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between Mopar and FWD there is many. Depending on the engine build normally there are few for each build. So you need to size your cam with your engine well.
 

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They're more for an extensively modified engine that would perform well without forced induction. If you're not boosting much more than stock, an FWD F2 cam would probably do quite well, but you'd have to do some exh. mani. & head porting to notice it much. Bigger cam=better low end (torque)=worse top end (horsepower) IMHO, a stock roller cam is the best for a high boost engine. Since yours is an '88, you should already have a roller.
 

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ok thats what i waslooking for. if a stock cam is best for high boost, then what are the advantages of those other cams?
Believe me life is a lot easier when your making more HP at 20 PSI than the other guy at 35 PSI of boost.

Remember the fastest 8v FWD of all time, Carlsons Focus, used a .600"+ cam. You guys are too stuck in the old days, big cams work with a built engine. Some people on here have built engines, others don't.

Most just think of the S60 cam when talking power at high boost levels. The most famous of people bad mouthing big cams also ran a constrictive intake and a stock plenum. You must do it all to use a big cam with high boost. An F2 is NOT a big cam, the F3-F4 are because of the duration. consider also that to make a Turbo cam you need to adjust the whole thing. Building a cam isn't just lift and duration. The S60 doesn't have the better lobe sepperation and centerline of the new cams. Even the old Taft cams make more power than the S60 did.

With most over the years they see 35 PSI on the gauge and think thats getting into the engine. Instead the boost is backing up in the intake running your gauge up and not getting into the engine. When this happens the exhaust pressure in the turbine is unreal high and trying to shove air through a straw is seriously working the turbo. The all important presure differental comes into play. You have air stacking in your intake, but not your intake valve. The exhaust has huge pressure right up against the exhaust valve. So instead of solving the problem, many TD racers just slap in the smallest cam they can. Tiny cams are a band aid for a screwed up set up, sad fact. Want to know how easy it is to see why big cams work for most racers? Easy. Take a look at every turbo race intake out there, on any 4 cylinder. Super short and huge runners, huge plenum. Then take a look at many TD race engines, tiny super long runners and a tiny plenum. News flash, we have everything the rest of the world uses in header, turbo and intercoolers. Are heads don't flow so bad as to make only 1/4 the power 16v engines make with 2/3 the air flow.:rolleyes:

Here is an easy way to show you what our heads should do. If the head is the problem. A 1,600 HP Ecotech has about a 300 CFM intake port. A commen big valve head on many flow benches really flows about 200 CFM. 1600 * 200 / 300 = 1,066 HP. Just air flow capabilty in an apples to apples comparison. Below 2,000 LBs and all the weight shifted a TD race car can run 10s with 450 HP, thats barely over 350 WHP. With street cars that have the weight moved farther back engines with big plenums and shorter runners are making over 400 WHP and are breaking into the 10s.

So like every other engine on earth a big cam doesn't work with a stock intake, sorry. those of you still running stock intakes and intakes with a little porting need to consider the F2 as your big cam. Or run massive boost and a stock cam. Today building it outright and paying some one else to do the work. Buying nearly the best intake, a fully ported and polished 2 piece lower with a new plenum and fuel rail can cost nearly $700 from scratch.Thats the biggest runners were have matched with a lot of porting and polishing getting it danerously thin. Then a big plenum with the right volume and making the runners funnel and shorter. then a billet fuel rail that flows more and fits with the plenum.

2 piece, $200
fuel rail, $100
porting, $100, $160 with a 655
new plenum, $300

Night and day better for a bigger cam and more power. Still restricting a big valve head. Falls half way between a +1 and a big valve in flow. Only thing left now is another $500 on extrude honing, which will require welding in places and some work at the bolts. So that would bring an intake clear to $1,200 starting from scratch to keep up with a big valve 782, maybe.. Think I'm nuts? Ask every big valve head guy if his head has been flowed with the intake and either flows the same or more, get ready for hearing excuses.
 

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ok thats what i waslooking for. if a stock cam is best for high boost, then what are the advantages of those other cams?
what we should do is a combo chart. Showing mods and then a cam. Like Mopar shows in there catolog

stock engine and setup
S1, F1, TBI, turbo roller

Ported manifolds, mildly ported head, better exhaust (mandrel 2.5-3.0), T3 turbo.
F2 or smaller

heavily ported head, +1 valves or big valves, heavily ported intake and exhaust, 3" exhaust and a .63 housing hybrid, better flowing intercooler. 52mm TB
F2 or S2 street 25-30 PSI, F4 or S3 race car 25 PSI, 88 TBI or turbo roller past 30 PSI

Heavily ported big valve head, heavily ported intake with shorter runners and a big plenum ( same CID as the engine) and big 58 TB, TU header and a large turbo, stage 2 or 3 turbine wheel with .63 housing, 3-4" exhaust, 700+ CFM intercooler. 72 lb injectors ( 85s ran at 45 PSI ), 3" intake, 2.5" boost lines

F4 or S3 street, S60 for race, shouldn't go over 30 PSI, should run out of fuel

Same as above, bigger turbo, a laggy huge thing like a GT35. A real tube header like Stammers or FWDs that is a 4 into 1 or a 4 into 2 into 1 that cuts reversion. Consider a hand made sheet metal intake with larger than stock runners and a plenum now with 1.5 times your CID. 85 lb injectors, 1000+ CFM intercooler, 4" intake, 3" boost lines

S60 or F5, shouldn't go over 30 PSI without running out of fuel

What do you guys think? Pretty ballenced cam range.:)
 

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It's all relative, with the right set-up you can still make 350whp with a stock cam. Having said that, a taft stage 3 or FWD F4 in the same mtr would prob net you 20+whp and more power under the curve to boot!:eek:
 
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