Trying to build the perfect 420A head for a turbo

[Kuhn]

I've heard that port and polishing the 420A head doesn't do too much on it's own. That's why I want a 5 angle valve grind, .1mm oversized valves, titanium valve springs, adjustable cam gear, and some crower stage 3 cams. I need some insight... Am I missing anything, and what brands should I use? This will be used is conjunction with a bottom end from Howell Automotive (http://www.howellautomotive.com/Howe...roducts_id=552), and a HRC Turbo Kit with the 25G turbo.

Has anybody heard of a kit that includes all of this? Most important, has anybody heard of a good shop that could do all of this correctly?

[1stGenRocks]

dont forget stronger retainers for the upgraded valve springs. you can check out 2gnt.com they probably have soem sites that sell complete raqce heads for 420a's.

[Kuhn]

I'll check out 2gnt.com. Slowboyracing.com has a 420A head, but it doesn't include everything... Just a 5 angle valve job with upgraded valves. Thanks for the help!

[Kuhn]

I just got an idea from a friend going to Oakland U. for Mechanical Engineering... He suggested that I ceramic coat the whole head. I researched this, and apparently it helps out a bunch since it insulates extremely well (http://www.off-road.com/rock/ramproline/).

Apparently .1mm oversized valves don't necessarily help flow more air, so that idea may get scrapped.

Overall, SlowBoyRacing.com told me that they can build the head I want (Minus cams and cam gears) for about $1700. That's a Stage III P&P, stainless steel valves, upgraded springs, and titanium retainers. They say that they've made over 710hp with this head... :-D

[scottsee]

yeah, you wont need oversize vales. i dont think 5 angle job will provide you with that much more flow, after a couple thousand miles the grind will look resemble a 3 degree job. i believe the 420a and 4g63 heads are both 3 degree stock angle. i hate giving bad info, hopfully somone can say for sure.

you can go as hog wild as you want on head components. i would suggest mannly valves. SBR says they flow a little better. the choice of springs, retainers, cams is all up to you. each provide diffrent vareations of functioality. you really need to nail down the turbo you'll be using. once thats set in stone, being a 25g or whatever. then build your head to acomidate the airflow you'll need to effecently run that specific turbo.

[Kuhn]

Sounds good. Thanks for the input.

[Whathits14]

I would go full Ferrea valvetrain upgrade, titanium retainers, springs valves etc. Crower cams are good, gets my That 25g is a beastly ass turbo! Might even be a lil overkill, 20g's can get you easy into the low 11's and occasionally some high 10's. Never seen it done on a FWD car tho... that is really the major drawback from NT's.

As for shops, well it really depends on where you live. IMO Roadraceengineering.com is one of the best dsm shops around. Its in So-cal. They know their shit. Don't take it to a normal mechanic, they will charge you way to much for it. Find a performance shop, even better is one only for dsms. I would do the turbo install myself, its not that difficult, but a engine is a pain to put in.