825 replies to this topic

[speedengineer]

The fuel deal IMO is weak pump.. When I have a good pump in the car it hardly bleeds down at all. A tired one bleeds down quickly as you describe. Bennett cut one open a fuel years ago and did a thread on it somewhere. He didnt believe the pressure hold correlated with pump going.  IMO , it always seems to follow.

 

If you are starting with a used pump, I think that is a bad decision. They are a common fail issue and hate to save $100 to only burn the engine down.

 

Jim

Thanks for the info Jim.  But how am I going to build for under $15k if I have to replace stuff like fuel pumps   

 

By Saul Speedwell aka Mark Bennett.

 

https://www.youtube.com/...

Ah yes, good info here, thanks for the link, and Mark for doing that video.

 

Why are you running the AC fan?

 

Are you comparing a new MM to an Old MM that may account for some change over a 15 years.

Ac fan for more cooling of course!  The way I figure:

- Miatas get hot on the track, but not when running by themselves, only in the draft

- In the draft, airflow through the radiator is limited.  Thus cooling is 'air side limited' not water side limited with respect to heat capacitance rate.

- If airflow is insufficient to control temps, pull more air through.  Hence better to leave both fans in place. 

 

MM?

 

 

 

So fuel pumps.  Mazda is $$$.  Lots of aftermarket ones out there.  Some are clearly not oem equivalent as they require splicing wires in, etc.  Others, even some of the cheapest ones, appear to be a plug n play option.  Any recommendations?  I'm not sure if the argument that 'go oem cause it's the best quality' is necessarily true, I'd be surprised if the pump mazda sells now is truly identical to the pump that came in the car 17 years ago. 

[Jamz14]

I just went through this Jason. The aftermarket pumps are POS ( pieces of shit. For the initialism library Johnny). At least as far as fitment goes. It wasn't just wire splicing. The lower support flange was way different than the OEM. But you could probably fab a new one easy cheesy.

[Brandon]

You're only allowed a single cooling fan.  The second fan only came with the AC package so unless you're running the full AC system, you can only have the single fan per the GCR.

 

Weenie protest but definitely not legal if you have removed all the other AC bits.

[Todd Green]

You're only allowed a single cooling fan.

 

What rule states that?  GCR 9.1.7.n.2 says, "At least one functional stock OEM cooling fan must be maintained and mounted in the stock location." (NASA rules are identical.)

[speedengineer]

I just went through this Jason. The aftermarket pumps are POS ( pieces of shit. For the initialism library Johnny). At least as far as fitment goes. It wasn't just wire splicing. The lower support flange was way different than the OEM. But you could probably fab a new one easy cheesy.

  Darn!  Assuming I get one of the aftermarket ones that has factory style electrical hookups, and deal with the lower support flange, how did the rest of the quality look?  Working ok I assume, or did you decide to get the mazda pump?

 

You're only allowed a single cooling fan.  The second fan only came with the AC package so unless you're running the full AC system, you can only have the single fan per the GCR.

 

Weenie protest but definitely not legal if you have removed all the other AC bits.

Hmm.  I'm not sure I agree with that.  I can see where you're coming from that the 2nd fan is a part of the AC system.  But at the same time, the rules explicitly say that "at least one" fan must be used.  Secondly, even if other AC bits were removed, if you define the 2nd fan as 'dual purpose' for condenser cooling as well as radiator cooling, then I'm not sure you're allowed to remove it anyway. 

 

 

Any radiator (and mounting brackets) may be used,
provided it is mounted in the original location, maintains
the same plane as the original core, and requires no body

or structure modifications to install. Any openings created
by fitting an alternate radiator must be blocked to prevent
air from entering the engine compartment. At least one
functional stock OEM cooling fan must be maintained and
mounted in the stock location. The fan shroud may be
modified for installation.

 

The factory air conditioning systems may be removed.
Items that serve a dual purpose, such as the alternator/air
conditioning compressor bracket, may not be substituted.

[Jamz14]

The pressure put out by the aftermarket pump looked good. However, because I had a problem with the tree the pump mounts to, I bought an entire new pump and mounting tree from Mazda. In addition, Jim and Dave were dead on with regard to where the problem for me was. So I pay attention when they tell me that the pump itself is also an issue. Not worth risking the engine for the difference in price.

 

Be prepared to have to buy the entire assembly. My build started right up in the shop. Worked just fine taking it out on a quick street run. But once it went to the track and was able to really lean into the lefthanders.........multiple seconds of cutting out.

[Brandon]

Everyone always likes to read rules in isolation to the rest of the section(s).

 

If your car came with AC, you have additional components (compressor, compressor/alternator bracket, drier, condenser, second fan) that must be completely removed should you choose to remove the particular system.  Our rules have carve-outs for various other "systems" (one in particular is the power steering - you can run the power rack w/o the pump, bracket, pulley, reservoir, hoses & belt) that allow you to pick and choose but the AC systems is not one of them.

 

The second fan was, and has always been, part of the AC system and if you have removed the other bits, the second fan must also be removed.  Trying to designate the second fan as being a "dual-use" component would probably be considered a tortuous interpretation.

 

As I said earlier, it's a weenie protest, but one that would probably be upheld.  If you don't want to be protested for running dual fans, then I suggest writing letters for either the allowance or clarification on whether the second fan actually is considered "part of the AC system" and needs to be removed with the rest of the AC components.

[Michael Novak]

you will be fine with one or two fans...  The at least one means one or more clearly

[FTodaro]

I did not want to be the one to start it but i have never seen anyone use both fans, in order to get both to work you would have to splice the second fan into the first. I am just thinking if this would fly we all would be doing it, but what do i know.

 

Better to hash it out now than in Tech, regarding a protest, stuff like this is obvious so if the have a problem you will hear about it.

 

Novak does not own a rule book.

[Mike Collins]

Brandon, in this case you really don't know what you're talking about...

 

 

Any radiator (and mounting brackets) may be used, provided it is mounted in the original location, maintains the same plane as the original core, and requires no body or structure modifications to install. Any openings created by fitting an alternate radiator must be blocked to prevent air from entering the engine compartment. At least one functional stock OEM cooling fan must be maintained and mounted in the stock location. The fan shroud may be modified for installation. 

 

The factory air conditioning systems may be removed. Items that serve a dual purpose, such as the alternator/air conditioning compressor bracket, may not be substituted. 

 

Its not a weenie protest and you wouldn't win... Ive written more protest than everyone else on this board combined (twice over)...  You can leave the A/C fan in the car and you can leave the A/C fan switch in the the center console and if you turn the switch on and your A/C fan comes on that is legal too.....

[Mike Collins]

Brandon, in this case you really don't know what you're talking about...

 

 

Any radiator (and mounting brackets) may be used, provided it is mounted in the original location, maintains the same plane as the original core, and requires no body or structure modifications to install. Any openings created by fitting an alternate radiator must be blocked to prevent air from entering the engine compartment. At least one functional stock OEM cooling fan must be maintained and mounted in the stock location. The fan shroud may be modified for installation. 

 

The factory air conditioning systems may be removed. Items that serve a dual purpose, such as the alternator/air conditioning compressor bracket, may not be substituted. 

 

Its not a weenie protest and you wouldn't win... Ive written more protest than everyone else on this board combined (twice over)...  You can leave the A/C fan in the car and you can leave the A/C fan switch in the the center console and if you turn the switch on and your A/C fan comes on that is legal too.....

Ask me or Dave W. or Drago how we know.....

[davew]

The "not holding pressure" is not a problem in itself. Cutting out on corners is a problem. If you feel the need to replace a pump, USE ONLY THE MAZDA ASSEMBLY. Sometimes it pays to listen to the people who have been through this before. USE ONLY THE MAZDA ASSEMBLY. 

[Jim Drago]

Brandon, in this case you really don't know what you're talking about...

 

 

Any radiator (and mounting brackets) may be used, provided it is mounted in the original location, maintains the same plane as the original core, and requires no body or structure modifications to install. Any openings created by fitting an alternate radiator must be blocked to prevent air from entering the engine compartment. At least one functional stock OEM cooling fan must be maintained and mounted in the stock location. The fan shroud may be modified for installation. 

 

The factory air conditioning systems may be removed. Items that serve a dual purpose, such as the alternator/air conditioning compressor bracket, may not be substituted. 

 

Its not a weenie protest and you wouldn't win... Ive written more protest than everyone else on this board combined (twice over)...  You can leave the A/C fan in the car and you can leave the A/C fan switch in the the center console and if you turn the switch on and your A/C fan comes on that is legal too.....

Completely agree! So much so that I ran two fans at Daytona Runoffs and a bigger radiator to stay in draft 1/2 lap longer than others could.. didn't matter, but read the rule before installing and absolutely agree with Mike 100%. Run two fans if you wish. 

[38bfast]

Sounds like everyone is blowing a lot of hot air.

Couldn't resist the pun

[speedengineer]

So, I did some troubleshooting on the 'fuel pressure not holding' issue tonight.  I removed the return line to the tank and blocked it off at the regulator.  When I cycled the fuel pump, pressure held real solidly.  Like indefinitely solidly.  So, this means my check valve in the fuel pump is in perfect working order, and unfortunately the issue is with the Fuelab regulator.  It leaks fuel back to the tank. 

 

In other news, wideband O2 is installed.  Temporary oil pressure gauge is installed until I get around to installing the AIM system later this summer.  Painted the shifter and installed.  Temporary aluminum block-off plate made for the radio slots - eventually I'll buy a two-way radio system and probably install it in one of the factory radio slots assuming it will fit there. 

 

 

Exhaust is all done.  Thank to Mike Novak and Roush for the donor exhaust system that I was able to start from!  I ended up just mig welding it.  Not as pretty as nice stainless tig welds, but hey, it's faster and likely just as strong. This baby sounds just like a SD exhaust haha.  I'm not sure if that's good or bad.....

 

 

[Todd Green]

 

that must be completely removed should you choose to remove the particular system. 

 

Again, where is the rule that says the entire system must be removed as a whole?  There is a large difference between may and must.  If some hypothetical rule says you may remove your interior and I choose to leave the dash in for aesthetics (or whatever) purposes but remove the rest you think that is protestable?  I'd disagree.  Even if that were the case, I'd still argue that the fan specific rule takes precedence.

 

ObOnTopic: Jason, you know you are getting close if you are down to painting the shifter!

[Jim Drago]

red shifter -.1, tan dash -.2



this one is +.2 a lap

Jim

[Erik Hardy]

Drago's shifter looks like the majority of people's faces at the beginning of this thread  

 

Man drama yo. haha

[ChrisA]

Are you going to count that AiM system toward the build budget or are you sneaking it in afterwards? They are pricy little buggers!

[speedengineer]

Are you going to count that AiM system toward the build budget or are you sneaking it in afterwards? They are pricy little buggers!

Yeah, the aim won't count in the budget, I'll sneak it in later.  Really when you think about it, the AIM isn't a needed item to make the car fast.  It'd help, sure, but mostly about driver improvement. 

 

I will include a 'base budget' for the car as raced, and also a 'total budget' that includes the data, and 16 sets of spares like all the picky bastards insist I need to include in the build cost, haha.