280zxt CHUMP CAR BUILD

[RAG&BONE]

From Drop Box">

So I dont know how many of you guys have heard of "CHUMP CAR" before but basicaly it is a racing series that races all around the country at some of the best tracks , this summer they are racing the new Spokane track in july and that will be our first outing with the car. What makes it awsome is that you can race these epic track in whatever beater you want as long as its under 500 in value. I have decided to build a 1981 280zxt , I picked this up from a old timer in Grahm WA for 400. Me and my team RAG&BONE motorwerks out of Tacoma have been tearing her down to make it as lean and fast as possible.... on a limited budget of mostly junk yard parts.

To give us a fighting chance we have upgraded the brakes up front, using 84 300zx front struts and steering knuckles this let us get almost 11 inch rotors, then we upgraded to infinity j30 2 piston calipers.

From Drop Box"> The camber angle of the 300 zx is different than the 280 zx but its not to terrible, if we drop the front all the way down it puts us at almost nuetral camber, a little tweeking and we ahould be able to get some proper geometry :D . Also we have switched to the Z31 engine managment to give a bit better drivablityThe car came with a auto trany so we swaped in a 2+2 flywheel(240mm instead of 225mm) and 5 speed trannyWe have to run a full cage, between that and the solid motor and trany mounts she is going to be one stiff ride. we have shaved a TON of weight out of the car, we are hoping to get the actual race weight to be around 2400lbs with about 215hp.

From Drop Box"> That will give us a pretty good power to weight ratio. We are also planning on putting the boost up to about 10psi and running a intercooler , along with a custom made(fiberglass and cardboad) front airdam/splitter for better air flow and cornering. Also guna make a rear whale tail wing out of a old datsun tail gate ( we are level 4 recycling ninjas)

From Drop Box">

;) We have done coil overs on all 4 corners since this picture was taken.

So basicaly my reason for joining the forum and making this post is to see if any one has any tips from there Z car Experiance that they would like to share with me as to any weak areas of the car I should address or tip to make it handle better, any info that would help the car to last 24 hours !!! Figured I know a few guys on this forum and have seen some of the builds done , you guys seem like like some crafty SOBs so I welcome any ideas . would also like to know who I talk to about gettn Ratsun.net as a sponor!

[izzo]

that tail gate wing will add at least 34 1/2 HP. This reminds me of a thread called clown shoes. Cool none the less, good luck on the race. Keep this thread updated.

[]2eDeYe]

Can't wait to see where this ends up. Any more specifics on Chump Car racing?

[RAG&BONE]

Well the car from the factory had 50/50 weight balance (which iam sure we totaly F'ed with all the crap we pulled out,) but we are :Ponly using the out side skin of the tail gate and we are ok with a little extra weight in the rear it should help.

 

And as far as more info on CHUMP CAR,you can go to forum.chumpcar.com or www.chumpcar.com to read the rules, its pretty awsome. Basicaly they love home made crazy build and hate guys that try and "buy" speed( they get penalty laps for having fancy non- junk yard parts :P )

[Rustina 510]

that tail gate wing will add at least 34 1/2 HP. This reminds me of a thread called clown shoes. Cool none the less, good luck on the race. Keep this thread updated.

 

 

Lol that thread is not fun, clown shoes should be locked

[Laecaon]

Lol that thread is not fun, clown shoes should be locked

 

first of all, it is locked...

 

 

I like this build! Looks like a lot of fun. Did you happen to see Hotrod magazines article on when they took did cheap mods on a late 80s vette? Basically stripping certain panels, and other things, changing tire pressure and stiffening the suspension they made the car come alive (shaved a few seconds off the track time). The car did look ugly as sin though...

[Skib]

We are also planning on putting the boost up to about 10psi and running a intercooler

 

your max boost with a J-pipe is 10psi.

 

your injectors can take up to about 14psi.

up the injector CC and the T3 on there can put out about ~16psi effectively

 

the 300ZX Z31 T3 center housing is also interchangeable with the 280zx exhaust housing.

you can get a bit of a cooling bonus with that because its both oil cooled and water cooled

while the 280ZX T3 is only oil cooled.

 

and after a few hours that fuckers gonna start putting off some serious heat.

 

the safety pop off valve on the stock intake is set to blow all pressure at 9psi, shim or plug that

 

So basicaly my reason for joining the forum and making this post is to see if any one has any tips from there Z car Experiance that they would like to share with me as to any weak areas of the car I should address or tip to make it handle better, any info that would help the car to last 24 hours !!! Figured I know a few guys on this forum and have seen some of the builds done , you guys seem like like some crafty SOBs so I welcome any ideas

 

the 280zx was made as a GT car, from the factory there heavy, have sloppy body roll and the rear squats like a mother fucker.

 

theres alot of ways to save weight but getting it down to 2400lbs is going to be real challenge, esp when it has a full cage in it

 

 

would also like to know who I talk to about gettn Ratsun.net as a sponor!

 

what exactly dose that entail?

[Laecaon]

I like this build! Looks like a lot of fun. Did you happen to see Hotrod magazines article on when they took did cheap mods on a late 80s vette? Basically stripping certain panels, and other things, changing tire pressure and stiffening the suspension they made the car come alive (shaved a few seconds off the track time). The car did look ugly as sin though...

 

maybe they removed more than a few panels...

 

http://www.hotrod.com/projectbuild/hrdp_1011_corvette_hack_track_test/index.html

[bananahamuck]

Skib you do understand that this car if it finishes will be virtually destroyed ,,,,,,,,right ??

 

check out 24 hours of lemons as an example .

[]2eDeYe]

would also like to know who I talk to about gettn Ratsun.net as a sponor!

 

I could send you some stickers :D

[RAG&BONE]

your max boost with a J-pipe is 10psi.

 

your injectors can take up to about 14psi.

up the injector CC and the T3 on there can put out about ~16psi effectively

 

the 300ZX Z31 T3 center housing is also interchangeable with the 280zx exhaust housing.

you can get a bit of a cooling bonus with that because its both oil cooled and water cooled

while the 280ZX T3 is only oil cooled.

 

and after a few hours that fuckers gonna start putting off some serious heat.

 

the safety pop off valve on the stock intake is set to blow all pressure at 9psi, shim or plug that

 

 

 

the 280zx was made as a GT car, from the factory there heavy, have sloppy body roll and the rear squats like a mother fucker.

 

theres alot of ways to save weight but getting it down to 2400lbs is going to be real challenge, esp when it has a full cage in it

 

 

 

 

what exactly dose that entail?

I know using a intercooler is a bit over kill with only 10-12 psi but i figured it would help in a 24 hr senario, is there a stock injector out of another car that would be a good upgrade, and if i do bigger injectors and 14psi will the z31 ecu map beable to handle it?

 

the cage is only about 80 LBS, and we have put new stiffer spring rates and gabriel ultras( these have metal valve bodies instead of plastic like most mid grade suspension) on all 4 corners, if nesaccary we will go with all poly bushings. one other thing i forgot to mention is we welded up solid motor and trany mounts also.

[RAG&BONE]

2eDeYe' date='29 April 2011 - 10:29 AM' timestamp='1304101791' post='467667']

I could send you some stickers :D

 

If you can do a ratsun windshield banner that would look mean as hell!!

[RAG&BONE]

maybe they removed more than a few panels...

 

http://www.hotrod.co...test/index.html

 

 

chump car has a rule "must have 50% of the original body" they look like about 30%.. maybe,haha. other than that it looks like it could make a good chumpcar, that is if you could prove that a corvette is a 500 dollar car....

[h4nsm0l3m4n]

I'm on a team that has run a Rx-7 in a few of races in Portland and also last year in Spokane. There were plenty of datsuns running including at least 1 or 2 280zx, they do pretty well.

 

I dont know if this is your first time or not so sorry if you are already aware of what I'm posting... One thing to keep in mind is that its a endurance race. 24 hours of pounding on the track is a long time, so I am always one to argue for leaving it stock. Dont wear out your motor unnecessarily, an extra few horsepower wont really make a difference, your driving skills and car's reliability will. Lots of cars (including ours) fell out of the race and didnt finish. I would advise that if youre going to build a motor build it to be reliable and not fall apart mid-race. Engine swaps at the track are stressful. Keep it simple, dont get too crazy with your car and do a lot of testing before the race.

 

Also the race is for cars "valued" at $500. This doesnt mean just because you bought a car for 400 bucks its "valued" at $500. Intercooler, coilovers, other mods all add value to the car (brakes and safety items dont count). The tech people may opt to give you penalty laps so if youre serious about winning (which you shouldnt be, its all for fun) youll be starting with a disadvantage that is hard to overcome. Have fun and dont take it too seriously :)

[RAG&BONE]

what exactly dose that entail?

 

 

Well we would love to rock some big ratsun stickers on the car and whatever support that could be offered would be accepted with much appreciation, (basicaly we have 90% of what we need to finish the car, right now we are looking to get some sponsors for tires and gas, or anything else :) ) PM me if you want to . We have a well preped team with some expirenced drivers, we are aiming for a top 10 finish

[RAG&BONE]

 

Also the race is for cars "valued" at $500. This doesnt mean just because you bought a car for 400 bucks its "valued" at $500. Intercooler, coilovers, other mods all add value to the car (brakes and safety items dont count). The tech people may opt to give you penalty laps so if youre serious about winning (which you shouldnt be, its all for fun) youll be starting with a disadvantage that is hard to overcome. Have fun and dont take it too seriously :)

 

 

I know, i have AIV documentation that puts the car at 241$ so we have some wiggle room. the shocks are oem so they are ok no real added value, brakes are exempt, coil overs are ebay crap so they will maybe ad 50-75 the ecu wil maybe add 50 tops, intercooler is junk yard so 15$. I have done my homework. ;)

[RAG&BONE]

 

the 300ZX Z31 T3 center housing is also interchangeable with the 280zx exhaust housing.

you can get a bit of a cooling bonus with that because its both oil cooled and water cooled

while the 280ZX T3 is only oil cooled.

 

and after a few hours that fuckers gonna start putting off some serious heat.

 

the safety pop off valve on the stock intake is set to blow all pressure at 9psi, shim or plug that

 

 

 

Also we are using a n47(260z?) intake manifold so we have no emission crap( or the stock pop off valve), we are running a external waste gate(junkyard volvo set up)

We have swaped out the center section like you mention so we can have a water/oil cooled set up to help with the heat.

[h4nsm0l3m4n]

I know, i have AIV documentation that puts the car at 241$ so we have some wiggle room. the shocks are oem so they are ok no real added value, brakes are exempt, coil overs are ebay crap so they will maybe ad 50-75 the ecu wil maybe add 50 tops, intercooler is junk yard so 15$. I have done my homework. ;)

 

Awesome :) Were running ebay coilovers with OEM shocks as well, seem to work decent enough. Build that motor right the first time, weve blown a motor at every race so far. Pretty frustrating when we see the same RX7s hammering on and on and on... Were going to spend some extra effort this time around to make sure it goes together perfectly. Good luck, I'll be watching your build. See you in Spokane :)

[RAG&BONE]

Awesome :) Were running ebay coilovers with OEM shocks as well, seem to work decent enough. Build that motor right the first time, weve blown a motor at every race so far. Pretty frustrating when we see the same RX7s hammering on and on and on... Were going to spend some extra effort this time around to make sure it goes together perfectly. Good luck, I'll be watching your build. See you in Spokane :)

 

 

Is your car the one on www.roadtochumpcar.com?

[h4nsm0l3m4n]

Yup

[RAG&BONE]

Yup

 

 

:lol:haha your car is cursed !, L28e is a pretty good engine, i havnt tore it all the way down to the crank but our car had a auto in it (5 speed now) with only 150xxx on it so i dont think it was beat to much during its life.

[h4nsm0l3m4n]

:lol:haha your car is cursed !, L28e is a pretty good engine, i havnt tore it all the way down to the crank but our car had a auto in it (5 speed now) with only 150xxx on it so i dont think it was beat to much during its life.

 

Haha, yeah it really is! We've had pretty much every kind of engine seal failure one could have in a rotary, its pretty amazing. Now that the chassis is all sorted out we've got so much more time to get the motor right. New motor is going to be awesome! Its also going to be my first 24 hour race, I'm pretty excited

 

We're pretty lucky with the Datsuns, the engines seem to hold up great. There were 2 S30s, 1 or 2 S130s and a Roadster at the PIR race last month, all but 1 finished (FWIW the one that didnt ran a V8 :) ).

[RAG&BONE]

Haha, yeah it really is! We've had pretty much every kind of engine seal failure one could have in a rotary, its pretty amazing. Now that the chassis is all sorted out we've got so much more time to get the motor right. New motor is going to be awesome! Its also going to be my first 24 hour race, I'm pretty excited

 

We're pretty lucky with the Datsuns, the engines seem to hold up great. There were 2 S30s, 1 or 2 S130s and a Roadster at the PIR race last month, all but 1 finished (FWIW the one that didnt ran a V8 :) ).

 

Yeah dont think I havnt been keepn track! this year there has been a z with a L28 motor in it at just about every race and they usualy do well. we are doing spokane and portland this year car 79, come say hi if you see us!

[]2eDeYe]

If you can do a ratsun windshield banner that would look mean as hell!!

 

I might actually be able to do that :)

[RAG&BONE]

I can give you measurements if you need them, big ratsun rising sun about 8inches tall and streach across the windshild would be very nice touch