 15-20hp for the P&P and added compression and another 10-15 for the intake/exhaust mods and tune. Probably in the range of 260-270rwhp, but still doubtful you'll see 12's.Sick96Stang said:
I personally think the best you'll muster with just those bolt ons, D/R's and 4.10's is low-13's, but hey anything is possible.
You have to remember that you wont have the compression factor. It would have been about 10 to1 with the smaller combustion chambers. But if you have ported heads the ratio will drop. Because of the of the lower compression you have the option of supercharging your engine which you cant do with high compression
Going to PI heads on a ’96-’98 Modular engine usually brings compression to a minimum of 10.1:1. More often than not, the numbers hover right around 10.4:1. Porting doesn’t normally include altering the combustions chambers volume. It’s usually nothing more than enlarging and reshaping the intake an exhaust runners, while blending them into the port pockets around the valve guide. Some will clean the combustion chamber up a little around the area where the valve meets the seats, to improve low-lift flow and reduce shrouding. But as a rule, most places won’t alter the combustion chambers at all unless specified. I'd image this would be his case and as such, his CR would remain within the 10.1-10.4 range.Nredgt98 said:
Regardless, porting the chambers themselves has a less dramatic effect on volume that you may think. In doing so, only the swirl dams are removed to increase overall flow (reduce shrouding) and increase flame propaganda within the chamber itself. Although this does allow an increase in upper limits of flow, increasing horsepower, it has a negative effect on overall efficiency and effects low-end torque…not to mention fuel economy takes a nosedive. Regardless, even if he did have the swirl dams removed, the compression would drop by no more than a few cc’s at most. A guy on tccoa.com had his done and it still resulted in a near 10:1 ratio….which is still a full point higher than stock.
Gearbanger 101 said:
Its a friend of mine who is doing the P&P. I just want to make sure I am able to run boost. He is grinding out the swirl dams I know that much. Should I ask him to alter the combustion chambers or can I run boost on 10.1 - 10.4 CR?
So with the P&P PI heads and him grinding out the swirl dams is my MPG gonna take a nosedive?
My guess with the way my car reacted, and I had long tubes and a prochamber installed at the same time, is that you will pick up close to a second. I would think around mid to low 13's. I really don't think you'll hit 12's until you get cams.
TweekedGT said:
Hmmm I'm hoping to hit 13.5 after the P&P PI headswap then after the DR's and 4.10's I'm gonna try for 12's. If I can hit 13.5 I dont see why DR's and 4.10's wouldnt be able to shave off .5-.6.
In a word....yes. I wouldn't knock the swirl dams off if I were you. It's a real art to properly CC a set of combustion chambers and is best let to the hands of a skilled professional or a CNC machine. If you want to lower compression, the only way to do it is with the pistons. Yeah, you could knock it down a little by taking off the dams, but not enough for your purposes. Not to mention, the stock slugs suck anyway, so you may as well pony up the money and replace them to do it right. Besides, 10.1-10.4 isn't ideal for running boost, but not impossible. You'll have to be dead on with your tune, while generous with the fuel and conservative with the timing. You would however be better off filling the block with a set of 19cc pistons and beefed up rods. If not for drivability, then for longevity sake.Sick96Stang said:
I don't think you'll pick up 1.5 seconds with just those mods. That is an absolute pile of time. I could be wrong. I'm guessing 1-1.2 seconds with all of those mods. You'll just have to run her and tell us how you did. I'm curious to see how it goes.Sick96Stang said:
TweekedGT said:
Yea, the port and polishing and PI headswap should be all done by the end of January so I still got a month or so.
