6.6l?
6.6l? Ok guys, I just fraged my mill. Broken crane spring + droped exhaust valve= cracked # 2 cylinder. Oh well, **** happens. Iam going with the iron block due to the fact, that I can reuse all the sheet metal and some LS-6 heads that I have laying around.
1. What is the bore size of a 402cid, is it 4.00 inches and the stroke 4.00 inches aswell making it a 402cid and translates to a 6.6L?
2.What is the biggest intake/exhaust valve that I could go with on a set of oem heads and what port and polish level should I go with, should the heads the be milled just to clean up (true up)?
3. What should the head gasket thickness be?
I wanted to reuse my my G5X2 112 cam, comp push rods(7.4) wieand intake comp cams roller rockers and all sheet metal.
I just want a street beast that can handle a 150 shot and knock around the local street scene w/ some big rear horse power.
1. What is the bore size of a 402cid, is it 4.00 inches and the stroke 4.00 inches aswell making it a 402cid and translates to a 6.6L?
2.What is the biggest intake/exhaust valve that I could go with on a set of oem heads and what port and polish level should I go with, should the heads the be milled just to clean up (true up)?
3. What should the head gasket thickness be?
I wanted to reuse my my G5X2 112 cam, comp push rods(7.4) wieand intake comp cams roller rockers and all sheet metal.
I just want a street beast that can handle a 150 shot and knock around the local street scene w/ some big rear horse power.
TECH Senior Member
Joined: Mar 2004
Posts: 14,620
Likes: 17
From: BFE
Originally Posted by tylerdurden
Ok guys, I just fraged my mill. Broken crane spring + droped exhaust valve= cracked # 2 cylinder. Oh well, **** happens. Iam going with the iron block due to the fact, that I can reuse all the sheet metal and some LS-6 heads that I have laying around.
1. What is the bore size of a 402cid, is it 4.00 inches and the stroke 4.00 inches aswell making it a 402cid and translates to a 6.6L?
1. What is the bore size of a 402cid, is it 4.00 inches and the stroke 4.00 inches aswell making it a 402cid and translates to a 6.6L?
2.What is the biggest intake/exhaust valve that I could go with on a set of oem heads and what port and polish level should I go with, should the heads the be milled just to clean up (true up)?
3. What should the head gasket thickness be?
I wanted to reuse my my G5X2 112 cam, comp push rods(7.4) wieand intake comp cams roller rockers and all sheet metal.
I wanted to reuse my my G5X2 112 cam, comp push rods(7.4) wieand intake comp cams roller rockers and all sheet metal.
I just want a street beast that can handle a 150 shot and knock around the local street scene w/ some big rear horse power.
G5X2 is 232/240 and will be a good street friendly cam with plenty of trq
2.02 on stock seats, you should choose your piston relief size and .050 6.0 MLS gasket, .010 piston out of hole and mill accordingly to get best DCR for that cam.
Thanks Predator Z for you help. Just clearification about the piston .010 out of the cylinder bore. Is it safe to state that the use of a .050 thick gasket with that type of piston, would be that .040 is actully be used and if that same piston had a -2 cc dished out then it would render my cylinder heads from a 63cc (02' ls6 ) to 65cc.
I guess that 2.02 would be cost effective with a 2.5 port and polish stage. If a bigger valve was desired then a aftermarket head would be needed for that same machine price.
Thanks Predator Z for you help. Just clearification about the piston .010 out of the cylinder bore. Is it safe to state that the use of a .050 thick gasket with that type of piston, would be that .040 is actully be used and if that same piston had a -2 cc dished out then it would render my cylinder heads from a 63cc (02' ls6 ) to 65cc.
I guess that 2.02 would be cost effective with a 2.5 port and polish stage. If a bigger valve was desired then a aftermarket head would be needed for that same machine price.
TECH Senior Member
Joined: Mar 2004
Posts: 14,620
Likes: 17
From: BFE
Stock seats are 2.02, so if you want to put bigger valves, you need bigger seats.
most builders who know their job well will setup pistons .010 out of hole. Why? Because then you can run stock MLS 6.0 (.050 compressed) and get .040 quench which is ideal for street.
More out and you'll need thicker gaskets. Less and you have to run thinner gaskets.
MLS GM are not only one of the best in quality but also best priced. They don't leak either.
In the hole is bad for any type of boost including nitrous.
As far as relief cc goes, this is where the crucial choice comes and has to be chosen to get a DCR of 8.5>8.7 on that cam.
As per my calculations with 6.125 rods, with that cam on a 112+4, 4.00 stoke, 4.00 bore, .050 gaskets, .010 out of hole, 63cc chambers.
you'll need 10 cc valve reliefs (dish), for a 11.13 SCR and 8.66 DCR.
most builders who know their job well will setup pistons .010 out of hole. Why? Because then you can run stock MLS 6.0 (.050 compressed) and get .040 quench which is ideal for street.
More out and you'll need thicker gaskets. Less and you have to run thinner gaskets.
MLS GM are not only one of the best in quality but also best priced. They don't leak either.
In the hole is bad for any type of boost including nitrous.
As far as relief cc goes, this is where the crucial choice comes and has to be chosen to get a DCR of 8.5>8.7 on that cam.
As per my calculations with 6.125 rods, with that cam on a 112+4, 4.00 stoke, 4.00 bore, .050 gaskets, .010 out of hole, 63cc chambers.
you'll need 10 cc valve reliefs (dish), for a 11.13 SCR and 8.66 DCR.
