I am about to purchase a new car for auto-x, and rather than re-building my B series motor and probably classing myself above my limits, I was considering rebuilding the (stock) motor to a 'prepped' motor. I have heard this term several times over the years, but now I can't find anything on it. I have spent a few hours searching around the internet and cant come up with anything specific.

I am looking at a auto-x/hpde set-up.

I would assume a balance, blueprint, maybe rebuild everything a little 'loose' ...just wondering what would go into such a motor...and lastly the question of how much something like this would cost?

 

It depends what level of "prep" you're talking about. A Nationally-winning Spec Miata motor, for example, would most likely be something like $8-10K (I'm really ballparking that, I haven't priced it myself), and would involve very precise machine work (bore, headwork that's legal, etc.), matched piston weights, crank work, etc. The last issue of GRM had a real brief overview of what's involved with putting together a competitive motor, that might give you an idea. Also search for "Sunbelt Engines".

It comes down to "how competitive do you want to be?" And then "the more competitive you want to be, the more money you need to spend (if your hands and feet aren't blessed by the gods of speed)." The type of prep I listed above would yield like 3-5hp more than the next built motor. If you look at similar levels of racing, ITA or H4 for example, there are motors being built in a similar fashion (not sure about the piston weight thing) that clearly have more oomph than the next guy who just threw a junkyard motor in.

It doesn't sound like you're trying to win your class at Solo Nationals. And the HPDE championship doesn't matter In my opinion, just give yourself a fresh, clean rebuild on whatever motor, spend the other thousands of dollars on tires and entry fees.

 

+1

I am "prepping" an engine right now for H2 Honda Challenge, and I am spending more than triple the cost on petty crap to gain fractions of HP. But you know what...if I have 3 more HP than the guy next to me on the straight away in H2, it's worth it. And if I intended on only local stuff, I wouldn't try as hard either. But I have already put around $20k into a car that blue books for $600 on other upgrades.

Just put your money into a fresh, reliable motor and make yourself competitive for one class with suspension, interior items, engine bolt-ons, and experience. That should eat up your budget right there.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GI8U2racing &raquo;</TD></TR><TR><TD CLASS="quote">+1

I am "prepping" an engine right now for H2 Honda Challenge, and I am spending more than triple the cost on petty crap to gain fractions of HP. But you know what...if I have 3 more HP than the guy next to me on the straight away in H2, it's worth it. And if I intended on only local stuff, I wouldn't try as hard either. But I have already put around $20k into a car that blue books for $600 on other upgrades.

Just put your money into a fresh, reliable motor and make yourself competitive for one class with suspension, interior items, engine bolt-ons, and experience. That should eat up your budget right there.</TD></TR></TABLE>

Well said

 

interesting. I have looked at a few cars with high mileage and thought ...if im going to rebuild this, I may as well do this right.

Thanks for the input. Any more would also be appreciated.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by junkyard racer &raquo;</TD></TR><TR><TD CLASS="quote">interesting. I have looked at a few cars with high mileage and thought ...if im going to rebuild this, I may as well do this right.

Thanks for the input. Any more would also be appreciated.
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I bought my car with the B18C5 in it, and it was a train wreck. It had Koni Yellows and decent seats, but at times I would have rather just started fresh. Now I love the thing, understand it, I made it what it is today, and wouldn't want anything else.

If you buy a car, make sure it will be easy to build, and you won't have to keep taking steps backwards to keep it running. Buy a $1000-2500 car and an engine swap in your budget to be competitive for a class you want to run in. Then make the car handle good, run it as you build it, experience the differences, learn along the way, you will gain lots of knowledge, independence, have a great time, and will probably win some events too.

CRX HF's, EG MPFI Civics, those are cheap solid starting platforms

 

I have been auto-x'n for 2 years, and coming home with 2 motors, suspension, LSD tranny, etc. to build my next car...so 90% of the 'building' is done. All I need to do is get my motor rebuilt and get a car to put it all in. I was considering getting rid of my B series stuff and sticking to a more 'prepped' D series...which is why I asked the question.

 

I would not build a "loose" engine if I had to drive the car to and from events. Also how competitive do you plan on being at autocross and what class are you building for. I say this as there is no need to do a crazy build for a DE car. I'm DE'ing a 96 Integra RS with 140K+ engine, compression is good and the diff and fd I just installed the car should be even better. We AutoX a 88 CRX Si in CSP the bottom end is all stock but we have changed the IN, TB and had the head port matched. It will be tuned soon. Locally it is fast Nationally we would be a back marker. But its just for fun!!!!

The GRM article is a great place to read up on a "RACE" engine build but not for a car that will see DD use AutoX and DE use its pissing money out the window.


Modified by vbspec at 4:19 PM 4/15/2008


Modified by vbspec at 4:22 PM 4/15/2008

 

A true race build in my mind is a motor that lasts a weekend of racing and then starts to let go. you've tuned for maximum power and acceptable reliability and then you do it all over again b/c you can and you are forced to b/c of stiff competition.

Basic Club racing and AutoX = reliable motor, good reliability, med cost and good power that lasts a couple years even if you are at the top of your class. By the 2 year mark you might have to change your setup significantly anyways to keep up with the new hottness.

Basic prep I would be doing is obviously ballancing the setup, polish the crank, shot peen the rods, coat rods and pistons, build head if applicable with true and tried mods and parts.

 

better study the rule book and see what can be done in the class that you are competing. You will be surprised on how little you can do to your engine, especially for autox.