My engine rebuild thread!

[ttocs]

I’ve got the 42’s

are you going to get another tune done or use a calibrated maf?

 

[Daryl]

For now, leaving it as is

 

[Daryl]

Daryl, can you post the dyno sheet?

And if I can ask, what fuel pump, what maf, injectors and throttle body?

Best I know, it’s the stock fuel pump; new 42# injectors; BBK 75mm throttle body

 

[Daryl]

are you going to get another tune done or use a calibrated maf?

Would I need another tune? Thought that was the final tune.

 

[Daryl]

Daryl, can you post the dyno sheet?

And if I can ask, what fuel pump, what maf, injectors and throttle body?

Sorry, here’s a couple of pics of the dyno sheet...

 

[lwarrior1016]

If it is as tuned with the 42’s then you are fine. I believe Scott is thinking you were swapping injectors. If you change them, you have to get a new tune.

 

[Daryl]

Best I know, it’s the stock fuel pump; new 42# injectors; BBK 75mm throttle body

 

[ttocs]

I did think we were going from 24 to 42 lb injectors.

 

[Wmac]

I would think that with the heads, cubes & cam, that it should make big power numbers right up to 5500. Yet seems to hit a brick wall around 4500.
Any dyno experts have an opinion?

 

[Daryl]

I would think that with the heads, cubes & cam, that it should make big power numbers right up to 5500. Yet seems to hit a brick wall around 4500.
Any dyno experts have an opinion?

FTK said the cats are just choking the hell out of it. He ran them til they were red hot and that’s all he could get out of it.
I was expecting bigger numbers, too. Somewhere in the 350hp range, especially with the rebuild and having 347cubic inches. So yes, I’m disappointed but on the plus side... it’s fun as hell to drive and I’m really glad I got the 3.55 gears instead of the stock gears.

 

[ttocs]

how old are the cats? They could be clogged up and need replacing.

 

[Daryl]

They’re brand new. Had all 4 replaced so I could pass smog test if/when required.

 

[ttocs]

are they stock or high flow cats? I just can't believe that they are choking it down that much.

 

[Daryl]

High flow. But there’s 4 of them! Eek!

 

[TrickVert]

I'm tellin' you, it's *not* the cats, especially if they're new hi-flow parts. The stock fuel pump could be a limiting factor, but the tuner should have seen things going lean. The same if the 24's were inadequate (they shouldn't be).

 

[Daryl]

I’ll shoot them an email and rattle their cage about it again.

 

[ttocs]

Just keep it simple and ask them if they thought the power/torq was where it should be? I have to agree if it was fuel they should have been able to tell you and high flow cats should not choke it down that much. Of course you can always slap an offroad pipe on it and test their theory. We could start a mission to smuggle you one in....

 

[Daryl]

Ok, I just sent FTK an email stating the following:
1. A new 1995 SVT Cobra had 240hp with 4 cats.My rebuilt, 347 stroker has 202hp. How’s that possible? The 165 heads? The stock fuel pump?
2. It has a BBK 75mm throttle body, new 42lb injectors, CAI, 4 new hi-flow cats, a thumping cam and new MAF sensor. New plugs, wires and distributor. Where did we miss the boat???

 

[TrickVert]

Waitaminute.... If "He ran them til they were red hot...."???

 

[ttocs]

well that could be as simple as a timing problem or idunno.