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-   Time Slips and Dyno (https://www.rx7club.com/time-slips-dyno-128/)
-   -   386 RWHP @ 13PSI, Turbo-NA w/GT4088R, Aux Bridge, etc. (https://www.rx7club.com/time-slips-dyno-128/386-rwhp-%40-13psi-turbo-na-w-gt4088r-aux-bridge-etc-684320/)

Juiceh 10-01-07 12:28 PM


Originally Posted by Aaron Cake (Post 7298101)
I want to also have a "very" low boost setting for use in the rain or when traction could be an issue. Hence the lower PSI spring.

Screw that! Run high boost all the time!
https://www.rx7club.com/fdnewbie-imports-172/gb-racelogic-674843/

jacobcartmill 10-01-07 06:20 PM


Originally Posted by Aaron Cake (Post 7287899)
With each successive run we pulled a bit of fuel and gained between 10 and 20 HP every time. After approximately 6-8 runs (I lost count) the final number was 387 RWHP, 279 FT-LBS @ 13 PSI. A conservative estimate puts that right around 420 HP at the flywheel. Not half bad for an hour on the dyno on low boost. A/F ratios are in the mid 12s until about 5 PSI, falling to the mid 11s to 10 PSI, then low 11s to 13 PSI. Timing is still VERY conservative at 10 degrees. I could put a few degrees of timing into it right now and pick up a few more HP but I'd rather wait and borrow an EGT gauge (or buy a cheap one) before I start bumping timing too much.


10*@13psi is very low timing. of course i'm expecting you to take this with a grain of salt, as i'm just another guy posted in your thread on rx7club, but 10* is very low timing and i'm surprised the car is running as well as it is. that probably also explains the low tq numbers.
at 13psi i'd start from about 15* and add a degree or two with the EGT gauge.

what split are you running?

Aaron Cake 10-02-07 08:51 AM


Originally Posted by Terrh (Post 7385597)
nice results.
When I was making around that power level I was starting to have traction problems in 3rd, with an LSD...
If you plan on hitting up st. thomas this year and want to borrow my slicks just let me know, I see 11's in your future :)

I may be going to St. Thomas again on Friday as the weather looks good. It will probably be the last night with decent weather before the track closes. But of course, my car is 4 lug. :D


Originally Posted by t04tii (Post 7385842)
Why are HP and TQ crossing each other at 6k? HP is based on TQ and they always cross each other at 5,252. Something is up with how the dyno is setup...

They are two graphs from two different runs overlaid.


Originally Posted by Juiceh (Post 7385944)
Screw that! Run high boost all the time!
https://www.rx7club.com/showthread.php?t=674843

It will be a cold day in hell before any of my cars gets traction control. :)


Originally Posted by jacobcartmill (Post 7387079)
10*@13psi is very low timing. of course i'm expecting you to take this with a grain of salt, as i'm just another guy posted in your thread on rx7club, but 10* is very low timing and i'm surprised the car is running as well as it is. that probably also explains the low tq numbers.
at 13psi i'd start from about 15* and add a degree or two with the EGT gauge.
what split are you running?

I looked at the datalog last night and I'm actually running a bit closer to 13 degrees. It would have fallen to 10 degrees at about 15 PSI or so.

In my experience, bridgeports just don't respond well to lots of timing. At low loads 30-35 degrees will make a pretty decent difference in mileage and driveability, but under boost I've not really seen a lot of gain by going past 15-16 degrees. Next time I dyno the car I'll be bumping the timing a bit at low boost, though probably keeping below 14 degrees under high boost...Pump gas friendly, and all that. :)

Honestly I don't know what the split is set to. I've not changed it from Microtech's base map. Probably something I should look at, now that you mention it...

TweakGames 10-02-07 02:41 PM


Originally Posted by t04tii (Post 7385842)
Why are HP and TQ crossing each other at 6k? HP is based on TQ and they always cross each other at 5,252. Something is up with how the dyno is setup...

HP=TQ * rpm/5,252.

:Wconfused

.

Aaron Cake 10-02-07 06:00 PM


Originally Posted by TweakGames (Post 7390065)
.

See above post. The graphs from two runs overlaid on top of each other showing max torque and max HP from both runs.

Honda600rr420 10-02-07 07:35 PM

any chace someone sell a turbo kit for an na?? i am very impressed with you vid and your work wish i lived around you id like to learn a thing or many from you

Sindregutt 10-07-07 12:43 PM

Nice build Aaron cake!
Never ever think about buying a Kaaz diff :P If you do it`ll go from daily driver to trackday ONLY..
Im running a TIal wg with a .45bar spring and the profecII boost controller and it works really well.. Nice to have low power when its really wet :)

ddub 10-08-07 08:31 AM

Congrats Aaron.

Aaron Cake 10-08-07 09:53 AM

Made some 1/4 mile runs on Friday. Best run was about 13.12 @ 176 with the tires spinning 3/4 of the way down the track. Traction remains the biggest problem but at least I've got the launch figured out. I'll post some timeslips when I feel like scanning a few of them and have the video edited...

HAI-TEK7 10-08-07 10:12 AM


Originally Posted by Aaron Cake (Post 7398707)
Made some 1/4 mile runs on Friday. Best run was about 13.12 @ 176 with the tires spinning 3/4 of the way down the track. Traction remains the biggest problem but at least I've got the launch figured out. I'll post some timeslips when I feel like scanning a few of them and have the video edited...

HOLY SHNIKEYS BATMAN!! 176!!

At first i thought it was 176 MPH!!!.....had to do a double take, forgot you in Canada

Congrats on an awesome build.

FYI, 176 KMH = 109.3 MPH

PvillKnight7 10-08-07 01:16 PM

with slicks, your front diff mount is going to rip unless you weld it solid or install a pinion snubber

orion84gsl 10-13-07 05:45 PM

Everyone needs to stop questioning Aaron, he knows what hes doing, and he knows something is going to give, and he's is prepared for to deal with it. When do I get a ride in this monster?

Aaron Cake 10-20-07 07:26 PM

Here's the video from two weeks ago at the track:

http://www.youtube.com/watch?v=UOPXWf7_LQ8

Crazyness...Loosing traction in 4th gear at 170 KM/H is a bit scary...

TweakGames 10-20-07 07:34 PM

what?! that cant be right ... 13.8?!

PvillKnight7 10-20-07 09:16 PM

Shift faster! I thought your setup was supposed to be fast...

Aaron Cake 10-21-07 09:58 AM


Originally Posted by TweakGames (Post 7439970)
what?! that cant be right ... 13.8?!

Timing mistake. Seems to happen fairly often at Sparta. It's sort of funny sometimes when the numbers are totally skewed. I have some timeslips from when the car was NA that show 14.xx at 70 MPH. :)


Originally Posted by PvillKnight7 (Post 7440177)
Shift faster! I thought your setup was supposed to be fast...

The car breaks traction in every gear but 5th so there's not a lot of point in hammering the shifts. It's more then a but unnerving putting the car sideways going into 4th at ~170 KM/H, and a little unsafe as well. So until I get an LSD and some rubber it's enough just to keep the car on the track. :) The car is a mid/low 11 second car once I have traction...

TweakGames 10-21-07 06:48 PM

so aaron You have done a lot with the 6 ports now .... Would you mind if I pick you brain for a bit of what you would recommend?

I am going to be rebuilding my spare origional NA but the more I think about it the more I think of it as a re-create. Since I am going new housing and possibly new rotors if I can't find some REALLY good low compression s4 rotors, most of the important stuff is new. I am going to be using the stock turbo and turbo manifold.

Anyways I was wondering what your thoughts were on the intake. I was thinking either I could keep my port matched turbo LIM and corresponding uim and suck, or I could do a spacer like you did on your first build and run the NA lim and intake. Do you think it even matters or its noticeable? Would having working 5/6 port actuators help build boost at all at lower RPM? I will be using turbo primary ports, and na secondary + aux.

Thanks, just wondering your opinions. I am only going to be doing a street port, nothing big like yours. Although I will have a haltech.

Would you consider a street ported 6 port turbo application better or at any special advantage without the 5/6 ports over a street ported 4 port application?

ZAN_TUNING 10-22-07 02:11 AM

176 kph is only like 110 mph right? either your car is 4000 lbs or your not making the power you dyno'd.. with the little bit of spin your getting the 13.2 seems about right. i really like your setup but something is off here

gxl90rx7 10-22-07 08:09 AM


Originally Posted by Intense_Motorsports (Post 7443712)
176 kph is only like 110 mph right? either your car is 4000 lbs or your not making the power you dyno'd.. with the little bit of spin your getting the 13.2 seems about right. i really like your setup but something is off here

haha yeah its called no traction because of the n/a open diff!

Aaron Cake 10-22-07 09:47 AM


Originally Posted by Intense_Motorsports (Post 7443712)
176 kph is only like 110 mph right? either your car is 4000 lbs or your not making the power you dyno'd.. with the little bit of spin your getting the 13.2 seems about right. i really like your setup but something is off here

I have no traction until 5th gear. Watch the video and listen to the tires spin down the entire track during the last two runs. During the last run, watch the position of the car in the shadow and then in the light. Notice how it moved from one side of the lane to another? That's because I had to get out of the throttle because the rear broke free going into 4th gear. :D

Next upgrade is an LSD...


Originally Posted by TweakGames (Post 7442304)
so aaron You have done a lot with the 6 ports now .... Would you mind if I pick you brain for a bit of what you would recommend?

It would have been nice if this was posted in the proper forum, but go ahead...


Anyways I was wondering what your thoughts were on the intake. I was thinking either I could keep my port matched turbo LIM and corresponding uim and suck, or I could do a spacer like you did on your first build and run the NA lim and intake. Do you think it even matters or its noticeable? Would having working 5/6 port actuators help build boost at all at lower RPM? I will be using turbo primary ports, and na secondary + aux.
Use the TII intake.

There will be no room to use the aux port stuff unless you make a custom exhaust manifold.


Thanks, just wondering your opinions. I am only going to be doing a street port, nothing big like yours. Although I will have a haltech.
Stock turbo is way too small for a stock ported 6 port engine, let alone something with a street port.


Would you consider a street ported 6 port turbo application better or at any special advantage without the 5/6 ports over a street ported 4 port application?
More port area.

RotaryEvolution 10-22-07 03:52 PM

nice work on the setup Aaron, glad to see it finally up and running well.

just a warning at pushing 17+PSI on pump fuel, make sure you are at least running an auxiliary injectant, i'd hate to see the motor go bye bye due to detonation, especially a high compression n/a motor as the internal temps will skyrocket at those boost levels. 13PSI on that turbo is barely dipping into it's efficiency range as well, plan to have some real fun around 20PSI and grab the "oh shit" handles at 25+

for those questioning the 1/4 time, ask Aaron for his 60' times, i bet none were lower than a 2.3 second run, i had similar issues with my car and could hardly push further than a 13.2 due to wheel hop and spin. stickies and a LSD make a world of difference in 1/4 mile times.

slo 10-22-07 04:15 PM

Suspension makes such a huge difference. When my car had about 275 WHP running shitty tires with an open diff on stock cosmo twin turbo's (13b-re), I was running 14.5 with massive wheel spin through first, some in second, but nothing like whats described here.

Same power just an LSD, much better tires, fresh suspension (AGX eibach bushings nothing to aggressive), and a pinion snubber (best 10$ spent on the car) It got into the high 12's on the first and only run I made in that configuration before blowing a turbo with a still shitty 60' time.

RockLobster 10-24-07 06:42 PM

This straight line stuff confuses me.

(Nice work, that was a ton of fun to watch) :)

Shainiac 10-31-07 11:20 PM

Just an interesting tidbit, but this years Grassroots motorspors $2006 winner was a 350SBC-clad FC still using the stock NA rear and running 11s on slicks.

PvillKnight7 11-01-07 09:42 AM


Originally Posted by Shainiac (Post 7471673)
Just an interesting tidbit, but this years Grassroots motorspors $2006 winner was a 350SBC-clad FC still using the stock NA rear and running 11s on slicks.

Now thats a vid I have to see to beleive


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