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Trick Flow® GenX® 255 Cylinder Heads for GM LS3 TFS-3261T002-C01

Cylinder Head, GenX® 255, CNC Comp Port, Assembled, 69cc CNC Chamber, 448 Lb. Springs, Ti Retain, GM LSX, Each

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  • Order this item and get free delivery and handling on your entire order! Offer excludes truck freight and oversize fees. Valid on orders shipped in the contiguous United States.

Hazardous Material Warning
WARNING: Cancer and Reproductive Harm For more information, visit

Brand: Trick Flow Specialties

Manufacturer's Part Number: TFS-3261T002-C01

Part Type: Cylinder Heads

Product Line: Trick Flow® GenX® 255 Cylinder Heads for GM LS3

Summit Racing Part Number: TFS-3261T002-C01

UPC: 842645109010

Cylinder Head Style: Assembled

Cylinder Head Material: Aluminum

Intake Port Shape: Rectangular

Intake Valve Diameter (in): 2.165 in.

Cylinder Head Finish: Natural

Combustion Chamber Volume (cc): 69

CNC-Machined Combustion Chamber: Yes

Intake Runner Volume (cc): 255cc

Exhaust Runner Volume (cc): 87cc

CNC-Machined Intake Runner: Yes

CNC-Machined Exhaust Runner: Yes

Combustion Chamber Style: Heart

Intake Port Location: Standard

Exhaust Port Shape: Oval

Exhaust Port Location: Standard

Spark Plug Style: Angle

Intake Valves Included: Yes

Exhaust Valves Included: Yes

Exhaust Valve Diameter (in): 1.600 in.

Valve Springs Included: Yes

Maximum Valve Lift (in): 0.650 in.

Outside Diameter of Outer Spring (in): 1.300 in.

Damper Spring Included: No

Number of Springs Per Valve: Dual

Retainers Included: Yes

Retainer Material: Titanium

Locks Included: Yes

Lock Style: 7 degree

Valve Stem Seals Included: Yes

Rocker Arm Studs Included: No

Rocker Arms Included: No

Rocker Arm Nuts Included: No

Guideplates Included: No

Accessory Bolt Holes Drilled: Yes

Intake Valve Angle: 12

Exhaust Valve Angle: 12

Valve Guides Included: Yes

Valve Guide Material: Powdered metal

Valve Seats Machined: Yes

Valve Seat Machine Style: 3-angle

Valve Seat Material: Ductile iron

Steam Holes Drilled: No

Oiling Style: Through pushrod

Machined for O-Ring: No

Heat Crossover: No

Quantity: Sold individually.

Notes: These cylinder heads can only be used with a minimum bore diameter of 4.000 in. Includes new rocker arm rail mounts for use with LS3 1.7 ratio rocker arms. OEM rocker arm rail mounts will not work with these heads.

CARB EO Number: D-747-1 (pdf)
To see a list of qualifying vehicles, enter CARB EO Number D-747-1

Emissions: California EO Approved

In-Store Pickup: Choose In-store pick-up (OH, NV, GA, TX) on our web site.

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Trick Flow engineers used the best features of OEM GM LS3 and LS7 cylinder heads, combined with their own race-winning engineering and technology, to create the GenX® 255—the ultimate ultimate square port LS cylinder head for 4.000" and larger bore engines. The heads feature fully CNC Competition Ported runners with a premium high resolution surface finish for maximum airflow and performance potential. Stock LS3 ports accommodate LS3-style intake manifolds and LS9/LSA blower assemblies. The valve angles have been changed from 15° to 12° to increase piston-to-valve clearance and allow the use of larger camshafts. The coolant holes through the head deck were redesigned to work with all LS head gasket and engine block combinations. GenX 255 heads are available with standard or 6-bolt per cylinder mounting patterns.

Trick Flow GenX 255 cylinder heads are emissions-legal under CARB E.O. #D-747 for 2007-present GM vehicles with 6.2L engines. They are available fully assembled or as bare castings. Sold individually.


Questions & Answers Ask a Product Question

I'm not seeing Intake valve size -can that be provided in the specs? I see exhaust valve size, etc, but not the intake valve size. Thanks

Asked by MARTIN on December 24, 2017


Oops -I was overlooking the first couple lines... my bad.

MARTIN from MN answered on December 24, 2017

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Will this fit a 2014 l99? If so how much power would I gain off of this?

Asked by JUAN on August 31, 2017


Thank you for your question. Much of that will depend on your camshaft. If you do a VVT and AFM delete, a cam as large as the TFS-32603001 can be used without piston to valve clearance issues.

You would need always confirm piston to valve, but the TFS-255 heads have .040 more piston to valve clearance than a stock head has for comparison.

This combination is similar to their stage 3 top end kit which produces 583 horsepower at the crank. This would equate to a little over 500 to the wheels depending on the vehicle/exhaust system/tune. That cam does tune well in the hands of a qualified tuner...not too choppy or surge at cruise.

The graph can be seen by copying and pasting the link into your browser:

Summit RacingSummit Racing Answer - August 31, 2017

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Will these fit a 2015 l99 camaro? What cam would be recommended? Should it be done with a ls3 conversion? What kind of power would I get with just heads on stock l99 with a tune after install?

Asked by JAMES on June 11, 2017


These heads have exceptional flow characteristics for the LS3. The L 99 has an active fuel management and a variable cam timing set up and GM has done their best on this particular model to enhance the engine performance as well as fuel economy by adding these features. That said, the LS3 has about 430 hp and the L 99 is about 400 horsepower Although I believe the trick flow heads have an exceptional flow characteristic as well but if I was going to change The heads and cam for increased horsepower yes I believe these would greatly improve your flow I don't know whether it would be worth it unless ( if the car were mine) I was looking at a "boosted" application and all out performance meaning, changing heads, cam, adding headers, New intake with 102 mm throttlebody or supercharger and larger injectors . Otherwise I don't know that it would be worth it because alleviating the active fuel management systems and variable timing and adding all these other components except for the supercharger will only gain you maybe 200 hp at A pretty high cost. My system is a iron block 6.0L bored .030 stroked 4 inches for a 408 cu. in it has the trick flow heads and the 625 track cam and will produce about 600 hp at the crankshaft. The thing is I added all this stuff plus a forged K-1 rotating system and got about 10.4:1 compression and your engine is producing that now bone stock. Finally, I don't know whether this answer your question but simply put yes these heads/cam will increase your flow and horsepower by how much I'm not absolutely sure (150-200hp) but to take advantage of higher horsepower you need to add more fuel which means intake and injector changes plus bigger exhaust to make it Breathe. I guess it depends on how much money you want to spend and what your final expectations for horsepower is? I would pick what kind of horsepower I want at least 200 to 300 more than your engines production now and then build it.

STEPHEN from IN answered on August 03, 2017

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Is this price for a set of heads?

Asked by LEE on July 26, 2017


I wish!! Unfortunately that price is for one head.

KYLE from Canada answered on August 12, 2017

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+See All Questions (6)

Most Helpful Reviews Review This Product

2 Customer Reviews for Trick Flow Specialties TFS-3261T002-C01 - Trick Flow® GenX® 255 Cylinder Heads for GM LS3

Average Customer Review

5 Star


4 Star


3 Star


2 Star


1 Star


+See All 2 Reviews

Great product at an affordable price.

Summit RacingSummit Racing Verified Purchase

As I've already stated. The gen x heads are a great product. I'd recommend them to anyone building a ls engine with at least a 4 inch bore. As for summit racing equipment. Here I'm not so satisfied. In the past year I've spent thousands at summit racing and if memory serves me. I've received I think 20 summit bucks. Not only this, I got the run around on a pair of g force axles that wasn't right. Three weeks of him hawing around and they push me off on the manufacturer. They still aren't right. more

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Reviewer: from KS

Date: January 11, 2018


Summit RacingSummit Racing Verified Purchase

Excellent simply the best enormous power!!!!

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Reviewer: from Kuwait

Date: December 24, 2015

Ease of Installation

Some parts are not legal for use in California or other states with similar laws / regulations

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