[Ed Curtis]

Ed,

Here goes some more reverse cam BS:

410rwhp/389rwtq out of stock LS1 heads:

http://jason99ta.slowcar.net/tr230_224_openheaders.jpg

They opened the headers and popped 6" extension on the collectors.

The car has not had the computer programmed yet.

Probably makes sense on a car where exhaust flows nearly same as intake.

This usually happens on ported gt40 heads or ported stocks - heck the exhaust valve is dang near the size of the intake.

Don't kill the messenger.

Dennis,

1) It's not the theory of reverse profile camshafts, but the application of it.

The AFR flow numbers listed are FALSE, period, and a camshaft profile designed using these figures will not perform.

I VERY recently tested a set of these magical TW heads and they were not even close to the numbers the customer was told, pipe or otherwise. As a matter of fact, I told my customer to go to this shop because I felt they had a decent TW program so why would I try to flame these guys? The end result was that I was not too happy with the BS figures given to the customer but the workmanship was good.

2) Look, I've done my share of these high intake/low exhaust duration cams before and will continue to do this. It's just that some people feel it's the end all for the FoMoCo market and it's not. Each application is different.

3) As a side note, the LS1 with 348 inches is doing very well getting 400+ rwhp on the street. It takes a sserious 306-310 inch Pure Street type engine to beat that figure. What I notice on those sites is those guys will spend $$$ to get these results. That's the difference. A $20,000 used 2001 Z-28 vs a $5500 Mustang 88 LX??? Imagine the differences in the budget the two car owners have!

I really can't tell you how many times I see on the Corral "Who's got the cheapest prices on XYZ" and such. I'm still waiting for the "Money is no object, who's the best" type of post here. When I do, you can be sure I'd say build a 355/358 inch, B50 block, long rod stroker for LS1 thrashing duty. They kick ass.... That'll never happen though because that's one of those "bad" oil burning combinations, right?

4) Also, the end all comparison between TW 185 vs AFR 185 is NOT going to prove anything. This is a topic I beat to death months ago and it just won't end. Totally different heads, totally different cross sections and as I alway try to explain.... the TRACK is the proof, not a flow bench or dyno.... Try it.

We prove our point at the track all the time...

Have fun with this one guys....

Ed

 

[noslofoord]

why wouldn't you have the 185's ported???????
the ported TW's aren't THAT much ahead of the 185's. i would think the AFR'S would spank the #'s of the TW's after porting. my RPM's got 50+ cfm from an awesome port job.plus having to flycut with the motor assembled. i know people do it all the time...but imho, it scares me.
porting / milling the heads to 54 or less cc and porting the rpm intake would easily get you past the 400rwh mark. mine are at 51cc's...that works out to 11.67 to 1. i won't be driving mine to work much,maybe;so i want lots of comp.
i'm shooting for 400 at the wheels on motor.

 

[STREETPOWER EFI 331]

I agree comparing 185cc TW's to 185cc AFR's isn't fair because the cross sectional areas are much different due to the TW being ~ 3/8" shorter intake port.

I'm just looking for results.

Most likely I'll either get my 185cc AFR's worked pretty aggressively or sell them and buy 205cc AFR's because I really don't look forward to flycutting the pistons with the motor in the car. I was entertaining the Stg II TEA TW's because it looked like I had a chance to get a set for a good deal. But that doesn't quite seem to be happening. So I'm back to porting the 185's or buying 205's.

Still undecided on the intake although I think the Holley with some strategic porting/straightening of the lower runners will allow 400rwhp peak and the best power under the curve up to ~ 6300rpms.

But I'm probably gonna wait til after some of these combos currently undergoing changes on the board get completed. Like BIGMIKE's 347ci/205cc AFR/Vic 5.0 combo or LX4PLAY's 331ci/TEA TW/Holley combo. Like I said - I don't particularly want to try something that hasn't been done before and proven to work.

 

[trey193]

Streetpower, looking at your sig I see that U Run Nitrous. Ask Brian which head is the better Nitrous head, and he will tell U the AFR hands down. Not sure what your actual goal is if its just to make 400rwhp or what, but If I had your combo making the numbers it does I wouldnt yank the AFR's, maybe if U were class racing it and the competition was getting away from U and changes were needed then maybe, but most likely comparing a ported TW to a Ported AFR there is not going to be much difference and the AFR will run away on the bottle!!

 

[BigDaddy LTD LX]

Another dyno to whet you 331-351 guys mouth:

http://www.thunderracing.com/images/chris_gtp1.jpg

The bottom curve was stock headed all boltons, etc with 224/224, 565", 112lsa cam.

Top curve is the addition of some stage II ported stock heads, that flow similar to the tooley TFS TEA III's...

With Vic 5.0 intake, 347 cubic inches, AFR 205's, these numbers should be crushed.

 

[STREETPOWER EFI 331]

BIGDADDY-

But isn't the Holley intake closer in runner length than the Vic 5.0 to the LS1 intakes? I believe the Holley is 12.5" runner and Vic 5.0 is 11.0" runner. Add to that the Ford inline head port length which is what - 2"-2.5" or so? That comes out to about 14.5" total for the Holley setup or 13.0" for the Vic 5.0 setup. And I think you've said the LS1's use 15" runners. Right?

 

[BigDaddy LTD LX]

Talking runners only in the intake -

14" for LS1 intake manifold. Uses circular cross section that flows 265CFM. Figure about 1.8" cross. Large plenum.

The ford head is 4.5" long usually.

I believe the holley is more like 16". I do know it signs off too early to compete.

The Vic 5.0 is said to be 11 or 11.5". There is a 1" spacer which can take it to 12".

LS1 intake manifold guys are having problem with intake shutting down @ around 6500 on a 346. They really need a 12" intake over there. Right around what the vic 5.0.

The vic 5.0 was engineered with more modern engineering techniques than the holley, has a better runner design and can be ported to support 700HP N/A.

Personally I think you guys are spending all this time chasing 400rwhp, low 400rwhp at that when the answer is right in front of your eyes.

 

[N2O88]

Its not hard to hit the numbers, people just have to be smart in their choices, and $$$ does matter. The problem with the afr 205 in these comparisons, is that its a raised port head, something the tfs' aren't....and its something that makes it obsolete in some classes (like the psca's limited street class for us west coasters, www.pscaracing.com). I agree that big numbers can be made from a streetable 347 inch motor with the proper head, exhaust, and intake choices.....but it takes some thinking, and some $$$ for nice heads.

 

[BigDaddy LTD LX]

I'm figuring once they get it figured on this side,
there will be 410-450rwhp 331-347's with regularity.

If those guys can pop off 440rwhp and they are even intake limited, then the ford guys can too with the right parts choices.

Care to comment on the runner length questions we had?

Like to know exact runner length and cross section of:

gt40
edelbrock
edelbrock rpm
holley
tfs street
tfs track
vic 5.0

think regular edelbrock is 18", and edel rpm is 16.5" and vic 5.0 is 11".

Not sure on the rest.

The holley is a big piece of material. I wouldnt' be surprised if its runner is 16-18" long either. I think it lets the tq peak be so high because of the massive cross section.

 

[Axoman]

Big Daddy -

TFS Street
15" runner
1.2"x 2"

TFS Track
12" runner
1.2"x2"

TFS R
12.2" runner

2.38"x1.38" upper to lower
1.2"x2" port size at head

 

[BigDaddy LTD LX]

I thought the track was only 1" shorter than the street.

 

[Axoman]

Those numbers were taken off of Trickflow's website.

 

[Blk88GT]

All the bench racing in this thread is hurting my brain!

 

[gregm]

BigDaddy LTD LX

What do you think about my combo. The only part that hasn't been bought is the heads and Pro M77.

KC331 (mexican block), AFR 185's (61cc, 3/8 stud, boxstock), 10.2:1-10.5:1 compression, custom Buddy Rawls emissions legal HR (small base circle) cam (got to pass houston smog), 1.6rr, 1 5/8" BBK longtubes w/BBK catpipe, Holley intake (or I also have a 302 truck lower that's fully ported and also a cartech upper), currently have 65mm tb but can get a 70mm, 30lb injectors, Pro M 77 and so on.

Sub the AFR's for Stg II ported TFS, 58cc. I've got a line on a set that's brandnew w/flowsheet. Reportedly they flow 298cfm on the intake @ .600" and 212 on the exhaust @ .600". Don't know the specifics like type of bench or entry or exit tools used. Should know tomorrow. Cost will end up being within $100 of each other. Heads are ported by a local reputeable shop.

So would the TFS be better or the AFR's? Buddy has been directed to give me the ingredientst to pass smog and allow me to spin to 6300 +/- 200rpms. Most likely duration for the intake and exhaust will end up in the 222-230 range @ .050" and lift around .550ish". The tweecer will be used to "tweak" for best performance.

Thanks

 

[Billy Edwards]

I thought the track was only 1" shorter than the street.

i'm thinking they changed, earlier ones were 1" shorter, later models have a 2" difference.

I think the 18" for the Edelbrock seems pretty high, i was thinking more like 15" for Edelbrock Performer, GT40 and Cobra all roughly the same, but the FMS intakes have a smaller area. I've heard the RPM has 13.5" runners, but I've also heard they're 1.25" shorter, but those estimates both come out to close to 15" and 13.5". The Holley number I have is 13". I just went out and measured my stock intake, 9.5 roughly in the upper, and 5.5 in the lower. That's 15" for the stock.

Billy

 

[BigDaddy LTD LX]

Well maybe there is a problem with how the air moves on the ford intakes, so that runners starve others.

 

[86Cobra]

TFS redesigned the Track Heat last year. It now has 12" runners versus the old 14" runners.

 

[BigDaddy LTD LX]

So a good ported track heat will be worth something.

I guess at that point the "R" makes sense.

Do you know what the track heat would be worth?

 

[86Cobra]

I'll find out in a few months. I should be up and running in June and I'm going to run it stock on my new setup for a few months. Then I plan on sending it to Tooley for a full port.

My cam is ground to shift at 6600 so a ported Track Heat should work well. I'd love to run a Victor 5.0 but I think it's too big for a 6600 rpm 306.

 

[jb1kanob]

Just a note....I firmly believe in not porting heads extensively. Now, I know that race shops do not want to here this, but these stage III, IV, V jobs are effective, but not necessary in all cases. I would go with a set of out of the box AFR 185's or 205's vs. having shop take away from the cnc porting. Head porting has become popular because stock heads are often times restrictive. Also 'old school' aftermarket heads tend to be very rough as a casting, lending to 'port work' to make them flow decent (think World Windsors). Shops like to sell these stage port jobs because first and foremost they make a lot of money doing them. Just my 2 cents. John