Hello everyone, I have a question about either installing a competition compression head or having my current head sent out and have the head shaved to accept regular gas. My engine is a 2.0 from a 72 pinto. Can I change the compressin ratio by having the head shaved? If so how much?
Thanks.
:welcome: dale the pinto man,
Shaving the head will not let you use UN-Leaded gas.
Shaving will only increase the C.R.
You need to have hardened exhaust seats installed.
NOTE: If you are not burning valves-seats already I would not worry about the unleaded gas.
From Pintony
Thanks for the reply Pintony, I,m presently using an additive with the gas, so I think I'm OK. I would like to make a little more power. Maybe the head would be a good place to start. I see where Walsh has a competitive 2.0 head for about 900 bucks. Maybe I'm approaching this the wrong way, perhaps having my head decked might accomplish nearly the same result, what do you think? I have read some of your posts and value your expertise. Thanks again.
Hello Dale,
What additives are you using?
Pulling the 2.0 head and doing some port CLEANUP. + a -.030 shave will give good results for the street.
If you plan to go racing then -.050 - -.060 may be in order.
Remember you will need an adjustable cam gear once you make the shave.
Again the exhaust seats are a good idea.
A mild cam will help out the ponys too!
AND a HEADER!
AND a free flow exhaust!
WILL THE MADNESS EVER END??? :hypno:
From Pintony
Hey Dale,
MORE MADNESS!!!
If you have any thoughts of a set of 0-DECK pistons. Forget the shave and just buy the pistons.
From Pintony
Hey guys,
Now I know why some of these Pintos drive like they were shot out of a cannon. I have a question. Pintony, If I go with the pistons do I have to pull the engine? also if a mild cam is installed will that require an engine pull? What am I getting myself into. I am lucky . however, I have a friend who is an excellent mechanic and he loves Pintos.
Dale
I forgot to mention, I'm using a leaded additive, its called CD2 a lead substitute.
Dale
to do a cam you are best to pull the head but you can check behind your radio and see if someone has cut into the fire wall to pull the cam out into the cab of the car... My 71 was don this way ... sad but true.
Frank
www.PintoWorks.com
If you have a good healthy lower end, I'd shave the head, add a mild cam and springs to go with it, and a header. A 350 Holley would also give great results. I have a 2.3 that is shaved .100 and it runs just fine on super. You'll have to use super if you shave this much. As Tony has said, you will also have to get and adjustable cam gear to correct the timing on the belt. I've built many 2.3 anyways, with many different combos, and shaving the head, has made the most amount of difference. Expect to pay around $100 or so to have that much taken off. They can only remove around 3 or 4 thoundsands per pass, so it takes awile. Good luck.
Quote from: fast34 on November 28, 2006, 07:12:42 PM
Expect to pay around $100 or so to have that much taken off. They can only remove around 3 or 4 thoundsands per pass, so it takes awile. Good luck.
UMM I'm sorry but someone has fed you a line. You can take up to around .025" to .040" per pass. You usually leave around .01 for cleanup. The reason you can do this on a head surfacing machine is that you have a cutter head thats about 13" or so in DIA and about 20 some carbide tipped cutters around the circumference . Each one is staggered in depth so that the cutting load is spread out.
To take .1 off is about 20 minutes of machine time total And thats with the "operator" or machinist doing other things in the mean time. I used to be able to surface (clean up) a set of heads in about 30 min for both. Now if they are "grinding" the head on a SURFACE grinder then that would make sense as they only can take a few thou at a time. But thats Way Over kill for an engine thats going to use a gasket.
To the point at hand id go with Pintonys suggestion about "zero deck pistons" and also Zero decking the block as well then the mill on the head wont be so severe to give a decent CR. The 71-74 blocks arent all the same that i remember. The 71 is the only year that has a zero deck to start with and stock i think its 8.6cr ( ?? ). The 72 and up had a lower CR and they did that with the block and slightly dished pistons.. I thinkit was 8.2CR. Id step up to around 9.5 to just under 10 for N/A Might get away with 10.5 with Premium fuel and your additive .Turbo is a different story ( Pintony! )
Quote from: FCANON on November 28, 2006, 06:43:07 PM
to do a cam you are best to pull the head but you can check behind your radio and see if someone has cut into the fire wall to pull the cam out into the cab of the car... My 71 was done this way ... sad but true.
Frank
www.PintoWorks.com
You have ben reading TOO much David Vizard
Quote from: dale the pinto man on November 28, 2006, 05:58:46 PM
Hey guys,
Now I know why some of these Pintos drive like they were shot out of a cannon. I have a question. Pintony, If I go with the pistons do I have to pull the engine? also if a mild cam is installed will that require an engine pull? What am I getting myself into. I am lucky . however, I have a friend who is an excellent mechanic and he loves Pintos.
Dale
YES Dale you have to pull the engine.
While it is out it is a good time to scrub-up the 30+ years of road grime and oil.
That will keep you buisy while your engine is out.
ANYWAY...
If you have an original engine that has never been bored the head shave will most likely cause you more headaches because you are asking old cylinder walls and rings to hold more compression.
Back in the day...
before I had a job still in high school
I slapped together a 2.0 with new bearings and snowcone shaped cylinder walls.
Was one of the fastest Pintos I ever built.
Maybe it was fast because mother nature was in it's advanced stages of returning it to it's origin.
HOLE-Y Pinto Batman!!!!!!
LMK if you need anymore rambling...
OH! I mean advice... ;D
From Pintony
Thanks everyone,
I do appreciate all of your thoughts. I have some thinking to do about reviving the engine.
Pulling the engine and doing it right is probably the way to go. I will keep you all informed. thanks again to 71hotrodpinto, fcanon, fast 34, and last but not least pintony. I do appreciate all your posts.
Later,
Dale
i had a '71 in '71 and it did have a flush deck. pistons right oup to the top. i remember it having a 9:1 compression ratio but that was over thirty five years ago and i think my memory might be off a bit (at least that is what my wife and daughter tell me). i had my head cut .060 then and with some valve pocket work and a header to go with a bit of rejetting the motor responds REAL well
Quote from: srt on November 29, 2006, 12:28:45 PM
i had a '71 in '71 and it did have a flush deck. pistons right oup to the top. i remember it having a 9:1 compression ratio but that was over thirty five years ago and i think my memory might be off a bit (at least that is what my wife and daughter tell me). i had my head cut .060 then and with some valve pocket work and a header to go with a bit of rejetting the motor responds REAL well
A Zero Deck 2.0 with 58cc heads wil prodice 10.4 to 1 CR.
Hmm about the stock CR. I got those numbers from two different manuals. The original ford 71 pinto manual and the chiltons. They say 71 was 8.6 and the 72 up was 8.2
Strange I thought from memory that my orginal 71 block was alot peppyer than my replacement 74 that i got as a short block. Not the differance of only .4 CR. I thought it was also 9.1 as well till i checked the book.
I ended up tossing the old head that had sunken seats and got a brand new one back in 93 then i proceeded to have it shaved " 1 compression point" as i asked Esslinger Engineering. They milled the head up to near the edge of the exhaust bolts.
I have no idea what the CR was at the time. I didnt care LOL i just wanted 200HP (which i never achieved of course)
Hey 71hotrodpinto,
The STOCK 2.0 piston @TDC is the thickness of a nickel down from the top of the block.
I was talking about zero deck pistons from Racer Walsh or Esslinger.
From Pintony
I do not try to argue with anyone, but I would never let anyone take off that much at one time off my head!! Even with a good liquid cooled grinder, heat build-up can cause warpage and a non-flat surface when done. All three shops in my area, only remove small amounts at a time, then let it set for a little while then remove more. I can't argue with them, I have done three of them with no problems. I have taken .150 off one of them and what a difference. Like I said, only if you have a healthly lower end, would this be safe to do. How much do they charge to do this in your areas??? Just like to know so I can be further educated.
8:6 or 9:0 could be. like i said it was a long time ago. one thing i DO remember, the top of the stock piston was flush with the top of the deck. the motor, to this point had never been apart and was as purchased from Downey Ford in early 1971.
Quote from: srt on November 30, 2006, 11:13:09 AM
8:6 or 9:0 could be. like i said it was a long time ago. one thing i DO remember, the top of the stock piston was flush with the top of the deck. the motor, to this point had never been apart and was as purchased from Downey Ford in early 1971.
The early 1971 Pinto 2.0 was documented as having 9to1 CR.
I have never found out what ford did to achieve the extra CR.
I always figured it was piston pin position.???
I still think that Pistons are the way to go, since most blocks need over-boreing anyway.
From Pintony
Hi Dale,
Pintony's suggestion of zero deck pistons is the way to go. Years ago (30yrs) when I first started playing with these I bought a set of pistons from Racer Walsh for about 300.00 that were advertised to be 10.5.1 CR (which they still carry), rebuilt the bottom end, and took about .010 off the head just to clean it up to make sure it was flat. Ran a Crane Cam 460 lift Apprx. 234@.050, Spearco intake, mallory dual point, 350 Holley, and Pacesetter headers w/2 1/2 in exhaust (can't believe I remember this after all these years!). The pistons when installed sat zero @ zero deck height. Anyways the cam and piston combination allowed me to use the stock springs, follwers and guides. Taking that little off the head, I didn't have to use the adjustable cam sprocket. Any more than that and you'll have to use the sprocket like Tony suggested. And by the way the combination also had plenty of valve to piston clearance and the car was quite peppy compared to stock. Hope this also may help you. We've got alot of great guys on this site. Take care and good luck. Don