Engine Newbie Deciding On A Cam

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Hey guys, so I have ordered my TFS heads and custom grind cam, and am choosing to take your advice and order the 75mm TB and Pro M MAF calibrated for the 24s. My question; will I need/benefit from the plenum that seems to be usually paired with the TB or is it unnecessary? Thanks in advance!
 
I'm not sure what you're asking here? What do you main "paired with"?

If you're asking if you should buy a plenum that has a matching 75mm inlet to accommodate your 75mm throttle body, then yes.

You're already got the Trick Flow heads, you'd benefit from their Track Heat intake as well at this point. Edelbrock RPM II, Holley Systemax II...both also good options and all will handily outflow your ported GT40....which to be frank hasn't got the surface area to take advantage of that 75mm throttle body and spacer.

What I'm saying is, that if you plan on keeping the GT40 intake, you might as well send back the 75mm throttle body and spacer and exchange them for a 65-70mm unit, as the bigger set up isn't going to make a difference.
 
Got it. What I meant was i often see the 75mm throttle body and plenum sold together as a package while I don't see that as much for the other sizes. You effectively answered my question for the most part, so thank you. I currently have a 70mm tb installed, but I was planning on adding some power so i suppose ill go ahead and order a higher flowing intake as well.
Now here's what I'm thinking; I haven't yet ordered the TB or MAF. Since i may as well pull the trigger on a new intake mani, Would it benefit me at all to go ahead and order 30 lb injectors and go with a Pro M 80mm maf and 80mm TB, and if so then what intake manifold would be ideal? How would that affect my head & cam choice/which heads would be most effective with that setup?
 
If you are already using a 70mm TB, just keep it. No point in spending money to goto a 75. Besides, most intakes won't take a 75 without some minor porting.

As for the 30's, depending on the intake you use (i like the rpmII), you will be close, but probably still in the 24 category.
 
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If you already have the MAF for 24's keep the injectors. If not I would go right to 30lb injectors and a matching MAF- gives you more room to grow and you can dial in the fuel pressure with the injectors or get a tune. For the TB, 70mm is plenty big for your application. You won't see any difference in the 75mm. If you want, take the TB gasket and lay it over the inlet on the intake and then use a marker to outline the diffference. Then you can use a dremel to open it up. If you already have the explorer or gt40 intake, send the lower to Tom Moss and let him port it and it will outflow pretty much every stock aftermarket intake.
 
If you already have the explorer or gt40 intake, send the lower to Tom Moss and let him port it and it will outflow pretty much every stock aftermarket intake.
I normally agree with a lot of your viewpoints, but in this case I'm sorry Mike, but not on it's best day would even the heaviest modified Tmoss ported lower intake come close to hanging with the current crop of aftermarket offerings.....never mind out flowing them.

With port size and runner volume alone, my STOCK Trick Flow lower outright puts a GT40 (ported, of otherwise) to shame.
 
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Gt40 style intakes, be it cobra, gt40, explorer, regardless of the work, could never keep up with the best intakes out there.
If you are forcing air through them, they are good, but if not the more modern intakes, kill them.

My buddy even used to use extrude honed cobra's back in the day (that was like a $400 intake with $500 worth of work). Made great power, but when most of the newest intakes came out, financially it became a loss, just easier and cheaper to plain old buy a better intake.
 
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I normally agree with a lot of your viewpoints, but in this case I'm sorry Mike, but not on it's best day would even the heaviest modified Tmoss ported lower intake come close to hanging with the current crop of aftermarket offerings.....never mind out flowing them.

With port size and runner volume alone, my STOCK Trick Flow lower outright puts a GT40 (ported, of otherwise) to shame.


Then I stand corrected. Shows you the last time I was shopping for an intake was during the Clinton administration. lol Carry on
 
I have the GT40 tubular off the old 351 lightning trucks. I love the way it looks and am a little torn. But at the end of the day I'm in it for power, not aesthetics. So I suppose a new RPM2 or Systemax 2 is the way to go.
 
Then I stand corrected. Shows you the last time I was shopping for an intake was during the Clinton administration. lol Carry on

Ahhh, but those were some good times though, weren't they. :D

I have the GT40 tubular off the old 351 lightning trucks. I love the way it looks and am a little torn. But at the end of the day I'm in it for power, not aesthetics. So I suppose a new RPM2 or Systemax 2 is the way to go.

In that case, the decision is made for you. The Lightning had a 351W....in which case you couldn't use the intake, even if you wanted to as the lower won't fit a 302.
 
Ok meaning i must have only the upper, and I may as well get the Holley unit. Didnt know that, I haven't even pulled it off before. Thanks for the help guys, and thanks for being sensitive to my lack of knowledge, you guys are a knowledgeable and helpful group!
 
Just thought I'd update. I have ordered the 75 mm Pro M MAF, and have acquired a set of TFS 170 heads. I've decided on a Lunati Voodoo cam (part 20350711) at the suggestion of Mark at Panhadle performance. As soon as I have the cash I will get the cam and a Systemax 2 intake manifold, then I'll be able to throw it all on at once.
Hoping to see some good gains from all of this :)
 
Just thought I'd update. I have ordered the 75 mm Pro M MAF, and have acquired a set of TFS 170 heads. I've decided on a Lunati Voodoo cam (part 20350711) at the suggestion of Mark at Panhadle performance. As soon as I have the cash I will get the cam and a Systemax 2 intake manifold, then I'll be able to throw it all on at once.
Hoping to see some good gains from all of this :)


Wow. for $50 more you could have bought a custom ground cam to your specs from Ed Curtis @ FTI.
 
Just thought I'd update. I have ordered the 75 mm Pro M MAF, and have acquired a set of TFS 170 heads. I've decided on a Lunati Voodoo cam (part 20350711) at the suggestion of Mark at Panhadle performance. As soon as I have the cash I will get the cam and a Systemax 2 intake manifold, then I'll be able to throw it all on at once.
Hoping to see some good gains from all of this :)

TFS 170 heads are a good choice for a 302. Are those heads complete with valves & springs? If so, are those springs going to work with your cam choice? Did you get them used? Any work done to them?
 
Mikestang I did consider that. I haven't actually bought the cam yet, so I may go that route, but from everyone I've spoken to outside the forums, I've been told it's unnecessary.

Foxmustanglvr, The heads are complete with valves & springs, I did buy them used, checked them over carefully. They were at a shop that belongs to a friend of a friend, he says they were never installed, and they look that way, but I will probably get them resurfaced anyway.
 
Off the shelf cams are decent-good so long as they compliment your combo well and many people have great success putting down near (stock) block splitting HP with them. Custom grind cams help you squeeze that little bit of extra HP potential out of your engine but for me personally I think they're more for high $ builds and people that want to improve the track ET's.
 
Off the shelf cams are decent-good so long as they compliment your combo well and many people have great success putting down near (stock) block splitting HP with them. Custom grind cams help you squeeze that little bit of extra HP potential out of your engine but for me personally I think they're more for high $ builds and people that want to improve the track ET's.

I agree for the most part but the difference in price is only $50. If it was a TFS or Comp cam around $200 then I'd say go with the OTS cam. It may not get you much more HP, but will help with the driveability for sure.
 
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