ThackerSS

Anyone know around the specs of the largest cam I could throw on some AFR 205's?

I am looking to go with an all out cam package.. hoping to make good numbers but I was wondering what the largest cam for the AFR 205's would be? I was hoping for something much larger then a 224....

Keeping stock "internals" as pistons and such.. just want a real nice head and cam package.. if I can't go with something nice and large I am just going to go all out cam only on the stock heads...

jrp

iTrader: (16)

hmm, guess you missed J-Rods AFR post , if you want max effort wait for the 225's.

BlueSix

*cough* 225's *cough*

Ben R

A big cam won't benefit you very much if you're using a stock bottom end. A big cam on these 346ci motors means turning a lot of RPM (7000+) and the stock shortblock simply isn't capable of that kind of abuse. Now, if you want to build a stock CI motor that is capable of turning a lot of RPM, a big cam might be warranted.

Picking an effective heads/cam package is a lot like give and take. The nicer the cylinder heads, the small the matching camshaft will be. Your motor only needs so much air per cylinder, which in turn means that for any given RPM and corresponding cylinder head flow through an intake manifold, one and only one camshaft will provide optimum power. Optimum power depends on your application, of course.

FASTONE

You meant the 225"s right???

FASTONE

damn, three post at once!!!!!

jrp

iTrader: (16)

ya thats what i meant, typing and checking out this chick patty's *** at work dont go hand in hand

Ben R

Baby got back! LOL.

BlueSix

They'll go hand in hand when your hand is on her ***......

that really made no sense...

J-Rod

How much RPM do you want to turn?

Look at the CFM discussion thread where we talk about how much duration you need for X RPM vs the head flow.

Synopsis: Bigger isn't always better... Smarter is...

Grant B

I emailed Tony @ AFR with my very detailed requirements for a H/C package, and he responded with a detailed solution You might want to do the same. I didn't get a very detailed response (if I got one at all) from the other vendors I emailed...

Remember you need to consider the car's gearing, that and the redline will determine the RPM range where need to have the most power.

The thread J-Rod is talking about is here:
https://ls1tech.com/forums/showthrea...&highlight=CFM

I notice he mentions that less duration would be needed with smaller runners. Maybe thats why Tony recommended a 220/224 110 LSA cam for me? I basically need power from 4000-6400. A low (or no) maintenance street and road course application.

PS: Does excess lift hurt velocity?

PREDATOR-Z

Hmmm that could be a thread in itself??

-=Merlin=-

Just as J-Rod has posted.............the question is not which is the biggest, whats the most efficient cam out there.

DAPSUPRSLO

iTrader: (14)

All you guys and your theories, I am getting a headache. I would say the trend has been bigger cams produce better times in the ls1 so far. You can't really over cam this motor without cutting the pistons it seems based on the 15 degree valve angle. I believe thunder racings philosophy was just put the biggest cam you can fit in there without having to flycutt the pistons and see what happens. What happened, realy fast quarter times and really high dyno numbers. I would try a T-Rexed sized cam with the 225s and see what happens.

It is all in the combination though. You must have at least 4.11 gears to run this setup effectively at the track and all supporting boltons. Even if the power band is still to high for the stock shortblock it is still smashing the smaller cams in the 4500 to 6500 range where all stock shortblocks are capable of spinning and even higher and this is where we race, not 1500 to 3500 rpm. Just my honest opinion.

-=Merlin=-

Theories huh?

Then why is it a friend of mine made 410rwhp/390ftlbs with a 222/226 cam only, spec'd based on VE's, when there are others making the same with those "bigger is better" cams AND heads .

Edit: BTW the IAT's were 91 deg, I know because I was sitting in the car monitering the vitals during the dyno runs......

distortion_69

iTrader: (20)

He will be running FMS ported AFRs... not exactly equivalent to a 205cc AFR head. The answer is.. depends on how much the heads are milled, and the exact specs of the cam. I wouldn't worry about it, if Allan couldn't match up combos, he wouldn't have some of the highest dynoing cars on the board.

Peace,
Josh

DAPSUPRSLO

iTrader: (14)

Big deal, what is that through a ten bolt? What kind of numbers are generated by the T-Rex, better then those. Those numbers are good but not incredible. I made 405 rwhp and 406 rwtq with a much smaller cam then I have now, 224/224 110lsa 106icl 568 lift compared to my 230/236 107lsa 107icl 574/572 cam with only made 392rwhp and 377 rwtq through a twelve bolt. Guess what, with the exact same setup with the only difference being the cam swap I picked up two mph and a tenth with smaller dyno numbers (all runs were on nittos so the e.t. gain probably would have been better if it wasn't like running on ice skates as I have a m6).

You might have a more efficient cam if you wan't to call efficient a ratio of driveability to power but you are leaving some on the table as far as all out power.