[grivera]

Originally Posted by Pontiac Derek

Or an RPM if hood clearance is not an issue

The FiTech is a square bore and the cast iron I have now has an adapter plate to accommodate the system. Re: the RPM, will it accept a square bore TB and is it easy to separate the water crossover for port alignment? Isn't the water crossover in an RPM connected to the runners on the driver's side?

[Mace1971]

Originally Posted by grivera

The FiTech is a square bore and the cast iron I have now has an adapter plate to accommodate the system. Re: the RPM, will it accept a square bore TB and is it easy to separate the water crossover for port alignment? Isn't the water crossover in an RPM connected to the runners on the driver's side?

Yes, the FiTech will work perfectly well on an RPM with only a slim 0.125" plate to allow it to seal properly vice the thick square-bore to spread-bore adapters. Also, separating the crossover isn't a problem, just takes a saw and then some grinding.

[grivera]

I have access to a nicely powder coated RPM manifold but if I have to cut and grind it will ruin the finish. Does the process allow for touch up?

[Pontiac Derek]

No it separates pretty easily, look at my stealth RPM thread I made, square only? Are you sure it doesn't have both bolt patterns?
If you use a single plane use a Torquer 2 not a tomahawk knock off, or a 4150 pattern Warrior but those are harder to find.
When I mean Port an intake Port Match is just a part on the work, I port the carb flange to plenum/runner entries, I equalize the flow between runners as much as possible.
Look at TAMAN's thread about running 11 flat at 123.6mph with 3.08 gears there is pictures of my port work there

[Pontiac Derek]

http://forums.maxperformanceinc.com/...d.php?t=784792

[Mace1971]

The FiTech and RPM each have both square and spread bore bolt patterns. While the TB will bolt to a stock manifold the intake flange would need to be machined otherwise you need the thick adapter. The RPM needs no modification, the FiTech bolts right on with just the thin plate.

[Tom Vaught]

Originally Posted by Pontiac Derek

The Victor has a Much straighter shot at the valve, it's hard to beat, but it also is hard to fit under a hood.
My Personal favorite because I am Nostalgic is the Warrior. It's just so sexy. The curved runners are awesome. There is better intakes but none that look better! Imho, but not enough plenum and any time the runners curve and are not making the straightest shot possible it's probably not going to make the most power, jmho

The "fix" on those intakes was exactly what you said.

I have seen several Nash 4 bbl/Warrior intakes that had a 1.0"+ volume added to the bottom of the intake plenum. Not noticeable, but helped with the tuning. Some guys even put shields on top of the runners to disguise the added volume.

The runner can still draw Fuel/Air mixture even with a lowered plenum. Food for thought.

Tom V.

Compare Post #19 (Steve C's dyno data) to the Fulper link attached. http://www.pontiacengines.com/Chinese%20Intake.htm

Intake was called Tomahawk by the Pontiac Vendor in Cali. Called Hurricane by the American import company who was selling the same intake and competing against the Pontiac Vendor. Pontiac Vendor was buying the Imported Chinese intake and just used a different name.

[HJones1313]

Originally Posted by Tom Vaught

I was involved with the original Holley Street Dominator program when Holley released the HSD intakes to be better than the very expensive Aluminum RA-IV intakes and mount a Holley carb without a adaptor. The intakes out of the box were an actual 3% better vs the best RA-IV intake we tested (several). We never had cracking issues with the intake.
Herb Adams ran the intakes on his Fire-Ams. I have owned several of them with no cracks.

The Tomahawk was a Chinese made repop of a properly Ported HSD Intake owned by one of the members of the PY Forums. That manifold was used as the model for the Tomahawk intakes.

I would agree that if the part number was ground off the intake was probably a "retrieved out of the dumpster" intake sold on E-bay for some cash.

For what it was designed for, the HSD can be a very good street intake (when ported) with a Holley carb installed.

Tom V.

I've been running a HSD since the late '80's, and over the years have performed some mods, limiting any runner work to simple port-matching. Now the motor has been equipped with a FiTech EFI system, I'm curious whether runner modifications will provide any improvements. I am neither a machinist, mechanic or engineer by trade, although I have ported four sets of heads (all Pontiac). In other words, can I do more damage than good if I take the die grinder to it? Will the EFI make any gains (if done correctly).

[Tom Vaught]

Originally Posted by HJones1313

I've been running a HSD since the late '80's, and over the years have performed some mods, limiting any runner work to simple port-matching. Now the motor has been equipped with a FiTech EFI system, I'm curious whether runner modifications will provide any improvements. I am neither a machinist, mechanic or engineer by trade, although I have ported four sets of heads (all Pontiac). In other words, can I do more damage than good if I take the die grinder to it? Will the EFI make any gains (if done correctly).

Because the FITECH efi system is a Throttle Body type injection system and acts like a carburetor controlled by electrons vs Physics, there will be fuel and air in the intake manifold/runners.

Polishing the runners and plenum just causes the fuel to drop out of suspension when it contacts the smooth walls. Now you have lost some control of the fuel distribution.

If you leave the runners, as cast, (or with a slight rough texture after porting similar to the as cast finish), then the air flow will act like a carb deal and be happy. .

A hard acceleration and the fuel is normally pulled off the walls of the plenum and runners, and then is quickly replaced by the pump shot fuel. The right amount of pumps shot fuel and the engine never hesitates on a quick WOT.

With the TB injection, the EFI has to have a Pump Shot Calibration so that it also does not have the hesitation.
Polishing the runners or not putting the wall finish back on the runner walls after porting just screws stuff up, be it EFI or carb.

Hope this helps.

Tom V.

[HJones1313]

Originally Posted by Tom Vaught

Because the FITECH efi system is a Throttle Body type injection system and acts like a carburetor controlled by electrons vs Physics, there will be fuel and air in the intake manifold/runners.

Polishing the runners and plenum just causes the fuel to drop out of suspension when it contacts the smooth walls. Now you have lost some control of the fuel distribution.

If you leave the runners, as cast, (or with a slight rough texture after porting similar to the as cast finish), then the air flow will act like a carb deal and be happy. .

A hard acceleration and the fuel is normally pulled off the walls of the plenum and runners, and then is quickly replaced by the pump shot fuel. The right amount of pumps shot fuel and the engine never hesitates on a quick WOT.

With the TB injection, the EFI has to have a Pump Shot Calibration so that it also does not have the hesitation.
Polishing the runners or not putting the wall finish back on the runner walls after porting just screws stuff up, be it EFI or carb.

Hope this helps.

Tom V.

Thanks for the quick reply Tom. That makes sense to me, and after a bit of tuning the EFI the last couple of weeks, which has resulted in a very quick throttle response with almost zero delay, I think I'll leave well enough alone. Hard to see in the one pic I posted, but when I did the port matching I didn't smooth the surface, but tried to leave somewhat of a rough surface. It was surprising just how much material had to be removed when the port matching was done. Was there a reason Holley left them so far off?

[Steve C.]

Much of this now will not deal with the original poster. But a fwiw, the Northwind intake will not fit under a Formula hood. The HSD intake will work there, and at the higher horsepower levels often discussed here the torque loss on a street car might be a moot point with it's use. And even on the track depending on specifics. The dual-plane intake is not always the hot ticket ! Dave Bisshop, and as we have found, has stated the HSD intake can be compettive with a Victor intake if modified, and under certain use.. I have another HSD intake modifed by Dave for use with a 4500 series Dominator carb, and it ran very close with a Victor/ 4500 Dominator carb set up on back-to-back track testing with a combo at the 650+hp level. Hood clerance can be a issue !

Edit: Correction. I should have stated at the 600+ hp level regarding the HSD intake.


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[grivera]

Will an RPM fit under a 1st gen Firebird hood? How about a Torker II?

[Pontiac Derek]

T2 will, rpm is much taller, this is why I port a lot of T2 intakes, we are almost in the 10's with a T2 and 3.08 gears 3800+lbs race weight, TAMAN

[Pontiac Derek]

Absolutely Steve, A ported HSD or Ported T2 is the ticket in many of these situations, i was not shooting you down, just adding info.



QUOTE=Steve C.;5650270]Much of this now will not deal with the original poster. But a fwiw, the Northwind intake will not fit under a Formula hood. The HSD intake will work there, and at the higher horsepower levels often discussed here the torque loss on a street car might be a moot point with it's use. And even on the track depending on specifics. The dual-plane intake is not always the hot ticket ! Dave Bisshop, and as we have found, has stated the HSD intake can be compettive with a Victor intake if modified, and under certain use.. I have another HSD intake modifed by Dave for use with a 4500 series Dominator carb, and it ran very close with a Victor/ 4500 Dominator carb set up on back-to-back track testing with a combo at the 650+hp level. Hood clerance can be a issue !

Edit: Correction. I should have stated at the 600+ hp level regarding the HSD intake.


.[/QUOTE]

[ta man]

Originally Posted by Pontiac Derek

T2 will, rpm is much taller, this is why I port a lot of T2 intakes, we are almost in the 10's with a T2 and 3.08 gears 3800+lbs race weight, TAMAN

No loss of torque with the porting either..the car launches harder!

[grivera]

Originally Posted by Pontiac Derek

http://forums.maxperformanceinc.com/...d.php?t=784792

I meant to comment before- that is some beautiful work you've done there!!

I'm hoping the RPM fits under the 69 bird's hood. Right now the factory intake has a .75" spacer so not sure if that matches an RPM's height.

[Pontiac Derek]

Thank you! I can't tell you how much it measy having anyone here say they like my work!
I'm very Passionate about Engines and everything though there is a million builders out there not many will do an intake like that for under 300$
I know one Porter that Charges 1500$ but is a really good Porter that's for sure!
I pride myself on building/pricing things for the guy that busts his tail to take care of his family!

[Steve C.]

Agree good intake work by a professional is not inexpensive. As mentioned Dave Bischopp years ago did my 'regular' Holley Street Dominator intake. It is a great intake. But he also did another HSD intake with a modified flange to run a 4500 Dominator carburetor. If memory serves me right back then the cost to do the port match, runner blending, and plenium work with the modified flange ran $300.

If interested there is a picture of the intake in post number 38 here:

http://forums.maxperformanceinc.com/...minator&page=2

.

[Pontiac Derek]

There is No Question about it Dave Does Great Work!
But the hours involved all done by hand and not left with a Burr finish I don't think anyone else out there will Fully Port And Sand an Entire Intake That Gains ET and MPH at the track for under 300$
I had to work for everything growing up and I mean Dang near Everything!
I didn't have fancy heads, intakes, roller cams, so I learned My old man, And Many Others, nobody would share anything with me, heck I bugged one Porter so long I thought he was going to call the cops on me lol
Dave at SD gave me a Huge Opportunity to Learn more or less How and what is important on Pontiac Engines, I soaked up Absolutely everything thing I could get my Hands on, he was good to me, let me live in a trailer in front of his house! His Whole Family is Really good People! !!

[Steve C.]

Again mine was done well over 10 years ago for that $300, today I'm sure it would cost more. That and Dave responded here on PY and mentioned he is to busy to consider similar intake work.


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