i know im really swaying here....but heads maybe

[nmcgrawj]

Not so fast.

Cam timing changes the car's powerband, not the intake manifold. He won't need anymore gear either - a 4.10 is plenty. Jay is probably going to tell him he'll need bigger headers too. According to your theory, he'll lose even more low end? I doubt it...

Email Jay. I'm interested in what he'll say now....

Joe

I've been there with Jay. Holley is at the top of the list of long runner intakes for size really. The TFS-R and Vic Jr. are in a league of their own and starting to get into short runner lengths which gives upper RPM power. The Stock Holley takes away a little down low, but it rips apart all the other long runner style intakes up top.

The TFS-R and Vic-Jr will take away even more down low power then the holley would. Will they make it up on the top end? Sure. But he shot down the idea of it being a 1/4 car really quick. He sounds like he would like a killercanary type of car who loves that low end power up till about 6000 for his daily driver. Nothing is wrong with that. Its just a matter of taste. The Cam timing does infact control where power is...but thats to a certain extent. With stuff in the same neighborhood the cam can make up for it...but once you start to get stroker type of stuff....you are gonna sacrifice somewhere because of the lack of cubes.

If he is sticking with a stock 302 shortblock, then he is going to need a nice amount of gear. I wont have those huge heads or huge intake like that and Jay wants me to get a 4.30. Thats ofcourse as long as i hook up and i will have a 2.94 1st gear in my T-5. A 4.10 will be easier to hook up, but once i get my suspension tied, i want what will give me the best outcome. A 4.10 will work, shoot a 3.73 will probably work....will it work best? Who knows.

Now please, im not setting anything in stone. Im 19. Im trying to learn all the true facts from the Pro's that know this stuff. So im just trying to relate what i have picked up from my conversations with Jay. I could be wayyy off but its all good....im willing to be wrong and to learn the right things

 

[Joes95GT]

Holley is at the top of the list of long runner intakes for size really. The Stock Holley takes away a little down low, but it rips apart all the other long runner style intakes up top.

Agreed. I don't think that the Holley in it's stock form will keep up with the cylinder heads, hence the reason I suggested a ported Holley. Now, I didn't say port it until you start to cut holes in it. Maybe just straighten up the runners a bit...

The TFS-R and Vic-Jr will take away even more down low power then the holley would.

I don't know that I would group the TFS-R in the "short runner" catergory. In my previous post, the reason I said "maybe" and I do emphasize "maybe" a Vic. Jr would work, but I doubt it.

The Cam timing does infact control where power is...but thats to a certain extent. With stuff in the same neighborhood the cam can make up for it...but once you start to get stroker type of stuff....you are gonna sacrifice somewhere because of the lack of cubes.

I wouldn't go that far.

Cam timing controls the motor. Now, we aren't talking about cams with 290 degrees of duration @ 0.050 and 1.250" lift. I'm talking about the regular 215-230 degrees @ 0.050 street cams. With a long runner manifold, and late cam timing, the engine is going to have a suction-like vacuum-effect in the cylinder. Think of it this way...

The piston is coming up to TDC between the exhaust and intake strokes. Both valves are closed. The piston passes TDC and is headed down towards BDC on the intake stroke. Both valves are still closed, but now you have the piston pulling against what? NOTHING! When that intake valve cracks, it's going to pull an ENORMOUS amount of air in because that piston is acting like a suction. The long runner manifold helps aide this suction-affect. The same would be harder to achieve with a "shorter-runner" Vic. Jr. manifold.

Now, because the cam is going to be grinded on a wide LSA (this is almost a given), and the valve events are so late, the intake and exhaust duration are going to have to be quick to keep the LSA. What happens when cam timing has to be sped up? Duration @ 0.050 goes down. When duration at 0.050 goes down, the only way to keep the lobe area the same is to add LIFT. This cam will probably have .600"+ lift figures.

If he is sticking with a stock 302 shortblock, then he is going to need a nice amount of gear. I wont have those huge heads or huge intake like that and Jay wants me to get a 4.30. Thats ofcourse as long as i hook up and i will have a 2.94 1st gear in my T-5. A 4.10 will be easier to hook up, but once i get my suspension tied, i want what will give me the best outcome. A 4.10 will work, shoot a 3.73 will probably work....will it work best? Who knows.

A 4.10 is plenty. Especially for a street car. Aren't you doing a 351? That's probably why you need a bit more gear.

Now please, im not setting anything in stone.....im willing to be wrong and to learn the right things

Me neither. Me too.

Joe

 

[nmcgrawj]

Agreed. I don't think that the Holley in it's stock form will keep up with the cylinder heads, hence the reason I suggested a ported Holley. Now, I didn't say port it until you start to cut holes in it. Maybe just straighten up the runners a bit...I don't know that I would group the TFS-R in the "short runner" catergory. In my previous post, the reason I said "maybe" and I do emphasize "maybe" a Vic. Jr would work, but I doubt it.I wouldn't go that far.

Agreed

Cam timing controls the motor. Now, we aren't talking about cams with 290 degrees of duration @ 0.050 and 1.250" lift. I'm talking about the regular 215-230 degrees @ 0.050 street cams. With a long runner manifold, and late cam timing, the engine is going to have a suction-like vacuum-effect in the cylinder. Think of it this way...

The piston is coming up to TDC between the exhaust and intake strokes. Both valves are closed. The piston passes TDC and is headed down towards BDC on the intake stroke. Both valves are still closed, but now you have the piston pulling against what? NOTHING! When that intake valve cracks, it's going to pull an ENORMOUS amount of air in because that piston is acting like a suction. The long runner manifold helps aide this suction-affect. The same would be harder to achieve with a "shorter-runner" Vic. Jr. manifold.

Now, because the cam is going to be grinded on a wide LSA (this is almost a given), and the valve events are so late, the intake and exhaust duration are going to have to be quick to keep the LSA. What happens when cam timing has to be sped up? Duration @ 0.050 goes down. When duration at 0.050 goes down, the only way to keep the lobe area the same is to add LIFT. This cam will probably have .600"+ lift figures.A 4.10 is plenty. Especially for a street car. Aren't you doing a 351? That's probably why you need a bit more gear.Me neither. Me too.

Joe

You know...i thought the piston going down caused the suction affect too which brought in the air from the intake...after having lunch with Jay Allen, he explained that it is actually the exhaust collector where all the gases merge, thus the exhaust leaving causing a vacancy in the cylinder providing for the low pressure which sucks in the air charge. He said the air charge starts at the exhaust header and ofcourse the piston going down takes over but it all starts in the exhaust.

Im not sure what you consider a wide LSA, is 112 wide? Just asking, no real reason.

I was going to do a 351...but funds wont allow it. Thats going to have to wait until i graduate. This is going to be your average(well not so average according to the usual h/c/i on here) h/c/i rebuild on a stock shortblock. So its going to have the 4.30 gear in the back. I have a feeling that with a 351 you would need or want less gear cause of the torque you would have.

I cant wait till next spring to get it together. Traction will be an issue obviously until i get some more money for the rear end and suspension. But it should run like no other with Jay's cam runnin the show.

 

[nmcgrawj]

Agreed. I don't think that the Holley in it's stock form will keep up with the cylinder heads, hence the reason I suggested a ported Holley. Now, I didn't say port it until you start to cut holes in it. Maybe just straighten up the runners a bit...I don't know that I would group the TFS-R in the "short runner" catergory. In my previous post, the reason I said "maybe" and I do emphasize "maybe" a Vic. Jr would work, but I doubt it.I wouldn't go that far.

Agreed

Cam timing controls the motor. Now, we aren't talking about cams with 290 degrees of duration @ 0.050 and 1.250" lift. I'm talking about the regular 215-230 degrees @ 0.050 street cams. With a long runner manifold, and late cam timing, the engine is going to have a suction-like vacuum-effect in the cylinder. Think of it this way...

The piston is coming up to TDC between the exhaust and intake strokes. Both valves are closed. The piston passes TDC and is headed down towards BDC on the intake stroke. Both valves are still closed, but now you have the piston pulling against what? NOTHING! When that intake valve cracks, it's going to pull an ENORMOUS amount of air in because that piston is acting like a suction. The long runner manifold helps aide this suction-affect. The same would be harder to achieve with a "shorter-runner" Vic. Jr. manifold.

Now, because the cam is going to be grinded on a wide LSA (this is almost a given), and the valve events are so late, the intake and exhaust duration are going to have to be quick to keep the LSA. What happens when cam timing has to be sped up? Duration @ 0.050 goes down. When duration at 0.050 goes down, the only way to keep the lobe area the same is to add LIFT. This cam will probably have .600"+ lift figures.A 4.10 is plenty. Especially for a street car. Aren't you doing a 351? That's probably why you need a bit more gear.Me neither. Me too.

Joe

You know...i thought the piston going down caused the suction affect too which brought in the air from the intake...after having lunch with Jay Allen, he explained that it is actually the exhaust collector where all the gases merge, thus the exhaust leaving causing a vacancy in the cylinder providing for the low pressure which sucks in the air charge. He said the air charge starts at the exhaust header and ofcourse the piston going down takes over but it all starts in the exhaust.

Im not sure what you consider a wide LSA, is 112 wide? Just asking, no real reason.

I was going to do a 351...but funds wont allow it. Thats going to have to wait until i graduate. This is going to be your average(well not so average according to the usual h/c/i on here) h/c/i rebuild on a stock shortblock. So its going to have the 4.30 gear in the back. I have a feeling that with a 351 you would need or want less gear cause of the torque you would have.

I cant wait till next spring to get it together. Traction will be an issue obviously until i get some more money for the rear end and suspension. But it should run like no other with Jay's cam runnin the show.

 

[Joes95GT]

You know...i thought the piston going down caused the suction affect too which brought in the air from the intake...after having lunch with Jay Allen, he explained that it is actually the exhaust collector where all the gases merge, thus the exhaust leaving causing a vacancy in the cylinder providing for the low pressure which sucks in the air charge. He said the air charge starts at the exhaust header and ofcourse the piston going down takes over but it all starts in the exhaust.

Now we're talkin....

Yes, you're right. It starts in the collecter. However, the piston does the doing in conjunction with the camshaft. Big headers help achieve the affect you speak of. With small headers, it would seem that back pressure will build up and not cause such great differences in pressure. It's all in the combination of parts not one specific part.

Im not sure what you consider a wide LSA, is 112 wide? Just asking, no real reason.

I would say anything greater than 112 is "wide". I like wide LSA cams.

I cant wait till next spring to get it together. Traction will be an issue obviously until i get some more money for the rear end and suspension. But it should run like no other with Jay's cam runnin the show.

I wish you luck with the combo. As always, I'll be here to try and fill in the blank spots.

Joe

 

[nmcgrawj]

I wish you luck with the combo. As always, I'll be here to try and fill in the blank spots.

Joe

Thanks man, good discussion!

Now, to the original post, email Jay Allen or Ed Curtis and see what they say. From experience, i think Ed curtis will think its too big, he is known for small heads and intakes for motors with A LOT of torque. But still email him, cause i dont know him well enough to tell you not to. Or email Jay. I know he will be able to come up with something for your combo. He cost a tad bit more but its worth it IMO

 

[HazMat404]

well im pickin these heads up for $600 next week. ill be slowly collectin parts for next spring when it all goes in. i will talk to a few different cam guys and see what they suggest in terms of different intake and what kinda cam ill be lookin at too. i appreciate the help all of you. thanx