Increasing Power vs. Weight Reduction
#17
My evo 7 is 2645 pd with 2 seats and a full cage. I would like to remove another 250pd but that is getting expensive. We even removed one of the firewall skins. The biggest problem I had is removing the weight evenly. You can remove plenty from the rear but it is harder at the front.
#18
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Just wanted to keep you guys in the loop with what I'm doing, though I'll probably start another thread shortly to document the changes we've made for 2009.
Just ordered the following:
Fiber Images Super - Lightweight Hood - 6 lbs. current Vis hood is 22. 16 lbs saved
Fiber Images Trunk - 5 lbs. current trunk is 22.5. 18 lbs saved
AMS 2-piece driveshaft - 14.5 lbs saved
I will also try to trim some additional weight out of the rear doors. I'm also going to tackle the ACD reservoir move next week, and I should be able to shed a heavy bracket, and put the weight in a more beneficial place (behind passenger seat). I bought a spot-weld drill bit so I may go after any additional bracketing. Short of the $$ I spent on the above mentioned parts, I'm going to see what I can pull out now in sweat equity. I'm pretty confident I'll be able to get the car near 2950 without going too crazy.
The benefit of these mods is that I can use them for all the racing I'm doing. CF doors wouldn't be rally legal, so they'd be a PPIHC item only. Based on budget contstraints, those will have to wait till next year. I'm currently trying to decide if lexan would be a good idea in our dusty environments.
Dave
Just ordered the following:
Fiber Images Super - Lightweight Hood - 6 lbs. current Vis hood is 22. 16 lbs saved
Fiber Images Trunk - 5 lbs. current trunk is 22.5. 18 lbs saved
AMS 2-piece driveshaft - 14.5 lbs saved
I will also try to trim some additional weight out of the rear doors. I'm also going to tackle the ACD reservoir move next week, and I should be able to shed a heavy bracket, and put the weight in a more beneficial place (behind passenger seat). I bought a spot-weld drill bit so I may go after any additional bracketing. Short of the $$ I spent on the above mentioned parts, I'm going to see what I can pull out now in sweat equity. I'm pretty confident I'll be able to get the car near 2950 without going too crazy.
The benefit of these mods is that I can use them for all the racing I'm doing. CF doors wouldn't be rally legal, so they'd be a PPIHC item only. Based on budget contstraints, those will have to wait till next year. I'm currently trying to decide if lexan would be a good idea in our dusty environments.
Dave
#19
Dave, Id go weight for sure. If your car is just as fast with the weight reduction as with the power increase, or even close, Id easily go with the weight reduction. As for performance, big turbo will only net you increased acceleration whereas the weight reduction will also benefit your handling and braking, oh and breaking. As you know the lighter the vehicle the easier it is to change direction. Not to mention you are lugging that weight up hill as opposed to down. As for the roadracing rule of weight. The general rule is 100 pounds = 1 second on a 2 mile road course. Of course the actual course results may vary. Id also shift as much of that weight to the back as possible like the battery if you havent already since the evo is so front heavy. I know when I corner balanced mine im 1000 for each front corner and 750 for each back.
Good luck!! Marty
Good luck!! Marty
#20
If you urethane the lexan in, it will seal perfectly. I just pushed mine into the original door strip and then sealed it. I didn't do the back window as it is qiute structural I believe. I would be keen to see how you do your pump placement. Have you considered doing it while it is on corner weight scales to chase the best balance.
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im at 2995lbs with a full tank of gas... next im going to cut out some unnecassry brackets & take out the sound deadening material on floor... then after that im doing a lightweight drive shaft & lighter front brakes....
so hoping to be down to 2950 in a couple of weeks.. then 2900 in about 2 months...
i cant believe the car was 3150lbs at last super lap battle.. i thought she was lighter for sure.
n
so hoping to be down to 2950 in a couple of weeks.. then 2900 in about 2 months...
i cant believe the car was 3150lbs at last super lap battle.. i thought she was lighter for sure.
n
#22
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If you urethane the lexan in, it will seal perfectly. I just pushed mine into the original door strip and then sealed it. I didn't do the back window as it is qiute structural I believe. I would be keen to see how you do your pump placement. Have you considered doing it while it is on corner weight scales to chase the best balance.
Probably not going to put it on the scales, since there's not much room on the passenger side. I've got the battery mounted behind my seat (full sized Optima), and our fire bottle is behind the co-driver seat, so I'll have to mount it right up against the rear seat area on the floor. My only real choice for weight balance is mount it near the trans tunnel, or out near the edge. I'll probably mount it out closer to the edge due to a need to run tubes to to the reservoir.
Dave
#23
I run a 12v 18ah dry cell. The car starts stright away even after a month. It is very light and lays on its side behind the passenger. If you run the same thickness lexan, you could cut it to match the glass and then still be able to wind it up.
http://www.performancecar.co.nz/arti...141/gallery/10
http://www.performancecar.co.nz/arti...-vii-issue-141
http://www.performancecar.co.nz/arti...141/gallery/10
http://www.performancecar.co.nz/arti...-vii-issue-141
#24
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I used to run lexan on my Mazda 323GTX, and the problem I ran into on the front windows was that dust would collect in the window seals (bottom edge of the window), and you'd get vertical scratches forming almost from the first use. Since rally guys do a lot of driving looking out the side windows, glass is probably what we'll stick with for now.
I could definately go down to a small battery, but since I can mount it low and near the middle of the car, I figure its OK to carry some extra weight. I've seen people DNF when thier charging system went out part way up the hill. I figure carrying enough spare voltage to make the whole run (with fans & water sprayers going) is a worthwile tradeoff since you only get one shot at the mountain (no re-runs, no do-overs) each year.
Dave
#25
I know all about that. I competed at the Race to the sky which Millen and Tajima both competed at. In the last year it ran, I was running my evo 1. After the qualifying on the Saturday, Tajima, Errickson and Andrew Hawkeswood in that spaceframe Evo 8 that rolled at Pikes Peak last year were in the top 3 places. I was the 4th fastest car. So with new tyres all warmed up, the boost wound up I set off only to blow an intercooler hose off on the start line!
This was a 15km sprint with no passenger to call notes. I had video footage from the previous year so I recorded notes onto an MP3 and played them back in my helmet. As I videod each run I was able to rewrite my notes as I got quicker. It worked really well.
This was a 15km sprint with no passenger to call notes. I had video footage from the previous year so I recorded notes onto an MP3 and played them back in my helmet. As I videod each run I was able to rewrite my notes as I got quicker. It worked really well.
#26
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I know all about that. I competed at the Race to the sky which Millen and Tajima both competed at. In the last year it ran, I was running my evo 1. After the qualifying on the Saturday, Tajima, Errickson and Andrew Hawkeswood in that spaceframe Evo 8 that rolled at Pikes Peak last year were in the top 3 places. I was the 4th fastest car. So with new tyres all warmed up, the boost wound up I set off only to blow an intercooler hose off on the start line!
This was a 15km sprint with no passenger to call notes. I had video footage from the previous year so I recorded notes onto an MP3 and played them back in my helmet. As I videod each run I was able to rewrite my notes as I got quicker. It worked really well.
This was a 15km sprint with no passenger to call notes. I had video footage from the previous year so I recorded notes onto an MP3 and played them back in my helmet. As I videod each run I was able to rewrite my notes as I got quicker. It worked really well.
Any idea if the ex-Hawkeswood car may be coming to PPIHC this summer?
I like what you did with your notes, that idea will come in handy if I'm ever in a single seater!
Dave
#27
I have footage but don't know how to condense it for utube. There is the rallycross track at the bottom. I lost a lot of time on here to the better handlng cars but would gain it back on the course proper. Yes it was always a bit rough.
http://www.youtube.com/watch?v=0hRxo...e=channel_page
Sorry about the camera work.
I doubt that Rostenburg will be back.
http://www.youtube.com/watch?v=0hRxo...e=channel_page
Sorry about the camera work.
I doubt that Rostenburg will be back.
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Nice vids, I checked out a few of you at other venues. The car sounds MEAN!
Bummer about Rostenburg, that was one hell of a car to watch. At least we'll have 2 great rallycrossers, Gronholm, and Tajima to watch this year, all in top-notch machines.
Dave
Bummer about Rostenburg, that was one hell of a car to watch. At least we'll have 2 great rallycrossers, Gronholm, and Tajima to watch this year, all in top-notch machines.
Dave
#29
Thanks, it sounds strong at the Ashley Forest sprint (with the downhill) It blew a turbo in the top 2 shootout. It was stronger after that but then I sold it for the 7.