[BLANK1]

Took the 461 out of my 68 GTO to fix some leaky freeze plugs. Car is roughly at a 3850 lb race weight with a TH400 and 3.73 gears on a 275 drag radial. I bought a new 9.5 inch 4800 converter from Perfect Converter Company. Had a 4000 FTI on it before. Took off my KRE High Port heads and had them shaved to 74cc for a 11.30 CR. They were 80cc and CR was 10.6 before. The heads have a 2.4X1.2 port opening. Other than that they are as they come from KRE. Northwind intake and 1050 Dominator. Current cam is a Jones solid roller 4/7 swap. 316/320 adv. 263/269 @ .050 on a 110 LSA installed at 106 ICL, .421/.412 lobes. Using 1.6 rockers currently. Have a set of 1.72's to try. Lash is .015/.019.
Tried this cam on a 110 ICL and it ran a best 10.97 at 123 mph. Changed to the 106 ICL per Jones advice and it slowed down. Never got close to tens and best of 121 mph. 60 fts got worse too. Usually around 1.6.
The other cam I have is a 307/314, 271/278 @ .050 Lunati solid roller. .418 lobes 108 LSA.
I also had a recommendation for a CompCam solid roller with their High-tech .440 lobes. 296/305, 260/268 @ .050 on a 112 LSA installed on a 112 ICL.
Which cam would be best for my combo? Not sold on the Jones cam just yet but willing to keep it in there. Would probably move ICL to a 108 or 110. Trying to get this thing to at least 10.50 or better. I know its heavy but I don't want to gut it out.

[slowbird]

Honestly best way to get to your goal is send heads to a good head porter. You can probably run all 3 of those cam and not see much more than .15 difference

[Mike Davis]

Bret,
.440 Comp Lobe cams always ran better for me. Comp has a 270/274@.050 on a 110LSA that works really well.
What do the heads flow?

[BLANK1]

Mike,
Don't have any flow numbers. They probably flow whatever a stick HP flows.

[pastry_chef]

Originally Posted by slowbird

Honestly best way to get to your goal is send heads to a good head porter.

Agree.
I'd have head and intake work.

Not sure I've heard of Perfect Converter Company before.

[steve25]

What has the best 60 ft been?
To me the first thing I would do is to get 4.11 gears in the back!

[AG]

Not a recommendation, but an example: the cam I run in my race car is a CC 262/266@0.050", 0.391"/0.399" lobe on a 110 LSA with 1.65 rockers and I run 10.00 at 134 mph at 3550#, 335 cfm heads, Victor/Dominator. You would be about 0.3 s slower with your weight. I can send the cam card if you want.

[Mike Davis]

I don't think a gear change will help. I have run 3.73, 3.90 and 4.10 in my car with absolutely no ET difference. I currently run a 3.90 and that gives the best MPH on my combo.

Bret, head work would pay off. If those are as cast they are suppose to flow around 330CFM. You should be solidly in the 10.50 range with them as they are. I would send the heads off to have them flow around 345-350. I am thinking the port is a little lazy.
We are close to the same weight. My E heads only flow 345CFM.

[Dragncar]

You need to get your 60' figured out first. You need 1.45 60' to even think about 10.50s.
HP from your 60' shows only 444.
HP from MPH shows 576.
Something is wrong, combo all out of whack.
I have 80cc High Ports. Port openings are smaller than yours. Flow over 350cfm just with bowl work.
Several people have flowed as cast HP and they end up in the 315-320 range.
SD Dave told me right from the start these heads are going to want the valve lifted to .750.
I am running just over a .440 lobe on intake.
IMO its all about the 60'. Best ETs always come with the best 60 foots.

[Skip Fix]

My Camaro has 60 ft issues too but is running 10.30s @ 132.5 with mid 1.5s. Heck my smaller 455 in the 78 TA would 60 ft 1.51s weighing more at 3750 but only ran 6.9 1/8s and 10.90 1/4s .

[Dragncar]

What I am trying to say is if he wants 10.50s with only 1.6 60 foots he had better have a whole lot of top end pull that comes on hard.
Un-ported HPs are not going to get it with puny cam and 3.73s along with a converter that is suspect.
The other cars in this thread with E heads that beat the pants off his combo, but they actually flow 335+cfm.

Sends heads and intake to good porter.
Call Lane at PTC and get one.
4.10s
A cam the heads will like more.
10.50s or better.
Combo is miss matched. As it is right now the 1050 could be hurting him. Might run better with the right 4150 carb. None of the numbers I am seeing screams it needs a 1050.
My friend runs 10.62 with home ported 62s 434 in a heavy 2nd gen.
I have low 1.4 60 foots on a good day, average 1.45 with 9-1 junk engine. But the parts work well together. I could hit the tires harder with more power, its not like its on the edge of traction either. More left.
He is 150-200 lbs heavier with far better engine than both of us and should have a lot more power.

[Skip Fix]

Got you. I'm running a 4150. Buddy had a 462 E head roller motor and a SD modified Holley for a Dominator we picked up 60 ft and ET with a 4150.

[ta man]

Originally Posted by Dragncar

You need to get your 60' figured out first. You need 1.45 60' to even think about 10.50s.
HP from your 60' shows only 444.
HP from MPH shows 576.
Something is wrong, combo all out of whack.
I have 80cc High Ports. Port openings are smaller than yours. Flow over 350cfm just with bowl work.
Several people have flowed as cast HP and they end up in the 315-320 range.
SD Dave told me right from the start these heads are going to want the valve lifted to .750.
I am running just over a .440 lobe on intake.
IMO its all about the 60'. Best ETs always come with the best 60 foots.

x2..something is off..I run 126 to 127mph with way way less engine

[Stan Weiss]

Is 3850 with or without you?

What do you have for exhaust?

Have you ever done a cranking compression test?

At what RPM do you shift?

How close is this to your time slip?

60 Foot ET = 1.5848
330 Foot ET = 4.5161
1/8 Mile ET = 7.0031
1/8 Mile MPH = 99.3671
1000 Foot ET = 9.1559
1/4 Mile ET = 10.9929
1/4 Mile MPH = 123.2855

Stan

[BLANK1]

Stan,
This is the best time slip with the Jones cam. This was when it was set at 110 ICL. Its set at 106 ICL now and haven't been able to match this. That weight is with me in it. Has a 3.5 inch x-pipe with Ultra Flow mufflers. Cranking compression was 170-180 in all cylinders. I've shifted at 6000 up to 6500 and it didn't seem to make much difference.

Mike,
I was going to call PTC but then I saw Scott Williams was using a Perfect Converter so I called them and the guy there seemed to know Pontiacs so I ordered a converter from them. They're not to far from me around Cleveland Ohio. I did some research on them first and they seem like a good company that stands behind their product. Nice guy too. He recommended their more pricey 9.5 converter because of the weight of my car and possible use of nitrous. It was $800.

[Skip Fix]

FWIW that time slip looks almost identical to my pump gas 455 in the 78 TA with a Hand convertor 4.11s and 29.5 x9 radial slicks and an UD HFT cam T2. Through a 3" full exhaust. It weighs 3750 with me. You ought t be way faster with your stuff.

[BLANK1]

Skip,
Here's some timeslips with my old 'cleaned up ports' E-heads. These were with the Lunati solid rollers and a 3" exhaust. Everything else pretty much the same on the car.
Don't know why it keeps flipping the photo.
10.8 CR with E heads and 10.63 CR with HP's

[Stan Weiss]

Originally Posted by BLANK1

Stan,
This is the best time slip with the Jones cam. This was when it was set at 110 ICL. Its set at 106 ICL now and haven't been able to match this. That weight is with me in it. Has a 3.5 inch x-pipe with Ultra Flow mufflers. Cranking compression was 170-180 in all cylinders. I've shifted at 6000 up to 6500 and it didn't seem to make much difference.

Mike,
I was going to call PTC but then I saw Scott Williams was using a Perfect Converter so I called them and the guy there seemed to know Pontiacs so I ordered a converter from them. They're not to far from me around Cleveland Ohio. I did some research on them first and they seem like a good company that stands behind their product. Nice guy too. He recommended their more pricey 9.5 converter because of the weight of my car and possible use of nitrous. It was $800.

Since you have engine apart it does really not matter now. But if I had advanced the cam 4 degrees and lost 1.5 to 2 MPH, I would have retarded the cam 2 or 4 degrees (from the 110 ICL) to see what would happen. Also In my opinion if they was not real different in et shifting at 6000 and 6500 I would have looked at other things for example the fuel system.

Stan

[Dragncar]

Its 2017 all over again. Same thread. I was wrong, others were wrong, same place.
Now car is still heavy, but went to a slower port with out doing what it takes, to take advantage of what the the bigger port had to offer.
Better off keeping the E heads and working with them.
I have come to the conclusion that the only advantage the HP head over a good E head applies to a VERY narrow band of racers and about 0% of true street cars.

[PAUL K]

Originally Posted by Dragncar

Its 2017 all over again. Same thread. I was wrong, others were wrong, same place.
Now car is still heavy, but went to a slower port with out doing what it takes, to take advantage of what the the bigger port had to offer.
Better off keeping the E heads and working with them.
I have come to the conclusion that the only advantage the HP head over a good E head applies to a VERY narrow band of racers and about 0% of true street cars.

I believe I have been saying that for years and you told me I'm full of poop.... Glad to see you are learning. That's what these Websites are for.... We did just build one Bad Azz Hi-port stock block engine that made a bunch of power however.