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krustindumm
01-29-2010, 10:59 PM
I haven't been able to find this stuff, but I don't really know where to look. I'm trying to figure out what car to go with, what I'm looking for is power:weight, emphasis on light-weight, solid rear axle, good front suspension, cheap. If you know this stuff, or know where I can find it, I'd appreciate it.

Spindle dimensions on the Fox body, SN95, camaro, s10, g-body, basically anything RWD with a smal block V8, or V6, can be converted tocarb, and can be tuned to 0.75hp/lb (for just the engine/trans) with stock internals (bolt ons only). Spindle dimensions (ball joint/tie rod/wheel mounting surfaces, & angles relative to each other). Axle width (wheel surface to wheel surface), stock LSD availability. How much do the transmissions weigh?

V6's are great, they're shorter & lighter. Lighter is always better. I'm not concerned about the chassis at this point. Just the drivetrain. I'm considering a liter bike engine, and those are around 1hp/lb and are easy to find for under $1000, and I can find wrecked cars for under $1000, but I don't want to spend a whole lot more on modifications. I think the liter bike engine would be faster, but the v8 would be scary.

Thanks-

K-ville
01-29-2010, 11:11 PM
WTF? im not even sure what your asking... was that english?

Drifte
01-30-2010, 09:15 AM
It sounds like hes building a RWD car from scratch and looking for advice on suspension and drivetrain parts. Just buy a 1g Miata and strip it out. Swap the motor if you must but its a very lightweight car thats already street legal and assembled.

DustinsDuster
01-30-2010, 09:36 AM
for all-round performance, and price, i think youre gonna be hard pressed to beat a foxbody mustang. i dont know any of the dimensions though.

K-ville
01-30-2010, 10:00 AM
i can measure stuff on my fox for you but its not stock... and for a bike motor swap i get a miata they cant weigh much of anything

Clinical
01-30-2010, 10:41 AM
something like an MR2 would also work im sure, a fiero too perhaps

krustindumm
01-30-2010, 11:33 AM
Miata's aren't light enough. Bike engine target weight is 800lbs, V8 target weight would be around 1350lbs.

I 'could' use independent rear suspension from a Miata, but the whole thing weighs more than a solid axle, and takes a lot more time to calculate camber & toe change in bump and roll. The unsprung weight is lower, but I don't think the benefits will be worth the added complexity. Miata front suspension is a popular choice, but I was looking for a 'single-donor' solution, so I only need to part out one wreck to get the bits I need.

MR2/Fiero are very similar. They took the front of FWD economy cars and stuck it in the back. They aren't really designed to be sports cars, they're designed to be cheap. Also, they don't have a separate rear differential.

blackx-runner
01-30-2010, 12:05 PM
what exactly are you looking to do?

K-ville
01-30-2010, 12:30 PM
what exactly are you looking to do?

+1

K-ville
01-30-2010, 12:32 PM
Bike engine target weight is 800lbs, V8 target weight would be around 1350lbs

you can make a fox light but i doubt your gonna get it that light with a v8...... ive seen 1900 but there is nothing left haha

Scott
01-30-2010, 12:39 PM
yeah good luck getting a actual v-8 car to weigh 1350 with you in it! HAve you seen how much a v-8 engine and trans weigh? maybe if you built a go-kart chassis or something! I think buick makes a all aluminum v-8 thats really small and light though

krustindumm
01-30-2010, 01:12 PM
pretty much. I figure, I've got most of the tools, it's about time I use them.

AutoMods
01-30-2010, 01:17 PM
for a street car, fox body may be your best bang for the buck option but the fb rx7 is really light and the v8 swap in those are common. I've seen some sell really cheap already swapped . miata v8 swaps are out there too.

repost , Nelson 1hp per pound videos
http://www.youtube.com/watch?v=5t7DHsD0CDU
http://www.youtube.com/watch?v=2sI7tyBcMfQ

krustindumm
01-30-2010, 01:41 PM
All production cars have too many compromises.

http://grassrootsmotorsports.com/media/img/readerrides/SCCASolo071308_115_t352.JPG

It's going to be less work to build one of these.

blackx-runner
01-30-2010, 02:09 PM
why a bike engine, or a V8? what about everything else in between. Help keep the weight down and still capable of putting out some decent HP.

krustindumm
01-30-2010, 03:05 PM
Stock = reliable, and there aren't a lot of cheap RWD 4's or 6's that make good power. I-6's are too long.

I think I'm going with the bike engine and S10 spindles & axle. I found some specs and the axle width for the S10 looks good, and there were a lot of ratios available. Factory double a-arm makes things easy.

Bike engines have a sequential 6-spd...awesome.

NitrousMike
01-30-2010, 03:30 PM
for a road racing application I would go with a 4 cylinder or a 6, not only does it weigh less, so does the rotating weight, which makes a big affect on the handling with light weight vehicles.

Clinical
01-30-2010, 03:38 PM
I'd love to do a Fiero with a gtp motor and 6speed - gotta love the l67

NewSpeedSteed
01-30-2010, 04:23 PM
All production cars have too many compromises.

http://grassrootsmotorsports.com/media/img/readerrides/SCCASolo071308_115_t352.JPG

It's going to be less work to build one of these.

If your shooting for something like that why not a powertrain from a Cobalt SS or SRT-4?
I know that niether of those are really RWD motors but they offer forced induction from the factory making more power relativly easy and if I'm not mistaken the Ariel Atom (like a Caterham 7) uses the sc'd Cobalt SS engine and it is RWD. The Dodge's turbo 2.4 found its way into the AWD Caliber SRT-4. Heck even the Lotus elise uses a 2.0L Toyota Celica GT-S engine.
Maybe we can open the engine choices up a little? I know that an 8 would be ideal but for your target weght its going to be a bitch to get there.

Drifte
01-30-2010, 05:16 PM
Srt-4 can be had cheap if you like the engines. Like Ryan said the old rx-7 is light not sure how it compares to the miata. Build yourself a chromoly frame with a billet aluminum block. That's pretty light. Use a bike engine get the zx-14r, theirs some displacement.

krustindumm
01-30-2010, 05:33 PM
All production cars have too many compromises.

http://grassrootsmotorsports.com/media/img/readerrides/SCCASolo071308_115_t352.JPG

It's going to be less work to build one of these.

If your shooting for something like that why not a powertrain from a Cobalt SS or SRT-4?
I know that niether of those are really RWD motors but they offer forced induction from the factory making more power relativly easy and if I'm not mistaken the Ariel Atom (like a Caterham 7) uses the sc'd Cobalt SS engine and it is RWD. The Dodge's turbo 2.4 found its way into the AWD Caliber SRT-4. Heck even the Lotus elise uses a 2.0L Toyota Celica GT-S engine.
Maybe we can open the engine choices up a little? I know that an 8 would be ideal but for your target weght its going to be a bitch to get there.

Ariel Atom is mid-engine RWD, front-engine cars make for great conversions like that. What I'm wanting to build is a Lotus 7 replica, same as the Caterham, they're easy. Plans & cut lists easily available, and fit just about anything FR.

85XR7Project
01-30-2010, 05:51 PM
Why not try something like the Brunton Superstalker? RWD L67 FTW!

krustindumm
01-30-2010, 08:41 PM
lol, same thing, lotus 7 replica. Just looking for a good lightweight drivetrain. So far the bike engine gives me the best power:weight, and requires less in chassis reinforcement, because it weighs so little, and I can shorten it a few inches. It doesn't have reverse, but who needs that, lol.

Scott
01-30-2010, 08:46 PM
yeah of them super 7's with a carbon fiber body and a nice motorcycle engine and trans would be pretty sweet.. If you want a good deal on the drivetrain for that check out Legends class circle track cars, maybe get a wrecked one with a bent frame and have a good drivetrain in it! maybe even guages and shit too

AutoMods
01-30-2010, 10:01 PM
Do you want a street legal car or something your going to trailer to the track a couple times a month?

krustindumm
01-30-2010, 10:08 PM
yeah of them super 7's with a carbon fiber body and a nice motorcycle engine and trans would be pretty sweet.. If you want a good deal on the drivetrain for that check out Legends class circle track cars, maybe get a wrecked one with a bent frame and have a good drivetrain in it! maybe even guages and shit too

They're cool as hell. IDK if they can be made legal. I was planning on reusing the donor gauges. Can't get much lighter than OEM.

krustindumm
01-30-2010, 10:09 PM
Do you want a street legal car or something your going to trailer to the track a couple times a month?

I DD a bike, but I want a license plate. I don't need a comfy car, I don't even need a heater, just the legality to drive on the street.

69gt4speed
01-31-2010, 01:46 AM
Old volkswagon dune buggy setup be a cheap suggestion.

85XR7Project
01-31-2010, 06:57 AM
So wait... How much Hp is this bike engine going to have?

You don't want to make a Lotus Seven copy?

AutoMods
01-31-2010, 09:37 AM
I've ridden in a 400+ whp 1500lb hot rod once. It was cool and fast and a bit scary too. Of course there is a lot of downfalls to a street car that light too. I personally would rather go for more of a street car rather then a kit car and if you want more power to weight make up for it with the engine.

What was the power to weight ratio on the other cars you have owned or are driving now?

Drifte
01-31-2010, 01:26 PM
So you want this:
http://www.motorbase.com/uploads/candc/2009/07/14/fs_795572.jpg
And you want to drive it here (current time):
http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Photography/Images/POD/d/daytona-beach-625917-sw.jpg
And here:
http://www.cotswold-competitioncars.co.uk/cars/main/caterham%207%20race.jpg

Domestic Disturbance
02-01-2010, 01:38 PM
That picture of the beach is sweet. I wish I could go back to the 50s