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Garage Quinn Motors - GQM
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Discussion Starter #1
I am posting this in the ITB section because I know my build thread is not seen as much throughout the board. I hope this will be of some use for people trying to make N/A power without getting into expensive and risky bottom end work.

The head on my engine is not ported at all, just shaved .060". Supposed to be around 11.5:1 compression now, but I am not sure if it was actually raised that much. The key here is making this setup easily reproducible. If the block fails, I can go buy another stock block and be up and running quick. If I needed a new head, I can buy one and the only machine work needed would be a 135.00 shave. No rotating assembly work, no clearancing (other than cold lash), no balancing, no porting, etc.

Engine:

2002 Block 10:1 compression
Cams are 264 / 264 10mm Lift Maruha's
Supertech Single Valve Springs
Supertech Titanium Retainers
Mazdaspeed SUBS
Toda Adjustable Cam Gears
New OEM Valve Seals
OEM Head Gasket
TWM 45mm Individual Throttle Bodies
36 lb Fuel Injectors
ITG Sausage filter and backing plate
Hondata Intake Manifold Gasket
Adaptronics Standalone ECU
Maruha VP Race Header
Racing Beat Resonated Race Pipe 2.375"
Jet's Integral Kobe Muffler 2.375"
Garage Star Alternator and Waterpump Pulleys
6.2 lb Spec Billet Pressure Plate
7.1 lb Fidanza Flywheel
1.3 lb Clutchnet Unsprung Street Disk
Golden Eagle Vacuum Manifold
Chikara Motorsports Oil Catch Can
Koyo 52mm Radiator
Koyo 1.3 Bar Radiator Cap
Mishimoto Slim Fan
Samco Radiator Hoses
Flyin Miata Oil Cooler Kit
Beatrush Radiator Cooling Panel

This stock 02 block at 10:1 compression, tested at 200-205 psi in each cylinder with the stock cams in previously. With the new cams creating more overlap and the head shave at .060" supposedly 11.5:1 compression, it tests at 205-210 psi in each cylinder. So with stock cams in the head creating less overlap it would most likely test much higher compression on the gauge. Honda's F20c at 11:1 compression on the non-VTEC lobes compression tests around 230-240 psi depending on the gauge.

With a .060" shave and 10:1 factory pistons, there is still a good 1-1.5mm of clearance in the reliefs. My friend/tuner was telling me to shave .080", but I was scared because the highest I was told I can go was .030", and I asked a lot of the big name Miata guys this too. I should have done .080". If the head ever comes off, I am going to shave it again to .080".

The results of all of this? Here are before and after comparisons of both the corrected dyno numbers and the uncorrected (what car was actually making at that very point in time). We fiddled with the cam gears on the street and on the dyno as well. These engines are not very sensitive to timing changes. Changing the cam and ignition timing yielded very little results. We advanced and retarded both the intake and exhaust cam quite a bit, but nothing significant changed. When we originally baselined the car it made 168 whp and 124 ft/lb's. We were however able to pick up a good chunk of mid-range power and settled with both the intake cam advanced about 6-7 degrees and the exhaust cam advanced about 3-4 degrees. We spent some time trying to get that funky dip out at 2600 rpm, but were only able to flatten it a little. We think it is just the nature of the cams and maybe the combination of them, the ITB's, and the header as well.

So there you have it. The idea behind this build was to avoid getting into costly bottom end work or head work and making the setup easily reproducible. Literally the only machine work required if the motor were to fail worst case would be shaving another head for 135.00.












 

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Awesome stuff man! What's the rev limit set at? I'd assume those cams like to rev a bit higher than oem red line. Your MS sub lifters should be good for it IMO.
Edit* looking at the dyno graph it seems the power plateau's at around 7800 rpm.. Not bad lol

Makes me wonder how much my engine would safely make using the ex-in cam and stock exhaust cam with a ported head and 84.5mm pistons.. I'll be glad if I can achieve 165 whp..

Enjoy the car, I bet it's sweet as **** to drive.
 

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I think you'll serve as an inspiration to everyone that wants to start on an N/A build on a budget, with good gains for the money. :)

Hmm..this makes me wonder if those dyno numbers Fuji Racing were actually true, seeing how their claimed numbers were pretty close to yours. :O
 

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Supporting Member
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2,284 Posts
Well..well..so this is what you have been up to over the winter..

i was in your area the other day and almost picked up the phone...good info here...

gimme a call if you get a chance...

Joe
 

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1,397 Posts
This is one awesome machine man & good information here. A great set up without the major costs of doing some building up of the bottom end as well.
 

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Got a few questions I guess somepeople might be thinking about.
1. What kind of gas are you using?
2. How are your rods? I've heard substained 7500+rpm is bad for them. I would probs run some cheap $300 rods, just swap in your old engines bearing, right? Should keep the same clearances, as the only thing difference would be the rods contacting the outer bearing surface, but then they are made to take stock bearings. Well, mean while your "replacement 01+" engine is in your backyard might as well work on it. And..balancing! I'm sure while your at the machine shop, this shouldnt break the bank. The question is, do you take the crank and flywheel to get balanced as well? Maybe pull the pistons out as well, a piston ring compressor shouldn't cost that much and it shouldn't be that difficult to take them out and put in for the newb.
3. For those that don't need $$$ lifters/specialty cams if you stay below 7800, or so I've read. Just adding to the thread.
4. Besides the awesome header, whatelse are you running as exhaust. Would using a 2.25 FM midpipe help?
4b.I've read that the stock 99 muffler flows well up to 6psi of boost, so I would think it would do fine for a moderate NA build or whatever 6psi equals to power-wise. I'm sure you used a different one due to weight and not flow. Correct?
5. What gains do you expect to see going from .060 to .080th of a shave?
5b. I've been told after a certain shave the top rubber of the waterpump doesn't fit and timing the engine/belt is more difficult as thing don't line up as well.
 

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I would like to hear the OP, but would like to comment on some of the items.

I built a pretty healthy motor, and because I was on a budget, I stuck with the stock rods. I turned my motor to 8000 on the occasion, but usually around 7500. I did not do any hard sustained runs like on a road coarse. Many trips down the drag strip, and some playing around on the street.

It is not like the stock exhaust will prevent you from making power with other mods up to a point. Doing so is not getting the most out of the motor or other mods. Uncorking a motor that inhales better will get considerable gains.
 

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Brunettes > Blondes
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so much awesome in this thread....so with the 99-00 head you wouldn't need a VVT tuner?
 

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so much awesome in this thread....so with the 99-00 head you wouldn't need a VVT tuner?
Just curious... if the 99-00 head, has no VVT... What in your mind would you think a VVTuner would need to control, if there is no VVT...?

Just trying to find the logic behind this question.
 

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brontosaurus
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7,236 Posts
No signs of detonation with 11:5 and pump?

Very impressive. Good job making everything work so well together.

Just 10hp shy of 949racings 182whp build. Which makes this even more impressive when you compare the two engines. Now I'm curious what that engine would have done with itbs and an extra point of compression...

This the perfect example of why building a 1.6 doesn't make a lot of sense.
 

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Brunettes > Blondes
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Just curious... if the 99-00 head, has no VVT... What in your mind would you think a VVTuner would need to control, if there is no VVT...?

Just trying to find the logic behind this question.
There was no logic behind the question. I don't know **** about VVT stuff. I apologize for being a noob. But thanks for answering my question!
 

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Garage Quinn Motors - GQM
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2,847 Posts
Discussion Starter #17
Got a few questions I guess somepeople might be thinking about.
1. What kind of gas are you using?
2. How are your rods? I've heard substained 7500+rpm is bad for them. I would probs run some cheap $300 rods, just swap in your old engines bearing, right? Should keep the same clearances, as the only thing difference would be the rods contacting the outer bearing surface, but then they are made to take stock bearings. Well, mean while your "replacement 01+" engine is in your backyard might as well work on it. And..balancing! I'm sure while your at the machine shop, this shouldnt break the bank. The question is, do you take the crank and flywheel to get balanced as well? Maybe pull the pistons out as well, a piston ring compressor shouldn't cost that much and it shouldn't be that difficult to take them out and put in for the newb.
3. For those that don't need $$$ lifters/specialty cams if you stay below 7800, or so I've read. Just adding to the thread.
4. Besides the awesome header, whatelse are you running as exhaust. Would using a 2.25 FM midpipe help?
4b.I've read that the stock 99 muffler flows well up to 6psi of boost, so I would think it would do fine for a moderate NA build or whatever 6psi equals to power-wise. I'm sure you used a different one due to weight and not flow. Correct?
5. What gains do you expect to see going from .060 to .080th of a shave?
5b. I've been told after a certain shave the top rubber of the waterpump doesn't fit and timing the engine/belt is more difficult as thing don't line up as well.
That would defeat the purpose of what I am doing here. I don't think you understand the repercussions of taking apart the rotating assembly. Factory stuff is assembled in the right conditions and clearanced properly. If you are going to go into the bottom end, you need to do it all and do it right. It's not going to be cheap and it certainly doesn't mean extra reliability. With timing tuned correctly, 7800 rpm is fine.

Exhaust is full 2.375" as noted above.

If I thew a stock exhaust on this setup I would certainly lose power. Why bottle neck all the high dollar parts when a matched flowing muffler costs less then 300.00?

You are throwing out a lot of random **** here, built motors, stock exhausts? You need to have a goal and build according to that goal. My goal was to pull as much horsepower out of my motor, while making the setup easily reproducible. Machine work, headwork, is not as easily reproduced and everytime you have a failure it costs that much more and takes that much longer to get your setup back up in running. I can easily have this car back up in running in a matter of hours by swapping in another stock 01-05 block. You can't do that with a built block. Replacement head? 1 day turn around for another shave. Only thing that will take time is waiting for lash caps to come in if I have to order more. Turn around for a ported head? Definitely longer. Will it match how the head was ported previously? Probably not. Will another built block and ported head cost a lot of money? You bet. Will the tune be the same? Probably not.

When I checked clearance after the shave, I did it with no head gasket. OEM gasket is .020, so it was actually simulating a .080 shave and it was fine.


I would like to hear the OP, but would like to comment on some of the items.

I built a pretty healthy motor, and because I was on a budget, I stuck with the stock rods. I turned my motor to 8000 on the occasion, but usually around 7500. I did not do any hard sustained runs like on a road coarse. Many trips down the drag strip, and some playing around on the street.

It is not like the stock exhaust will prevent you from making power with other mods up to a point. Doing so is not getting the most out of the motor or other mods. Uncorking a motor that inhales better will get considerable gains.
The tune is everything. Like I said before, advancing timing up top was not making anymore power, so we dialed it back, keeping the engine as smooth as possible without sacrificing power. When timing is advanced too much, this will put more strain on the rods and bearings. I am not worried about revving this engine to 7800 rpm.

No signs of detonation with 11:5 and pump?

Very impressive. Good job making everything work so well together.

Just 10hp shy of 949racings 182whp build. Which makes this even more impressive when you compare the two engines. Now I'm curious what that engine would have done with itbs and an extra point of compression...

This the perfect example of why building a 1.6 doesn't make a lot of sense.
No detonation issues whatsoever. The car is tuned on 93 octane, which is available everywhere in CT. What was the specs on the 949 car? Was that the 2.0L?
 

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Will likely be stealing this set-up. I'm not even shooting for those goals with a motor, I'd be content with 160whp, nice to see that's realistically possible. I've always not wanted to build an engine for my track car because if it blew I'd be out a lot of money, but now that I've seen a proven OEM based set-up, I might have to give this a shot. Like you say all the stuff that could potentially break is OEM and easily replaceable. Chances of tossing a rod so bad it takes out the ITBs or something isn't likely.
 

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brontosaurus
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7,236 Posts
No detonation issues whatsoever. The car is tuned on 93 octane, which is available everywhere in CT. What was the specs on the 949 car? Was that the 2.0L?

http://forum.miata.net/vb/showpost.php?p=5595635&postcount=1

Yeah, the "OGK" motor. I only mentioned it because its so well documented its kind of regarded as a bench mark across a lot of forums for what a built pump gas bp4w can do.

Your build is even more impressive when compared to FMs 11:1 stroker. Basically a $10, 000+ build.

http://forum.miata.net/vb/showpost.php?p=5493814&postcount=1

I'm only posting this because you seriously have done well with your build. Major props. I see this being replicated by quite a few people in the very near future.
 
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