Straight from afr-1250.00 or TPIS afr worked heads 1800.00 Are the TPIS worth the extra money

 

The AFR price is not the competition version. Add about 600 to the price to be comparable to TPIS. However, the AFR's will flow better :cheers:

 

Whats the difference between the afr and the tpis ---they both use the same afr head

 

TPiS' is fully ported and worked over.

 

Here's the flow bench comparision of my AFR's before and after TPiS worked them over:





[Modified by ELEVENS, 8:24 AM 10/25/2002]

 

ELEVENS, from teh flwo sheet you show, it does not appear that they did very much and actually lost flow at the .400 lift range.

 

Yup. The balance between intake and exhaust was improved to a more favorable ratio, and the open/closed spring pressure was adjusted for my cam. Tells me these heads are very good coming direct from AFR. I did get this cool bench flow table, though! Would I buy from TPiS again? Probably not AFR heads, but the rest of their product line is pretty good.

 

Lingenfleter says to look for a optimum 75% - 85% relationship between exhaust and Intake flow at the same lift. Stock D-ports are 82% .

Divide the exhaust flow at say .400 by the intake flow at .400 = efficiency .

I just may leave my stock D-ports the way they are.

 

Looks like straight from AFR is the way to go

 

I know this is completely off the subject of the original post but I just saw this and had to take minute to answer.

If you want the most power you can I would still advise you you to port them. Even the best design can use some help, even if it's just smoothing things up 75-85 percent is a fairly large margin and is fairly easy to stay within the limits. Take this example, I know a guy who had some LT1 cylinder heads hand ported by some guy who is the self proclaimed god of performance. His numbers were as follows for the intake, these are .100, .200, .300, .400, .500, & .600

70, 130, 182, 225, 244, 239

the exhaust flowed

52, 100, 134, 165, 188, 203

exhaust percentage of intake was (rounded)

74, 77, 74, 73, 77, 85

Now these flow numbers are pretty much terrible, only marginally better than stock but you can see it's fairly close on the exhaust percentage of intake, maybe a little bit low. This car dyno'd 336 horsepower, exactly what I dyno'd on stock heads even though this guy had a 232/242 cam vs my 218/228. He has a slightly higher lift as well and they are both ground on a 112 LSA. He had his cylinder heads done by TEA, before I worked there BTW, and put them back on. He retained stock valves and got the following flow numbers on the same flowbench as above.

Intake

63.2, 140, 195, 235.9, 255.3, 253.1

Exhaust

48.2, 109.3, 154.3, 185.7, 209.6, 224.4

Percentages

76, 78, 79, 79, 82, 89


The car dyno'd again, on the same dyno. This time it made 391 hp. Suddenly that larger cam came to life huh? My heads which technically flowed more because of the larger better valves only made 365 hp with my cam. In any case that's an insane difference due to heads alone. Meanwhile the percentage numbers, although changed are still well within that range. So what am I trying to say? Although that relationship might be very correct for making peak power, it doesn't mean everything. Unported these heads were very close to making the optimum relationship and they performed terribly. After they were ported they fit the optimum relationship and made over 50 more horsepower with nothing else changing. 75-85 is a fairly wide margin and easy to work with. I would look more towards something tailored to your application.

In this case the heads were obviously the restriction. His cam performed no better than mine when choked by heads that no matter how poorly actually outflowed my stock ones. As soon as the heads were worked on he got a huge gain. Certain parts truly work together to make a total package and must be looked at. Just because your heads might have a good intake / exhaust relationship does not mean they will be able to flow enough air to feed whatever cam you might choose.

BTW, my heads had the following relationship 79, 76, 80, 79, 81, 87
As you can see pretty much dead on with the stock valve head above but I still made less horsepower. That's ALL in the cam. Do your research and see what you can find out about the total package you are going to be running. ld85, from our previous discussions I believe you are really going to want some heads before you are truly happy with your setup.

Hope this helps

:cheers:

 

Nathan, I am still picking and choosing parts so I will know the final output come when its all said and done.

And I agree you wouldnt want the cam be to large for the heads or the heads to restrict the cam. Or the exhasut restrict the heads or the intake restrict the heads etc.

Any word on the porting quote?

 

Yeah, I had a big long message typed up to you the other day but our mail server was screwed up and I couldn't send it. I'll send you an e-mail shortly.

 

Tks for your post---my setup will consist of ---super ram ---lingenfelter 219 cam and the afr heads. Im trying to put everything into its proper perspective as this is really my first attempt at putting a super engine together in about 30 yrs. Alot has changed thats why im doing this a step at a time and doing a vette is not like a simple carb sys. Money isnt the objective but putting it together right the first time sure is. thanks for your advise.