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hi everyone or anyone I own a 75 nova and im doing the top end got some tfs heads gen 1 heard bad things about the geometry like you have to have special rockers from comp but I got some nice Harland sharp rollers hoping they will work? also im looking for some one who has fabricated their own guideplates for these maybe share some info on how you have done yours as trick flow doesn't sell them anymore and customer service is the worst ive ever seen hahaha oh and its too late to back out of these heads too much invested already if there is a way I will make it work thanks in advance
 

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tfs heads gen 1 heard bad things about the geometry like you have to have special rockers from comp but I got some nice Harland sharp rollers hoping they will work? also im looking for some one who has fabricated their own guideplates for these maybe share some info on how you have done yours as trick flow doesn't sell them anymore and customer service is the worst ive ever seen hahaha oh and its too late to back out of these heads too much invested already if there is a way I will make it work thanks in advance
Here is an old 09 post from Mr. Nova. Hope it helps. Jack

Here are the specs for the "as delivered from TFS" for both versions:

G1 TW:
180cc intake port volume
64cc chambers
2.02"/1.60" valves
13* intake / 23* exhaust valve angles
Cast iron or manganese bronze valve guides
1.250" valvesprings (110lbs / 290lbs open, .500" max lift capable)
7* locks / retainers
3/8" GM Corvette rocker studs

Flowdata:
Lift----Intake----Exhaust
100----66--------52
200----143-------110
300----187-------148
400----223-------178
500----232-------194
600----240-------204

1204 Fel-Pro radius inlet
4.030" bore sleeve / mounting plate
28" test pressure
1 3/4" x 4" pipe on exhaust
Superflow SF-600 flowbench

The G1 head is capable of supporting 475-500hp right out of the box, with no porting.

G2 TW:
190cc intake port volume
67cc chambers
2.02"/1.60" valves
16* intake / 18* exhaust valve angles
Angled spark plugs
Powderd metal valveguides
1.470" diameter valve springs (110lbs seat / 305lbs open, .540" lift capable)
7* locks /retainers
3/8" ARP rocker studs

Flowdata:
Lift----Intake----Exhaust
100----68--------53
200----144-------106
300----206-------144
400----242-------173
500----252-------195
600----257-------205

1204 Fel-Pro radius inlet
4.030" bore sleeve / mounting plate
28" test pressure
1 3/4" x 4" pipe on exhaust
Superflow SF-600 flowbench

The G2 heads are capable of supporting in excess of 500hp right out of the box with no porting whatsoever.

The "rule of thumb" for maximum camshaft specs on either version of the TW design are as follows (For flat top & dish piston applications only):

No more than 236* @ .050" duration, no less than 108* LSA, you can go upwards of .525"-ish lift before you get into any real PtoV issues.

As with anything, there will be some amount of flexibility in regards to cam profiles as duration @ .050", LSA & ICL can all be adjusted to allow for higher lift values on an unmodified, stock valve relief piston.

If you wanted to use a dome piston, then yes, you will definitely be purchasing a set of custom pistons.

The TW design works great, you will not be disappointed in the performance of those heads.

By the way, it appears as if he has Harland Sharp rockers mounted on the heads, Those rockers (along with Proform, Crane "Energizer" & all of the various "off shore" rocker arms...) are not recommended for either version of the TW heads.You would want to use a Crane "Gold", Comp "Pro Magnum" or, of course, the TFS rockers...

The spring pockets on all to the TW heads have a spring seat bore that is 1.610" OD. Crower makes a couple of ID locators that fit the .500" OD valveguide and allows for up to a 1.550" OD spring.

68938-16 = 1.560" OD, .740" OD shoulder, .505" ID.
68929-16 = 1.565" OD, .660" OD shoulder, .505" ID.

The only real limiting factor on the G1 head is the fact it uses a 4.450" OAL intake valve & a 4.750" OAL exhaust valve. As you guys already know, a factory GM valve is 4.910" OAL. With the shorter valve lengths you are limited to approximately 1.830"-1.850" installed height. There are no options for longer or larger diameter valves (unless you go with custom valves..$$).

Most solid roller camshafts will require springs that install @ 1.900" & taller.

While a 4.910" valve is readily available, it is also approximately .450" longer than the 4.450" intake valve that head uses. You are not going to install a +.450" length valve in the G1 head without relocating the intake rocker stud.

On the exhaust side, you are looking at a difference of approximately .160", not nearly as big of a deal when compared to what the intake side will need to get it workable.

The G2 head is a different story altogether as it uses + .050" valves right out of the box, so getting longer valves & taller installed height in the G2 is pretty straight forward.
 

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Discussion Starter #3
thanks jackel

thanks jackel some very useful information I actually just order the 8 roller rockers from comp cams part #1607-8 I do believe.... going to use my Harland sharps for the exhaust side and try to sell the other 8 which really sucks but whatever. now if I could just find some guide plates I would be in business my dad says we can cut and weld but that scares me a tad bit crazy no other company has made these seems like they would sell a ton as no one can find them
 

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If I could just find some guide plates I would be in business my dad says we can cut and weld but that scares me a tad bit crazy no other company has made these seems like they would sell a ton as no one can find them
Will a adjustable guide plate work for the Trick Flow Gen 1 Heads? Comp has some that may work. Jack
 

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AFRs are an adjustable guideplate also.
 
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