That is not fair and I would like them to express what is going on.`

 

Interesting guys,

Ok, I don't know where you guys get your information. First of all the valve area of a 2.080" valve is enough to theoretically flow over 335 CFM in a 23* head configuration. This runner was the result of over 4 weeks development time every day ALL day by people who know what they are doing. I am offended to hear someone say they only flow 280 CFM when I am the one who tested the darn things. In testing the heads needed a proper entry or yes they would become turbulant, this is not due to the runner being wrong, but due to the size of the runner itself. I was getting airspeed over 495FPS in some areas in this port, and if you think about it that will equate to well over 300 cfm given the port size. I know you are in school now guys, but I assure you, there is alot to learn outside the halls of SAM, it is a great start and you learn a TON but I have worked for a few reputable shops, one in particular for allmost 2 years, ED Pink Racing Engines. This company represents one of the best engine builders in the country, we were getting over 3hp per cube naturally aspirated from those Infinity Indy engines and the heads were amazing they were a runner just barely over 180cc and these things flowed over 450cfm, and the only way they would do it is with the proper entry, in this case, the intake runner and true venturri at the proper angle. These heads are the same way, and when we discussed chuck building a sheetmetal intake for this engine we TOLD him the stok intake would not do it, it is not the right angle of entry to match what the heads really want and if he wanted to get all they had he would need to get a manifold custom made to suit the heads preference. In testing we actually built an entry from various materials around the shop to get the heads to stay stable. Look if you ask me for the smallest runner I can make and want the best flow numbers, there is a small price to pay to get the results you want. I also still feel there is more in that engine, simply based on what Bob Smith's car put down. AGAIN, HIS CAR MADE OVER 530 AT THE CRANK WITH FULL 2.5" EXHAUST, 4 MUFFLERS, 2 POINTS LOWER COMPRESSION, LT1 EDIT WITH STOCK INJECTION, A RADICALLY SMALLER CAM, AND AN INTAKE AND HEADSERS DESIGNED TO FIT THE CONSTRAINTS OF AN ENGINE BAY. You can't argue with results, PERIOD. There is also another set of heads out there that I am anxious to see what they do, they are also on our bottom end again with the same smaller cam. I will keep you all posted about that engine as well.

Just out of curiosity, is there a Flow Com on the flow bench at the school, and are you using it? It sounds like you are still doing the calcs by hand, if that is the case, air temp, humidity (heavier/lighter air), baro (more/less atmospheric pressure), ETC ALL play a big role in this flow thing, and if you are not correcting for these things you will get erronious readings.

Sorry for the long post but I need to make sure my customers know the real deal.
Bryan Wolter RPPE Inc.

 

Just to add to Bryan's statement, that hp figure was with a VERY cold cylinder due to a bad Optispark. This has been corrected, and while it has not revisited the dyno since, the car pulls substancially harder than before.

 

Here's what I think... I think I just hit the limit with the heads, and Bob still has another, oh, say 30 hp he can gain before he hits the limit too. But that's just my opinion.

Also remember, if we're going to compare my engine to Bob's, don't forget to mention his motor is almost 400 ci, and mine is a 383.

And fwiw, you're not talking to SAM "students" here. I'm the only one that qualifies as a student, but I graduated a month ago, so it's not technically correct, but I'll be the first to tell you I still have a lot to learn. Erik is an instructor there, and has been for a few years I believe. Casey runs the head department there, and has done work for both Lingenfelter and GM I believe involving Gen III heads...

Like I said a minute ago, I'll be the first one to admit I've got a lot to learn. So just bare with me as I ask a stupid question (to which I already know your answer, but I'm just going to state it nonetheless).... Most of the people I've seen flowing heads, only use a some sort of radius to smooth out the port entry. Why do your heads require such a specialized entry to flow as much as they do? How then are we to compare your numbers vs. another set of heads that was flowed a different way? IMO, from what I've seen, a heads flow numbers with a clay radius will generally add up to what the motor makes on the dyno. These heads with a clay radius, added up to what they made on the dyno. With the improved intake, we can assume the hp numbers would in fact improve. But are we not also to assume that an improved intake on a head that flows 320 cfm with a clay radius will not make more power than a head that flowed 287 cfm with a clay radius? Just my opinion...
Chuck

 

Chuck,
The reason the heads need the better entry is because for your application we decided to make the runner as small as we possibly could because you were very concerned with velocity. When we talked, you were leaning tward the sheet metal intake as your choice so we opted to give you the heads again as small as possible to achieve the flow we wanted. I would not have given them to you that small if I thought you would not put the sheet metal intake on them at all, as I recall, you were going to run the stock one for a while then switch to the better intake once you had the money. I can and have gotten over 325cfm out of that head with the same runner size and simply opened the bowl area up to help quell the turbulence at the short turn induced by the sheer speed of the air. I achieved a head that requires no special intake of any kind by slowing the air and still kept the velocity through the runner as good as yours, it simply helped the air make the corner, where as the entry on your helped set it up for the turn before hand this mod only adds like 3 or 4 cc's and is now my current port configuration. Like everything, heads are allways a work in progress and there is allways a way to improve on your design.

I will however continue to disagree with your problem with your heads. If you think the Compression, Exhaust, Cam, Injection system, ETC. will only amount to 30 HP I think you are SADLY mistaken, the compression alone would be worth about 60 HP
and what do you know, that leaves cam, exhaust, injection, to make about 30-40 more HP. I hope you see that if I built an exact replica of Bob's engine with your mods it would FAR surpass the figures you are getting. I am not trying to pick a fight, again I simply am standing up for my product, and want my future customers to know that we DO NOT, and WILL NOT "SCREW" anyone in this business. We have a very good reputation going and I will not let one customer that thinks he or his friends are GOD make a blemish on a perfect record.

 

Alright, so refresh me here, 2 points of compression is worth 60 hp... I guess I really do have a lot to learn. Not saying the motor you built for Bob's car isn't better than mine! I'm sure it is, because this motor is the first motor I've ever built! So I mean, I would hope there's some power left in it. But still... It's as good or better than the average engine out there being built by 90% of shops in exsistance (because as you well know, there are more people out there building bad motors, than there are building good ones). I just don't think you can tell me that my building of the motor is the cause for it being 80-90 hp shy of what you are saying it is capable of.

Also, I just remembered one thing that we figured out awhile back after dynoing my motor... The exhaust on the dyno wasn't sealing up at the time, and we had some fumes in the room... which could easily have brought the motor down a few notch's of what it was actually making...

Chuck

 

I used to use Rob’s bench to flow heads and I had him replace some valve seats and do some minor work for me.. Rob's a nice guy and all, but there's all kinds of good stories about Peak from the local crowd. Pistons installed w/ no oil rings, shaving left in the motor, an LS1 that had to be redone twice.

 

As the moderator, I've let this thread go because there is some interesting "tech" content (and we're all voyeurs at times ).

I believe there is little benefit to be gained by the gratuitous, condescending personal attacks (no, not ALL of us here are "students"). You have a right to defend your ethics, but you do not have an automatic right to be condescending and insulting.

I have a couple choices here.... 1) shut it down, 2) edit out the petty name calling, 3) or assume everyone including will start acting like adults.

How do you want it handled?

 

Chuck I am sure you did a fine job of building it, I am just saying you may not be using what you have to the fullest extent. It usually takes more than one try on the cam to get it perfect.
and again I am confident the heads will make what you wanted, and yes at that compression range each point is worth about 4-6% from our findings.

 

Alright, that's fine. Sorry for the mud slinging. It was not my intentions for this ever to go this far, or for that matter, public. I actually wish this thread had not been revived, as I had already become unconcerned over the subject. But I appreciate your concern, and again apologize for everything I have said that has offended you. I realize you have a business to stand up for, and I would do the same thing in your situation. Good luck and all the best.

Chuck

 

Thank you Chuck,
We appreciate it and Good luck to you as well in your new career!

 

Chuck I think you are far from maxing out you heads, as my LT1 heads only flow 276 cfm @ .650, and my 370 makes in the range of 630 FWHP. My heads only have 2.00 1.56 valves, I only wish I had some of these lt4 2.08 valve heads that flow 310+, I think I could make near 700 hp.

 

forgive my ignorance, but are you complaining about the numbers while using an lt4 intake?

i was under the impression that the lt4 intake (even ported/welded) was going to be a bottleneck at this level n/a.

 

Bryan and others, I have seen this stuff unfold over and over and I think the heads were alright just that they weren't moving the air that Chuck thought they would which worried him. He was very pro Race-Prep as well when he came to SAM and he really doesn't bash you guys ever. He was just disapointed in his particular heads.

Casey IS porting them further and we will see what they do with the LT4 intake. I've seen more from the LT4 intake so we'll just have to wait and see what happens when Casey is finished and the airflow is picked up. For all we know the engine may drop but I've never seen that so far. It's one thing when you are way up in airflow and the ports are way too big and they have little velocity where you need it. I think for the 383 Chuck will still pick up with the additional airflow.

Not saying that you haven't seen it but I have never seen those kinds of gains (60 hp) going from 10 to 12 to one in compression ratio unless the cam was installed way wrong. With all else equal

 

Sorry man, after what you told me and a search I did that brought up this thread, I thought it would be interesting info to have on the board.


Cheston
hopeful future SAM student