Xeryus

Hello all,

First off, I know that the trick flow is a complete top end kit (well, except for lifters) while the RHS is just the cylinder heads.
At first glance, the main differences that I found between the 2 is the intake runner volume. The TF is 170cc while the RHS is 200cc. Also, that the combustion chamber volume on the TF is 61cc, while the RHS has 64cc.
I'm trying to think ahead as I plan this out. After the engine is finished, a Hellion turbo kit is next in line.
Here's my question, how much difference do those numbers make? i.e. will the smaller TF kit (170cc/61cc) hamper me that much more compared to the RHS heads (200cc/64cc)?

Any advice would be helpful. Thanks!

mjr46

depends.......ask ADDERMK2 about rhs vs the trick flow top end kit!!! with a proper matched set up using rhs heads..it'll out perform the tfs kit anyday!!! at best with a tfs kit you may hit 275 -285 rwhp depending on your tune......now one advantage a tfs kit would have is you can use the 2.02 valved head on a stock bottom end without fly cutting pistons.....not sure what valve comes in those rhs's but if it's a 2.02 you'll have to flycut the pistons..ask Adder!! I'm to lazy to look it up

Xeryus

I hear ya, I was kinda hoping that Adder would eventually chime in.
My main concern about piecing it all together is that I don't know enough to be sure that all the parts will fit and work together. I was planning on doing all the buying and having a shop do the actual work.
Tho RHS does offer fully assembled head with almost everything (valves, springs, retainers, seals, guide plates, etc).
http://www.compperformancegroupstore...y_Code=SBF_180
I might go that route, but I'm not sure what else would be needed.

mjr46

well there really isn't much to worry about piecing together ..just choose a cam that'll work with your combo...like what do you want the car to do first off??? street / strip that has to pass emissions??? if emissions aren't an issue then you'll have a broader range of cam choice...but most aftermarket heads have springs for cams on them already for good up to 550 lift......so choose a good cam gaskets accordingly and roller rockers and a double roller timing chain and learn how to properly set up the valvetrain meaning how to check for the proper length push rod needed.......once your engine is assembled to that point where valvetrain geometry and PTV needs to be checked using an adjustable push rod length checker ....you would then after determining the correct length order the push rods....... push rods are usually never ordered at the same time when you are putting together your own kit!! it's the proper way to do it...anyway those are the most crucial things to think about.....if your car is a 5 speed then you won't need the supporting mod of a stall convertor like an auto car would with a cam change

Xeryus

Yeah, the idea is street/strip passing emissions.
Like I said above, I wouldn't be doing the actual assembly. Not an option in my situation; I was hoping to buy up all the parts over time, and then drop it all off at a shop. But I obviously don't want to buy everything only to be told that part X won't fit.
Ugh!

mjr46

well determine your power goals....is your car a 89 and up with mass air cause that'll affect choices, for examplecam choice is more broad for a mass air car than it would be for a speed density car if you don't have a stand alone tuner.........choose an emission legal cam like an e-cam or something similar that carries the c.a.r.b denotation... a steeda #19 cam although it doesn't carry the lable is roomered to pass emissions fine.... rhs heads are a good choice but you'll have to flycut your pistons as I see they have 2.02 valves...and for an intake a edelbrock rpm 11 is a good choice or a holley systemax II is a good one and trick flow has some good ones too ...just pick one that encompasses the rpm range parrelelled to that of the cam like 1500 to 6500...you shouldn't need the victor series = higher rpm's as far as gaskets each manufactorer of the part you buy often has a listing..and for roller rockers it'll depend on the heads..are they stud or pedestal mount..most go with stud mount so order 1.6 rockers based on that.....and match a throttle body to the opening on the intake and maybe with the new combo upgrade to 24 lb injectors and buy or have your maf calibrated to such injectors and while at it upgrage the fuel pump to a 255lph cause you have a return style system so bigger in that case won't hurt......also buy a set of decent shorty or equal length headers if you don't already have some......hope this helps!! good luck!!! gotta run!!

67mustang302

RHS 200 heads are pretty big for a 302. If it's a street car you'd be better off with the RHS 180's, those and a turbo and you'd have an assload of torque in a very streetable rpm range. The biggest question is, what are you building and what are you going to use it for? Also, if you need to apss emissions, then you may need a smog legal head depending on your area. You might want to also look into Edelbrocks new Pro Port CNC heads, they make a next generation Performer RPM version, with either 170cc or 190cc ports.

Xeryus

The goal is to have a lot of HP in a daily driver car. Now, I fully understand that the more work into the engine, the less "streetable" it is. But I have a broad definition of streetable and and willing to put up with more than most; i.e. lumpy cam, etc...
How are smog legal heads different than others?
Let me ask my inital question differently: what is it that makes the RHS heads (for example) better than the trick flows? Considering all the numbers are the same or similar, what really makes it better?

Just a noob trying to learn. Thanks for all the input so far.

mjr46

they have the bosses at the rear of the heads for the air injection tubes!

67mustang302

What makes a good head other than the basics of quality, working the way it should etc, is having a high rate of flow with the smallest port possible, that essentially allows you to be able to get more air into an engine, with higher air velocities. RHS heads are good, the TF TWS heads are ok, but there's better stuff out there. The thing is, if you start going too big with stuff on a street car, you encounter a problem where the parts can flow more air than the engine does, but because all the holes are too large(intake ports, intake manifold, throttle etc) the velocity slows down, and you lose power.

As far as work going into an engine, it actually takes more work(and money) to get an engine to make power AND be streetable. It's easy to get any engine to make a lot of power if you have the money, but getting a lot of power in something that can be driven reliably on a regular basis, takes more effort.

As far as heads, there are a lot of good ones out there, and when you search start by narrowing it down to those that have the best performance characteristics, smaller ports with higher airflows, then you need to look at wuality, availability, cost, how well it will work with your application(and your application will also determine the performance level of the head you get)....all that factors in to why you get one particular head over another. There are many people who get a lower performing head because they bought it from someone for half the price they would have spent on a slightly better head, a deal too good to pass up so to speak.

For a street 302, most heads with intake ports upwards of 180ish cc range will work if you have the right gearing, with matched intake, cam etc, and the larger ports will tend to favor a blown application more. Just remember that as the ports get larger, lower rpm power drops(where you do most of your driving anyway) and mileage goes down as well, so it's also a matter of how much low end power loss you're willing to put up with, and how bad a mileage you're willing to accept.