Larger exhaust valves

[LameHoof65]

I have the stock valve set from FSPP but now I am wondering if I should have gotten the performance set? I know, I should have thought this through better.....but with time and a little more thought, well you know...Will it make that much difference in flow on a D7. I have the big holley 2v, I have ported the head some. I am also thinking of bringing the CC down to 43cc's with about .016 piston to deck clearance, with the regular corteco gasket it will put my compression in the 10:1 range...I am just wondering if I should try that much for a streetable ride?

 

[rbohm]

8) a larger exhaust valve will help, and any help you can give these sixes in breathing is always good. as for the 10:1 compression, that might be a bit much for a street engine. try i though and see how it goes. you can always install a thicker head gasket if needed.

 

[LameHoof65]

I decided to go ahead and order the performance valves from Mike. I called NAPA and they located me a set of intake valves for a 144 but at $10.50 a pop and that didn't include shipping. So, I went for Mike's deal and just got a complete Si valve setup. I will use the stock setup on another head and build it up for a more economical ride if I ever need it.
When Mike gets the .038 gasket I will get it as well...right now I guess I will play it safe and only go for about 50cc's, using Dennis' calculator that will put me at 9:1 with the .053 head gasket and with the the .038 closer to 9.3:1. If I don't like the performance there, I will just pull the head and take it in and have a little more shave off.

 

[LameHoof65]

Took, my head in today...a place here that i knew would cost a bit...but the guy knows his stuff...I was referred by two different machinist. I ported it as much as possible without going overboard. I opened up the log for the 2v and he is going to machine enough off for 9.1-1 for the .053 gasket and if I decide to go the .038 Mike is looking into I will get 9.3-1. I am also opening up and installing hardened seats on the exhaust for the Si valves. He said opening up would leave a lip and wanted to know if I wanted to port it out to save a little money, I said heck no! I have done all the die grinding on that thing I am going to do...He said he would do the 3 angle backcut and back cut the intakes if I wanted..He is not backcutting the exhaust valves. Total---ready for this---somewhere around $560.00 smackers...I just got tired of shopping for a deal and this guy is suppose to be really good...Oh, yea he said he would install the teflon seals. When I asked how long I would have to wait he said "two weeks, this is what we do, build performance engines---we stay on top of our stuff---no three month wait here!" Guess, we'll see, huh?

 

[kirkallen143]

Took, my head in today...a place here that i knew would cost a bit...but the guy knows his stuff...I was referred by two different machinist. I ported it as much as possible without going overboard. I opened up the log for the 2v and he is going to machine enough off for 9.1-1 for the .053 gasket and if I decide to go the .038 Mike is looking into I will get 9.3-1. I am also opening up and installing hardened seats on the exhaust for the Si valves. He said opening up would leave a lip and wanted to know if I wanted to port it out to save a little money, I said heck no! I have done all the die grinding on that thing I am going to do...He said he would do the 3 angle backcut and back cut the intakes if I wanted..He is not backcutting the exhaust valves. Total---ready for this---somewhere around $560.00 smackers...I just got tired of shopping for a deal and this guy is suppose to be really good...Oh, yea he said he would install the teflon seals. When I asked how long I would have to wait he said "two weeks, this is what we do, build performance engines---we stay on top of our stuff---no three month wait here!" Guess, we'll see, huh?

Same specs as your head and my total price 5 months ago was $480.00.
Time it took to get the job done...5 1/2 months.
Patience has it's virtues, but it does suck to have to wait.

Kirk

 

[Mustang Boy]

dang guys i had the larger SI vlavles installed in my head and these were valves were biger than stok so theyahd to make the valve hole thing bigger i also had the head milled down 2angle job on both intake and exhaust and the new springs out on for like $275 and since the machine shop had no other nusiness that day it was finished the same day

 

[LameHoof65]

You are fortunate, I just decided that I couldn't wait for a the ideal situation any longer. I also, ran into some odd characters who claimed to be able to do what they actually couldn't. This guy knew the last machinist I had gone to and both come from racing families. But the previous fella's health was not good and just couldn't get it done. I feel real confident with this guy and his history---well known by racers here in OK. He calls when he has questions or concerns and I definitely like that little bit of consideration. You know what they say about folk who---assume. I am glad you got the deal you got MustangBoy,but I am sure that KirkAllen143 has gotten a few good deals elsewhere just as I certainly have. All and all it probably all evens out to a few dollars and cents in the end.

 

[Nathan289]

Arent the new SI Valves already back cut? well the intakes are arent they?
Nathan