What Heads with RPM II?

[USAF91GT]

Alright, as the title states. Did a fair share of searching but couldnt find much as the search function will not include the "II" part.

Anyhow, got the mods in my sig as well as a CHP 306 with forged slugs on the engine stand. I would like to stick with the RPM II because I have it already and really like it, even though most are running AFR's with the Performer set up and see great numbers. I also really thought about the Edelbrocks just to keep the same brand, but the flow #'s leave a little to be desired compared to others. Going to be mostly street driven as a D/D so I am not sure if I should go with the 2.02 or a 1.9 valve setup? Torque is important, not interested in revving it past 6250. I know, I know, the intake was prob. not the best choice but I want to work with it.

Have the money so a custom cam is probably on the list after deciding on heads.

Thanks for the help. I know I am new here, so go easy

 

[DMAN302]

Tad big...yeah, but still a fine pc. You MAY loose out on some lower mid range, but I wouldn't worry. I run the Eddy RPM heads 1.9 valve with a comp cam and love them..they were quite a bit cheaper than AFR's and after being massaged a bit are just great throughout the 2000-6000 rpm range..building all the way up.The flow numbers when compared to AFR and TW heads might not be exact (really not that far off with the new Eddy versions) but the HP developed is quite simular with all big name heads today.

 

[USAF91GT]

The Eddys do seem like the easiest choice, and I have read that the Eddys really shine after exhaust port work, but I know porting is expensive. I have roughly $1600 to get a cam and heads and want the best one that would work for me.

In my case would any 1.9 head be the best choice? Eddys or AFR's? Don't really want to bolt some Wedges to a Eddy intake, just doesnt seem right??

 

[DMAN302]

Well you'll need to get porting prices, my builder tackled the grinding on the heads a quite a discounted rate but either way it's not that expensive. Your issue here might be that you have a high RPM intake and you may need to upgrade the springs in the AFR heads to make full use of the upper RPM range available to you..that put the AFR heads out of reach $$ wise for me. I would recomend the AFR 165's or the Eddy 1.9 RPM's...but again it's just opinion.

 

[USAF91GT]

Yeah, didnt really realize that about the RPM II when I bought it last year. Although, Edelbrock claims that it does not lose any torque to the regular Performer and now that I have never used that one, I have no complaints about the RPM II's Performance. Now granted I just have the basic mods, but I feel my car has great bottom end performance, as well as a noticeable pickup in top end. That might just be Edelbrock propoganda filling my brain, but it really seems to be true to their claim. Now matching port volumes and velocity and all to heads is where I am drawing a big blank as to what I can work with. You peaked my interest though with the smaller valved heads. Google here I come.

 

[USAF91GT]

Anyone else?

 

[USAF91GT]

What about some Edelbrock Performers with 2.02/1.6's with a custom cam. Could this give me what I am looking for while saving a bit of money at the same time?

 

[2000xp8]

If this is a street car there probably isn't going to be any head NA 306 that will need the supply of air an rpm II puts out.
As said above, you will probably lose low end, which makes for a bad street car.

If you really want to try and make use of it. Some Cnc'ed wedges, afr 185's

I'm about to rid of a like new Rpm intake maybe 3000 miles or less on it, let me know if you want to trade intakes, and i'll give some cash. 347 going in very soon.

 

[5spd GT]

If this is a street car there probably isn't going to be any head NA 306 that will need the supply of air an rpm II puts out.
As said above, you will probably lose low end, which makes for a bad street car.

If you really want to try and make use of it. Some Cnc'ed wedges, afr 185's

The little he loses does not automatically make for a "bad" street car.

He has already stated that he knows it isn't the best choice, why keep stating it...derek and him have already got that straightened out.

good luck with the stroker...

 

[Rick 91GT]

You can go with a custom cam to help compensate for the RPM II, adding a spacer to increase the runner length may help also. This will be a little over your $1600 goal

AFR165's $1325 or TFS Track Heat $1270
Custom Cam $325

 

[DMAN302]

Ricks info is some of the best you'll find on the net..as a new member I would really consider his input as some of the most valid you'll come across.

 

[USAF91GT]

Well, thanks alot for all of the replies. Just trying to get my brain wrapped around everything before I swipe the ole debit card. I did notice though that the AFR 165's do flow more than the Edelbrocks (even with 2.02 intake valves) so I was pretty impressed. I would like to use an AFR head because it is different from everyone elses. Maybe not on here, but on the streets you dont see them very often.

So Rick, I have followed and read a lot of your posts in the past, so I do value your opinion highly. To get it straight, are you recommending the 165's for my setup? That is kind of what I was set on before starting this post but wanted to see if I should go with the 165s or 185's. It is very important though that this car remains a streetable D/D. A little over my goal is OK for me. Never gonna be right on budget, but I am concerned that a custom cam MAY require a spring upgrade on the AFR's, which according to their site is $175. Any thoughts on that?

2000xp8, let me figure out if this one will work for me. If not, you will be the 1st to know. Thanks

 

[Rick 91GT]

The 165's are a good choice if your a street car, small cube, under 6000rpm. If you have a blower or turbo or stroker in the future the 185's would be my choice hands down. Yes most likey a healthy custom cam will require a spring upgrade, I prefer to use a different spring and not upgrade through AFR. My aftermarket springs and Viton seals package, seals are required so they fit the ID of the new spring are $200 installed.

I would assume you have a Probe piston in the motor what PT# is scribed on the top I can figure out what you have compression wise.

 

[90lxcoupe]

you might be able to get a set of AFR 165's used, i know a kid on here that is doing a dart block and he has no use for his AFR 165's and he had very little miles on those

 

[USAF91GT]

Well Rick I am a few thousand miles away and one Pacific ocean from my shortblock. Wish I could go out and look at the P/N.
However, from CHPs website for the 306 Street Fighter it just says "Probe SRS Flat Top Forged Pistons" I know I didnt specify anything other than stock CR when I ordered it, so I am actually sorry to say that I really dont know?? From their site, they should be 10682, which gives me a 9.5:1 CR with a 58cc head, should be around 9.3 with a 60cc head. Seems pretty good to me, just slightly higher than stock.

Oh, and no stroker or blower in the future. Maybe some spray, but my N/A choice will not factor that in at all.

 

[Rick 91GT]

The 165 would be my choice....

 

[USAF91GT]

Thanks for everyones input. I am going to throw this all around and see what I come up with. Still looking into a few other options and combos that have come up.

Thanks alot for the help Rick, from all of your posts I read you seem like a real stand up guy, and your recommendation will prob be what I end up going with. This is exaclty why I came to this site, to get some input from those who really know. I will let everyone know the outcome as soon as it happens. In the meantime, feel free to post up just in case anyone else could use this information.

 

[USAF91GT]

Ok, one other question. Over on the corral, a guy posted up who was running the RPM II, and some TFS Track Heats and was putting down some pretty good times. After comparing the Track Heats to the 165's, it seems the numbers were pretty close on the flowbench. Would these be a viable alternative considering they come with springs good up to .600 inch? The mid lift flow #'s are pretty impressive, and are cheaper than AFR's. Not particulary sure what the increased valve size will do to my combo as far as port velocity and all.
The smaller valved AFR's did exceed them in some areas though, even with the smaller valve. Engineering on the AFR's must be killer.

 

[5spd GT]

I think you are making the right choice...by the way the pistons you said are the same pistons I have in my car...and guess what, I have the 165's... Getting track times in a couple weeks...

That gray86 guy has good numbers because look at his race weight: 3100lbs and hi 60ft. He has some pretty serious suspension work and the car was obvioiusly track oriented...ask him what accessories he has as well. Probably has lost a couple of those on the way...

 

[aleborjas]

i would run some TFS TW's or AFR 165's no bigger than that because you have to much flow up top with your intake and if you dont whant to go custom with the cam get a comp cams xtreme energy they are very good on low, mid and top torque, i would run a XE266HR-12 (#35-514-8) and if you whant more rpm's get XE274HR-12 (#35-518-8)