mseven

I agree.....there are many others to choose from.
what happens after welding on a lobe, re-staighten? and chrome plating a journal, that just sounds a bit primitive to me..sorry

cv67

Sounds similar to what some of the ZR guys have to do to their bearings (ceramic coating) because they cant get main bearings.
How do you guarantee even coating, and when it peels/flakes off?

stevie1dr

Since I'm the one who owns the cam and ran it in my 89 coupe, I can tell you that it most certainly isn't a re-grind or a welded up cam. It was installed by my engine builder Carolina Machine Engine who built my 383 stroker motor and was brand new. True, it is more of an old school type cam with some overlap, but I can tell you that it performed very well for me, and produced a ton of torque and pulled really well through mid range and up to 5500-5600 rpm's where I shifted. It has a bit of a lopey idle and would perform well with a stick shift car. I turned very consistent times of 8.2 to 8.4 seconds at 85 to 87 mph on the 1/8 mile.

GREGGPENN

Look at the rcommended rpm ranges vs duration for cams. Compare that to shift points and peak rpms. (Also, look at head flow vs lift)

With some digging, I think you'll find cams with more than 220 duration aren't normally considered optimal for use with a sub-6k-shifting TPI. That's because they'd give up power on the low end.

It also shows there's some room for "error" in cam selection. Even if you don't pick the "best" cam for an application, doesn't mean you won't end up with a strong-running, fun motor.

I would also suggest looking at typical LSA values chosen for TPI applications.

stevie1dr

I won't argue with that, but my point was that the cam performed very well for me, even though there may be what some would define as more modern.

cv67

Plenty of old school cams out there that rip...in the right application .

ride250s

Well for now I have decided not to buy the FIRST because I will eventually be running this car on road courses, and I think a higher RPM motor might fit me better. Anyone have input on that? I'm thinking coming into corners with the RPM around 4000, and then really getting on it upon corner exit. Then it would breath better on the long haul straights like at Road America for instance. Or for a C4 (which will never quite be a C5 or a C6), sould I just stick with a lower RPM Torque motor, even for road racing?

-Luke

ride250s

There are so many directions to go with a build... I swear I change my mind every freakin day.

Lemme

Apparantly the longer duration cams have the effect of moving the power band up in the rev range which is what you want for a road racer. The TPI intake and runners would have to be replaced by a "single plane" intake setup such as the superram.

Orr89rocz

Can stick with the FIRST TPI and get the AFR 195 heads for sure. If you throw this on the stock shortblock, i'd have the heads shaved down to 58-60cc or so to get compression back up.

That first will support likely a 5500-5800 rpm peak on a 350 due to the massive runner ports. Port match the base to a 1205 which is ALMOST like AFR 195 ports. Then throw in a cam like the 280XFI. That will give great top end. Peak near 5500 due to the intake but hang on well over 6000 rpm due to extra duration.

Else get a custom grind... road race grind will likely have abit more exhaust spread to have power hang on as rpms climb. If the intake and exhaust duration is large enough however, power will still hang on longer in the rpm range (good for road race) but you may sacrifice alittle off idle and lower end torque. Not a problem if you gear it right and stay in the powerband.

Check out www.jonescams.com, or ultradyne cams (done by Bullet cams now) or even bullet cams for that matter. They will set you up with a great cam. that has potential to be a powerful setup.

Lemme

Operating Range: 2000-6000 RPM
Duration Advertised: 280° Intake / 288° Exhaust
Duration @ .050'' Lift: 230° Intake / 236° Exhaust
Valve Lift w/1.6 Rockers: .576'' Intake / .570'' Exhaust
Lobe Separation Angle: 113°

GREGGPENN

No disagreement here!

If you're a believer in simulations and matching components, look at the simulation below....

This is came from a very detailed EA Pro simulation for a 350 with AFR195 heads. Info on flow/port-size was included.

The red and lt-blue lines are the FIRST intake.
The green and dk-blue lines would have been for my SLP intake (before opting for a 383).
The hand-drawn purple lines would have been my HSR intake.

Until 5500 rpms, you can see a FIRST should out-perform even the coveted HSR. That's due to it's overwhelming advantage in the 3k-5k range. Plus, it hangs on for another 500rpms until the HSR finally wins. Notice too, how small the cam selection is. Finally, notice the TORQUE band for the FIRST really starts to roll-off before 5k rpms. IMO, picking a cam in the 280XFI range (duration), would be trying to improve the MECHANICAL disadvantage for (even a FIRST) TPI. With the stellar flow characteristics of an AFR195, any cam duration acts bigger than ever before. (I'm pretty sure it was you who noticed how small the cams are for some of the fastest AFR195 builds at the track.)

I still think the FIRST/AFR195 combo should be a premier street/strip build option. But, I don't think it should include a cam that tries to get more out of that 4k-6k rpm range. Air flow won't really support it. Why give up some low-range for that?

Look at intakes like the HSR/MR/carbs if you want to target 4k-6k rpms. The FIRST is better from 2.5k-5.5k rpms.

ride250s

Yeah, After a few hours yesterday, I started started considering the MiniRam more than ever. It bolts on a little easier than the HSR which needs to be cut down to fit under the stock hood.

Now I just have to start saving money hahaha.

chrisr0315

Goto Comp Cams website and download CamQuest software . Allows you to enter alot of info for you application and then makes several cam recommendations . Very detailed . even allows you to enter headflow , header size , induction , comp ratio , trans , car weight . then approximates HP and TQ .Y ou can see what sligght changes optimize your intended build . Along with suggestions in cam from excellent to fair choices , it also recommendes all valvetrain parts needed
You have alot of things to consider . This program helps take out alot of gueswork

Orr89rocz

Miniram is so expensive but does work well. You'd be happy either way, but it does bolt on easier than any TPI setup and about the same as the HSR..just have to bolt the plenum on which is an extra step over the miniram.

GREGGPENN

Sorta....

It's a great piece of BEGINNING software that helps you see the basic result of different cams and intakes. Every component would not be represented there -- particularly the FIRST. For an HSR, you have to guess how closely it might compare to the RAM intake(s) listed. Plus, you don't have the opportunity to swap int/exh lopes,,,,etc...

A similar tool would be to look at an article called "Ten Times the Torque". Just as I graphed above, consider overlaying response curves for the various options to see where you'll make power. Also, take SOME consideration about rpm recommendations for the various cams/cam manufacturers.

Getting a GOOD simulation run with EA is way better. If you don't need every last 1/10th, just learn the basics and you'll start to see the obvious. And, as you mentioned, CamQuest can help. Just don't rely on it as your final word.

GREGGPENN

For people who are curious, here another visual comparison.

This is a graph of the SLP vs HSR. More importantly, I looked at actual dynos of stock L98s and quickly drew that in (tan & black). It might help people to see how much heads, intake, cam, and headers will do for a L98 350.

JAKE

When considering piston to valve clearances it's important to remember that the clearances are most needed when the engine is over-revved, valves floated or a shift is missed.

It's during those times that the minimum clearances come into play and are needed the most. Just because the engine will turn over without a valve hitting a piston really means nothing when the spring loses control of the valve.

Minimum recommended clearances may seem excessive and some cheat on them by running less than the recommended amount, but at their own risk. It doesn't take but one time to cause tremendous damage.

Jake

ride250s

Thanks for all the info guys!

ride250s

Well, I changed my mind again and bought the FIRST intake.

After much research online of other builds, and after going over the artical, Ten Times the Torque, several times, I desided the FIRST intake would give me the power increase I'm looking for.

I also partially based my decision on the fact Corvettes raced the Stock TPI setup very successfully for many years in the SCCA Showroom Stock Class, and the Corvette Challenge Class. Having such a great success over the competition road racing with a low RPM, large torque curve, made me realize this thing would be great to drive on the track!


I think I will call CompCams after a few weeks (and after I deside on heads) to get a cam setup just right for me with new lifters.

Is it worth getting new pushrods and rocker arms??

I have kind of read the stock heads in my '87 flow alright, are new heads a must if I want to get the most out of this intake and a new cam?

I already have a good exhaust system (Melrose), check it out:

http://www.youtube.com/watch?v=RQ6iHeQn5VY