My new TA SI Heads and GN1 Aluminum Heads

Air flow number, back pressure, intake to exhaust ratios and other theoretical data is good stuff, but in the real-world of performance turbo Buicks where the large majority of owners reside, they can easily obtain more HP than needed and seldom used, and proven off-the-shelf performance parts are plentiful to accomplish these goals! :)

With todays technology and 30 years of experience and results, getting 600 RWHP with great reliability is easy to accomplish with a TR, not cheap though.

HP is made with air flow, and the heads is where it happens, the crank, rods and other stuff is along for the ride!
 
The truth will set you free!!

This was a fun project!! It was nice to compare two products side by side. We took some serious weight off the TA's with this process.........and it took more than 5 minutes Brian!!!! I bet we spent an hour or more on each head.

But I'm sure Rick's results will be well worth our effort.

This is the first set of TA's I've looked at and re-worked. So far, I am impressed. I would buy them un-assembled with the valve job done to make the rework faster. I can see even more opportunity to obtain more flow out of the TA heads, but I'd want to verify all changes on a flowbench.

My feedback on the TA's:
  • Overall a Very Nice product
  • Valve bowls should be pocket ported out of the box (nobody would want to use them as shipped)
  • Combustion chamber should be CNC machined out of the box
  • Lot of potential for more flow
  • Overall cost is more than the GN1's
  • A specific set of rocker arms is available that avoid the pushrod interference problems inherent with the GN1's
  • Better Availability than the other alternative
5 minutes on ex bowl went from 140ish to 170+. The full job will take much longer


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Getting 600 RWHP with great reliability is easy to accomplish with a TR, not cheap though.

You can say that two times.

That's about all I have to add to the discussion.



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The TA heads we tested had better exhaust flow than the Champions, but that can be a bad thing when back pressure is high.
Air flow number, back pressure, intake to exhaust ratios and other theoretical data is good stuff, but in the real-world of performance turbo Buicks where the large majority of owners reside, they can easily obtain more HP than needed and seldom used, and proven off-the-shelf performance parts are plentiful to accomplish these goals! :)

With todays technology and 30 years of experience and results, getting 600 RWHP with great reliability is easy to accomplish with a TR, not cheap though.

HP is made with air flow, and the heads is where it happens, the crank, rods and other stuff is along for the ride!
I agree the average owner will never see a performance difference, especially since the average owner most likely has a less than optimum converter, probably not enough valve spring, and a crap tune. But I am about getting the max out of every combo. If you could take a car that ran 10.8, take out a $1000 Vigilante converter, and install a $1000 PTC, and swap the flavor of the week $200 comp beehives out for a set of $100 PAC 1201s, and run 10.3s on the same boost, and easy launch, and ultimately 9.8s with nore boost, then I rhink maxxing out the potential of a combo would make a happy customer. So when I spec a build and someone is ready to drop some serious coin, I am going to spend the $ on the best performing parts for the price, so the customer has a good running car, above the average 11 sec cars with aluminum heads, and every other cool guy part you see out there.
 
The exhaust peak flow wasnt a run away with the TAs, but the overall curve was pretty strong. Either product is good. For all out record setting performance, there are choices to be made. Tom at Champion is a real piece of work, and I will never deal with him personally, but it doesnt stop me from picking up a set of Champions from a private party, or a vendor with integrity.
 
I agree. I think it is just a matter of figuring out how to get that power out of them.

This is hard part in figuring out the combo and one of the reasons l lke to see combos like your Cutlass
The TA heads we tested had better exhaust flow than the Champions, but that can be a bad thing when back pressure is high.

I agree the average owner will never see a performance difference, especially since the average owner most likely has a less than optimum converter, probably not enough valve spring, and a crap tune. But I am about getting the max out of every combo. If you could take a car that ran 10.8, take out a $1000 Vigilante converter, and install a $1000 PTC, and swap the flavor of the week $200 comp beehives out for a set of $100 PAC 1201s, and run 10.3s on the same boost, and easy launch, and ultimately 9.8s with nore boost, then I rhink maxxing out the potential of a combo would make a happy customer. So when I spec a build and someone is ready to drop some serious coin, I am going to spend the $ on the best performing parts for the price, so the customer has a good running car, above the average 11 sec cars with aluminum heads, and every other cool guy part you see out there.

There is not one single part that has as big an impact on a cars performance than the torque converter!!

People will bolt on a set of new heads that flow more and think they will go faster but never bother to look at the cam profile and operating range of the engine in order to see any of the gains they could make with the better heads.

As much as cylinder head flow is important the cam profile is the key piece to making it all work. Having a properly matched cam head and tq converter combo for the power and rpm range you plan to run then selecting a turbo that matches well would seem to me to be the best route to take. Few turbo Buick guys do this, as a matter of fact they typically select a turbo first then match the TQ converter to that then buy some killer heads and select whatever cam and valvesprings are available and pray for the best.

Interestingly enough since I was racing TQ conv tech has come a long way yet I have not seen a lot of new cam profiles or people running anything significantly different than they did 20 years ago? Or maybe they are just keeping it all a big secret IDK?
 
Everybody has a super secret (insert builder here) cam.
I am not running special. I am going to change cams at some point, i think there would be some gain on the intake side.
I get that people want to be different, but I dont understand these people trying to reinvent the wheel with oddball turbos. You spend all of that time on fitting a goofy turbo on the same less than optimum engine combo. The difference between. High 9 sec and 8 sec TSM car isnt the turbo. I would rather spend my time getting the proper components as far as engine amd converter, than having some huge turbo that no one else has. I would rather go faster than everybody with the same thing they are all running.
 
I believe in TSM Richie PSI runs Champion heads and has the record, in TSO Gomes, Fiscus and Manny use to run Champion heads. Question is if these racers ran them, why would they not run the TA and go faster as stated the TA outflow the GN1?

Ron
 
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Fiscus Gomes and Manny are all S2 head cars. Just because someone is competing at a high level with certain parts doesn't always mean they are the best parts available and that is why they chose them.
 
A lot of what I have been discussing on this thread Manny has been posting about in the cylinder head madness thread he started. Very good read and info there.
 
This is not meant to be a good vs bad comparison between TA Performance SI heads and GN1 Aluminum heads. This is simply an “Out of the Box” look at what your money buys. It should be noted that both sets of heads were purchased un-ported.

The new GN1 heads were at Dave’s shop for another engine build when we started the clean-up work on my TA SI heads. When I say we, I mean Dave. During my work on the TA heads, I documented some visual differences between the two different cylinder heads.

Visually, the TA heads appear to have the pushrod holes machined to tighter tolerances and have slighted larger intake valves. The GN1 head as received have a much smaller lip (almost none) in the valve bowl area under the valve seat. The TA heads have a significant lip in the valve bowl area under the valve seat. My goal on this project was to eliminate this lip on the TA head and improve the airflow

Another difference noticed which may or may not be significant was a difference in the combustion chamber finish. The TA SI heads have an “As Cast” finish. The GN1 heads have a fully CNC’d combustion chamber. You will see this and other differences on the attached slides.

I am very pleased how the TA heads turned out and I plan on putting them on the car in August.


Updated with missing pictures...
 

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