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-   -   Starting off the new year with an engine pull! (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/starting-off-new-year-engine-pull-880500/)

HardHitter 02-05-11 04:46 PM

Got some brand new OEM gaskets for $80 a piece. Couldn't pass that up

GoodfellaFD3S 02-05-11 11:05 PM

Which OEM gaskets are you referring to?

Narfle 02-06-11 01:46 AM


Originally Posted by HardHitter (Post 10443538)
Going to try and figure out the reason for the "lower numbers"

When I had the car looked over, there seems to be an exhaust leak coming from where my turbo manifold meets my motor. Could this play a large roll?

Tight tolerances on a new engine. That exhaust leak isn't helping. For a conservative tune at 13psi I think you're making good power with that turbo. What type of dyno were you on?

HardHitter 02-06-11 12:22 PM


Originally Posted by GoodfellaFD3S (Post 10455766)
Which OEM gaskets are you referring to?

Rich, I got 2 OEM turbo manifold gaskets.


Originally Posted by Barban (Post 10455904)
Tight tolerances on a new engine. That exhaust leak isn't helping. For a conservative tune at 13psi I think you're making good power with that turbo. What type of dyno were you on?

I was running on a conservative tune for 15psi. Steve said that he retarded the timing just a little, but he said it'd only be a 5-10rwhp difference at most. We will see, he comes back in March and I'm getting another tune, this time with my water injection going and possibly 17psi. If I start reaching the 400+rwhp mark at 15psi, then I'm going to keep it at that.

HardHitter 02-19-11 04:23 PM

So I finally got the chance to replace my turbo exhaust manifold gaskets.

Here are the gaskets that were on there...I have no idea if these were just pre-made or what the heck type of gaskets these are...

http://i42.photobucket.com/albums/e3...4/IMAG0229.jpg
http://i42.photobucket.com/albums/e3...4/IMAG0228.jpg

Here is what I replaced them with, OEM Mazda gaskets. Hopefully it solves any type of leaks...

http://i42.photobucket.com/albums/e3...4/IMAG0227.jpg
http://i42.photobucket.com/albums/e3...4/IMAG0226.jpg

Narfle 02-19-11 04:45 PM

You definitely had a substantial exhaust leak.

HardHitter 02-19-11 05:56 PM

Yea, I am hoping this fixes my "power loss" problem.

I went to get a tune with my setup and I was only pushing 345rwhp at 15-16psi. Most setups would be pushing close to 450rwhp. Don't know if it could make up 100rwhp but we will see if there is any benefit to switching out the gaskets.

Narfle 02-19-11 06:17 PM


Originally Posted by HardHitter (Post 10478208)
Yea, I am hoping this fixes my "power loss" problem.

I went to get a tune with my setup and I was only pushing 345rwhp at 15-16psi. Most setups would be pushing close to 450rwhp. Don't know if it could make up 100rwhp but we will see if there is any benefit to switching out the gaskets.

What type of dyno are you on? It makes a big difference. There's a lot of power to be gained in aggressive timing and fueling. But, living on the edge has it's disadvantages. Also, I think 450 is optimistic at 1bar.

HardHitter 02-19-11 07:14 PM

Car was dyno'd on a typical dynojet by Steve Kan. It was on a brand new engine still so maybe the seals just hadn't set in? I had around 900+ miles on the new motor and then when he came in, he tuned it and it was the first time the car going into boost and WOT. He tuned the car conservative because my water injection wasn't working, but he said it would only be around another 5-10rwhp so there had to be something else. Boost was holding 15-16psi, spark was fine, brand new spark plugs and ignition was fine, so maybe I'm lucky and it was a simple fix of these gaskets.

Steve is coming back in March and he is going to tune the car with my water injection. I've put a couple more hundred miles on the car since the last tune. Going to have a tune for around 16-17psi. I think that will be good enough for now.

RotaryEvolution 02-19-11 07:28 PM

check the manifold for warpage before you slap it back on.

HardHitter 02-19-11 07:36 PM


Originally Posted by Karack (Post 10478312)
check the manifold for warpage before you slap it back on.

*Palm to face*

It's already bolted back on and everything :(

GoodfellaFD3S 02-19-11 07:43 PM

Which orientation did you install the OEM manifold to block gaskets in? Hope there isn't a second face palm coming here.

Howard Coleman 02-19-11 08:00 PM

your manifold face is warped

KD-93R1 02-19-11 08:11 PM

Manifold flanges...
 

Originally Posted by Howard Coleman CPR (Post 10478357)
your manifold face is warped

Those one gaskets look a little odd? I like the OEM MAZDA ones which I see you have now. I'm wondering how those others even got there, but those may be normal on some I dont know. I've never seen em though.

Since Goodfellas, not to mention Howard are giving advice, I guess this is where I get off. Your in good hands.

Narfle 02-19-11 08:45 PM

I wonder if that wasn't the origin of the smoke you were observing.

HardHitter 02-20-11 03:37 AM


Originally Posted by GoodfellaFD3S (Post 10478337)
Which orientation did you install the OEM manifold to block gaskets in? Hope there isn't a second face palm coming here.

Rich, I read the Mazda manual and it was showing how it shows in picture #2. Basically, the "smooth" side is against the engine. If you're looking at the engine with the turbo manifold off, you'll be looking at picture 2.

Howard, care to let me know how/what you see to know that my manifold is warped?

Howard Coleman 02-20-11 11:08 AM

picture 2 shows a great deal of carbon coming from both exhaust ports. there should be no carbon on the gasket. either your manifold is warped or the top two nuts were not torqued to spec.

there is a significant amount of heat into the stainless steel flange during the welding process and stainless steel warps more than most materials. generally, the flange needs to be reground flat after the build process.

i found my manifold was leaking on it's maiden dyno run and had it ground. no leaks now.

as above, it could be your manifold is flat and the nuts weren't properly tightend. if this was the case the manifold can (then) warp from being loose as it is then exposed to high temp exhaust gas where leaking.

so do take a good at it. it should be dead flat.. within a thousandth of an inch.

howard

HardHitter 02-20-11 12:01 PM

Is there a way to take a look at this by not having to take the manifold all the way off? For when I changed my gaskets I just removed my wastegate, disconnected my downpipe from the exhaust and removed some the oil feed/return line to be able to push it off the bolts to slide the new gaskets on. Would any gap be noticeable to the naked eye?

Howard Coleman 02-21-11 09:40 AM

leaking exhaust manifolds deposit carbon on the engine. check the engine at the falnge area for carbon.

BTW, to be clear, i shouldn't have said your manifold is necessarily warped as it could be the nuts were not sufficiently torqued.

it is, however, one or the other or both

hc

Prometheus 02-21-11 10:23 AM

Have your manifold face lapped, if it's less tgan 1/2" thick, get a new manifold.

The thicker the flanges, the better.

Stainless moves A LOT.

HardHitter 03-22-11 10:39 PM

Thought I'd go ahead and give an update on the car.

This past weekend, Steve Kan flew in again and tuned my car. I hadn't changed much with the car since the last tune. Maybe put on 300 miles on the motor, installed brand new OEM manifold gaskets and got my water injection working.

The final numbers ended up being 406rwhp/325rwtq @ 18psi. An increase of 62rwhp/56rwtq and 2psi.

I am pretty happy with the numbers, but in comparing my setup with Rich (we basically have the same exact setups) he is almost 90rwhp more than my setup.

I'm trying to figure out where the bottlenecks of my setup are in stealing power away.

Future things I need to improve:
1. Rewire my fuel pump. Steve said that I am at about 87% duty cycle
2. Order thicker coupers/better clamps/flare IC piping. During the pulls the coupler was blowing off because the IC piping had no flare to clamp to
3. Think about possibly running 50/50 water and meth setup for next tune.

Haven't been able to feel what the extra 60rwhp feels like as it was raining during the day of my tune and I was already breaking loose in 3rd gear just casually driving over to the tune.

I'm excited for some sun!

This is showing two results.

Blue is when Steve came in January to tune the car @ 16PSI
Red is the most recent tune @ 18psi with water injection

http://i42.photobucket.com/albums/e3...4/IMAG0294.jpg

Narfle 03-23-11 12:18 AM

I think you've got a boost leak. Especially if you're blowing couplers off.


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