1001 replies to this topic

[Steve Scheifler]

Steve, do you think those minor changes you named would make the NA 1.6 competitive with the NB & NB vvt?

If a 1.6 is not competitive in the first few laps on a cool day now, then no. I think the proposed changes will make it easier to have a "good" header, but in theory a "top prep" already has that, and allow it to finish better rather by losing less power to hot I take air. The flywheel will help slightly in 2nd gear and less up from there but is unlikely to be evident in lap times or data unless you are super consistent and have 2nd gear corners.

So if a top prep 1.6 can't keep up with the NBs early in the race now, they still won't. But if they can keep up early now other than getting checked up in 2nd, then this might help them there and later in the race.

My best guess anyway.

[Steve Scheifler]

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[38bfast]

Steve a good percentage of the 1.6 cars did not even know about the weight change at the beginning of the year.

[Steve Scheifler]

Probably true Ralph, but that should not in ANY way influence what decisions are made. That very fact is proof that they fit into the "just for fun" crowd, which is fine but parity adjustments have never been based on them.

[jdmrrs]

Bench Racer,

The ABCC dyno comparison was 1.6 before and after the header. The track tests were the 1.6 and a '99. Summarized results in a letter to SMAC. Be glad to share 1.6 results if helpful. We did not want to start an "arms race" but also wanted to avoid two sets of rules (aka "Majors/National" & "Regional supplements"). So far, our members, as a whole, seem happy - which was our goal.

[Bench Racer]

Jim, thank you for the summarized results letter to the SMAC.

[Tom Hampton]

Bench Racer,
The ABCC dyno comparison was 1.6 before and after the header. The track tests were the 1.6 and a '99. Summarized results in a letter to SMAC. Be glad to share 1.6 results if helpful. We did not want to start an "arms race" but also wanted to avoid two sets of rules (aka "Majors/National" & "Regional supplements"). So far, our members, as a whole, seem happy - which was our goal.

Jim=

If you don't mind, I would like to see the summarized results. I was just planning g on doing some similar testing to support a letter. But, if you've already done that on several cars that carries more weight. So, I might as well cast my vote in support of your data. Others here might be willing to do the same after review.

[jdmrrs]

OK, as requested, here is the basic data from the Midwest Eurosport dyno where owner George Weathered tuned the car. We optimized output on a strong, fairly fresh Stewart motor with and without a Racing Beat header. We chose the specific header based on word-of-mouth recommendations and Racing Beat's wealth of published dyno results.

 

RPM/T/HP (OEM) >> T/HP (Header)'

4400 110/93>>115/97, 4600 111/97>>116/102, 4800 113/103>>116/106, 5000 113/107>>116/110, 5200 113/112>>117/115, 5400 112/115>>115/118, 5600 114/122>>116/124, 5800 112/123>>113/125, 6000 109/125>>112/127, 6200 107/127>>110/130, 6400 105/127>>107/131, 6600 100/126>>104/131 ...

 

I pulled these numbers from the hard copy, so my reading of the graphs is +/- 1 unit.

[Danny Steyn]

Jim thanks for sharing your data. This is the sort of thing that helps us make informed decisions.

 

SO Jim, If I read your numbers correctly, at the following RPM's the Racing Beat header provided a net gain of

 

5,000 RPM - 3HP / 3TQ

5,600 RPM - 2HP / 2TQ

6,000 RPM - 2HP / 3TQ

6,600 RPM - 5HP / 4TQ

 

These are very impressive numbers if they are achieved with only a header.

What is the cost of the header?

Do you still have access to the dyno files for the car with and without the header? These would be very valuable

[jdmrrs]

The header was about $450, and a nicely built piece. The results were, better than I expected (being a skeptic), similar to Racing Beat's claimed magnitude of improvement but less than the "SCCA special committee" data posted earlier on this site for another brand header.

I will call George at Midwest Eurosport and see if I can electronically grab the file.

[Mark McCallister]

IMHO, if those numbers are close to right, it will address the torque deficit and eliminate a cheat, should be close to a no brainer.  Nobody, including budget racers like me, should complain about a one-time bolt-on that costs less than a set of tires.  SCCA ought to be able to negotiate a discount with whoever's piece gets specified, as there will be quantity savings in production.  May have to add a plate to the 1.6 to knock the top end back down, but I'm fine with that.  Much better than the can of worms and questionable benefits with the flywheel mods.  It would be nice to confirm that there are no blatant induced fitment problems with the popular exhausts with the change.  Should we specify that header wrapping is OK from the start?

[LarryKing]

Should we specify that header wrapping is OK from the start?

[Ron Alan]

If those numbers are at all accurate...you can kiss that idea goodbye

 

https://www.google.c...CFcs2iAodwVoNsw

[Bench Racer]

Approve, track test, if it's a Mastiff, open up the 97 plus cars restrictor plates, win win.

[Steve Scheifler]

Wrap tends to cause header tubes to overheat and get brittle, shortening their life. The RB piece is stainless so it's less of a problem (I think) but it also inherently needs much less shielding than mild ferrous steel. Regardless, I would prefer a good heat shield over wrap.

Regardless, single-source spec parts are not popular with some on the SMAC, for good reason. At the same time, let's not encourage a lot of new R&D even if most of it would be hype. I wonder how many would actually sell in the first year? Guarantees on consistency, price and supply might be possible with a long established and stable company. I would think that closer to $350 each would still be a very attractive opportunity.

[LarryKing]

 

If those numbers are at all accurate...you can kiss that idea goodbye

 

I agree, a good header has the potential to make the 1.6 competitive with the NB and, well, you know, WE CAN'T HAVE THAT.

[MPR22]

As an owner of most of the models I will support a header for the 1.6.  

[Ron Alan]

I agree, a good header has the potential to make the 1.6 competitive with the NB and, well, you know, WE CAN'T HAVE THAT.

You take a very good 1.6 car and give it those gains...you will not have any 99 cars at the front of the field...because all the pointy end guys will be driving a 1.6!

 

125/107 and 2275 will be unbeatable on the West Coast given equal drivers! Take that for what its worth because i'm only comparing CA drivers...

 

And 1.6 drivers...gaining back 50 or 75 lbs is not worth a bump like this IMO

[38bfast]

Just for reference.

 

From past testing on the 1.8, 99 and VVT cars the restrictor plates effected the entire HP/TQ curve. It did not affect just the top end or just the bottom end. I do not have any data on how exactly a plate would effect a 1.6. 

 

Adding weight to a car tends to counter act torque. Hence why the VVT cars are currently enjoying a 25 Lb gain over the 99s. 

 

just food for thought.

[LarryKing]

 

125/107 and 2275 will be unbeatable on the West Coast given equal drivers!

 

I know all dynos read differently - 123-124 hp from a 1.6 is the current 'high' normal for cars in the Great Lakes. We ain't taking THAT big of a jump.

 

 

You take a very good 1.6 car and give it those gains...you will not have any 99 cars at the front of the field...because all the pointy end guys will be driving a 1.6!

 

You got any data to back that up? Or is this like "Mazda Raceway/Laguna Seca is a 1.6 track" ?