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Discussion Starter #1
Ok here's the story. I was on the dyno the other day and laid down 463.6 at 1.1 bar before the clutch failed. Now those numbers are at 6200 rpm and the way the curve was, maybe I would've seen 467-470 if the clutch would've held. What can I do without adding more fuel that will get me to 500 rwhp? I have a T-78 w/stock fuel so turning up the boost is out of the question. I have the RPS stage 3 sprung hub w/ lightened flywheel sitting on the coffee table and have the twin electric fans on the way. Will these free up any signifigant hp? I want to reach the 500 rwhp goal before upgraded fuel, boost increase, cams, and such.

A short list of mods:

Blitz DSBC
Rod Millen DP
Tanabe Racing Medallion Exhaust
Apexi FMIC
VPC
S-AFC
JUN cam gears
HKS timer
T-78 kit w/Greddy Racing BOV

Any suggestions on freeing up some hp?

Eric

500 rwhp w/ stock fuel and 152500 miles? Now that's a goal.
 

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FWIW,
My understanding is that the TRD twin disk clutch frees up approximately 15rwhp across the entire powerband (due to the lighter rotational mass of the flywheel). It's pretty likely that you will see similar gains with the RPS unit (for the same reason).

FYI,
Kelly
 

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He already has RPS Stage 3 clutch with the lightweight flywheel and should be installing it soon.

The carbon fiber driveshaft might free up some hp due to it's light weight, but is by no means a cost effective method of increasing HP. I think it retails for $1K or so?

I don't think he would see much of a gain (if any) from the pulley set unless he were to include the Underdrive Pulley. I think the collective thoughts on the MKIV list are that the increase in HP doesn't justify the risk of damage to the drivetrain. :(

Not saying that you are incorrect in your recommendations (you're not), but I personally wouldn't take that route.

Just my .02,
Kelly


Suprascene.com said:
Yea well why not just purchase a lightweight flywheel, carbon fiber driveshaft, and UR pulley kit..
 

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Well my friend just installed the UR pulley kit in conjunction with the composite driveshaft and found the dampening effect greater than over stock. Basically I never thought UR would make an item bad for a car, but now I look at it like a clutch. If you want the performance the ride is a bit rougher... even like suspension. Anyhow he's only BPU + whatever and I haven't gone for a ride but from what I hear he's spooling much quicker now and that dampening effect was a major factor and he's very pleased with the outcome.. I hope to follow in his footsteps when I get back home, the composite driveshaft seems to be becoming a trend.
 

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Um yeah, or he could spend the money he would have spent on the carbon fiber driveshaft on fuel mods, and he would make much more power :rolleyes:

An underdriven crank pully has be associated with problems ranging from crank position sensor failure to crankwalk. It has nothing to do with dampening acceleration of the crankshaft, it dampens vibrations of a certain frequency. There are very detailed links about it in the tech section of MKIV.
 
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Discussion Starter #8
I talked to Nero the other day and they're testing out a new dampend underdrive crank pully on Nero's personal car. I'll be interested in the results. I'm having the clutch/ lightened flywheel installed this weekend and also decided to install the electric fans. That should free up a few ponys. I bought both EGR plates as the mod was done but the plates weren't installed. I think the carbon fiber driveshaft is only 2 or so pounds lighter than stock, and I don't light off any 5000 rpm launches, so I think thatit's going to wait. My goal, as yuo can tell by my sig, is to reach 500 rwhp on stock fuel. It may be a silly goal considering if I just saved for a fuel system I could get a lot more output, but I figure if I can get 500 rwhp with stock fuel (152500 mile old fuel injectors and pump) and 1.1 bar, then 650 isn't far away with a stage 2 fuel system upgrade, pwrhouse racing cams (272,272 or equivilent), rev upgrade to 8000 rpm, and boost cranked up. Keep the ideas coming, please. I'm sure there are plenty secrets that the community has for inexpensive hp.

Eric

T-78, 500 rwhp w/stock fuel and 152500 miles? Now that's a goal.
 

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I wouldn't get electric fans, many people have had cooling issues with them and FMICs, even during street driving. AFAIK you pretty much can't road race w/ electric fans.

The stock fan is on a clutch, so I don't think it takes too much HP to run. I know a guy who had electric fans installed by Titan, when he got an Apex FMIC his coolant temp would rise going WOT during street driving.
 
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Discussion Starter #11
You can do some minor fuel modifications.

Get the BD Fuel Pulsation Dampener bypass. Suposidly this frees up some fuel, but I really don't know how much.

I also upped the voltage to my fuel pump from 12v to 18v. This, also, is supposed to help, though I don't know how much.

I'm fresh out of ideas. I am also looking for a cheap alternative to getting a full fuel system.

Cheers.
 
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Discussion Starter #12
My friend, you must have been reading my mind. I thought of the fuel pump idea today while at work. I guess the B and M ignition system is on the list for installs. I think it'll be as a safety measure, though. Around 6000 RPM, the Air/ Fuel ratio is hard to keep healthy. I looked up the BD Fuel Pulsation Dampener Bypass the other day and didn't come up with much info. Is it a kit that I could purchase or is it a list of parts to be purchased separately? Supposedly the B and M ignition system can be pushed up to 30 Volts. I think the fuel pump would crap out at that voltage.

Eric

T-78, 500 rwhp w/stock fuel and 152500 miles? Now that's a goal.
 
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Discussion Starter #13
Yeah, the B and M Power Plus is for sale at MVP. It can push up to 30v, but I wouldn't reccomend it.

You can also get the Fuel Pulsation Dampener Bypass through Dusty at MVP. I think its around $100.

Be careful what you get through Nero, he's had some pretty shady business in the past. Go to Dusty at mvpmotorsports.com.

I am also thinking about upgrading my fuel pump. There is some kind of Bosche OEM pump that pushes a hell of a lot of fuel at a hell of a lot of PSI. Also, it uses less power than the stock pump. I will be evaluating this when I get back to Gainesville.

I would do as many fuel modifications as possible. A T78 on stock fuel is definatly not reccomended. One boost spike and, <BOOM>, there went your engine.

Cheers.
 
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Discussion Starter #14
carcnoid, do you know which Borsche OEM pump pumps more than stock pump?
 

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Suprascene.com said:
New ACPT is 4.5 pounds lighter and the PHR one is 1-2 pounds lighter.

And that dampend underdrive crank pully sounds like a nice investment ;)
How do you know the new ACPT is 4.5lbs lighter than stock? Is that for a 6-speed? My driveshaft weighs 20lbs and when I call ACPT they don't really know how much theirs weighs exacly...they just say it is only going to be about 2lbs lighter than stock, and that is just a guess. Do you have one that you weighed? Thanks.
 

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A while ago I emailed Ken Henderson he posted those statistics on to4r.com where they can be found. He told me a while ago but I found it was 4lbs. not a big dif but different at that.
 
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Discussion Starter #17
there was just a thread a few days ago about an electric water pump made by a company named meziere. in that thread someone posted that they seen a gain of 18 horsepower from this electric pump. i don't know how many amps it draws but i'm sure it wouldn't be that hard to find out. not very expensive either, seen it for $ 337 dollars. do a search for this thread for more info.
 

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Speaking about water pump there are some radiators that have water pumps built in if you don't have one already.. Good company from what I remember offical of nascar like C&R or something..
 

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I have the Flexalite electric fans and have had no problems with over heating. I have the Buschur FMIC which uses a Spearco core. I rarely turn my fans on. I can sit in a drivethough for ten minutes and my temp gauge doesn't budge. I know it's not the most accurate gauge in the world, but I have seen it move higher than normal. If people have overheating problems riding around town, something is wrong with their radiator, or their FMIC is very very restrictive. I'd go for it.
 

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Jade Supra said:
I have the Flexalite electric fans and have had no problems with over heating. I have the Buschur FMIC which uses a Spearco core. I rarely turn my fans on. I can sit in a drivethough for ten minutes and my temp gauge doesn't budge. I know it's not the most accurate gauge in the world, but I have seen it move higher than normal. If people have overheating problems riding around town, something is wrong with their radiator, or their FMIC is very very restrictive. I'd go for it.
When did you see the temp gauge move higher than normal? I have never seen mine move higher than normal...there is probably a 40 degree increase that has to be seen before it even budges or something like that.

I have the stock cooling system.
 
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