[JLMounce]

OKay, I took your original post about using mixture for e85 as to mean you had also commanded a richer mixture on top of your additional displacement. Yes you want to view your afr's as though you were using gasoline.

Specifically with the e85 deal, you need to be in a habit of running datalogs, specifically to view the fuel trims. 30% increase in displacement is a very rough number and may end up being wildly inaccurate depending on your specific combination. You stated it's running a bit on the rich side, so it's possible you may actually need to decrease the additional cubic inches you gave the system a little bit. Ideally you want to get your learn values and trims as close to zero as possible, so there's some trial and error here.

Others may differ, but here's what I would do.

1. Sort out your timing situation and very 100% that the timing you are seeing through the light is accurate and if not, correct that
2. Once you've verified your timing is accurate, warm the car up and go do a full load pull from as low of an rpm to your max rpm and datalog it.

What I would be interested in with that datalog is what your indicated AFR is vs your commanded afr as well as your fuel learn and fuel trim.

The factory settings for learn max out at -35 and +50. The learn is the over-time modification to the VE table and the trim is the further change on top of that modified value. If you are seeing learn values near, or at maximum (in either direction), you need to modify the VE table by either correcting it manually in the ProCal software, or reducing (or increasing) the basic engine setup map. The closer you get the learn and trim values to 0, the more room the ecu will have to make adjustments based on different driving conditions and fuel qualities

[er455]

Thanks Jason I see you are familiar with the fitech and E85 that’s cool . I need to get a data log and would like to send it to you to look over for sure .

[JLMounce]

I can certainly look over it, but I am no guru. I would strongly suggest posting it also to the FiTech Owners Group on Facebook. There are several experts in speed density and alpha-n tuning strategies present there that can provide probably greater insight.

[er455]

Ok cool

[blueghoast]

I'm running a 8-71 blower and I was going to use my multi-step to
pull timing at 4500 rpm probly 8* do you think that is wise.
I know it's a lot at once but that all I got right now for timing control?
Thanks for any info. I've learned a lot just reading thru here.
It seamed when I ask a question I got a snotty response from some.
So I've been setting back and reading others questions. Very informative.

Thanks GT.

[Tom Vaught]

Look at it this way:
Naturally aspirated the pressure going into the engine is 14.7 (sea level conditions for this example) psi.
The Pontiac distributor has a vacuum can that adds say 10-12 degrees of additional timing under light load/cruising conditions. So if you have 32 degrees of Initial and Centrifugal timing under a light load cruise condition you could have 40 or 42 degrees of timing in the engine.
(THIS IS JUST AN EXAMPLE OF HOW IGNITION TIMING WORKS)

So you add more load to the engine quickly and two things happen. 1) the load on the engine is higher so the vacuum in the intake manifold drops (dropping the vacuum in the "timing advance vacuum can" on the distributor) and the 42 degrees of total timing goes very quickly back to 32 degrees of timing.
You did not hurt the engine by doing this. It happens thousands of times in a month of driving on the street with a Pontiac stock ignition system.

So now you want to remove 8 degrees of timing at 4500 rpm. 8 degrees of timing removed would make your engine less fuel efficient but happier under the higher load condition with less timing.

Unless you are cruising at 4500 rpm on the highway, not likely, you are in an acceleration mode (higher load) so the reduced timing function is a normal situation under higher engine loads.

The question is "When does it seem the "happiest" under that condition".
8 degrees removed, 4 degrees removed, 10 degrees removed? That takes some tuning time to find out as each engine is different.

Read the plugs, play with the timing, and find out what your engine is happy with for the fuel you are using vs the way the engine is built.

JMT (Just my Thoughts on the subject)

Tom V.

[Boostedbird]

er455, have you checked backpressure yet? I'm not sure what that cam has for overlap, but if you have a decent amount you'll need a really good flowing exhaust. I just put my full exhaust back on and lost 2psi. It's 5" to the transmission and 4" out the back with a Dynamax Ultra Flow 4" muffler. I put the boost back into it but the 5" open pipe definitely makes more power. If you have a lot of overlap, a smallish exhaust wheel, tons of exhaust from the E85, and a restrictive exhaust I can see where you'd have some problems. My $.02.

[er455]

Originally Posted by Boostedbird

er455, have you checked backpressure yet? I'm not sure what that cam has for overlap, but if you have a decent amount you'll need a really good flowing exhaust. I just put my full exhaust back on and lost 2psi. It's 5" to the transmission and 4" out the back with a Dynamax Ultra Flow 4" muffler. I put the boost back into it but the 5" open pipe definitely makes more power. If you have a lot of overlap, a smallish exhaust wheel, tons of exhaust from the E85, and a restrictive exhaust I can see where you'd have some problems. My $.02.

Funny you say that , I just had a new custom 3” stainless exhaust ran out the back from my old 2.5 pipes system with a transverse muffler and after that is when it felt a tad slower ... but I should have helped the back pressure by going to bigger pipe and a 3.5 “ downpipe ....I have a new harmonic balancer coming and I hope that the timing marks are not accurate with my old professional products one . Thanks , will let u know what I find out with the balancer .. do you think 2-4 degrees off of timing can wake up a turbo motor ??

[Boostedbird]

Originally Posted by er455

Funny you say that , I just had a new custom 3” stainless exhaust ran out the back from my old 2.5 pipes system with a transverse muffler and after that is when it felt a tad slower ... but I should have helped the back pressure by going to bigger pipe and a 3.5 “ downpipe ....I have a new harmonic balancer coming and I hope that the timing marks are not accurate with my old professional products one . Thanks , will let u know what I find out with the balancer .. do you think 2-4 degrees off of timing can wake up a turbo motor ??

Timing will make a huge difference, yes. In my opinion your downpipe is way small. I would go to atleast a 4", 5" if you have the room, and put something like a Loud valve cut out off the downpipe. That way you can keep your exhaust. The 3.5" downpipe doesn't have much more area than one of your 3" pipes. Here's a little chart showing area of pipes.

[Tom Vaught]

Pic #1, post #28, WHY DO YOU HAVE THAT MERGE PIPE INSTALLED IN THE OPPOSITE DIRECTION FROM WHAT IT WAS DESIGNED TO BE RUN AT. You come off of the single pipe, REDUCE the area of the pipe, then split the pipe into two pipes and expect that to flow some exhaust? IMO The actual flow area at that point looks like it is less than ONE of the dual pipes area farther down stream.

Tom V.

[er455]

Originally Posted by Boostedbird

Timing will make a huge difference, yes. In my opinion your downpipe is way small. I would go to atleast a 4", 5" if you have the room, and put something like a Loud valve cut out off the downpipe. That way you can keep your exhaust. The 3.5" downpipe doesn't have much more area than one of your 3" pipes. Here's a little chart showing area of pipes.

Wow did not think the 3.5 “ was that restrictive , I might be able to fit a 4” have to do some test fitting when I take my down pipe off next time .... what size were you able to fit ? We have the same car basically.

[er455]

Originally Posted by Tom Vaught

Pic #1, post #28, WHY DO YOU HAVE THAT MERGE PIPE INSTALLED IN THE OPPOSITE DIRECTION FROM WHAT IT WAS DESIGNED TO BE RUN AT. You come off of the single pipe, REDUCE the area of the pipe, then split the pipe into two pipes and expect that to flow some exhaust? IMO The actual flow area at that point looks like it is less than ONE of the dual pipes area farther down stream.

Tom V.

How else can you run dual exhaust without splitting it somewhere ? This is the exact setup all the Buick grand nationals run well into the 9,s I am going from 3.5 “ merge pipe to dual 3” pipes , I would like to have a 4” downpipe but not sure I can fit it ..

[Boostedbird]

Originally Posted by er455

How else can you run dual exhaust without splitting it somewhere ? This is the exact setup all the Buick grand nationals run well into the 9,s I am going from 3.5 “ merge pipe to dual 3” pipes , I would like to have a 4” downpipe but not sure I can fit it ..

Tom's right, that merge piece is absolutely killing any flow that you had. You need a larger downpipe, a merge something like the one in the picture or a custom one, and probably an electric cut out or a Loud Valve on the downpipe.
You asked about my exhaust. I have a 5" downpipe that runs from the turbo down to about the rear of the transmission where I smoothly transitioned down to 4". It stays 4" back to the bumper where my 4" muffler is. The muffler is a Dynamax Ultra Flow. It's straight through and pretty much just changes the sound a little. I'm either gonna put a 4" Loud Valve dump on the downpipe up front or run a second 4" pipe from the 5" to 4" transition.

[er455]

Originally Posted by Boostedbird

Tom's right, that merge piece is absolutely killing any flow that you had. You need a larger downpipe, a merge something like the one in the picture or a custom one, and probably an electric cut out or a Loud Valve on the downpipe.
You asked about my exhaust. I have a 5" downpipe that runs from the turbo down to about the rear of the transmission where I smoothly transitioned down to 4". It stays 4" back to the bumper where my 4" muffler is. The muffler is a Dynamax Ultra Flow. It's straight through and pretty much just changes the sound a little. I'm either gonna put a 4" Loud Valve dump on the downpipe up front or run a second 4" pipe from the 5" to 4" transition.

Ok maybe my pics are not showing what I have the merge pipe looks like the one you posted here is a pic of what’s on my car ...

[Tom Vaught]

I say BS to your last post and the pic you show. The picture that you posted is a GENERIC PICTURE from their website of a MERGE COLLECTOR and does not represent the actual piece that you showed in your other pics.
Obvious that the pipe bends are not even close to being the same. Post a pic or YOUR PIECE tonight tonight with a tape measure next to the merge piece. Then we can compare the transitions and bends..

The piece you posted resembles the design of the your picture.

Tom V.

[er455]

Originally Posted by Tom Vaught

I say BS to your last post and the pic you show. The picture that you posted is a GENERIC PICTURE from their website of a MERGE COLLECTOR and does not represent the actual piece that you showed in your other pics.
Obvious that the pipe bends are not even close to being the same. Post a pic or YOUR PIECE tonight tonight with a tape measure next to the merge piece. Then we can compare the transitions and bends..

The piece you posted resembles the design of the your picture.

Tom V.

Here is the best pic I can get without jacking the car up ... the merge pipe is 3.5” with a v band clamp going into 2 - 3” pipes exactly like I posted it’s made by vibrant ...

[JLMounce]

Those pics are better. It doesn't look as bad, but it really looks like this thing is first necking down to a 3" diameter before splitting into two. So instead of going from an area of 9 sq" into a theoretical area of 18 sp", you actually neck down first to a 3" pipe at around 7 sq" of volume, before the transition to 2 pipes.

It's something to take a look at for sure. It's connected with a v band to your down-pipe. Try disconnecting the back of the exhaust and take the car out to see how it feels. If it wakes up, you know you've found at least part of your issue.

[er455]

Originally Posted by Tom Vaught

I say BS to your last post and the pic you show. The picture that you posted is a GENERIC PICTURE from their website of a MERGE COLLECTOR and does not represent the actual piece that you showed in your other pics.
Obvious that the pipe bends are not even close to being the same. Post a pic or YOUR PIECE tonight tonight with a tape measure next to the merge piece. Then we can compare the transitions and bends..

The piece you posted resembles the design of the your picture.

Tom V.

Tom maybe your not seeing the pic clearly or the angles I took might look diferent but I know what’s on my car ... why would I BS ??

[Tom Vaught]

Your transition on the left (where it necks down)
needs to be a bunch longer and larger.

The merge works ok if the flow is in the other direction because of the cylunder firings. Think Tri-Y headers. You have constant flow from the Turbo trying to squeeze thru that necked down merge before it goes to the two pipes.

As was posted better to have done a longer/ larger single pipe and have the much more gradual merge to two mufflers happen farther toward the rear axle. The BS is the way the parts were installed, not you personally.

Tom V.

[er455]

Originally Posted by Tom Vaught

Your transition on the left (where it necks down)
needs to be a bunch longer and larger.

The merge works ok if the flow is in the other direction because of the cylunder firings. Think Tri-Y headers. You have constant flow from the Turbo trying to squeeze thru that necked down merge before it goes to the two pipes.

As was posted better to have done a longer/ larger single pipe and have the much more gradual merge to two mufflers happen farther toward the rear axle. The BS is the way the parts were installed, not you personally.

Tom V.

Ok yea I am going to try to squeeze a bigger 4” section on my downpipe like u mention before .. thanks