330CubeGt Posted August 17, 2012 Report Share Posted August 17, 2012 Link to comment Share on other sites More sharing options...
Venom351R Posted August 17, 2012 Report Share Posted August 17, 2012 valve dia for the intake/exhaust seems so small compared to the aftermarekt lol Link to comment Share on other sites More sharing options...
330CubeGt Posted August 17, 2012 Author Report Share Posted August 17, 2012 Yep, That's why the 302 based motors run like raped ape's when you slap a set of well flowing heads on them. Link to comment Share on other sites More sharing options...
scottydsntknow Posted March 25, 2013 Report Share Posted March 25, 2013 Agreed, except for the GT40 series, all latemodel OEM sbf heads were garbage. Even the GT40 stuff was too small but at least it was serviceable. Link to comment Share on other sites More sharing options...
revhead347 Posted March 27, 2013 Report Share Posted March 27, 2013 Small valves mean good velocity and low end torque.Kurt Link to comment Share on other sites More sharing options...
95opal Posted March 28, 2013 Report Share Posted March 28, 2013 Small valves mean good velocity and low end torque.KurtWhich is all good for mild street cars but if your looking to make real power they are a waist of money Link to comment Share on other sites More sharing options...
revhead347 Posted March 28, 2013 Report Share Posted March 28, 2013 I agree. But most of the guys who do the stock ported head jobs don't change the valves out.Kurt Link to comment Share on other sites More sharing options...
95opal Posted March 28, 2013 Report Share Posted March 28, 2013 I agree. But most of the guys who do the stock ported head jobs don't change the valves out.KurtBecause for the price of replacing valves its eaiser and cheaper to pick up used aluminums. I know thumper was getting some good #s out of the heads he was doing but not sure if hes still doing them. Link to comment Share on other sites More sharing options...
revhead347 Posted March 28, 2013 Report Share Posted March 28, 2013 I think most of the guys found that there just wasn't any gain in changing the valves. The heads just can't flow enough to justify bigger valves. Price definately plays a role too. Most of those stock head combos that make good power have a good bit of compression on the engine too.Kurt Link to comment Share on other sites More sharing options...
scottydsntknow Posted March 29, 2013 Report Share Posted March 29, 2013 No, I've been there and done that, there is no value in getting the GT40s done like crazy. The value in GT40s is getting a set of them (or Ps) from a JY for like $100 and then having them checked/cleaned, maybe milled just enough to true them up if they need it, do valves/locks/retainers/springs and then bolt them on. You should be into them for about $400 at that point. New valves/port polish job etc... is going to bring your total cost up into the $700+ range unless you are competent at porting and do all the work yourself, then have at it. Anyway at that price point you can get or almost get a set of good used Twedges which will kick the shit out of even ported GT40s in every category and have enough "meat" on them where if you ever go bigger like a stroker or even a 351 based stroker you can send them out to be taken out to meet your needs. That said, the $400 set of basically new GT40 heads you can get if you go pull your own cores with good valves are a GREAT value as they'll give you a good 40whp bump over E7s for a minimal price, its even better with the GT40 intake which you should ALWAYS be running with them (or any 302/306 IMHO). Bone stock 93-95 Cobras routinely dynoed in the 240whp range vs the 195whp range of the GT. Ford obviously underrated the Cobras and from my personal experience with my current PI setup and years driving a 95 Cobra, the GT40 Cobra motors were basically 5.0 "PI" motors if that makes sense. My 98 with the PI motor swapped in feels VERY similar to my 95 Cobra and the bolt ons are basically identical for both cars before I did the HCI to my Cobra. In a nutshell, the GT40s are much maligned but if all you need is as much as the stock 5.0 block can handle, there is 0 reason to go with anything else. You can build a very VERY nice combo with them. Stock 302 shortblock, stock GT cam, GT40 heads, GT40 intake, all the "bolt ons" and a S trim with the fuel system to support it is pretty much perfect. A safe 450whp, completely stock drivability, you'll pass emissions no problem anywhere basically even Cali as they are OEM and 50 state legal and it will probably cost less than some guys' HCIs that make 150whp less than you and have drivability issues. Like I said, been there, done that, if I had it all to do over again I would have just thrown a S trim and a good fuel system on my Cobra and rolled with it. Link to comment Share on other sites More sharing options...
revhead347 Posted March 29, 2013 Report Share Posted March 29, 2013 I agree. My old engine builder used to do a pretty good set up E7s for $300. Much more than that and you are better off getting aluminum heads. I'm of the opinion that all the iron heads don't vary that much. I would rather pay $300 for a set of worked E7s then $200 for some junkyard GT40s.Kurt Link to comment Share on other sites More sharing options...
scottydsntknow Posted March 30, 2013 Report Share Posted March 30, 2013 Wonder how much he'd charge now tho... if still the same that is a hell of a deal if its valve job/mild porting to get them to flow like GT40s and all the spring/lock/retainer/seal etc... upgrades. If they still flow like E7s... I'd go for the GT40s. Off boost power is going to be WAY lower with unported E7s. If top end power is all one cares about though, plenty of stock E7 headed motors running around with 400+whp. I almost bought a 95 Roush with a S trim on it making 400whp back in 2003 but the guy wanted $13k and I smelled coolant and he wouldn't budge on the price. I paid less for my old 95 Cobra and it had 40k on it... man so many regrets and moments I wish I could go back and punch my 22 yr old self for doing stupid shit to it and then explain that even living in an apt with no garage is no excuse to not get a storage unit or something to keep that thing out of the elements at 50k original miles and never seen rain... man... Link to comment Share on other sites More sharing options...
revhead347 Posted March 30, 2013 Report Share Posted March 30, 2013 I'm sure the price has gone up. That was 1997 prices. I would guess in the $500 range. They flowed way better than GT40s though. I never had a set, but a friend of mine ran them. He ran 12.80@104 in a full weight hatch back with 3.73s, a Cobra intake and a Steeda #18 cam.Kurt Link to comment Share on other sites More sharing options...
wmfateam Posted March 30, 2013 Report Share Posted March 30, 2013 What are everyone's thoughts on the GT40X? Would you say they are worth the price compared to Twedge? Link to comment Share on other sites More sharing options...
revhead347 Posted March 30, 2013 Report Share Posted March 30, 2013 They are an entry level aluminum head. About the same as an Edelbrock Performer. They aren't too bad, but I wouldn't say they are as nice as a Twedge 170cc.Kurt Link to comment Share on other sites More sharing options...
OnyxCobra Posted March 31, 2013 Report Share Posted March 31, 2013 everything I've ever seen said says the stock '95 Cobra GT40 heads have a 64cc chamber. Link to comment Share on other sites More sharing options...
scottydsntknow Posted March 31, 2013 Report Share Posted March 31, 2013 They are an entry level aluminum head. About the same as an Edelbrock Performer. They aren't too bad, but I wouldn't say they are as nice as a Twedge 170cc.KurtBlargh... more ppl hating on the Eddy heads. They are great for a 302 based build, I made 301/325 through them and there are a few things I could have done differently to get a little more power than that. And that was on a set of fuel injectors that I later found out needed replacing. Link to comment Share on other sites More sharing options...
revhead347 Posted April 3, 2013 Report Share Posted April 3, 2013 Blargh... more ppl hating on the Eddy heads. They are great for a 302 based build, I made 301/325 through them and there are a few things I could have done differently to get a little more power than that. And that was on a set of fuel injectors that I later found out needed replacing.I don't hate on the Eddy heads. Back in the day, that was what you got. You got an Eddy RPM, an Eddy Vic Jr, and if you wanted more power than that you got a Canfield. That was pretty much what everyone bought. If you could find an old set of Trick Flow hi ports, that was cool. Then Trick Flow came out with the Twisted Wedge, but only the 170cc version. Edelbrock had at least 2 different generations of the RPM head. The old RPM heads flowed about the same as the GT40X. Then around 1999 or so, they updated the design, and the new ones flow much better. Personally I don't think there is any difference between the bare castings on an entry level head. If you lined them all up next to each other and put tape over the logos you would have a hard time telling them apart. At one point, Canfield was making all the bare castings anyway. I honestly think all the companies are selling the same head with a slightly different hardware package, finishing work and warranty; the twisted wedge being the exception.Kurt Link to comment Share on other sites More sharing options...
scottydsntknow Posted April 3, 2013 Report Share Posted April 3, 2013 (edited) Whatever happened to the Yates and Brodix heads? Wow I just had a flashback to 2001!Canfield 192/195s were badass though. Edited April 3, 2013 by scottydsntknow Link to comment Share on other sites More sharing options...
revhead347 Posted April 3, 2013 Report Share Posted April 3, 2013 Whatever happened to the Yates and Brodix heads? Wow I just had a flashback to 2001!Canfield 192/195s were badass though.Yeah I remember that. If you wanted a step up from the Canfield 192cc you had to go straight to a Yates or a Brodix full out race head. I'm still running the Canfield 192cc heads I bought in 1999. I just had them redone. That was an awesome company to deal with, it's a shame they went out of business. I liked the slogan that came up as soon as you logged into their website: "If you are looking for the nickel special, you are in the wrong place."Kurt Link to comment Share on other sites More sharing options...
scottydsntknow Posted April 4, 2013 Report Share Posted April 4, 2013 Honestly seems like not too much has changed in 5.0 land. Different players, Vortech is still there, stock blocks still blow up at 500hp, people still ask stupid questions about how to get 300hp out of bolt ons and treat a 351 swap like it is some sort of brain surgery. The Modular world... now THAT has come a long way and the more I learn about these little 281s, the more I don't think I'll ever go back to a 5.0 motor. The ONLY way I might go back is if insurance companies start requiring monitor thingers like that commie Progressive plugin that goes in your OBDII port. I will find a clean 94/95 or Fox with OBDI or earlier so fast to be exempt it isn't even funny. Link to comment Share on other sites More sharing options...
revhead347 Posted April 4, 2013 Report Share Posted April 4, 2013 Yeah, I agree. The 281 was a hp sucubus for the first 7 or 8 years it was in the Mustang. There really wasn't much available. There still aren't too many high hp N/A 281s running around. Keep in mind, the driving habit monitors will probably always be incentives. It might become cost prohibitive to have a car without OBD2 because you can't run a monitor on it.I'm really hoping the new Coyote catches on with the aftermarket. I think that is the future.Kurt Link to comment Share on other sites More sharing options...
