Best n/a 2.5L build possible?

[nando]

M20 stroker (2.8-3.0L) with a Racing Dynamics 24v head < all.

or you could get an m52b28?

[Rodoni]

But RD 24v head beats all at the rarity level ;)

Edit: I tried to email RD to see if they would reproduce that head. I got side tracked but I am still going to try. They might go for it if we get like a signed petition with money up front. I just thought it would be cool. Doesnt hurt to try, right?

[FredK]

How so?

Dollar for dollar, if you spent the same money developing a K24/K20 hybrid engine or an S14, you could end up at the same point, most likely. The number that gets bandied about is roughly 300 whp+ on a heavily worked 2.5L S14. This will bankrupt you, though.

[884door]

Dollar for dollar, if you spent the same money developing a K24/K20 hybrid engine or an S14, you could end up at the same point, most likely. The number that gets bandied about is roughly 300 whp+ on a heavily worked 2.5L S14. This will bankrupt you, though.

I personally think the Honda motor would come out cheaper and parts are much easier/quicker to get ahold of.

If you started with an f22c those are like 247hp stock and can be had for around $3-4k. Obviously fully building a motor is expensive no matter what but the F series motor could make 300hp for a lot less money IMO.

[Philo]

About $15k gets you a brand new Race S14 from MetricMechanic. @285HP

[lennon]

How so?

because this is an e30 site;)

s14 vs. f20

http://www.e30m3project.com/e30m3performance/tech_articles/engine-tech/flow-1/index.htm

[nando]

so much misinformation....

my rx8 burns less oil than most e30s. about a quart every 3000 miles. its not even an issue. i never add more oil. i just change the oil, because its time anyway and im back to full.

and a rebuild every 20k miles? lol. i know a few people that have 15-20 2 day track events, and dozens of autoxs with over 100k on their motor. quite a lot of rx8s with 60k-80k miles with dozens of track events. its a newer car, so not a lot of really high mileage rx8s. highest i've seen so far was 186k. engine was still strong.

im at 60k, motor is still strong. maybe 3 dozen drag runs. a dozen autocross runs. and 2 track events. one of which was a 2 day event.

biggest killer of rotaries is driving like a granny. hitting the daily redline clears out excess carbon and prevents it from building up. so all those people who "never abuse the car and always shift under 3k rpm" are killing their engines. i really dont think hitting the redline once a day is such a deal killer.

you can argue until you're blue in the face, I've had lots of rotary friends. They're pretty good at pulling engines. It's like doing a timing belt change on an M20.

also, a quart in 3k is pretty high imo. Mine probably leaks half a quart, but it does'nt burn it. :p

[TwoJ's]

s14 vs. f20
http://www.e30m3project.com/e30m3per...ow-1/index.htm

Cool. I'd never seen that.

[E-Thirty]

And it's such a shame where Honda is going now...

[rThor432]

And it's such a shame where Honda is going now...

What do you mean by that? I haven't followed Honda's current offerings/technology.

[nmlss2006]

The works 2.5 S14s got 330-340 flywheel HP in 1990/91. I would be exceedingly skeptical of any claim even approaching those numbers, never mind exceeding them. It is true that you wouldn't have regulations to contend with, it is however also true that the 330HP engines were not exactly durable.

[livetheride]

you can argue until you're blue in the face, I've had lots of rotary friends. They're pretty good at pulling engines. It's like doing a timing belt change on an M20.

also, a quart in 3k is pretty high imo. Mine probably leaks half a quart, but it does'nt burn it. :p

1 quart/ 3k is nothing. most companies spec 1 litre or more per 1k.. For an engine that self lubricates through mixing oil with gas, i'd say 1 quart is nothing.

And any day of the week, you can build a huge horsepower rotary for pretty cheap.

[Kershaw]

^ yeah. as i said, oil consumption is not a big deal to me. by the time it goes a quart low its time to change the oil. so i never have to add any extra.

huge horsepower is easy with the rx7 motor. the 13b-rew makes gobs of horsepower very easily, especially when peripheral ported.

the rx8's renesis.. ehh.. i know of 1 500whp renesis. a handful of 400whp renesis motors. 350whp and below is pretty easy to achieve with less than 10 grand. if you want crazy amounts of horsepower, you do a 3 rotor swap. then 600-1200whp is attainable. (with shit tons of money.)

horsepower aside, the rx7 is not very reliable. the rx8 is pretty hard to squeeze more horsepower out of naturally aspirated, and doesnt make crazy amounts of horsepower with force induction. the rx8 is, however, much more reliable than the rx7. its still not a honda civic. its also not an m20.

everyone is impressed with a 225k mile rotary. people go meh to a 225k mile m20. that says something, even with all the misinformation about rotaries.

[nando]

they're probably impressed that a rotary made it to 225k :p

[SA E30]

The works 2.5 S14s got 330-340 flywheel HP in 1990/91. I would be exceedingly skeptical of any claim even approaching those numbers, never mind exceeding them. It is true that you wouldn't have regulations to contend with, it is however also true that the 330HP engines were not exactly durable.

Afaik, by the end of 1991 they were closer to the range of 360hp.