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Lack Of Power On 331

  • Thread starter Thread starter John Grunwald
  • Start date Start date Jul 13, 2013
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iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jul 15, 2013
#21
  • Jul 15, 2013
  • #21
John Grunwald said:
Well I'll be runnin it at Irwindale this Thursday I'll post what my times are,
Click to expand...
I usually go a couple times a month, but im leaving for Pismo for a week so im still getting things ready.

Good luck and dont expect much on your first few runs.
 
J

John Grunwald

Member
Jan 19, 2012
38
0
7
Jul 16, 2013
#22
  • Jul 16, 2013
  • #22
Hey iskwezm are you running a stock block or aftermarket? I read your build and I was looking into adding like 7 lbs to my motor because my compression is pretty high but I'm scared that my block will split
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jul 16, 2013
#23
  • Jul 16, 2013
  • #23
John Grunwald said:
Hey iskwezm are you running a stock block or aftermarket? I read your build and I was looking into adding like 7 lbs to my motor because my compression is pretty high but I'm scared that my block will split
Click to expand...
I have a stock block and about 8.7:1.A block can split at anytime and there is no magical number.I have mine detuned to help avoid that.But i have freinds that are making 550 hp and it last for years and others making 450 hp that last a few trips to the strip.A main girdle just helps in keeping the parts in a pile if the block does split. They also make a valley girdle, but havent seen that be the end all fix yet.I have run up to 15 psi on my block but keep it at about 10psi now.
 
J

John Grunwald

Member
Jan 19, 2012
38
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Jul 17, 2013
#24
  • Jul 17, 2013
  • #24
Oh ok thanks! And also how long will a stock c4 last with a 400 hp+ motor? Ive read only 350hp then I've seen 550hp, anyone know? My trans has a 3200 stall, external cooler, and band transpack
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Jul 17, 2013
#25
  • Jul 17, 2013
  • #25
Depends on the valvebody and line pressure. Did you put a gauge to check pressure?
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jul 17, 2013
#26
  • Jul 17, 2013
  • #26
When i rebuilt my c4, i added a couple more clutches,76' Mustang II converter(2800 stall) and raised the line pressure.I used that trans with nitrous for years and then sold it to a friend, so now its about 15+years old and he's using behind a 347 stroker.
 

clement

Founding Member
Feb 27, 2001
1,106
52
59
Oak Cliff
Jul 17, 2013
#27
  • Jul 17, 2013
  • #27
right now my c4 has stock everything except the valvebody and converter and its running 6.30s@107 in the 1/8th in a 3000lb car. its been together for 3 years without a freshening all three years running mid 6s in the 1/8th. so 400 hp shouldn't be an issue.
 
J

John Grunwald

Member
Jan 19, 2012
38
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7
Jul 17, 2013
#28
  • Jul 17, 2013
  • #28
What's a good valve body for a c4? I have a b and m transpack but I'm not to impressed
 

clement

Founding Member
Feb 27, 2001
1,106
52
59
Oak Cliff
Jul 17, 2013
#29
  • Jul 17, 2013
  • #29
I love my broader performance pro tree transbrake vb.

http://www.broaderperformance.com/ford-c4/38-c4-pr-tree-transbrake-valve-body.html
 

blown65

Founding Member
Jul 7, 1999
1,938
4
39
Queen Creek Arizona
Jul 17, 2013
#30
  • Jul 17, 2013
  • #30
PA Automatics are good, at least my complete one was so I'd assume their valve bodies are good also. Had tons of passes low 10's high 9's and several low 9's and never had it apart. 2-3 shift was starting to get strained by my 1000hp so I sold it to a friend for his 600hp deal and back to shifting perfect again.

I know 600hp deals they will last a long ass time if done right.
 
J

John Grunwald

Member
Jan 19, 2012
38
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Jul 18, 2013
#31
  • Jul 18, 2013
  • #31
well I was looking over my car before I headed over to irwindale and noticed that I have a lot of dent marks where my drive shaft meets the rear end. I checked to make sure all the Ubolts and driveshaft bolts were tight. Everything checked ok. I have noticed that in the past few days my upper end power is a lot stronger but my low end felt a little sluggish and I kept hearing a banging/grinding noise from the rear. This was after taking everyones advice and changing the timing and fueling a tad. So ive came to the conclusion that I fixed the lack of power but now im going to need a set of traction bars hahahaha. But ya im getting quite a bit of wheel hop and loss of traction, the rear reaaaally has to be twisting hard to bring the snout of the rear end that high into the tunnel wall. You guys think I should run it tonight or will I snap something hahaha? and also is there really a big difference between some cheaper slapper bars and caltracs? I know im going to need new springs and traction bars soon but I don't really feel like dropping 340$ on caltracs, thanks for the help guys!!
 

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iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jul 18, 2013
#32
  • Jul 18, 2013
  • #32
how low is your car? Is your pinion angle set correctly??

And there is a big difference in Caltracs and slapper bars. They both work, but one works better.
 
J

John Grunwald

Member
Jan 19, 2012
38
0
7
Jul 19, 2013
#33
  • Jul 19, 2013
  • #33
So I got back and my best time was 8.4 @ 81.38 I only got 2 runs and this was my first time on the strip ever, the 60 ft was 1.889 so I didn't to bad with stock suspension and a ton of wheel hop but the only issue was on the 3rd run I blew the tranny... 3rd gear is gon, I was planning on rebuilding it soon enough but does anyone know a good performance rebuild kit that will last 500+ hp?
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Jul 19, 2013
#34
  • Jul 19, 2013
  • #34
Check out broader performance. There is a link above. I used a lot of their parts in mine and it is hanging in at over 650rwhp...knock on wood.
 
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