what to do?

[1967JMG]

Hey guys,
I have a what is pretty much completely stock, re-manufactured 200 with about 8k miles on it. I'm getting real tired of everybody telling me to get a v8 because there are more performance option for them and things of that sort. So, I've been looking at getting the aluminum head. The porting options have me a little thrown. I'm not exactly which set i want, either boosted(about 7lbs) or N/A. With the boosted set up I'm pretty sure a C/R of roughly 8.2:1 would be okay (I'm pretty sure that is stock for most 200's too. please correct me if I'm wrong). With the N/A I would want to go with about 9.5:1. I will probably be going with a 274-110 cam 1.6 roller tipped rockers and 302 springs.

What would be the proper porting option to go with as far as cc & mill, then deck height, and ect to achieve those C/R numbers?

Oh, and also, this is my primary vehicle. So, would going boosted be a bad idea? I definitely need to maintain drivability to and from work and home. I just want to have more fun driving there. Plus there is always the occasional trip to the track to have a bit more controlled fun.

Thanks alot guys!
-Julian

 

[Ronbo]

"I'm getting real tired of everybody telling me to get a v8 because"

Tell them to move on. 8) I put a single in dual out muffler giving the dual exhaust appearance. That stops about 95% of the chuckle heads but you alwas have the one or two normally silent folks that pop up and announce its a six! They see the four lugs.

Somebody will chime in shortly about what options to go with. Being in Florida do you have AC in the car? How about power brakes? Those probably will be factors in cam selection.

Ron

 

[shmoozo]

... I will probably be going with a 274-110 cam ...

That's likely going to give you a "lopey" idle, may reduce your low RPM torque, and could lower your vacuum to where it will be just barely enough for power brakes. You'll probably also take a bit of a hit at the gas pump. If you can live with that as the trade off for more power, fine, but be sure to talk to some cam selection experts before finalizing that choice. I might suggest a slightly wider separation angle if this is going to be your daily driver, perhaps 112 degrees or so, with the idea being to smooth up the idle, improve your vacuum. improve your low ROM torque, and reduce fuel consumption, but the experts might tell you that you'll be fine with the one you have selected. Listen to the experts, not me.



By the way, one of the most commonly given pieces of performance cam selection advice I have seen over the years is pick out the cam you think would be good, then go with a grind that is "one notch milder" than that. The old sages say you'll be happier in the end if you do.

 

['68falconohio]

I've always wondered about this on the cams that decrease vacuum. I thought I saw on one of the generic 'hot rod' shows where they used a vacuum reservoir to account for the lack of adequate vacuum at low rpm. Why worry greatly about this if you can easily fix it with a vacuum reservoir, or does it not work?

Stephen

 

[mach1 mark]

My question would be what kind of Carb are you going with. maybe you've already said, but a more performance cam has to have a better carb. With the new aluminum head I'd go with the Holly or autolite 4 barrel. I have a 272 cam with a holly 500 cfm. Its a little lopy, has little vacuum, but ideals OK. I put it in neutral (c4) at stop lights. Oh and with the headers and duel exhaust people think its a 302. I'm so proud of it I lift the hood to show off my in-line. I get a few Oh's just a six, but then I ask them what they drive? :mrgreen:

 

[1967JMG]

I plan on going with a 500 or 600cfm carb. 600 if that's not too big.
How much does it cost and how long does it take on average to get the block zero decked?
Im still not sure what mill & cc to go with. There are soo many options... I was thinking about just getting the 56cc since that comes standard and get it milled later... the only problem there is finding the time to do it, since i would be so excited to put it on.
Like i said, this is my primary vehicle so I cant afford alot of down time.

 

[rocklord]

1967JMG,

With a combustion chamber of 56cc, in order to obtain a 9.5:1 compression ratio you would have to do the following:

- Zero deck the block
- Use flat top pistons
- Use a head gasket with the thinnest compressed thickness (0.044 inches)

There are compression ratio calculators out on the web, but some don't take into account the diameter/volume of the head gasket cylinder hole (most of ours is 3.71 inches).

I made my own CR calculator in Microsoft Excel to do the what ifs. My head has a 58cc combustion chamber, so just to get to a 9.41:1 CR
I would have to do the following:

- Zero deck the block
- Use +0.030 flat top pistons (3.71 inches)
- Use a head gasket with the 0.044 compressed thickness

If I use a head gasket with a 0.053 compressed thickness, It drops to 9.22:1

I was talking to Mike of CI asking him some of the same questions you've brought up. He said what a lot of other people have told me: figure out what you want, then plan out how to get there. It's awful hard to put metal back onto a block or head if you miscalculate the CR.

 

[shmoozo]

... I will probably be going with a 274-110 cam ...

That's likely going to give you a "lopey" idle, may reduce your low RPM torque, and could lower your vacuum to where it will be just barely enough for power brakes. You'll probably also take a bit of a hit at the gas pump. If you can live with that as the trade off for more power, fine, but be sure to talk to some cam selection experts before finalizing that choice. I might suggest a slightly wider separation angle if this is going to be your daily driver, perhaps 112 degrees or so, with the idea being to smooth up the idle, improve your vacuum. improve your low RPM torque, and reduce fuel consumption, but the experts might tell you that you'll be fine with the one you have selected. Listen to the experts, not me.



By the way, one of the most commonly given pieces of performance cam selection advice I have seen over the years is pick out the cam you think would be good, then go with a grind that is "one notch milder" than that. The old sages say you'll be happier in the end if you do.

 

[mach1 mark]

I run a 500 cfm Holly on an Aussie head, I had to tweak the carb to get it to run right. (once you get the whole set up, buy a carb book and read it, even if its just on Hollys). I bought a four barrel Autolite with a 1.12 venture. The dyno test Mike did was with the new head, 4 barrel intake, and a Pony carb Autolite. The carb from Pony is acutely a 1.12 venture with a 1.08 sleeve installed. Its supposed to run great. That's why I bought the 1.12 (there cheaper also). The 1.12 has 600 cfm and the 1.08 has 480. Anyway what I'm trying to say is that it really depends on the carb whether you go with 600 or 500 cfm. You will find discussions in the forum that the 500 is way to big, but I've tried the Autolite two barrel, car runs smooth but doesn't have the punch like the Holly 500. And of course after shooting my mouth off about how great the Autolite 480 cfm or the 600 cfm I haven't put the Autolite 600 cfm with the 1.12 venture on yet because it needs an adapter to go on the Aussie head. I'll get to it and what I've read I think it will be great. Buy the four barrel intake from Mike, even if you decide to go with the two barrel you can adapt easier from a four to a two rather then try to get a 4 on a 2v intake. I hope this wasn't to confusing.

About the milling of the block, I had mine bored and balanced, it took about two weeks. But just to shave the block it should be done right away. Go ahead and have them cut rings in it, sense you've got it there, you might want to go turbo or supercharger later. Shave the block to zero, you can always make up for it with these new gaskets. I had an OEM gasket so I came pretty close to zero.

Good luck and keep us informed.

 

[1967JMG]

Thanks for all the help, ideas, and advice you guys. I have just about all my money saved and I want to make sure that I do this right. I'd rather do it slow and right than get it done fast and have a boat load of problems in store for myself in the future.

-JMG

 

[mach1 mark]

Take your time, we'll be here By the way, great looking stang, Lets see some photos!

 

[1967JMG]

Take your time, we'll be here By the way, great looking stang, Lets see some photos!

sure thing. I'll post some as soon as i figure out how!

 

[drag-200stang]

If you plan on boosting it, only deck the block the minimum amount to make it flat. The 200 deck is fairly thin when it comes to boosted motors. If you have to have 0 deck, figure out some other way. Offset ground crank. Bushed rods to make them longer. Taller piston, etc.