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Mach 1 short block

  • Thread starter Thread starter Stumbaugh
  • Start date Start date Sep 14, 2010

Stumbaugh

Member
May 13, 2010
903
13
19
Russellville, Ar
Sep 14, 2010
#1
  • Sep 14, 2010
  • #1
A friend of mine has an 03 Mach 1 5 speed car. Well he has finished up his teksid 5.1 stroker build for his car. I was asking him what his plans were for his stock short block, he said he planned on selling it to me. lol. Well, I am interested in this motor because mine has 142,000 miles on it and I have been spraying it for the past few miles or so.

Here's my question, would this motor make anymore compression than my stock 4.6 does? I am looking at keeping this a N/A-No2 car for now, so the more compression the better. I know the cranks in those motors are good, what about the rods and pistons? Just any info on those motors would be helpful.
 
N

ninjastang125

New Member
Nov 1, 2008
591
2
0
maryland
Sep 14, 2010
#2
  • Sep 14, 2010
  • #2
Yes it will bump the compression. The rods are powdered and pistons are hyperjunk...
 

DOHC otto

Member
Oct 10, 2007
139
0
16
Rock Island, TN
Sep 14, 2010
#3
  • Sep 14, 2010
  • #3
Stock Mach compression is 10.1:1 so it will be more than your stock compression. If it was an 5 speed it has forged kellogg crank, rods are pistons aren't forged but are good for around a 150 shot.
 

Stumbaugh

Member
May 13, 2010
903
13
19
Russellville, Ar
Sep 14, 2010
#4
  • Sep 14, 2010
  • #4
I knew the Mach's had higher compression than the regular 4.6's, but I wasnt sure what the cc difference was in the cylinder heads. I am really hoping to be able to achieve somewhere around a 10:5 compression.
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Sep 14, 2010
#5
  • Sep 14, 2010
  • #5
The stock PI piston has a 17cc dish and the chamber is 42cc giving a 9.7:1 compression ratio. If you put a 42cc PI head on a Mach shortblock which has a very small piston dish (3cc) you'll end up with a very high compression ratio of about 12:1.

It's going to require a good tune to stave off detonation on pump gas with a 2V head at that compression ratio...
 

nickmckinney

Member
Sep 25, 2009
164
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16
Sep 15, 2010
#6
  • Sep 15, 2010
  • #6
Notch the pistons, install a real cam, there is a replacement forged rod that doesn't change the balance on the crank that much you can swap in as well. Then you would have a killer 2V.
 

Stumbaugh

Member
May 13, 2010
903
13
19
Russellville, Ar
Sep 15, 2010
#7
  • Sep 15, 2010
  • #7
nickmckinney said:
Notch the pistons, install a real cam, there is a replacement forged rod that doesn't change the balance on the crank that much you can swap in as well. Then you would have a killer 2V.
Click to expand...

That's pretty much my game plan. I might have to talk to you about the cam set up, I am looking at turning some RPM's on spray. I am wanting to spin the motor high enough to put good use to a Victor Jr intake...
 

GoBabyVroommm

Active Member
Mar 22, 2003
1,156
0
36
Chicago, For Realss???!!!
Sep 15, 2010
#8
  • Sep 15, 2010
  • #8
Good luck with it but on a 150 shot i riped the rod from the piston on my 99 4v. IMO if your at the short block get some new rods and pistons.
 

nickmckinney

Member
Sep 25, 2009
164
0
16
Sep 15, 2010
#9
  • Sep 15, 2010
  • #9
Stumbaugh said:
That's pretty much my game plan. I might have to talk to you about the cam set up, I am looking at turning some RPM's on spray. I am wanting to spin the motor high enough to put good use to a Victor Jr intake...
Click to expand...


If you are going to spray and the bores are good you need to get a forged piston as well. Manley and Icon have them in the stock bore size for a reasonable price and lighter weight as well.
 
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