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Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Hotrodding Basics> I have stock Gen IV 454 & 781 Heads, Compression ????
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Topic Review (Newest First)
04-22-2013 10:04 AM
wild_man84
Quote:
Originally Posted by matts37chev View Post
yes, I think the 2.19/1.88 are what you want
I dont think you want the 2.25 intakes, they are too big for 781s
Im curious as why you think the 2.25intake is to much for 781's? not questioning you, Only getting more aware. Because its official, the heads are complete, clean,worked, and ready to bolt on. They are 2.25in/1.88exh
04-22-2013 05:23 AM
wild_man84
Quote:
Originally Posted by vinniekq2 View Post
tech has been very thourough in his posts.I sugguest you follow his guides as he is the most accurate person here.


Yes, He is VERY knowledgable! He put me over the top with his posts. I just Finally had some specifics on specs, so thats why I was getting back with this thread.
04-22-2013 01:00 AM
vinniekq2 tech has been very thourough in his posts.I sugguest you follow his guides as he is the most accurate person here.
04-21-2013 08:22 PM
wild_man84
Quote:
Originally Posted by vinniekq2 View Post
how far down the bore is it to the top of the piston?piston type? flat top,dish,volume of valve reliefs?
Read first page. Tech inspector
04-21-2013 08:03 PM
vinniekq2 how far down the bore is it to the top of the piston?piston type? flat top,dish,volume of valve reliefs?
04-21-2013 07:57 PM
wild_man84
Quote:
Originally Posted by vinniekq2 View Post
what is your deck height and gasket thickness?
9.8DH

not sure the gaskets thickness. It's at the shop I just used typical. So. Any number is fine.
04-21-2013 07:26 PM
vinniekq2 what is your deck height and gasket thickness?
04-21-2013 06:26 PM
wild_man84
Its been forever but Im finally back

Ok so... Im not sure if anyone is familiar with Steve Schmidt racing. but thats where i had the heads worked. This is the parts and total....
Competition valve job
mill heads to 110cc (.045")

comp cam K-kit,heads worked and assembled, shipping,valves, rockers..

3,500.00.... ouch. but honestly if you subtract parts. only have 1072.00 in labor/head work

The new spec's are.....
781 heads cc 110
valves int2.250" exh1.880"
overall length int5.244" exh5.422"

spring
installed height/pressure===1.920"/150lbs(+.050 lock)

I know Ive got lots to learn. and Im trying to. I haven't installed these heads yet. Im planning on it by next week. (im off work for a few weeks) So, I dont have an exact on the piston/valve measurement yet. Im starting to think Im going to have to have the bottom end worked. Im trying to get out of that for now because im already pushing my budget.

Can someone help me out on seeing where im at for compression. If Ive paid attention. Im showing 8.2:1.. Thats not enough. I need a min of 9:1. IF!! Im wrong, and I hope I am haha, that my compression is already above that. Than, Im golden. If not!!!! then whats my cheapest way out? changing the pistons myself with domes or new crank. Just please take into consideration Ive performed top end work. Ive been around bottom end work. But never done it myself. I have read the books and reread them. But its a lot to risk, so the worry is up on the scale. lol

I know these heads or going to be nice. This valve and bowl job is at its max. I didnt get a flow rating though smh

The engines out. but I haven't started any work yet. Im at the point of decision making.

If you want to know what my budget is left.... Im wanting to get away with oil pan gasket and seals replaced.. Thats where I want to be. Very max...1200-1500 that's including any labor and work. but that's taking away from the accessories parts I need as well. I hope this is enough information to get some ideas going. I need all the help i can get.

btw---I haven't ordered the rockers yet.
cam specs are
11-432-8 - Xtreme Energy

http://www.compcams.com/Company/CC/c...?csid=444&sb=2
03-04-2012 07:02 PM
matts37chev
Quote:
Originally Posted by wild_man84
Unfortunately, the heads are already at the machine shop. I will be discussing work and prices tomorrow. If it gets too close to $2,000 then, Im just going to have them basically worked and just keep on hand for a back up. And just buy Aftermarket, again, as ya'll tried to tell me lol.... Mistakes/learning curves always have a price tag. Ill be getting those books Thursday and Friday.
if the guides are ok, you can still put the bigger valves in and get them dressed up for cheaper than a new set
if the guides need changed also, that will probably make it close to buying a new set, for not a lot more money

and when its all said and done, if put a lot of money into those 781s, its OK because they are/and you will have, a good set of heads
03-04-2012 05:44 PM
wild_man84 Unfortunately, the heads are already at the machine shop. I will be discussing work and prices tomorrow. If it gets too close to $2,000 then, Im just going to have them basically worked and just keep on hand for a back up. And just buy Aftermarket, again, as ya'll tried to tell me lol.... Mistakes/learning curves always have a price tag. Ill be getting those books Thursday and Friday.
03-04-2012 05:30 PM
123pugsy
Quote:
Originally Posted by wild_man84
Getting Excited, Been wanting to do this for some time now! Not only that, actually have had a few minutes lately.

Just ordered 5 books.. The three you recommended and one about blue printing and another one also...

Right on.

Read them all before buying any parts or getting any machining done.
03-04-2012 05:27 PM
wild_man84
Quote:
Originally Posted by 123pugsy
Glad to see you've slowed down.
I almost couldn't keep up to your posts, you were talking so fast.

Getting Excited, Been wanting to do this for some time now! Not only that, actually have had a few minutes lately.

Just ordered 5 books.. The three you recommended and one about blue printing and another one also...
03-04-2012 05:27 AM
123pugsy
Quote:
Originally Posted by wild_man84
I think so too... Going to try and get them on kindle but if not, ordering tomorrow...

Glad to see you've slowed down.
I almost couldn't keep up to your posts, you were talking so fast.
03-03-2012 10:02 PM
wild_man84
Quote:
Originally Posted by matts37chev
I dont have that one but I do have this one and this one , both are pretty old and have some dated info, but it still applies

all of them would be good reading for you wildman

I think so too... Going to try and get them on kindle but if not, ordering tomorrow...
03-03-2012 08:24 AM
matts37chev
Quote:
Originally Posted by 123pugsy
I just got the BBC book by David Vizard.

I just started reading it but looks OK.
May be a good investment before deciding to buy parts.

Book
I dont have that one but I do have this one and this one , both are pretty old and have some dated info, but it still applies

all of them would be good reading for you wildman
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