Largest cams in a hybrid?

[Jpizzzle]

Well, i was waiting for Brian Crower stage 3 WRX cams, ever since January when they said they would be out in february. it is now august and i just contacted them and they say it will be atleast another 5 weeks...sorry BC, you just lost a customer, 8 months to make some cams? come on! they were already paid for in a large purchase from a vendor who i dont blame, so they were cheap and for the size of these i thought they would be a good deal. i am not on a strict schedule but at the same time i want to get this done as these have been the only thing i have been waiting for in the last 8 months. the short block has been built for months now but i cant move further without cams. So now my question...

I was going to run these 280 degree intake and exhaust cams but did some talking with a friend who builds motors and he has me wondering if these would be too large? the 2.5l engine is fully built with EJ205 heads. i have stock modded 850 cc injectors with a walboro 255. Would this size cam be too large for me? i just figured go big or go home when i ordered them but now im questioning myself as bigger isnt always better. How would this idle or would it idle at all? does anyone have a similar set up with cams this size? what seems to be the largest cam that is road worthy? i like lumpy but i like reliable more. i like the idea of the possibility of more power with a larger cam but if the car doesnt run, there is no power! looking for any help, tips, pointers or anything i can get from all of you.

Thanks
Jon

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[checque]

I'm no expert on heads so hopefully someone else will chime in with a good explanation for you, but here's what I think I can safely offer:
Heads CAN flow too much, although it's unlikely your builder or porter would allow you to have that kind of setup or do that kind of work to them.
If this is going to be a daily driver, I really don't think you, or anybody else sitting at a stoplight next to you, is going to like it. Some tuners/builders can get large cams to idle really well, but not many. My brother has 282 cams in his DSM and is sounds like **** idling at 1200rpms (but he has lots of other problems that don't help that out any, it's a DSM). I'm guessing yours might idle around 1k?
What turbo do you plan on running with cams that large? You can stuff all the biggest things you want under the hood but you're not going to get great power unless everything is matched up properly. 280 cams would probably require a 35R at a minimum, more likely something in the 40R range though. Check some posts and see what setups are using 280 cams and definitely talk to some more knowledgable people, i.e. builders and tuners who've done setups like that.
You'll probably need an aftermarket fuel pump or dual 255s with whatever you're planning on anyway.
Hope that helps and I'm not too far off-base.

[ilivas]

I'm running 272 cams in my built hybrid 2.5. It has dual walbros, 1150 cc injectors, and a rotated T04R turbo. It's not completely done yet, but I'll post results when completed. It will be sson.

[saintluciascooby]

Take a look at/speak to Rigoli's about there race cams
http://www.tonyrigoliperformance.com...gineparts.html
.
I like then more the the 272 juns I had.
Jon

[MY99 2.5GT]

Depends on where you want to make power as well. Most 272 and above cams let the engine breath too much to make good power/torque down low. Man will it be a killer up in the 6-8k rpm range with a large turbo. It will hit like a freight train rather then a smooth ramp-up.

[Jpizzzle]

Thanks a lot everyone, i need to check out those links, any other info would be great! im planning on running my deadbolt SZ55 turbo. i have methanol injection if that helps any and a walboro 255. any other info needed just ask.

[dibblejr]

I recently lost my engine so am having another one built. This time for autoX, rally and rallyX in mind. I am going with Kelford 264/272's this time for the low end power needed to be competative in thos events. I am keeping my VF22 and 840cc's until the turbo gives up, then I will probably go with a big 18g or 20g.
As mentioned above cam selection would depend on where you want the power.
I have not taken the blown engine apart yet to see what gave up. I am thinking at least 2 conrods when my tuner sugguest just stuck valves.
I have been awaiting my Kelford cams and heads for over 2 months, now they are on the way here so pretty soon I will find out what went wrong with the old build.

[Jpizzzle]

OK, so new question; Where would my power band lie (just a round about guess) using 280/280?

[dibblejr]

I am guessing 5500 + for those. Thet are way to big for a DD IMHO.

Jay-R

[Jpizzzle]

wow, that would be fun...i would guess that i would probably want to bump up my rev limiter...

[keaniegenie]

Look up the dynochart on www.elementtuning.com of a hybrid with an FP Green

It usesd 264 intake and 272 exhaust cams and still spooled nicely.

[dibblejr]

I dont think the cams you have posted are in the question being addressed. He asked for 280/280, your help, none at all.

Jay-R

Originally Posted by keaniegenie

Look up the dynochart on www.elementtuning.com of a hybrid with an FP Green

It usesd 264 intake and 272 exhaust cams and still spooled nicely.

[Josey Wales]

280s will give you nasty cold-start issues and possible problems with idle. From what I have seen they don't function very well with a reflash aslo.

Your car will be a real PITA in daily commuter-style traffic.

It's a bit much for a daily driver, but I would do it .

[Homemade WRX]

personally my 35r set up is on 274/278's and the 282's aren't being touched until the 42R is in.

[M3GTR]

274/276 with a 40r, twin walbros and 1600cc injectors, idles really well at about 1200rpm even when cold.

[dibblejr]

Anything will idle @ 1200 rpm's. Still not great for a DD car, race only apps FTW.

Jay-R

[Jpizzzle]

Are these WAY TOO BIG for 845 injectors, deadbolt superzilla 55, and single walboro 255?

DrinkAV8, i like your style!

[sku81]

for a street car 280's are alittle over kill,idle at 1100-1200 rpm
Cold starts are fine(motec M800 handles them fine)
As for power range,I couldn't tell u atm.

Kris

[Homemade WRX]

for street I would go 272 and 274/278 at the biggest...

[Granny's Garage]

So basically what i get out of this is that these are streetable, not preferably the best, they will perform well, its just that idle will be a little high unless it can be tuned around. The only reason i ask is because i have already bought them, just waiting for them to arrive and if they are way out of control and just plain stupid to put in the i was going to sell them and get a different set. It would just be fun to see what they can do...

[Homemade WRX]

yes, you can street drive a 4202R too...just not the most liked street set up

[Jpizzzle]

Ok, so what is not "streetable" about these? just the possible high idle or is there driveability issues?

Thanks all for your input

[Homemade WRX]

I would imagine just the high idle to be the only turn off...that and guzzling gas

[Jpizzzle]

Thats true, I cant a imagine what the MPG will be after these...anyone have an idea? or what do people with 272's or bigger get on average?

[flwrx]

Originally Posted by Jpizzzle

Thanks a lot everyone, i need to check out those links, any other info would be great! im planning on running my deadbolt SZ55 turbo. i have methanol injection if that helps any and a walboro 255. any other info needed just ask.

I will be running Kelford non-avcs 272's with 2.5 block, built sti heads, and SZ55 also. Prob will be a while til its done tho