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Engine 89- rebuilt motor and its a slug

  • Thread starter Thread starter Wonderbread750
  • Start date Start date Apr 22, 2018
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    engine rebuild
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Noobz347

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#21
  • Apr 25, 2018
  • #21
Wonderbread750 said:
Got it ill throw a bigger pump on it and see what happens
Click to expand...
Get a bigger pump and get it to a tuner.


or blow it up...

Get some video either way.

The stock ECU was never designed to enrich fuel under boosted conditions. It has no way of knowing that it's two or more bars over ambient air.
 
W

Wonderbread750

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Apr 24, 2014
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#22
  • Apr 25, 2018
  • #22
Noobz347 said:
Get a bigger pump and get it to a tuner.


or blow it up...

Get some video either way.

The stock ECU was never designed to enrich fuel under boosted conditions. It has no way of knowing that it's two or more bars over ambient air.
Click to expand...
Will do, that’s exactly what a91what told me, it needs a computer, Then all problems should hopefully go away, now i just need to find a computer any suggestions for me to compare?
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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Apr 25, 2018
#23
  • Apr 25, 2018
  • #23
Wonderbread750 said:
Will do, that’s exactly what a91what told me, it needs a computer, Then all problems should hopefully go away, now i just need to find a computer any suggestions for me to compare?
Click to expand...

If you are going to self-tune then a91 would be a good guy to try and work that out with. If you're going to have it tuned, use whatever the tuner suggests and is familiar with.
 

CarMichael Angelo

my rearend will smell so minty fresh,
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Apr 29, 2018
#24
  • Apr 29, 2018
  • #24
So,.......
You have a stock block, stock internals, Stuck induction, stock head, twin turbo build that you just happen to remember that you also have added?

There is so much wrong here that I don't know where to start.

Define "slug".

You are now pumping your N/A exhaust through a tiny little turbine hole comparably speaking...you no longer have an optimized N/A setup, I'd imagine If I added a restriction to my exhaust, the car would run poorer just because of it. Ever watched vids of how hot a turbo gets?.....It didn't do that because its free flowing....

As long as you lined up the cam and crank dots properly, the engine will run fine. Degreeing a cam doesn't necessarily change anything to that relationship, it just confirms that it's right. The fact that you may have a cam with a higher power band won't make it a slug, it just changes where the full power is realized. In this case, that means that lower end RPM suffers, but anything after 2500 RPM is in the power band....Again,....NOT the reason the car is slow.

Do you have a reference point for how the car ran before you decided to go this route? When it's running and being a "slug", does it still run right? (i.e. no bucking, no stalling, no RPM break up?)

What ring did you use? I'm thinking an OTS set that you didn't gap. And that are now on a set of stock hyper-eutectic pistons.

When you start making boost, the associated heat from that causes the ring end gaps to close. If there isn't sufficient gap, the rings fail. They typically will butt together, and seize in the land, or potentially cut off the top ring land.

What are the two turbo's that are now on this engine? what waste gates are you using? What are you doing to control Blow off?

How much experience do you have with just getting an engine to run good? I mean forget the turbos, forget changing out the Cam, the ECU and the freaking fuel pump for now, forget the pushrods......How much experience do you have with just getting a F.I. engine to run right?

Just from what I'm reading, you are heading straight down a path towards catastrophic engine failure when/if you get to the point of making boost.

And don't listen to guys that tell you to change out junk before they ask a single freakin question.

I'm curious as to what your answers are to my questions.
 
Last edited: Apr 29, 2018
W

Wonderbread750

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Apr 24, 2014
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May 17, 2018
#25
  • May 17, 2018
  • #25
CarMichael Angelo said:
So,.......
You have a stock block, stock internals, Stuck induction, stock head, twin turbo build that you just happen to remember that you also have added?

There is so much wrong here that I don't know where to start.

Define "slug".

You are now pumping your N/A exhaust through a tiny little turbine hole comparably speaking...you no longer have an optimized N/A setup, I'd imagine If I added a restriction to my exhaust, the car would run poorer just because of it. Ever watched vids of how hot a turbo gets?.....It didn't do that because its free flowing....

As long as you lined up the cam and crank dots properly, the engine will run fine. Degreeing a cam doesn't necessarily change anything to that relationship, it just confirms that it's right. The fact that you may have a cam with a higher power band won't make it a slug, it just changes where the full power is realized. In this case, that means that lower end RPM suffers, but anything after 2500 RPM is in the power band....Again,....NOT the reason the car is slow.

Do you have a reference point for how the car ran before you decided to go this route? When it's running and being a "slug", does it still run right? (i.e. no bucking, no stalling, no RPM break up?)

What ring did you use? I'm thinking an OTS set that you didn't gap. And that are now on a set of stock hyper-eutectic pistons.

When you start making boost, the associated heat from that causes the ring end gaps to close. If there isn't sufficient gap, the rings fail. They typically will butt together, and seize in the land, or potentially cut off the top ring land.

What are the two turbo's that are now on this engine? what waste gates are you using? What are you doing to control Blow off?

How much experience do you have with just getting an engine to run good? I mean forget the turbos, forget changing out the Cam, the ECU and the freaking fuel pump for now, forget the pushrods......How much experience do you have with just getting a F.I. engine to run right?

Just from what I'm reading, you are heading straight down a path towards catastrophic engine failure when/if you get to the point of making boost.

And don't listen to guys that tell you to change out junk before they ask a single freakin question.

I'm curious as to what your answers are to my questions.
Click to expand...

No your right, this is my first build its total trial and error here, im going to build a 351cleveland up after i learn some stuff, the 302 is just my project to learn from i didnt know about piston ring gap with the heat of the boost you got me with that, i specced them to the chilton book, i have forged internals, and the engine i built ran great before i started the twin project, It was sluggish til the power band but not that bad, but now with the 2lbs of boost that actually hit the motor it leans out like the sensors are not taking it nicely, before the twins it never leaned out. Could the stock fuel rails with the 49 lb injectors be the problem for the leaning out? The motor ran great before the 2lbs of boost hit the motor, i have two blow of valves located om the intake side right past the turbos and an intercooler
 
W

Wonderbread750

Member
Apr 24, 2014
70
0
7
May 17, 2018
#26
  • May 17, 2018
  • #26
Noobz347 said:
Get a bigger pump and get it to a tuner.


or blow it up...

Get some video either way.

The stock ECU was never designed to enrich fuel under boosted conditions. It has no way of knowing that it's two or more bars over ambient air.
Click to expand...
What tells the ecu about the temperature??
 
W

Wonderbread750

Member
Apr 24, 2014
70
0
7
May 20, 2018
#27
  • May 20, 2018
  • #27
Faulty computer chip. Problem solved took it off and bam all the fuel issues went away
 
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