i thought id have a slight chance n/a and destroy him with the juice... i was wrong. his is a 2nd gen rx7 that was a n/a, but had a turbo motor swapped in. he is also still using the n/a drivetrain. first here are his mods:

- Professionally Rebuilt Engine by Hayes Rotary with 3mm seals - about 7k miles on engine.
- Stage 2 engine porting
- Haltech E6K (includes laptop)
- Greddy front mount intercooler
- BNR Supercars Stage 1 Turbo with ported housing and manifold
- Apexi N1 single tip exhaust - lightweight and free flowing & sounds GREAT
- Greddy Profec B boost controller
- Jacobs ignition computer (for better spark)
- Apexi N1 seven point adjustable struts
- MOMO seats
- DEFI gauges
- Fluidine radiator
- Ebach springs
- Racing Beat anti roll bars
- Bonez light steel flywheel
- street/comp clutch with braided lines
- MOMO steering wheel, pedals, and shift ****
- Bonez race pipe, 2.5" downpipe
- Silver Kosei K1 17X7.5 rims
- Kumho tires
- Mazdatrix rear camber adjust.
- Mazdatrix short shifter
- Mazdatrix braided oil cooler lines
- Brembo slotted brake rotors with hawk pads
- cone intake
- 86-88 limited slip differential
- Third gen fuel pump
- Electric fan
- TurboX s BOV
- Greddy 720cc secondaries
- Clarion deck with JBL speakers
- Dyno tuned by Rotary performance
- Comes with 2 spare Potenza S02 tires

his car dynoed at 290hp at 14psi.

my car is modded nearly as much. just a 85 TPI with k&ns, ported and poilished heads (416), cam Lift .444/.444, duration @ .050 212/218 lobe separation 114, and a 110 wet shot. oh and i forgot, i had to swap the rear in it as well. it is posi and i was told it is 3.23 (not sure about that tho).

well we did quite a few runs. from a 60mph roll (hes too afraid to launch it with the n/a driveline). the first few i wasnt using the juice and he easily walked away from me when i floored it in D. main reason i didnt use the juice the first few times was i had a loose ground. then we did a few more runs. first time i passed him. then every run after that we would be equal until the car shifted into overdrive, then he walked away from me.

is this just something ill have to deal with due to gearing? that sorta makes me mad because most of the honda boys around here who have the ***** to race will only do it from a roll. so wtf do i do? i know exhaust would help a bit, but i doubt it would help as much as i need to be able to walk him once i hit OD, by then hes just shifting into 4th. so what do i do?

edit: heres the info on his trans and rearend gearing. i left out his 5th gear.
3.475<-1st
2.002<-2nd
1.366<-3rd
1.000<-4th

rearend - 4.10

 

You could suck it up and swap in a 350 maybe. With your setup you're running maybe 14s. Racing from a roll is fun if you have an engine that actually makes power above 4200rpm. You should think about chucking that awesome 52 piece tpi intake in the garbage. His car is lighter breathes better and is turboed. If he didn't walk you even when you were on the juice he must suck at tuning or perhaps his intercooler pipe blew off. Maybe he forgot to take the 2 spare tires out of the back before racing?

 

well, he had it properly tuned by a pro, he has the dyno sheets and WBO2 sheets to prove that, and no he didnt blow off his intercooler piping he held boost fine. and again, he didnt have anything extra in the truck, hell he doesnt even have a radio in his car.

 

With your mods you could see 30hp with a full 3" exhaust. The stock exhaust systems on these cars are terrible.

 

you had 2 things against you.


1. he had a lighter car

and

2. his car makes more power.



on the plus side, its a rotory, so its not like you got beat by a 1.3L piston engine...

 

Why in the world don't you have a full header-back exhaust on your car? That would make a HUGE improvement since you already have head work and a cam. With STOCK heads, peanut cam, and intake, my 305 TPI pulled past 5000RPM and actually made some power up there after I installed my SLP 1 3/4" headers and a full 3" exhaust. The TPI intake will hold you back eventually, but on a 305, you can make some good numbers at some decent RPMs with TPI and the right other parts.

I eventually swapped it to LT1 heads, intake, and a 210*/220* cam and it made all power over 3500RPM. Was quite a dog under that, but once it hit 3500, that car pulled like a freight train for an untuned N/A 305. Now that's all on a 350 with a bigger cam

The motor in your car is begging you to buy headers and a full exhaust for it. I bet you'd get a good 10-15% (or maybe a bit more) power improvement.

Also, what rear gears are in your car, and what kind of shape is that trans in? 700R4 has gearing of 3.06 (1st), 1.6 (2nd), 1.00 (3rd), and .70 (4th). My 700R4 is dying with my new engine. Ran good with the 305 because it wasn't making enough torque to hurt anything. This new motor makes too much power and my transmission is really starting to go...makes the car a lot slower than it should be.

 

It seems Shifty beat me to my comment about the exhaust. I type a little slow in the mornings up here at school sometimes..

 

yeah i know its a rotary... i have one as my daily beater.

 

duronclocker, well the exhaust was on my list of things to do, but i ran out of money. reason the heads are ported and i have a cam is because when i got the car from my dad it had leaky valve seals and it drove me nuts. this summer i decided to fix it. to me the easiest way was to pull the heads, because i didnt want to risk having a valve fall into a cylander, and if im already pulling the head, why not have it ported and polished? and since the motor was already torn down that far, why not throw a cam in there? and then the money ran dry...

the car pulls great at 3000 and above, i didnt feel it drop off until it shifter to overdrive. the tranny was rebuilt not too long ago and easily chirps the tires(255/50-16) going into second (without the juice). im not completely positive on the rear end. the last one that was in it had a pinion nut fall off and the guy i bought the one that is in there from said it was rebuilt with 3.23 gears (its a 9-bolt).

 

Hmm 9-bolt could be 3.27. If you think that car pulls above 3000RPM now, just wait until you get headers and a full exhaust on. These cars pull SO much better in the upper RPMs with headers its almost unbelievable (especially if this is your first V8 car you've driven). The stock 305 manifolds (unless an L69 originally, which yours wasn't) all suck really bad.

Figure with headers, you'll gain 30-40hp and drop a good 15lbs off the front of the car.

Next step after exhaust should be to rip that intake off and port the hell out of that plenum. There is a ton of metal to be ground away in there, and then the base. I've never looked at the stock base in terms of porting, but I hear there's lots to be done there as well. Get a set of large-tube runners or siamesed runners.

 

You'd most likely destroy him from a dig b/c thats where your power is at but from a roll he has the advantage you should expect that... And exhaust should def be your next mod... it makes a world of difference then address the tpi unit (which hates to breathe up high as im sure you already know)

 

Nice mods!


Huh, but I thought that was one of his mods.

And no aftermarket exhaust? That's the first upgrade people do.

Doesn't sound like you have a good set-up there.

"1.3 liters of fury", sounds like the title to the next "Fast & The Furious"

 

well i didnt go threw his mod list, he does have exhaust on his, it was listed. as for me, no i dont have exhaust done.

 

you can shift into overdrive at the top of 3rd?

why u going into overdrive? top 3rd is well over 115mph.. the race shouldnt go beyond that...

 

well i just got back from my first trip to the track. my first run was horrible and i only got one run in with the nitrous. right after the run with the nitrous it started porring down rain so we had to leave.i think i could have done better. tell me what you think, these are in the order i ran them:

R/T .726
60' 2.417
330 6.686
1/8 10.144
MPH 70.80
1000 13.138
1/4 15.653
MPH 89.95


R/T .648
60' 2.348
330 6.616
1/8 10.076
MPH 70.84
1000 13.070
1/4 15.584
MPH 90.00


R/T .788
60' 2.485
330 6.692
1/8 10.124
MPH 71.30
1000 13.098
1/4 15.597
MPH 90.61

R/T .539
60' 2.413
330 6.445
1/8 9.592
MPH 78.82
1000 12.253
1/4 14.481
MPH 101.46

 

that or just can't drive very well.
I agree that the gearing on N/A tranny for the rx7 sux when used with a turbo but he should still be pulling a lot better then that.

have seen a few ppl putting down that much power running well into the 13's on a rx7 granted they are using the turbo tranny which I'm sure could make quite a difference. also have seen people with quite a bit less power and they are running faster then what you ran with your nitrous.
also I would think with a decent port job and an upgraded turbo with exhuast he would be putting more power down. are you sure cyber has that car tuned to full potential?

so I'm not sure whats going on


but hey thats life and things always work out that way.
just wish I had the money time to get my rx7 back up again. stupid pulsation damper issues..

also what altitude are you at?

cause with your mods I would almost think you would be running faster also.

and are you sure you really need those 4.10's right now?
with the stock tpi intake as others have said your going to just run out of breath. car shifts takes one good breath and then gets the wind knocked out just as quick as that breath came.

as others have said full catback and headers plus get rid of the stock intake if you can or if nothing else port it out maybe to get a little more breating room in there.

 

Wow your 60' sucks might wanna take a look @ that

 

I doubt it would be that much on a basic 305, although Ive seen dyno charts of 30+ hp on mild 350s

 

WIth out the juice you are running about what a stock 85 TPI ran

 

yes my 60' sucked, i noticed that.

rx7speed, track altitude is 492ft above sea level. and i never said i have 4.10s whered you get that?

 

oops don't ask lets just say I misread something and I'm an idiot :-)

 

so do you know whos car im talking about?

oh and here are his times from when he ran his car at the track.


R/T: .201
60': 4.004
330 8.538
1/8: 11.791
MPH: 79.14
1000: 14.476
1/4: 16.723
MPH: 99.14


R/T: .950
60': 2.862
330 7.443
1/8: 10.909
MPH: 70.87
1000: 13.737
1/4: 16.028
MPH: 97.32


R/T: .406
60': 2.664
330 6.849
1/8: 9.895
MPH: 81.10
1000: 12.445
1/4: 14.583
MPH: 104.91

R/T: .824
60': 2.501
330 6.627
1/8: 9.823
MPH: 78.72
1000: 12.419
1/4: 14.605
MPH: 101.67


R/T: .114
60': 2.395
330 6.443
1/8: 9.564
MPH: 79.21
1000: 12.144
1/4: 14.326
MPH: 101.71


R/T: .517
60': 2.535
330 6.586
1/8: 9.770
MPH: 76.43
1000: 12.402
1/4: 14.635
MPH: 100.53


R/T: .1.400
60': 2.454
330 6.399
1/8: 9.352
MPH: 84.28
1000: 11.837
1/4: 13.942
MPH: 107.19

 

His 60' sucks 2... 4.000? wow

 

Holy **** 14.58 and 104.9 trap speed?

R/T: .406
60': 2.664
330 6.849
1/8: 9.895
MPH: 81.10
1000: 12.445
1/4: 14.583
MPH: 104.91

 

dude, i have no clue whats up with that

 

cyborg needs some help with driving skills there. if he just did the swap though I can kinda understand being he prolly isn't used to the car and with the N/A drivetrain I would guess he doesn't want to beat it to shreds

 

thats not true, he had a T2 and a N/A before he sold the T2 then the N/A and bought this one, he didnt do the swap himself, i know his personally and know he could never pull anything like that off on his own.

 

Scheister

What was the weather conditions when you ran your car?
I was able to pull off a 9.23 in the 1/8 mile with only a exhaust upgrade (no headers), posi unit (stock gears though) and $100 performance chip with my 305.

 

I agree with the others, those 60ft times are horrible. Describe what you do to launch the car, it looks like you are bogging bad off the line, that or spinning real hard. Fill us in and we may be able to help.

 

wow, somethings up with your 305

a few years back a friend of mine had an 85 TPI car that ran a 14.9 at 90mph with only an airfoil, the plenum ported, and a K&N cone filter in place of the airbox. then he installed a 125 shot on the car, ran some good gas, and coaxed his times down to a 13.1 at 103mph. pissed me off cause he always used to beat my 89' Vette by a few hundredths, but then again he was on N2O and i was N/A

so from a stop, your setup should beat this guy... but after seeing his 107mph traps, youve got no chance against him from a roll

 

to launch it i held the brake in and gave it as much throtle as it would take without breaking loose (around 1100prm) then i just mashed the pedal when the last yellow came on. and yes i spun the tires quite a bit

 

even from a dig the rx7 should be able to somewhat hold it's own.
with a good set of DR or even good street tires the guy should be able to pull a 1.8-1.9 60 foot I would think.
but with the way he currently is driving from a dig you should whoop is bum BAD!!!!

 

Almost got it right but not quite. First a couple pointers, make sure your tires are properly inflated(letting air pressure out of street radials is a joke). When your rolling up to the line do your best to go around the burnout box so you dont pick up too much loose rubber from the other cars, and do a SHORT burnout. Just enough to clean off the tires and heat them up just a bit. When you stage do what you were doing, left foot on the break right on the gas to load the TC. Where your going wrong is the launch itself. When you see the last yellow light let off the break, but do NOT hammer the gas keep your right foot right where it is. You will feel the front of the car jump for just a second, as soon as the front comes down ROLL on the throttle fast. Go out on a deserted country road and practice it a few times until you find the best technique for your car, you should be coming out with minnimal wheelspin, just enough to keep you from bogging.

 

Why is deflating street radials a joke?

 

My wording may have been a bit misleading but here is a brief quote

"Correctly inflated tires receive appropriate support from the contained air pressure to provide an even distribution of load across the footprint and help stabilize the tire's structure. And while most drivers recognize that this has a significant impact on tire wear, rolling resistance and durability, only a few realize underinflation also has a noticeable influence on how quickly and precisely the tires respond to the driver's input."

from here http://www.tirerack.com/tires/tirete...e.jsp?techid=2

You can play around with tire pressure a bit, but keep it within the range recommended by the manufacurer. Some morons will just take out a bunch of pressure arbitrarily until the tires get mushy and think they are going to get the best performance. With street tires you want to find the right pressure to give you the best "footprint". I tried to find a site that had a grapphic showing the difference in footprints between an overinflated tire, a properly inflated tire, and an underinflated tire but didn't have any luck, and i dont feel like drawing right now

So just to be clear let me restate, you can play around with different pressures, but dont run them underinflated.

 

That quote has nothing to do with drag racing. That's talking about lateral handling and brakeing. I don't need a drawing to understand that the less air a tire has, the larger the footprint will be. The thing you want to watch out for is the fine line between having a larger foot print, and decreasing your rolling resistance once you start moving.

 

Apparently you do, but I'm still not going to draw one. I appolagize for the size/quality of the image, but my pc is all messed up and I had to scan this in using MSPaint. It also contradicts some of what I said about trying the lower end of the recommended range. So I guess the best thing to do would be to try and get in for a test and tune where you can have unlimited runs to play around with your setup and find whats best for you. It would be good practice/tuning op for your spray as well.



EDIT: Grrrr, WTF??? Like I said my machine is messed up and I can't just click the IMG button to attach images. I used the {IMG}{/IMG} tags and it shows up as hyperlink. Any ideas??

 

I understand that, but you aren't sure where exactly that starts happening. I doubt that the inertia of a launch wouldn't be strong enough to compensate for that bulge. Ever seen a drag slick?

 

i cut a 1.89 60 foot on a stock l98 with full exhaust with 2800 stall and 2.77 gears on street tires. i ran a 2.02 60 at full pressure but didnt launch it as hard i think. next run was 1.94 and took out pressure to 24psi and ran 1.89. i run 30psi on teh street and took it down to 24 25 psi at the track. (but i doubt that 5psi makes a big difference) this is with eibach lowerin springs and NO LCA's or reloc-brackets. it would do 1.8's 60's all the time the more practice i got but i only tracked it a few times before i swapped in 3.27's. i never spun so i dont know how much more bite i had left.

with the new 3.27's i ran a 1.88 60 on 24psi with exhaust leak and bad torque arm bushing so my traction was suffered. it was also a hot day... i also had LCA's on and reloc brackets. they helped but that torque arm is so very important. i noticed a huge improvement on the street once i got i fixed. cant wait till october to get some good times


just my experience so far

 

The actual amount of friction force that is applied to the ground has nothing to do with the size of the contact patch. Increasing the contact patch only allows you to load the tire more before it "breaks loose" or exceeds the friction force. You in essence use more of the tires circumference to account for the minute irregularities on the road surface. A narrow tire won't produce the same tractive force as a wider tire over these irregularities. It will however supply the same friction force. The force is just more concentrated over a smaller area (contact patch) which will yeild itself to the limits of the tire compound. A wider tire spreads that force over a larger area thus reducing the force per unit area on the tire compound.

As mentioned above the lower the tire pressure the lower the wheel will accelerate. The It is a balancing act. Energy loss due to rolling resistance is negligable compared to the energy required to accelerate the tires. You lower the pressure so that you accelerate quicker on launch which will have a greater impact on ET's rather than having more acceleration down the strip. Therefore it is not stupid to decrease the pressure on stock tires.

 

Yes, and with that being said let's not forget all tires are not created equal.

I'm in the mood for bar-b-que squirell.......all 1.3 litres of it

 

I know why his 60' ft and 1/4 mile times seem weird. Look at mine in my sig. His drivetrain is mismatched like mine. With that cam and a stock TC he isn't making any power until 3000rpms. I'm surprised he can spin the tires at all, let alone chirp 2nd. And if those gears aren't 3.23s and are lower, then that is an issue too. A higher TC and full exhaust should be your next mods. You could drop up to a second in your times. Try your best to find out exactly what gears you have or get new ones.

~Matt

 

Oh and I forgot one important thing. With your ported heads and cam, you MUST shift manually because most of your power is above where the auto will shift. My 305 screams all the way up to 6500rpms. If you let the tranny shift itself you will shift while still making a lot of power. You'll end up in the next gear at low rpms where your power is less. I ran my time in my sig shifting out of 1st at 6250 rpms at 50mph. I hit the end of the 1/4 mile still at the top of 2nd (about 6500rpms). Needless to say, I need a higher stall and gears too. Too bad that takes money.

~Matt

 

Tell me you rebuilt that bottom end for high RPM stuff. I put ported LT1 heads, LT1 intake, and a 210/220 cam in my 305 and it threw a bearing first time hitting 6300. It'd been to 6000RPM a decent amount, but as soon as my trans didn't shift perfect the one time, she started knockin. Drove it a half hour back to Nick's house, and trailered it home. Tore the motor apart and found I spun 3 rod bearings. Supposedly the 355 I have now is good til like 7200RPM or something crazy like that. Haven't gotten the tuning down yet, so I'm not sure how high its going to make power. Probably til 6200RPM or so. Ported LT1 heads, intake, 224/230 cam, SLP 1 3/4" headers, etc. Won't find out what she can do til I get a new trans in (stick!) and learn how to drive it right and get it tuned.

 

I like how 7200 rpm is "crazy" on your guys cars.

 

hey it's higher then my stock redline by 200rpms for the mazda
but hey sad thing is their cars have a higher redline then my honda at a measly 5500rpms I think?

 

It's higher than the current POS that I drive as well...

 

No I didn't do anything to the bottom end. I bought the car for $800 with a blown head gasket and only running on 6 cylinders. Me and my buddy and his dad tore the engine down to the top of the heads. There was coolant on the top of the 5 and 7 cylinders so we cleaned everything. Ported the heads a little, 3 angle valve job, threw in a new cam, put on headers, cleaned out the intake and tuned the carb. The motor had 175,000 miles on it when it ran the times in my sig and never had a problem hitting 6500rpms. Maybe because its carbed? I don't really know, but now i'm saving up for a new motor because its not worth it to keep building up a 180k mile 305.

~Matt