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The 37 has a later intake close than the 204; 38* vs 34*. Where the SE204 would work well at 9.6-9.8, the 37 will like 9.8-10 better.
The results that I have seen (no personal experience) show that the 1.7 ratio rockers are worth the investment. Some just install them on the intakes, others install on intake and exhaust; don't know if one is better than the other. Your heads will need porting and 1.9 intake and 1.6 exhaust valves to take advantage of the extra lift. Clay the pistons and check for piston to valve clearance if you are using HD pistons. Many times the valve reliefs, particularly the intake, need to be opened up to avoid what is shown in the attached photo. Most aftermarket pistons have already addressed that issue.
They are getting the 1.9 and 1.6 as we speak , well the heads are away getting done lol.
Withe the way my heads are getting don I will be a bit low using the 204 with the 88 ci engine . but when I bump up to a 95 or 98 it sould be right in that range for the 37s.
Im getting the heads decked .030 and using a .030 head gasket .
F.k.
 
They are getting the 1.9 and 1.6 as we speak , well the heads are away getting done lol. Withe the way my heads are getting don I will be a bit low using the 204 with the 88 ci engine . but when I bump up to a 95 or 98 it sould be right in that range for the 37s. Im getting the heads decked .030 and using a .030 head gasket .
F.k.

I forget what pistons you are using; do they have a dome? If flat tops, static is only going to be 9:2 with a .030" cut and CCP about 175psi; pretty low and even lower with the 37s and a later intake close. The 37s will be softer on the bottom than the 204s unless you do have a domed piston.

A .060" cut on the heads will bump static up to about 9.6; not a bad place for the 204 and, all things being equal, 10.2 at 95" with the 37s. The difference between the two configurations will register on the butt dyno.;)
 
I forget what pistons you are using; do they have a dome? If flat tops, static is only going to be 9:2 with a .030" cut and CCP about 175psi; pretty low and even lower with the 37s and a later intake close. The 37s will be softer on the bottom than the 204s unless you do have a domed piston.

A .060" cut on the heads will bump static up to about 9.6; not a bad place for the 204 and, all things being equal, 10.2 at 95" with the 37s. The difference between the two configurations will register on the butt dyno.;)
When I go 95 or 98 it will bump up quite a bit
I forget what pistons you are using; do they have a dome? If flat tops, static is only going to be 9:2 with a .030" cut and CCP about 175psi; pretty low and even lower with the 37s and a later intake close. The 37s will be softer on the bottom than the 204s unless you do have a domed piston.

A .060" cut on the heads will bump static up to about 9.6; not a bad place for the 204 and, all things being equal, 10.2 at 95" with the 37s. The difference between the two configurations will register on the butt dyno.;)
I might go to a 98 but ya 174 psi cranking with the 88ci and 204 when I bump to 95 it goes up to 184 psi with the 37 and in the 98 it bumps up to about 190 psi. I forget the corrected comp. but it give me the leaway to go to a 98 ci
No been told to go to flat tops because I was told that the domed pistons in a twin cam can cuase detonation . I thought I would keep to a bit of a milder side of things . I can always go to a .026 cometic head gasket if I need to bump it up a bit .

F.K.

When I go 95 or 98 it will bump up quite a bit

I might go to a 98 but ya 174 psi cranking with the 88ci and 204 when I bump to 95 it goes up to 184 psi with the 37 and in the 98 it bumps up to about 190 psi. I forget the corrected comp. but it give me the leaway to go to a 98 ci
No been told to go to flat tops because I was told that the domed pistons in a twin cam can cuase detonation . I thought I would keep to a bit of a milder side of things . I can always go to a .026 cometic head gasket if I need to bump it up a bit .

F.K.
It bumps the psi from 156-174 and corrected comp from 8.01 to8.88 I think not a bad bump . Ill check ot the thiner gaskes in the calculator
F.K

When I go 95 or 98 it will bump up quite a bit

I might go to a 98 but ya 174 psi cranking with the 88ci and 204 when I bump to 95 it goes up to 184 psi with the 37 and in the 98 it bumps up to about 190 psi. I forget the corrected comp. but it give me the leaway to go to a 98 ci
No been told to go to flat tops because I was told that the domed pistons in a twin cam can cuase detonation . I thought I would keep to a bit of a milder side of things . I can always go to a .026 cometic head gasket if I need to bump it up a bit .

F.K.
Couldnt find a .026 head gast from cometic.lol

F.K.
 
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Domed pistons do not cause detonation. Don't need a .026" head gasket. A good compression target for a street build is 9.3-9.6 corrected CR and CCP at 190-195psi.

A piston with a 6cc dome at 88", 85cc chambers (no decking), .030" head gasket and SE204 cams make static about 9.5; corrected CR about 9.0 and CCP 185psi; definitely an improvement over stock.

A piston with a 6cc dome at 95", 85cc chambers, .030" head gasket and TW37 cams make static about 10.1; corrected CR about 9.4 and CCP 195psi; perfect setup for near 100HP and 110TQ.

If you have the 37 cams, you really should cut to the chase and bore to 95", use a 6cc dome piston as outlined above. If funds are not available, wait until they are. Do it once and do it right.;)
 
Domed pistons do not cause detonation. Don't need a .026" head gasket. A good compression target for a street build is 9.3-9.6 corrected CR and CCP at 190-195psi.

A piston with a 6cc dome at 88", 85cc chambers (no decking), .030" head gasket and SE204 cams make static about 9.5; corrected CR about 9.0 and CCP 185psi; definitely an improvement over stock.

A piston with a 6cc dome at 95", 85cc chambers, .030" head gasket and TW37 cams make static about 10.1; corrected CR about 9.4 and CCP 195psi; perfect setup for near 100HP and 110TQ.

If you have the 37 cams, you really should cut to the chase and bore to 95", use a 6cc dome piston as outlined above. If funds are not available, wait until they are. Do it once and do it right.;)
I talked to the guy doing my heads. We are going about 10.1:1 comp which will put it about 9.35:1 corrected and 188.9 psi, cranking comp. He is setting up the heads for the cams Andrews 37, Then the 57.
The only hold back is getting it punched to a 95 so I might have to wate till next year to get the jugs and pistons . We will see I work an extra job in the summer doing propery mataniance out on the Muskoka lakes so a bit of extra $$. Between BACA, and taking my son to Lacrosse turnaments durring the summer , I might not get at it till the fall . Just gona collect all the parts .

F.K.
 
I talked to the guy doing my heads. We are going about 10.1:1 comp which will put it about 9.35:1 corrected and 188.9 psi, cranking comp. He is setting up the heads for the cams Andrews 37, Then the 57.
The only hold back is getting it punched to a 95 so I might have to wate till next year to get the jugs and pistons . We will see I work an extra job in the summer doing propery mataniance out on the Muskoka lakes so a bit of extra $$. Between BACA, and taking my son to Lacrosse turnaments durring the summer , I might not get at it till the fall . Just gona collect all the parts .

F.K.
Domed pistons do not cause detonation. Don't need a .026" head gasket. A good compression target for a street build is 9.3-9.6 corrected CR and CCP at 190-195psi.

A piston with a 6cc dome at 88", 85cc chambers (no decking), .030" head gasket and SE204 cams make static about 9.5; corrected CR about 9.0 and CCP 185psi; definitely an improvement over stock.

A piston with a 6cc dome at 95", 85cc chambers, .030" head gasket and TW37 cams make static about 10.1; corrected CR about 9.4 and CCP 195psi; perfect setup for near 100HP and 110TQ.

If you have the 37 cams, you really should cut to the chase and bore to 95", use a 6cc dome piston as outlined above. If funds are not available, wait until they are. Do it once and do it right.;)
Well I pulled the trigger on getting my extra Jugs boared to 95. fitted pistons and rings . they should be here in two weeks along with the heads.
I'm ecited now . I thought it would be another year before I started my 95 biuld. Woot Woot.

F.K.
 
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