randomnine7

iTrader: (23)

so im just trying to get a few more ponies .wondering how much i can safely mill off a set of 853 heads with out having to worry about flycutting or having ptv clearance .

i can get the machine work done cheap and i figures i might as well when i get the new springs installed .

ill be running a 228/228 588/588 lift tsp cam ..

my question is should i run the thinner .040 cometic head gasket or run a stock thickness cometic head gasket and or mill the stock 853 corvette heads .025 or .030 ?

ill do a ptv check but wondering whats a better idea for a weekend/track car
along with fresh gaskets arp head bolts ill also be instaling a set of katech rod bolts and ls2 timing kit .

how much can bumping up the cr net in hp increase ?

00MaroonZ28

iTrader: (3)

If you mill the heads you shouldn't have a problem with PTV clearance with the 228R cam. Typically, it's a 50 hp difference for every 1 point of compression on an LS1 block.

gayslowassNALSjunk

iTrader: (2)

That doesn't sound right.

'02 WS6

iTrader: (73)

Mill .015-.020 or 2cc, and run a .040 cometic. That's what I have with torquer 2 (232/234 .595/.598) and it clears fine. It put me right @ a nice 11.04:1 compression.

luckyhenriksen

iTrader: (1)

Ya that seems like a lot of difference

ls1wannabe

iTrader: (2)

For every full point its about 3~4% of a gain. Not even close to 50

regency

iTrader: (15)

1 point increase is usually 15-20 HP. I have 243's milled .010 with .040 cometics and im at 11.15:1 CR

davered00ss

iTrader: (4)

SO my AFR heads gained me nothing, and it was all in going from 10.0 :1 to 11.1:1 compression?

With the cost of used 243 heads, if you are taking your heads off, I would just replace them with 243's.

DONAIMIAN

iTrader: (18)

For the thin Cometics you're looking at ~150 for the set.

You can mill the heads, and run a stock gasket and still come out cheaper than that. Also if you have to pull the heads for whatever reason, stock gaskets are cheap.

ZMONSTER!

iTrader: (9)

Couple things I dont know a whole lot about but hopefully others can comment on.
As far as the head gaskets the GM MLS are great, really hard to beat their price and reliability. Also you might want to find out how much the pistons come out of the block and then calculate your desired quench pad and get an appropriate gasket. As far as Ive seen around the head gaskets should be used to attain the proper quench, and then mill if you want any additional compression.
Ive also read, so take it for what it is, that with the cometics the only way to make 100% sure that they will seal is to get the block decked.
As far as a 228R, great cam, and you shouldnt have any issues milling the heads down. get the heads down to 62cc, measure PTV and call it a day.
You said your installing new springs, are you planning on lifters as well? Let me tell you I wish I had changed mine with my H/C, cause now 8 thousand down the road Im doin them anyway!

randomnine7

iTrader: (23)

yeah im going to get push rods and lifters too ..
how are the gm mls price compared to the cometics ? and i heard there reusable up to 3 times ?

and another thing is im wondering i have a vett block dnt knw what year it is it has a 12559378 serial # on the block . and dnt knw if i should install rod bolts or not it has aprox 60k miles . . im not gona spin it past 6500 .. its a mild build and prob wouldnt be worth it to spin it that high for such a small cam milled heads and a ls6 manifold .

and i heard katech dosent have the rod bolts available right now .

randomnine7

iTrader: (23)

**** are the gm mls gaskets really only $48 ?? im not planing on decking the block

so how much can i mill of the 853 heads . looking for sumthing in 11cr . .035 ? or so >?

ZMONSTER!

iTrader: (9)

**** on summit the other day LS1 MLS were 29.99 a pair.
search changing rod bolts, I guess there is only one way to do it right and alot of people screw it up. Im still using stock bolts and mine is fine shifting 6500 ish

randomnine7

iTrader: (23)

ur in fresno zmonster ? im out form modesto ! yeah anyways i have a built forged 347 in a rx7 that has arp rod bolts but the rods were checked for out of round when i got all the machine work done .. and im guessing ima use the katech im not trying to risk it and spin a bearing . sokatech is the way to go , but i heard they werent available right now ?

i might just hold off on the rod bolts till the motor get some decent rpm stuff .

ZMONSTER!

iTrader: (9)

whats up modesto homie!

The APRs should be fine, why do you want to go to the katech's?

randomnine7

iTrader: (23)

ive had alooooot of mixed reviews about putting in a set of arp with out resizing the rods ...

so im not sure i would rather go with the cheapest route so its up the air .. looks like 50/50 with the arp rod bolts ..

ZMONSTER!

iTrader: (9)

well hes already running the ARP rod bolts, so why go through all the hassle of switching to katech's?

quick346

iTrader: (4)

you can reuse cometics. if you take care of them while removeing them and clean them properly

I copper spray mine with 3 coats.

and then spray the **** out of them every weekend with a 150 shot with no problems

lots of peaple say you can't but if done right you can

I run the .040 cometics with 59cc afr's

quick346

iTrader: (4)

as long as it is 99 or newer dont worry about it.

I have spun my stock bottem end to 7300 a thousand times.


and put arp's in my last block and spun a bearing after 2k miles but that was after 3 back to back 165mph runs 1 qt low on oil.

if you dont spin over 7k with a 99 or newer save youre money

and if you really don't care like me spin the hell out of it

peaple spend thousands on what ifs i paid 600 for a 12k mile short block fly cut the pistons put my pump ,cam ,chain and gears in it and back on the road