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new 331 - feels like it has 100hp

  • Thread starter Thread starter sick95gt
  • Start date Start date Dec 13, 2009
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sick95gt

New Member
Sep 11, 2005
104
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Las Vegas
Dec 13, 2009
#1
  • Dec 13, 2009
  • #1
Hey eveyone, I just had a new longblock built by a local engine builder and I thought everything was going to great until I actually had it installed. He dyno's every engine he builds at the shop. When he built it, he said he had to way to dyno it with an EFI intake, so he used a carb to dyno it then put the intake on it. With the carb it dyno'd at 442 hp, which I thought would be nice. Well, when it was actually brought to the shop to swap the engine, there were a whole heap of problems. Just in case you are wondering, the engine builder only builds engines. He does not install them. So, a few problems started happening when the installers called and said the water pump wont fit because of the timing cover. Then needed a new alternator. Then needed an intake spacer because the valve covers were too tall. So, after all said and done, I drove the car home and noticed that it ran like trash. I couldn't bring it right back to the shop because I picked it up Friday right at closing, so they arent open until tomorrow. When I was driving home, my gauges didnt even work. Then when I tried to turn on my lights, they wouldnt. So, when I stopped to get get gas and check it out, the car wouldnt turn on. I had to have it jumped. The dash lights finally turned on, then started flashing bright and dim. It seemed as my alternator wasnt quite doing to job. But the car actually drove. Just horribly. So I limped home and it completely died right before I got to my street. Died to the point where it just shut off and I couldn't even roll start it by kicking it in gear. So, I had it jumped again and drove it home. I made sure connections were good and this morning, it seemed as one of the alternator plugs were loose, so I pushed it in and made sure everything was tight and started her up. The only reason she started was because I charged the battery last night. Well, I tested voltage with a DMM at idle and it was at 14.4. Turned it off and it read 12.5. Turned back on and tested at 3-4k rpm and it still tested at 14.4. Turned on lights and they worked fine and the gauges were in tact. Then I decided to take it for a drive and it ran like trash. It seriously felt like it had 100hp. I didn't immediately get on it, I let it warm up as I cruised around the block. I actually never went WOT, but even at maybe 75% throttle, there was no power. In neutral, she revs up like she wants so fast and smooth, but in gear, she just doesnt perform. I know I have to let it break in, so i didn't go crazy, but general driveability should be better than this. The shop mentioned that they put her at stock timing. I know that the builder bumped it during the dyno pulls, but I still dont think it should run this poorly. I believe at stock timing, he got almost 400hp. Now, I have stock a stock computer, and havent gotten a chip or anything. They said I don't need one and it should calibrate itself and drive fine. Are they just wrong? To give you guys the best analogy of what happens, its like a Honda that gets real loud, but doesn't move. Please let me know what you guys think.
 

fastgtfairlane

New Member
Apr 7, 2006
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Dec 13, 2009
#2
  • Dec 13, 2009
  • #2
I would start with the easy things first, check vacuum leaks, etc. If you went back to efi, you will for sure need a tune to get the car to run decent period. No way around that
 

Tanus

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Dec 11, 2009
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Dec 13, 2009
#3
  • Dec 13, 2009
  • #3
timming is probably way off, if ifs bearly advanced it will run like poop. either get a timming light and put it at like 12-14 degrees advanced, if you dont have one you can turn the distributer counterclockwise, just a hair, keep doing that till it runs strong or starts to ping, gotta be carful though, too far advanced is all bad.

ps. have a shop install a motor is a terrible idea, its a crappy job so it usually gets passed to the new guy, probably 16 17 year old that doesnt know ****. I know because I used to be that guy! haha I would trust a shop to change my oil! let alone install a motor.
 

sick95gt

New Member
Sep 11, 2005
104
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0
Las Vegas
Dec 13, 2009
#4
  • Dec 13, 2009
  • #4
Ok, I think I need to have them check the timing then. fastgtfairlane- The car is a 95 and has always been efi, but he just dyno'd the engine on the machine with a carb on it. So, do you think I need a tune either way, or will timing help?

Tanus- the only reason I brought it to this shop is because they are the dedicated shop used for the builder to install the engines. They actually primarily do swaps. The guy I had to it has been doing them for many years, but it also makes me wonder why it runs like trash. So, maybe he did it half ass. I have never done a swap before, so I don't know how much you can actually mess up by dropping in a long block that was already built except for swapping accessories. With bumping the timing, would it make that big of a difference from feeling like 100hp to actually feeling like the car should run 12's?
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,297
1,641
214
Acworth, GA
Dec 13, 2009
#5
  • Dec 13, 2009
  • #5
Definately going to need a chip.

There is a harness on the drivers side of the car right by the AC compressor that hooks the alternator up. They probably forgot to plug it back in.

Kurt
 

sick95gt

New Member
Sep 11, 2005
104
0
0
Las Vegas
Dec 13, 2009
#6
  • Dec 13, 2009
  • #6
ok then I guess I have to look at places to get a chip. Should I send it somewhere or should I take it to a local shop to have them do a dyno tune and burn a custom chip there? Also, I check the plug that connects from the alternator and runs to the drivers side and its plugged in.
 

95BlueStallion

My assy trans to myself
15 Year Member
Feb 22, 2007
5,125
3,091
214
Cedar Rapids, Iowa
Dec 13, 2009
#7
  • Dec 13, 2009
  • #7
Based on the money spent on a nice motor, I wouldnt skimp on the tune. Go have it dyno tuned, and know for sure that it is done right. If you order a mail order chip, you might get nothing out of it due to other problems.
 

Tanus

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Dec 11, 2009
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#8
  • Dec 13, 2009
  • #8
sick95gt said:
Tanus- the only reason I brought it to this shop is because they are the dedicated shop used for the builder to install the engines. They actually primarily do swaps. The guy I had to it has been doing them for many years, but it also makes me wonder why it runs like trash. So, maybe he did it half ass. I have never done a swap before, so I don't know how much you can actually mess up by dropping in a long block that was already built except for swapping accessories. With bumping the timing, would it make that big of a difference from feeling like 100hp to actually feeling like the car should run 12's?
Click to expand...
difference between 6 degrees and 14 (mine actually runs best at 16, no ping either)is HUGE!!!

If you get a clichton manual and take your time you'd be amazed how simple putting a car together is, hardest part is what your doing now, getting everything to run good. also once you go through a couple heat cycles you HAVE to go retighten just about every bolt(not any of the internals)which a shop wont do and you'll blew a header gasket in a month, I guarantee

problem with shops is the guy working just want to finish the job as fast as possible, as long as it can drive out the shop, he's done. Maybe he's haveing a bad day, maybe pissed off that you have a nice car and he doesnt, got high at lunch and ended up with a few extra bolts, haha. any number of things can cause him to half-ass it. Trust me, cause Ive been that guy before. The shop I worked at didnt even ask if I knew what I was doing, just said "hey, go pull that motor" haha



chip definatly will help, but I dont think its mandatory(at least not on computer on fox's, 94-95 may have different computers,IDK. My stang runs low12s(holley heads/intake and the biggest ford racing cam, the Z303) mine idles like a stock car and pulls smooth all the way to 6,500 even hit 7G's a few times, according to the stock tachometer.no chips or dyno sessions, just tuned by feel.
 

sick95gt

New Member
Sep 11, 2005
104
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0
Las Vegas
Dec 13, 2009
#9
  • Dec 13, 2009
  • #9
Im gonna try the timing. I;m just so skeptical since it performs so much more poorly than stock. It idles great and revs up fine, but under load, just doesnt feel like going anywhere. What startles me is that it revs up like a beast and so fast, but wont put any power to the ground....
 

Tanus

New Member
Dec 11, 2009
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Dec 13, 2009
#10
  • Dec 13, 2009
  • #10
yeah thats a bad sign, usually it will rev real slow if the timings off. Id pull the plugs and see if your running too rich or too lean.

dont accelerate too hard on that fresh motor, you want to get high in the rpms, but get there slowly.
 

4Jenna

Founding Member
Sep 12, 2001
4,326
6
69
AZ
Dec 14, 2009
#11
  • Dec 14, 2009
  • #11
How do the plugs look?
 
9

95_5.0@15

New Member
Jul 21, 2008
24
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0
Dec 14, 2009
#12
  • Dec 14, 2009
  • #12
Im interested in seeing what the hell is goin on... you sure they didnt give you 2 four cylinders? j/k
 

Black Stampede

Founding Member
Sep 3, 2002
1,811
2
39
Grand Rapids, MI
Dec 14, 2009
#13
  • Dec 14, 2009
  • #13
Dyno tune with custom chip.
 

Adam95GT

New Member
Aug 14, 2006
2,564
3
0
Burlington, NJ
Dec 15, 2009
#14
  • Dec 15, 2009
  • #14
get a tune....

but first take it back to who put it in and make them fix your charging issues
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Dec 15, 2009
#15
  • Dec 15, 2009
  • #15
I skimmed over this thread kinda quickly

It looks like it all boils down to peeps working on your Stang and not doing
work like it should be done

Man O Man ... it could be a bunch of different things

Is there anyone who is responsible for the total work of installing the motor in the car

If so ... I'd get with them and address all the issues

Yes ... you can check this and that
but
You also paid somebody to do that :Word:

Its most likely gonna be a bunch of little stuff

Grady
 

LethalInjection

Founding Member
Jul 26, 2002
217
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17
Arkansas
Dec 15, 2009
#16
  • Dec 15, 2009
  • #16
It doesn't sound like the engine is at fault. It sounds more like a bad install. Check firing order, all vacuum lines, and test the whole intake system from maf to heads for proper seal to make sure there is no vacuum leaks there. After that, I would put a timing light on it and make sure it's at 10 degrees base. Do what the guys above said and check the plugs. Could you list ALL the mods (assuming they are different than your sig)? I'm curious as to what fuel injectors, maf, etc that it has.
 

Pokageek

Active Member
Jun 10, 2005
2,767
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46
MA, USA
Dec 17, 2009
#17
  • Dec 17, 2009
  • #17
This happened to me. MAF was suposed to be tuned for 24# inj and still didnt work right (306). Ran like crap. When I first put in my 414 in it wouldnt even break the tires loose and dyno'd at a miserable 300rwhp without a tune. Don't be discouraged..well do.. and then make it better. The builders /tuners dumping it on you are a bunch of A holes and you should get your money back.
 
S

sgarrelts01

New Member
Apr 26, 2009
133
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Niles, Michigan
Dec 17, 2009
#18
  • Dec 17, 2009
  • #18
this is a broad answer, but make a list of possibilities, check them all. Process of elimination. Or just start from the most common to the most extreme.
 

629RWHPstang

New Member
Apr 28, 2009
19
0
1
NY
Dec 17, 2009
#19
  • Dec 17, 2009
  • #19
dude your mass air is prob calerbated to 19lba injectors or something
 

sick95gt

New Member
Sep 11, 2005
104
0
0
Las Vegas
Dec 18, 2009
#20
  • Dec 18, 2009
  • #20
Hmm, is there a way to check if the MAF is miscalibrated? Plugs look good, but not sure if the firing order is correct. Is the firing order the same on all the years, or is it based on my year computer, or the year of the block etc?
Lethalinjection- the mods in the sig are current. It has 24# injectors, C&L MAF that is supposedly calibrated for 24# injectors, but based on what people are saying here, it might not be.
I brought is back down to the shop and they are going to look at it and check for leaks and stuff and check the timing and bump it and make sure it doesnt ping. He said he is going to road rest it until it runs right. I can't expect it to be 100% but I can expect it not to run like *****. I am going to take it to the speedway and get a dynotune afterwards if he can get it running decent. If not, I need to try to address all of these areas.
 
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