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ibaker:

Crosser1:

ibaker:

Mike Shields:

Ian, you know you want it... it's calling you... of course you'll need to make new full wheel tire blankets

 

mmmmmm 15in Jiffy Pop.

Ian 

I hear it need 10" of plexiglass just to get enough heat to pop though. 

 Eric

 

Hahahahaha, I forgot to put the silver foil on the plexiglass so it didn't concentrate the solar rays and warm up the tires :)

So Nate, what would it take for me to borrow your set of 15's for a day to do some testing on my CSP car???? Maybe I should bring both cars up for the Devens Tour?

Ian 

Are you putting 5-lugs on that rex?

You need to call me Ian. Uber top secret, unable to post it anywhere live.

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Nate Whipple
NER
188/88 DSP ITR

Tons of progress this weekend. Clutch is done, as is some of the wiring that I had to clean up after removing the old alarm. The car actually ran again today. I also got my junkyard fenders and finished sanding off the original green paint from one of them. I've got a guy lined up to open the hub bore on the wheels and the steering wheel is ordered. I'm pretty sure I've decided on the header, just need to check a couple more things on it. Once the hub bore is opened up on the wheels I'll get the front tires mounted so I can figure out how much clearancing of the fenders I need to do.

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Nate Whipple
NER
188/88 DSP ITR

When's the scheduled debut? Will it be here for the DC pro?

One of the many things on my list is a DSP celica GT-S.....but that's low enough it probably won't happen haha.  It would be plenty lighter than your car with similar power, just inferior suspension.  <shrug> 

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1991 Saturn SC-226k miles- HS #106
1990 Miata- Blue, with black spots- daily

MTBGAEL:

When's the scheduled debut? Will it be here for the DC pro?

One of the many things on my list is a DSP celica GT-S.....but that's low enough it probably won't happen haha.  It would be plenty lighter than your car with similar power, just inferior suspension.  <shrug> 

If by plenty lighter you mean ~25lbs, then sure.  You do know what a 97-98 DS ITR weighs, right?  Then subtract for the DSP goodies...

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Todd
Too many ST cars

"Restricted Area Racing"

The 'barely' STS (sway bars, shocks, heavy wheels and exhaust) celica GT I drove was mid 2300's.  DS ITRs are high 2500's/2600s IIRC.  That puts the celicas at least 200lbs lighter by my math...and then there's the whole 'the weight's not coming off as fast as I thought' thing.  All celicas had a/c, nice radios, etc...where some ITRs didn't have A/C from the factory.  I'd bet going to *sp trim cuts more weight off of the celica than the ITR, aside from the fact that the celica is lighter to begin with....

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1991 Saturn SC-226k miles- HS #106
1990 Miata- Blue, with black spots- daily

DS ITR's are closer to lower 2430's on Heartland Park scales.  I bet you could get a DSP ITR down to high 2100's with some tedious work on nuts and bolts and trim.

 

Chris

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Chris

Chris Kline:

DS ITR's are closer to lower 2430's on Heartland Park scales.  I bet you could get a DSP ITR down to high 2100's with some tedious work on nuts and bolts and trim.

Chris

High 2100's? That would take a LOT of work. Maybe if you started with a 94 RS shell and kept the 4-lug brakes. Even then, getting to the low 2200's would be a stretch.

The car makes it's debut in April. It'll be ready for the DC Pro barring me breaking anything expensive.
 

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Nate Whipple
NER
188/88 DSP ITR

MTBGAEL:

The 'barely' STS (sway bars, shocks, heavy wheels and exhaust) celica GT I drove was mid 2300's.  DS ITRs are high 2500's/2600s IIRC.  That puts the celicas at least 200lbs lighter by my math...and then there's the whole 'the weight's not coming off as fast as I thought' thing.  All celicas had a/c, nice radios, etc...where some ITRs didn't have A/C from the factory.  I'd bet going to *sp trim cuts more weight off of the celica than the ITR, aside from the fact that the celica is lighter to begin with....

DS ITRs are definitely lighter than 2600lbs--even 2500lbs.

I know for a fact an ST-prepped ITR can be at 2400lbs or less.  In DSP it'll be lighter than that, I guarantee you.

 

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Todd
Too many ST cars

"Restricted Area Racing"

solo-x:

Chris Kline:

DS ITR's are closer to lower 2430's on Heartland Park scales.  I bet you could get a DSP ITR down to high 2100's with some tedious work on nuts and bolts and trim.

Chris

High 2100's? That would take a LOT of work. Maybe if you started with a 94 RS shell and kept the 4-lug brakes. Even then, getting to the low 2200's would be a stretch.

The car makes it's debut in April. It'll be ready for the DC Pro barring me breaking anything expensive.
 

A 4-lug setup gets rid of a ton of weight...

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Todd
Too many ST cars

"Restricted Area Racing"

I'd go 4-lug if I wasn't concerned about axle longevity.

My car weighed 2640lbs at HPT when I first got it. 16" wheels, full exhaust, amp and sub, spare/tools, a/c, full stereo, and a half tank of gas.

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Nate Whipple
NER
188/88 DSP ITR

You're going to go through a few axles anyways...and some of this depends upon what diff you run too.

But if you don't run it at pros, I think with either 4 or 5 lug the axle-shredding will be minimal.

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Todd
Too many ST cars

"Restricted Area Racing"

tkm:

You're going to go through a few axles anyways...and some of this depends upon what diff you run too.

But if you don't run it at pros, I think with either 4 or 5 lug the axle-shredding will be minimal.

I'll be running it at Pro's, but for now I'll stick with the stock diff. I need to pick up a spare set of axles to bring with me, just in case, but I'm hoping with the 5-lug setup and the OEM diff that the car won't be TOO abusive to the axles. 

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Nate Whipple
NER
188/88 DSP ITR

I don't think it'll matter if you're running pros because you will frag an axle sooner or later using those tires (and since you're on an upgraded clutch now). Did you do the lightweight flywheel?  If not, it is highly recommended from the R's I've drove with one.  6lb comptech--OMG!

As for a diff...I highly recommend a good 1.5way clutch type.  It'll make a difference, even with the tire width you'll be running.  It just changes the way the car corners, in a big (and positive) way.  Don't waste your time with a Quaife.  It's better than OEM, but not by enough.

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Todd
Too many ST cars

"Restricted Area Racing"

tkm:

I don't think it'll matter if you're running pros because you will frag an axle sooner or later using those tires (and since you're on an upgraded clutch now). Did you do the lightweight flywheel?  If not, it is highly recommended from the R's I've drove with one.  6lb comptech--OMG!

As for a diff...I highly recommend a good 1.5way clutch type.  It'll make a difference, even with the tire width you'll be running.  It just changes the way the car corners, in a big (and positive) way.  Don't waste your time with a Quaife.  It's better than OEM, but not by enough.

Stock clutch and flywheel for now. Keeping my options open in case I need to bounce back to stock.

No plans for a diff change because I'm not certain it is needed yet. I like the seamless action of the factory torsen and like you said, the Quaife isn't enough better to warrant replacing the factory diff with a Quaife. I'm going to be data logging RPM and using a math channel I can compare wheel speed to GPS derived vehicle speed. There is a certain amount of error with that method, which I'm willing to accept. That information plus lateral acceleration information will be more then sufficient to figure out if I'm getting wheel spin of a magnitude large enough that a diff change could be beneficial. That is all second year development material. First year I just need to get the thing to handle well with decent power while being fairly light and reliable. Besides, compared to an open diff, that factory diff is absofugginlutely brilliant!

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Nate Whipple
NER
188/88 DSP ITR

Wheelspin won't be a huge problem with the 275 tires with the oem diff.  But, a 1.5way clutch-type diff will transform how and where the car puts its power down and how soon you can get on the gas.

And yeah, an upgraded flywheel is a must.  If you get serious about DSP, it should be on top of your list.  Stock clutch will be fine.

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Todd
Too many ST cars

"Restricted Area Racing"

Steering wheel is in, dash is back together, wheel bore is corrected, prep on the junkyard fenders has begun. If I hang the fenders and put the nose back on, the car is drive able. Not quite ready to compete, but drive able...
 

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Nate Whipple
NER
188/88 DSP ITR

Nate, check PM

Allen

Tires mounted. I decided to go 9.5" on the wheels when I put them back together. Keizer doesn't have a hub and wheel half combination that gives a true 15x10 with the backspace I wanted. So what they do instead is put the wheel center between the wheel halves. This adds the 3/8" of the wheel center to the overall wheel width which starts at 9.5". So the end result is a wheel that is 9 7/8" wide. However, when you look at how the wheel is assembled, on the back side of the wheel there is a bolt plate that takes the abuse of the fasteners off the wheel half. It's there for a reason. However, when assembled with the wheel center between the wheel halves, there is no such bolt plate for the outer rim half. Typically the 3/8" thick wheel center takes that abuse and keeps the mating surface of the outer rim half healthy. Also, when assembled for the extra width, you now have two seams that could potentially leak. I decided to err on the side of strength and reliability and assembled the wheels with the rim halves together and the bolt plate plus wheel center as the sandwiching bits. This also makes the front of the car 3/4" narrower. With the tires mounted, the side wall is still quite square. Maybe a tiny bit of pinching. At any rate, the wheels go on the car this weekend and the fender modifications begin.

I've got a header on the way now, not the one I wanted, but one I could afford. Also looking at a new approach to the intake side of things. If internet dyno's can be trusted, intake, header and exhaust combined with some tuning should produce enough hp to walk the best Bavarian box. Too bad it comes with "nice try" for a torque number! Down shift FTMFW!

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Nate Whipple
NER
188/88 DSP ITR

Fenders fit now. Working on prepping them for paint. Damn if these tires don't leave any room for anything else though. They do clear all the hard points from full lock to full lock at an absurdly low ride height, which is a good thing and huge relief. I'm seriously contemplating bumping the front spring rates some more to be safe. I could run it higher too, but I don't like the bind issues offset delrin bushings introduce so I'd have no way to get back the camber I'd loose. Currently, I'm 4" from ground to jack tab up front, and 3 7/8" to the rear jack tab. I'll give it a shot at this height and see if it works.

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Nate Whipple
NER
188/88 DSP ITR

solo-x:

If internet dyno's can be trusted, intake, header and exhaust combined with some tuning should produce enough hp to walk the best Bavarian box. Too bad it comes with "nice try" for a torque number! Down shift FTMFW!

OK, so while you concentrate on shifting, I'll concentrate on cornering :P

Once I get the head back on the car and get it off to the dyno for tuning, we'll have to compare dyno charts to see just what the area under the curve is.

-Mike

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Mike Shields
1993 BMW 325is | 92/192 DSP