[Targa]

I have been looking around for a nice/decent set of Alum. heads for my 520 IA2 turbo setup and nobody seems to have anything available here, or at PZ or ebay so I started poking around tonight at buying new heads.

When I saw Doc's T/A many, MANY months ago when he started his turbo build, I liked those heads with the Cov. exhaust option.

Now, I am building a 2nd gen. turbo bird as well so the Cov. exhaust option just seemed right due to space limitations.

Anyway, since nobody has any used heads out there I just tonight checked out the cost of a new set and its pricing is ok.

Or does someone know where to get the best price??? Please PM me if there is an option.


So... The only real issue I see is there seems to be some kind of speculation about the rockers you can choose to use.

Some say you can use the Yella Terra YT6317 rockers. But these are BBC rockers and I have seen where guys are saying you can not use a BBC rocker (different brand though) cause they dont just fit out of the box.

You 'might' be able to make them fit, they claim??
But can you?
If so, how?
If not why do the YT rockers fit?

I have searched for 2 hours now and simply can not find a straight answer on the net anywhere. Here or PZ or YB or abroad..??

I do see that T&D make a set that fits (so I have read) but I think guys are saying they are 400+ bucks more than the YT set?

I dunno.... anyone care to explain why one BBC rockers set will work and the next wont? And... why>?

Can the YT set work?

I do not want to pay more for the T&D set if in fact I can get a lower cost set to do the same work. Not a race car here. Just 1000hp fun street car...lmao.

Is there anything else anyone has to offer as far as something to look out for? Check on?

Push rod dia. limitations/issues?


TIA for any info guys.... it is appreciated.

[mysticmissle]

I run harland sharpes on mine. no girdle no problems. sharpe says they are good to 1'' of lift and 800#s i believe. dont know if id trust that but so far so good. I was going to run YTs but after waiting on back order for 6 months and not breaking a standard rocker in the meant time I am riding these out. As far as any BBC rocker fitting, its the width across the trunion that needs to be considered. if they are not too wide there any should be useable.
.080 3/8 push rods should be fine for what you are talking. mine are manley tall deck BBC lengths. you WILL have to clearance IA block to use 3/8+. no big deal just do it first!

[500plus]

I run the H/S rockers as well with 3/8 pushrods turn to 7k all the time with no valve train re-adjustments been needed. IMO they work just fine.

[bruce driggers]

I have been using the yella terras for two seaons without any issues , made over 150 passes leaving at 5600 & shifting at 7000 ,

[T Syron]

Originally Posted by Targa

Anyway, since nobody has any used heads out there I just tonight checked out the cost of a new set and its pricing is ok.
Or does someone know where to get the best price??? Please PM me if there is an option.
.

Contact Calvin @ Hill Performance. Do a search in the race section for Calvin Hill, he has what you are looking for.

[BADDTA]

Originally Posted by T Syron

Contact Calvin @ Hill Performance. Do a search in the race section for Calvin Hill, he has what you are looking for.

Ditto. Calvin's the man!

[goquick]

You can use the bbc rockers! Comp, Harland Sharp, Yella Terra, Comp Pro Magnums, take your choice. You can take your choice from inexpensive roller rockers to shaft rockers.

[R 70 Judge]

Originally Posted by Targa

I have been looking around for a nice/decent set of Alum. heads for my 520 IA2 turbo setup and nobody seems to have anything available here, or at PZ or ebay so I started poking around tonight at buying new heads.

These were in the for sale section. Sounds like a really nice set of heads that were done by a reputable head porter (Barton). The price is pretty fair as well.

http://forums.maxperformanceinc.com/...ghlight=tunnel

[David Holmberg]

Originally Posted by R 70 Judge

These were in the for sale section. Sounds like a really nice set of heads that were done by a reputable head porter (Barton). The price is pretty fair as well.

http://forums.maxperformanceinc.com/...ghlight=tunnel

That's a great deal, but the chambers are probably too small for a turbo.

[johnta1]

Don't look like CV-1 heads?

[bankbook]

Let me tell you through my experience.

1. Pricing best head for the dollar. Meaning, the head is ready to go, when you get it without any modification needed elsewhere.

2. Performance- no one can touch the flow they make out of the box.

3.Customer service-Better than most I have ever dealt with before,during, and after the sale.

4. Convertible exhaust feature- makes life much easier when trying to fab up headers. It also makes installation and header removal if needed a snap.

5. Rockers- They were designed for BB Cheby to give a wide range of choices and to keep costs down. Do you need the shafts, no and if I had to do again I probably would have saved the money. Everyone running the rolleres are spinning to 7000 rpm with no issues to date.

Pushrod issues- On mine I had to clearance the diameter of the holes for the larger pushrods. No big deal.

Overall my rating on the head stands at an A+

You will easily have a 1000hp plus engine with that size engine and these heads the way that they flow. I Know.

[mysticmissle]

i happen to have my valve covers off today so i took some pics for you. there is about .125 between the intake rockers. these were 1.7 HS. measure just a tad less than 1.600

[bankbook]

Well if we are going to show pictures, heres mine!

[mysticmissle]

i like yours better!

[goquick]

Bankbook, very nice pictures of the convertible exhaust option

[twinturrbo406]

Originally Posted by bankbook

Well if we are going to show pictures, heres mine!

..... hummm, where have i seen those heads before ???

[ponjohn]

Can you use the convertible exhaust N/A?

[BruceWilkie]

Originally Posted by ponjohn

Can you use the convertible exhaust N/A?

Yes. If you have a tube chassis car or tight fit situation it might be a solution. With the "droopsnoots" missing and provided you have room a straight shot out the port for several inches can help exhaust flow. Helps take some of the heat load off that lower center head bolt/stud also.

However std round port headers work fine for most apps.

CV1 head is a VERY high quality casting and very strong where it needs to be(like rocker stud stands, deck and bolt holes).

IIRC Mystic has seen near 7800 rpm a few times without issue. fwiw Scorpion also makes a VERY good rocker. The 528 Ford I built, I used Scorpion and with Manley Nextec springs and .767 NET lift I saw no change over my checking springs when I checked it. Plenty of spring clearance as well and lifetime gaurantee.

BTW Calvins CV1 Quest and Fusion heads share the same flow improvements to the std ex port and both ex ports are the same port when he's done with them. VERY nice and ex flow is quite an improvement at nearly 300 cfm.(295) The intake ports of both the Quest and Fusion flow well over 400cfm and pretty much same flows. The Quest port is based off the std casting, the Fusion is based off the porters head. Fusion is a smaller port with higher velocities than the Quest. Quest is still acceptable velocities though and on a supercharged/turbo/n20 motor might be the better choice IMO as those type motors seem to like a little extra volume. I got to see the testing of the Quest port at Mondellos and its real smooth with no dips through the lift curve. Showed no signs of wanting to stall either. Was still gaining and smooth at 1" lift! NO trick valve job either! Impressive.

Give Calvin a call if you have questions, straight up honest about what he thinks will be best. 708-250-7420

Oh I did a little math and the CV1 Quest heads could support about 1075 hp at 10 psi boost NO intercooler with the right turbo(s) (cam choice, tune etc). Around 1500+ at 15 psi non intercooled And intercooled 15 psi probably near 1800 HP. Real world safe reasonable tune not fully sorted(cam, intake, ignition, exhaust, fuel etc.) knock 10-20% off those numbers.

A std as cast CV1 head should be able to support 950 -1000 hp at 10 psi and about 1120hp at 15 psi non intercooled.(turbo'd)

Choosing the right turbo(s) is the key to make these numbers happen.

If belt driven centrifugal knock another 10-15% off for belt drive losses.

[goquick]

Originally Posted by ponjohn

Can you use the convertible exhaust N/A?

YES ! It's an improvement over the normal Pontiac exhaust. Everyone that has used this option has went quicker.

[Tom Vaught]

Originally Posted by bankbook

Well if we are going to show pictures, heres mine!

I always thought that the "Convertible Exhaust Flange" was one of the best features of the CV-1 heads, especially with plumbing a turbo system.

Tom Vaught