CobraRed_96_GT
Active Member
How would midlengths mate up with your mid-pipe? They require their own mid-pipe. And a midlength is just as hard to install as a LT.
STG 1 CAMS 101
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CobraRed_96_GT
Active Member
How would they? Think about how short the stock exhaust manifold is (or a shortie header) that's where your o/r X ends. The Bassani Midlength is between a LT and a shortie - where would it connect to the stock size o/r x? lolI thought they hooked up to the offroad x. Am I wrong?
The offroad x is a 5 piece design. if you remove the 2 most forward position pieces the headers should replace the pieces removed. That was my understanding of it.
Silly to even mention a new DD or gas mileage concerns. I drive 75 miles one way to work and never had any concerns whatsoever. I installed my cams at 125k miles. Even with gears I get 24MPG on the highway at 65MPH.
I have Comp 262's in my car and it is a nice bump in power. Good road manners and rough idle is not an issue. I gained enough to grab 4 tenths and 6MPH at the track in the 1/4. You will need a tune to get the full effects.
CobraRed_96_GT
Active Member
It wont mate up right or be the right length. Unless you fabricate it to your mid-pipe you'll need Bassani's mid-pipe.
CobraRed_96_GT
Active Member
Yes...pretty straight forward install. If you are semi handy you can do the swap. I wouldn't suggest getting a shop to do it since the cost would outweigh the HP gain. Are you planning on doing it yourself?
What are your long term future plans for the car? Head Swap( P&P Heads), SuperCharger, TurboCharger, Nitrous or stay N/A? I ask because you probably only want to do this once...
My suggestion is to look at the heads you are using head flow. Not so much the numbers but the Intake to Exhaust Flow Ratio( ITEFR ). Try to get as many lift points as you can and average that out for your heads ITEFR. I could tell you right now that for stock PI Heads it is roughly 85%.
A good N/A head should have an ITEFR between 70% and 80%. If the ITEFR is below 70%, you want a Cam that favours the exhaust to adapt for the weak exhaust flow. If the ITEFR is in that range you want a cam that does not favour either the exhaust or the intake. If the ITEFR is above 80%, you want a cam that favours the intake side to adapt for the weak intake flow.
Knowing that stock PI heads have a high ITEFR and CMS/VT cams favour the exhaust side is why I don't like any of VT N/A cam specs. Comp and Crower have cams that show no favouritism or very little to the exhaust side. These would be better choices. However, have you looked at HiTech Cams. Their N/A cams favour the intake side and considering that PI heads have a high ITEFR, those would be the cams to go with. That is just my $0.02
My suggestion is to look at the heads you are using head flow. Not so much the numbers but the Intake to Exhaust Flow Ratio( ITEFR ). Try to get as many lift points as you can and average that out for your heads ITEFR. I could tell you right now that for stock PI Heads it is roughly 85%.
A good N/A head should have an ITEFR between 70% and 80%. If the ITEFR is below 70%, you want a Cam that favours the exhaust to adapt for the weak exhaust flow. If the ITEFR is in that range you want a cam that does not favour either the exhaust or the intake. If the ITEFR is above 80%, you want a cam that favours the intake side to adapt for the weak intake flow.
Knowing that stock PI heads have a high ITEFR and CMS/VT cams favour the exhaust side is why I don't like any of VT N/A cam specs. Comp and Crower have cams that show no favouritism or very little to the exhaust side. These would be better choices. However, have you looked at HiTech Cams. Their N/A cams favour the intake side and considering that PI heads have a high ITEFR, those would be the cams to go with. That is just my $0.02
CobraRed_96_GT
Active Member
That doesn't make much sense, even ported PI heads will favor the intake. Most all heads favor the intake (hence the bigger intake valve). I think in relativity PI heads are pretty balanced and you can chose a cam that favors either with different but good results. And based on the VT lift schedule I don't see the exhuast overlap being favored much more than other cams - are you talking lobe separation and variation?
And you can't measure flow velocity just based on CFM, plus the exhaust gases are being pushed out not drawn out which adds a different dynamic to the flow ratio I would think.
And you can't measure flow velocity just based on CFM, plus the exhaust gases are being pushed out not drawn out which adds a different dynamic to the flow ratio I would think.
Ok im gonna have to read those replies a couple more time to wrap my head around them. My long term goals for the car are to stay with a fairly stock motor with a pro-charger down the road. Nothing radical on boost keeping everything very streetable and safe. Maybe around 9 psi of boost and very well intercooled. Wouldnt it be cool if my inconspicuous little GT wasted a stock SRT8 Challenger in full street trim?
I want to install these cams myself. For those who have done this install, do I need the ford special tools to remove the cam followers or will they come out and reinstall on the new cams? Also how difficult is it to restring those chains? I understand that the chains have off colored links to indicate their positions on the crank and cam timing marks.
I want to install these cams myself. For those who have done this install, do I need the ford special tools to remove the cam followers or will they come out and reinstall on the new cams? Also how difficult is it to restring those chains? I understand that the chains have off colored links to indicate their positions on the crank and cam timing marks.
CobraRed_96_GT
Active Member
Buy some blower cams if your going to go FI down the line FOR SURE. You'll pick up NA power for now and it'll help a lot with you put on the supercharger. You only need the Ford cam tool if you're replacing springs - not if you don't.
Nothing is for certain but the here and now. Im aware of the blower cams being out there but it seems like a mild N/A cam now would be cool. At rate of mileage im producing, by the time I get a blower I may be building a motor to suit it anyway. I wouldnt risk boosting a 1xx,xxx mile motor.
I used a tool to hold the chains in place without removing them. It helps to have a buddy for an assist. The cam followers are not an issue for removal. In fact they fall right into the head if you are not careful. It's almost like trying to put a puzzle together holding it off the ground. Trying to bolt the cam down without losing your rocker requires and extra hand.
You are missing the point completely. The intake side of the heads should outflow the exhaust, the question is how much does it outflow the exhaust. That is what you want to look at. Stock PI heads exhaust flows on average 85% to what the intake flows. For a good N/A head that is too high, so you want a cam that has more lift and duration on the intake side compared to the exhaust side to compensate for the lack of intake flow on the heads.
Ideally if you are looking at staying N/A you want a head where the exhaust flows between 70% and 80% of what the intake flows.
P&P PI heads actually take the ITEFR higher, some the exhaust is flowing over 90% compared to the intake side. That head is really only good for a power adder.
Have you ever wondered why generic Comp Cams work as well and in most cases better N/A than VT N/A Spec'd cams? Ever wonder why most of the fastest N/A 2V do not run VT cams? The reason that VT are even close is because Comps have a loose LSA( 114 ) compared to VT's tight LSA( 110 Stg 1 N/A ). IMO, a good N/A cam should have an LSA of 111. There is people having lots of success with Comp Cams N/A that have been ground with a LSA of 111.
CobraRed_96_GT
Active Member
I know intake outflowing is normal, my argument is the PI head doesn't favor either too heavily - like the quote says. 165vs150 cfm stock is not disproportionate to most heads - unless you're talking about other flow measurments than CFM which would make sense. And where do you see CompCams working better in "most cases"? I'd like to see that, and what your definition of "better" is.
An old article I read said that the comps cams performed well because of high ramp speeds. The valves opening and closing at a faster pace.
CFM is what the measurement should be. You don't want heads that flow nearly the same intake as they do exhaust in a N/A setup. 165 CFM Intake should be 116 to 132 CFM Exhaust for it to have a good N/A head flow ratio.
When I had my N/A engine built, I talked to everybody on the top 10 PI N/A 2V cars at Modular Depot. At that time, there was 2 using VT Stg 2 Cams, one using VT Stg 1 Cams, the other 7 were using Comp cams including the fastest 3. I talked to the top 5 on the NPI N/A 2V. 4 were using Comp cams, the other was using Custom Crowers. Of the 15, 3 were using VT, 11 were using Comp and 1 using Custom Crowers.
I talked to just about every major Modular Engine builder as well. Those that were willing to talk N/A setups almost all thought that the best N/A cams were ones that had the same duration and lift for intake and exhaust with a LSA of 110 - 112. If you really wanted to push the limits, a LSA of 108. The reason they gave was that the 2V head specifically the PI head( as most did not think highly of NPI or SVO heads ) flow characteristics are better suited to a being a Power Adder head. Their reasoning was exactly as you pointed out, the heads intake/exhaust flow is proportionate. Some of them said that if I was going to stay N/A that they would work the heads on the intake side only and leave the exhaust side stock to make for a better N/A head. They found this to work better N/A than porting both the intake and exhaust side for N/A combos.
As for the VT/Comp cams debate. That has been beat to death in countless threads and I sure as hell don't feel like going and finding them now. What I do remember is that guys that had Comp 262s compared to VT Stg 1 N/A cams with identical mods usually made 8 RWHP more with the Comps. Now if you want to look there is a recent thread on Modular Depot where a person just swapped out his VT Stg 2 N/A cams for Comp 270s. The reason is he wants the blower friendly LSA of the Comps. He still doesn't have a blower on his car and his car has suffered no power loss or running slower in the 1/4 which is something you would expect for both going from a supposedly properly Spec'd N/A cam to a generic cam. Because it did not happen, I would suspect that those N/A spec'd cams are not properly spec'd at all.
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