Topic: 4v headers

[Tim175]

will they work on 2v engine by any chance? Thanks

[Jeff73Mach1]

Yes, but they are overly large and will reduce back pressure and scavenging and will cause a loss of low RPM torque.

[Tim175]

So i should just get a 2v set?

[Jeff73Mach1]

Unless you intend to upgrade to 4v heads I would go with the headers meant for a 2v engine.  An upgrade to 4v heads isn't an upgrade in my opinion unless you are going to use either the smaller quench chambers that give higher compression or domed pistons.  The 2v heads give a little better low end torque and flow well enough for a pretty decent engine build.

Higher compression is a nice way to boost horsepower,but if it is a daily driver, you will also need octane booster and premium gas to get the most out of your engine.  If you are not rebuilding the bottom end at the same time, I would not change to the higher compression heads as any wear on the rings will be exacerbated.

My stock 4 v Open chamber heads exhibit valve float at around 6200 rpms which suggest to me that a set of better springs would be a big improvement in keeping the valves under control.

[Tim175]

Alright that makes sense, thanks for the info.

[Tim175]

Would this be a good set? Ive been told that long tubes are better, and ive also been told shorties are better so i dont know, any opinions/advice would be awesome.

http://www.summitracing.com/parts/HED-88220/

[Jeff73Mach1]

I had hedman headers in my 72 and they were okay, but very prone to blowing exhaust gaskets.  I have had better luck with Hooker brand headers fitting well and sealing.  http://www.jegs.com/i/Hooker/520/6921/10002/-1

I also think they sound better.  Short tubes for torque, long tubes for power further up in the power band.  Add a crossover pipe in your exhaust too (Let a shop fabricate it for a couple of bucks, don't waste money on buying a premade one)

[Tim175]

Thanks for the reply. Yeah ive always like hooker better than hedman, the 4v set i found was hooker so. I like the hooker set you showed me, and when you say a couple bucks, what are we talking $50? $100? Thanks

[Jeff73Mach1]

No I think last time I had one added to an existing system they charged me $35.00

[Tim175]

Oh ok cool, thanks a lot.

[jhutch]

Good tip on getting crossover fabricated by shop rather than spending the $100 for a pre-made...  One quick note about Hooker headers: they have TERRIBLE ceramic powder-coating!  I bought my wife a set of full-length ceramic coated Hookers for her 455 Buick GS and they were rusted after 8 months!  This is a garage-kept car that doesn't see bad weather.  If you go with the Hooker headers, get them uncoated and have the coating done by someone reputable, like Jet-hot.  I spoke to a lot of different ceramic coating shops and two separate shops told me that Hooker approached them to do their powder coating, but wouldn't pay enough to even cover their costs.  Luckily for me, YearOne stood by their stuff and replaced the rusted set with another for free - but I still had to go through the de-install/re-install nightmare.  So far the second set is holding up ok, a little rust on the down tubes after 1 year but not nearly as bad as the first set (I got a second set pre-coated on the chance the first poor coating was a fluke).  Just went with Hedman headers for my 69 Mach I - I'll let you know how those work out...

[Jeff73Mach1]

I recommended their painted headers and I agree that their ceramic coating is a waste of money.  At 179.99 a set, I'll most likely wrap mine and void the warranty and replace them when they rust out.