New Spider Build: Challenge a Lotus Exige

[jasonboes]

Hi Everyone,

I am looking to overhaul my 81 Pininfarina. My goal is to out perform a Lotus Exige. If you look at the specs of the car I really believe it can be done. I know it is going to cost some money and it will take a lot of fabrication to do it. I like to take my projects and put them somewhere on the web and I think this is the best place to do it.

The story is that I had a co-worker that bought a Lotus. It is the 218 hp version and it is a pretty impressive machine. I want to make my Fiat out perform it. I own a shop and I can build the motor and do all the cylinder head work myself. I also know how to build a megasquirt system. So I feel that I am more than capable of doing this. I kindly request that anyone that wants to say that you can't do this please refrain from posting to this thread. I have a body shop and a performance build area.

Here are some of the ideas that I would like to discuss. 1. Power Adders 2. Nitrous 3. Running E85 fuel 4. Any combination of these. Fuel choice could impact a lot on the performance end. I am thinking that running E85 with nitrous might get me to the next level. Given that it has a higher octane and you can run higher compression. I am trying to get as close to 300 hp as possible.

Next is dropping weight off the car. According to what I have read I can get 4-500 pounds lighter than his car. So that should help with handling and performance when racing him. I know I am going to go with bigger brakes in order to be able to brake later in the turns. I am hoping to get something to take the bolt pattern to a Miata type so I have a wider wheel choice in the 16 to 18 inch range. If I have to I can tub and flare a little.

For the drive train, I was talking to a guy at Vick's and I should be able to get a hold of a stouter trans for the car. Custom drive shaft will be in order, and I am going to try and get the Mazda Miata IRS in the back of the Fiat. I am pretty sure I can do it. It is just building the support beams in the right spot to mount the suspension to the car.

I have owned the Fiat for about 8 years now. I figure it is time to do something with it and I think it will make a great track car. The Exige seems like a good performance goal to meet and I know it is doable. So how do you guys think is the best way to go here?

Jason Boes
SillyFast Customs

[fiat218]

Naw!, you can't do that damn it

[rja]

i, for one, would love to see you do this. and follow this build. with a lotta pics. don't have much to suggest; maybe take a look at rx-7/8 irs also. they can take a lickin' and keep on...well you know the rest. good luck.

[TX82FIAT]

Jason, I read your thread a couple times. Inrteresting concept. You address fuel type, transmission, differential, bigger brakes, more support for frame and shedding weight. These are all steps in the right direction. I'd love to hear more about the engine itself.

Head modifications, Size of intake and exhaust valves, Cams, Block modifications, Domed HC pistons, intake modifications.... Spiring, valve guides, crank shaft, fly wheel....

If you hit 300 HP it will be a fire breathing dragon and I am in the camp that absolutley would love to see that. Assume you do hit 300 HP with a nitrous add. How durable will the engine be.

I think if i were going to spend the time and money this project will require I'd also have to consider alternative engines. with that said... I'd love to see a Fiat engine modified to beat an Exige.

[jasonboes]

I have talked to a few people and the crank and rods should handle the power. The question will really be if the block can handle it. I know large valves are in the picture, but I am not sure if I will shave the head or go with the 1800 head. I thin shaving the head will allow me to dial in compression better. So it is off to do the math and see where I can go with this. Also I am a big believer in staying with the fiat motor. Maybe I can't get there but it won't be for the lack of effort!

Jason

[jasonboes]

Second Generation (NB)

Production 1998–2005
Body style 2-door convertible
Platform Mazda NB
Engine 1.6 L (98 cu in) B6-ZE I4 (Europe/Japan)
1.8 L (110 cu in) BP-5A I4 (Japan)
1.8 L (110 cu in) BP-4W I4
1.8 L (110 cu in) BP-Z3 I4
1.8 L (110 cu in) turbocharged BPT I4 (Mazdaspeed)
Transmission 5-speed manual
4-speed automatic
6-speed manual
Wheelbase 89.2 in (2,270 mm)
Length 155.3 in (3,940 mm)
2001-02 & Mazdaspeed: 155.7 in (3,950 mm)
Width 1999-2002: 66.0 in (1,680 mm)
2003-05: 66.1 in (1,680 mm)
Height 1999-2002: 48.4 in (1,230 mm)
2003-05: 48.3 in (1,230 mm)
Mazdaspeed: 48.0 in (1,220 mm)
Curb weight 1,065 kg (2,350 lb)

____________________________________________________________________________________

Exige S

Manufacturer Lotus
Production 2006–2011
Assembly Hethel, Norfolk, England
Predecessor Lotus Elise, Lotus Exige
Class Sports car
Body style 2-door coupé
Layout MR layout
Engine 1.8L Toyota supercharged I4
Transmission 6-speed manual
Wheelbase 90.6 in (2,301 mm)
Length 2006–07: 149.5 in (3,797 mm)
2008–2011: 149.0 in (3,785 mm)
Width 2006–07: 68.0 in (1,727 mm)
2008–2011: 67.7 in (1,720 mm)
Height 2006–07: 45.8 in (1,163 mm)
2008–2011: 45.0 in (1,143 mm)
Kerb weight 2,057 lb (933 kg)
Related Lotus Elise, Lotus Exige

_____________________________________________________________________________

Using a 1 inch wheel spacer n each side will match the width of the Exige using a Miata IRS. I will have to look into the oter cars. Thanks for that suggestion!

[Redline]

I would love to see a 1500 lb, 300 hp Fiat with a chassis that isn't a noodle supporting an fully-adjustable, rose-jointed IRS and front wishbones. Throw in semi-slicks, Öhlins with remote reservoirs and some useful downforce and get the whole C of G about 4" lower and I think you're in with a shout against the Exige. Oh, maybe ditch the steering box for a decent quick rack.

Since you asked what you need...

What may be more fun would be to replicate the Grp 4 rally car of the 70s. More than a handful and beautiful to see / hear.

[mgbgtn]

What about supercharging or turbo charging. These are quite common hop up mods for 1600 to 2000 cc Miatas and are well developed for these motors.

[ga.spyder]

Out perform the Lotus? Drag race or lap times? I think lightening the car and building a snortin' motor is do-able,and the straight line should be better than the Exige.Beat it on a road course...you are going to have to do a lot of suspension mods and a complete make over of the braking system.The Exige is an extremely capable track car.You will need to replace all the 80's technology with more modern systems.Interesting project though,and I will follow it with great interest!

[Kevin1]

Use the tried and true Shelby Formula...
Strip it down to the tub, replace the front crossmember with a Ford K-member, go with mustang rack, hubs, brake and suspension. The k-member opens up a lot of options for motors that would get your 300hp goal easily. T-5 Tranny, Mazda IRS, and somewhere to squeeze in a fuel cell.

Oh, and lots of pictures, no matter how you go about it!

[jasonboes]

Here is the start of the suspension. I will have the car in the shop next week, so stay tuned for more pictures!



Hopefully the picture will load.

Jason

[divace73]

I would like this to come to fruition, however you will spend a lot more than the cost of an Exige to get it to the same spec.
If Cost isn't a factor and it is the "cause I can" factor, then I'd seriusly consider the Fiat 5cyl 20Valve turbo motor and that fully blown keeping the heart in the family.
The 131 box is reported to handle some power but not sure of it's maximum, something would have to be done about the diff I imagine for massive power.
And as mention previously some serious suspention mods to have the spider handle anything like the lotus.
Have most of the body replaced with carbon fiber but ensuring on the outside it was painted like a 'normal' fiat spider with no clue carbon fiber has been used.

I've driven the cup250 Exige the one that has the super charger and it is seroiusly quick and sticks to the road like glue. It was by far the fastest thing I'd ever driven on the road.

Lotus have always been good at making light cars which we all know the key is power to weight, not power alone.

[SLOSpider]

Here is the start of the suspension. I will have the car in the shop next week, so stay tuned for more pictures!



Hopefully the picture will load.

Jason

Not to say anything bad but thats a good start for a street car. You should at minimum have coil overs as a few other have done here with less aspirations as you have. As stated above a Mustang 2 front end would be nice but you can still do coil overs and rack unit with out it. The plus side is front would be done and have numerous choices for suspension, brakes and wheels. Rear would be a shorten 9" rear end with multi link suspension. Rear independent would be nice plus its only money.

[jasonboes]

With the Exige being about 65K here in the States my girlfriend would castrate me if I spent that on this spider! LOL!

I figure the 131 Trans might work but I am going to have to compete with a 6 speed trans there. So I am looking at other options. You can make your own bell housing that can adapt any trans to any motor. You might even get a 1 off made by Lakewood. The other trick up my sleeve is that I am next door to a metal fabrication place with a very capable laser cutter. And being friendly with them really brings down the cost. So it might be a situation where it is completely fabricated.

Also moving anything I can to the back will help with weight distribution. Have you seen how light our cars are? Looking at the the specifications of everything I think it can be done.

I get what you are saying about the new motor. That would be expensive. I can prep the whole block. Then buy new bearings, pistons, rings, and upgrade the oiling, heads, cam, and cam wheels and be pretty good with flow. Mind you I have the tools to do all the rework myself. So Engine wise we are talking 2 or 3k. Suspension out of a Miata in the rear I have already sourced for $950. Front work should be in the same ball park. So when I total it all up I would be surprised to be into it at more than $10K.

This build will happen in stages. The brakes and suspension are first. I am going to gut the car for the track and get a baseline on how it runs now. Then I am going to put the suspension on and test the car again. I am going to fully document everything. If I have to have a special bracket made I will do it in CAD so that I can reproduce them and have them run off in quantity. I will probably have to flare the fenders. If I do it will be in fiberglass or carbon fiber.

Then after I am happy with the handling I will just add nitrous to the mix and see how well it is set up. Then over the winter I will start the engine and drive train modifications. I have thought this out for over a year now. I have a reasonable belief it can be done. Some of the things that have changed in the last couple years are the Megasquirt option and that E85 fuel is more available. I believe that these advances can really take our cars a little further.

So as I asked before, lets not say it cannot be done. Lets put our heads together and try stuff. If I fail to reach the goal then "oh Well". At least I failed trying. But I bet I have one heck of a car either way!

[jasonboes]

I bought the suspension 7 years ago and have not done anything with it. So I figured I would start there. I guess I should say that the only options to work with here are that it will have IRS. The suspension should be modified where it can be pulled from one parts car. Megasquirt will do the engine management. And the options on the motor build are up in the air depending on the fuel being used. I know I am going to have a power adder and I already have the nitrous setup. This will take a while. I am documenting it here. Please leave sarcasm and negativity at the door!

About me: I am not a kid. I am 37 years old. I have done a few things in my time. I spent 10 years in the Marines, and another 10 working in the biotech arena. Cars have been my love for a long time. I have done things with imports, euros, american, you name it. Here is my current stable:
2000 BMW 540i/6 w/M Sport
1975 Chevy Monza: Pro Street drag setup
1994 Ford Bronco (FSB 4x4)
1969 Ford E100: Mess with the Straight 6

In the past I have had Fieros, Miatas, Triumphs, Mustangs, and lots of others. So now I am planning to do some things that are unique and I trying to make a name with my shop. This is the first one. So I am going to see where it goes.