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-   -   how much for an IT motor? (https://www.rx7club.com/race-car-tech-103/how-much-motor-441885/)

alberto_mg 07-09-05 11:06 PM

how much for an IT motor?
 
Hi. I'm doing research on racing costs and was wondering what the costs were for a competitive motor. The IT7, Spec7 and SCCA's IT classes seem interesting, but I'm wondering just how expensive it gets to compete. I got scared when I saw an ad for a BMW e30 ITS motor for $6k (think it was the 6 cylinder 325 not M3).

Thanks.

Gene 07-10-05 12:56 AM

There's limits to what you're allowed to do to the motor in IT. You might want to ask Joe, I think he works on some IT cars.

PaulyDee 07-10-05 05:10 AM

It will depend on who you buy it from. I have seen them as low as $2500 with used parts. The lowest I would go if I were buying it from someone is $3500 from ISC Racing. Speedsource charges something in the range of $4000-$5000.

I built a engine for my `91 ITS car and parts alone cost close to $3000 including getting the rotating assembly balanced by ISC Racing.

The concensus seems to be that the Speedsource engine will get you 7-10 HP more but I am not sure how they would do that legally.

christaylor 07-10-05 11:25 AM

You can also get a crate engine for ~$2k which is good enough. Put on a good carb and keep the whole assembly tuned properly and you shouldn't be down on power too much.

Hell, my dad's racecar has it's original engine with 90k miles on it, and it just put up 126RWHP on a proper (DynoDynamics) dyno. I think the equivalent number on a dynojet is like 5 or 600 horsepower! :rlaugh:

Plugs make more of a difference than you might think. You can throw in a new set of plugs, and if you're not careful of how they're situated in the housing, you can lose 5-6HP immediately. So, if somebody's running one of those fancy engines, and you set your plugs properly and use a crappy paper air filter, you've got the difference made up right there.

alberto_mg 07-10-05 01:10 PM

Can one run up front on a crate motor or a non-name-brand motor or do you really have to buy the name in order to win or run up front at the local/regional level?

I know the builder often has a lot to do with how much power and the reliability of the motor. What I'm not sure about yet is how well one can do w/o the name brand, how much the branded builders get for a motor...and if I can afford to run up front ;)

i like the idea of racing a rotary since the engines seem to last longer and seem to be cheaper to purchase/build a winning motor.

christaylor 07-10-05 04:13 PM

Here in Texas, all the Spec7 guys are running on homebuilt motors, crate engines, or factory engines. Texas Spec7 is a hybrid between East Coast Spec7 and IT7. Spec header, suspension, cage, tires. Exhaust must go over the axle and exit under the rear bumper. They allow IT engine prep rules (except all parts must remain 81-85). The guys that won the SCCA and SRX7 Series championships in 2004 were on Mazda crate motors. The leader in this years' points is on a built motor, but I'm not sure by who (I think Buddy Boswell).

In ITA, I'm not as sure of the engine builders (we have no IT7, so all the RX7's that aren't Spec are there). The car I work on, which has been bridesmaid two years in a row has a motor I think by Larry Oka (don't ask me how it's still running and making decent power -- I'm speachless). One of the others has a 10 year old Rotary Performance, but beyond those two I really don't know. I know none of them are running Speedsource or ISC -- they're not real popular around here (of course, we're not in the SE).

My personal opinion is that driver skill will make up for as much as 20 horsepower. Being able to carry speed through one corner and onto the next will make up that much of a difference on a point-and-squirt driver. It gets proven time and time again here in the SWDiv, and it's evident in the more competitive SE races.

I would guess in the NE you could do well with a crate motor. As I recall you guys have to run with the stock manifolds, so finding the one with the most flow and a good exhaust will do you a lot of good. You might poll some of those guys and see what the top-5 or top-10 are running. I would guess there would be a lot of homebuilds and factory engines, but that's just a WAG.

Dick Elliott 07-10-05 04:14 PM

Crate Engines
 
SPEED COST! HOW FAST DO YOU WANT TO GO? ( I think Henry Ford said that in 1903)

jgrewe 07-10-05 09:50 PM

In a class like IT where there is only so much you can do within the rules, knowing every little trick is how the 'name brand' builders get a few more HP. You can build your own engine and get pretty close to there HP with a rotory. After building 20 or 30 of these engines they find out what parts matter and which ones might work a little better. If you are spending a lot of money chances are the guy who built it spent time with a flow bench testing a bunch of stock manifolds to find the one that flows a bit more. Or he's found that with a little misalignment within the rules he can get the stock parts to flow/work better.
So you can put your own together for a $1000 and get 125 hp or pay $3500 and get 135hp. Most of the time its the little things you can do tuning that get you the cheapest HP.
Its also more fun to drive by a $3500 engine guy with your own, better tuned, $1000 engine. Make the most of what you can afford by handling the details better.

Speed Raycer 07-10-05 10:31 PM

My advice... take that chunk of change that you want to spend on a fresh new "competitive" motor, and spend 1/4 of it on a low mileage motor and the rest of it on seat time and tires. Once you've got some seat time and you're lap times have leveled out, then start looking at how to spend money to go faster.

One of the local IT7 guys holds the class track record at Gateway Int. High 1:13s or low 1:14's. Motor is so stock it's not even funny. Original motor, never been out of the car. Orig. tranny. Brake ducts? Nope. Air Dam? Nope. Panasports? Nope... stock + wheels w/hoosiers. Wicked suspension? Nope. Illuminas/camber plates/Eibachs... just like everyone else. Ok... he does have a Yaw carb... :D

Before you laugh at the high 13's/low 14's, he's been known to battle ITB driver Chris Albin for the overall and those times are SOLIDLY at the front of the ITA pack.

KNONFS 07-14-05 10:50 AM


Originally Posted by alberto_mg
Hi. I'm doing research on racing costs and was wondering what the costs were for a competitive motor. The IT7, Spec7 and SCCA's IT classes seem interesting, but I'm wondering just how expensive it gets to compete. I got scared when I saw an ad for a BMW e30 ITS motor for $6k (think it was the 6 cylinder 325 not M3).

Thanks.

A buddy of mine races in ITS, engine miust be stock, stock manifolds, header with your choice of dual (individual) or single exhaust. Suspension was a free for all in terms of brand. He was among the rotary leaders lap time wise, however the BMW were too fast for the FC. His engine was a crate engine from Malloy Mazda

He was selling his car a couple of months ago, I can hook you up, if you are interested.

C. Ludwig 07-14-05 12:17 PM

There are blueprinting tricks that when stacked up can add up to a few horsepower. Side seal clearance is just one point of interest. Keep it tight for better compression. I've measured factory fit side seals with low mileage at around .008". Way too sloppy. In that case you're losing compression to blow-by and power suffers. Another point is longevity mods. Our engines will see 8500rpm shift points and 9000rpm on occasion. Are factory balance jobs, bearing clearance, rotor clearance, etc up to the job? These are the things you're buying when you drop that chunk of change for a Speedsource engine and the things you wonder about in the back of your mind when you're spinning that crate motor or junkyard motor well past it's intended operating range. Keep the revs down and the crate motor will last. Run it where the power is and the high dollar Speedsource engine will make more power and last just as long.

As far as the extra 5hp...is it worth it? When you're running mid pack no. There's other things that are holding you up besides HP and that last 5hp isn't going to put much of a dent in your laps times. But when you're at the pointed end of the field and everything else is sorted then that 5hp can and will show up.

alberto_mg 07-19-05 08:03 AM

hey guys. thanks for all your input. i'm on my honeymoon right now, but will be reading this more in depth when i get back.

meadespeed 07-25-05 08:20 AM

Get a hold of Rob at Pineapple. Seriously. Then if you cant afford it or cant stand to wait I can have Mike J. (Dan Atkins protege) build you one that is equally up to par.

alberto_mg 07-31-05 03:33 AM

I'm at the airport now waiting to come back to NY from my honeymoon and reading the thread. Thanks very much guys. It does indeed sound like one could be competitive w/o spending the big bucks on a brand motor. Just what I wanted to hear :)

My point of reference for this is from my karting experience. I used to run Sportsman with a Yamaha kt100cc motor. If you didn't have a motor built by one of the big guys, you weren't running up front. There was also a fair degree of difference in the way motors would perform between builders. I was running an Emmick motor and chassis running against a Woltjer and the Woltjer seemed to have more torque while my Emmick seemed to have more top end. Made for a very annoying run on the front straight where the Woltjer motor would be able to nose ahead at the beginning of the straight while I would start making the space back more toward the end of the straight. Mind you this is fighting wheel to wheel in various races in multiple seasons using the same gearing and overall weight.

We'll see how things work out over the next year. Racing karts is a lot of fun, but I'm almost ready for something new.

banzaitoyota 07-31-05 12:53 PM


Originally Posted by meadespeed
Get a hold of Rob at Pineapple. Seriously. Then if you cant afford it or cant stand to wait I can have Mike J. (Dan Atkins protege) build you one that is equally up to par.


IF ROB remembers to install the oil squirters in the E-shaft!


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