My 3.5 Semi-Hybrid Swap... Progress and Information NO 56K - Page 7

*Dv8* · 03-01-07, 03:07 AM

Quote:

Originally Posted by sr5guy

Yessir he used a Rl Manifold with type II heads.

The benefit of using the 3.5 heads is that the intake manifold does not have to be widened. I was really amped when I found out that the Type II manifold bolted right up to the 3.5 block/heads.

-Matt

Come on now Matt, also tell the people what the benefit is by using the TYPE II heads on a 3.5......

Ive got my TYPE II man right here and am going to install it within the next few months and compare.

~Dv8

sr5guy · 03-01-07, 03:32 AM

Quote:

Originally Posted by Dv8

Come on now Matt, also tell the people what the benefit is by using the TYPE II heads on a 3.5......

Ive got my TYPE II man right here and am going to install it within the next few months and compare.

~Dv8

There are 2 main benefits that are had with the type II heads that cannot be retrofitted to the RL head without significant expense:
1. The intake valve is 1mm bigger than the type I or RL.
2. The type II (and type I) valve train is more robust. There are extra mounting points on the rocker assembly. This probably is one of the reasons for the RL's low red line (6000rpm?)

There are 2 more benefits that are had with the type II head that CAN be retrofitted into the RL head:
1. Type II camshafts with slighly longer duration and different timing/lift.
2. Stiffer valve springs.

That being said... There are a few questions that havent been answered yet.

Is the 1mm larger valve worth all the work required to do this?
What is the RPM limit for the RL's drivetrain?
Mike Diaz, What RPM limit are you running on a daily basis with the RL heads?

My theory is that its not worth the extra work and expense, therefore I am going to eventually retrofit the RL heads with the type II cams and valve springs.

There is also another problem with using the type II heads, and DV8 I think you can most benefit from this. because of the different deck heights the cam centerline is offset. I think this could be solved with Buzzards cam wheels. I'm not an engine builder and I wouldn't even know how to get cams back into centerline, but I know it has to be done.

Also, and this is more of a question than anything. The 3.5 is a "stroker" motor. Doesn't this mean that high RPM performance is somewhat limited no matter what you do?

-Matt

*Dv8* · 03-01-07, 06:51 AM

Wasnt that expensive to have the manifold widened and im sure an adapter plate could be made. An argument can be made eitherway. With the webcams the 3.5 engine continues to make power past 7k no problem. My shift light is set at 7 and shift there everytime i drive the car.

I remember Kenso and I discussing this a while back, and he had mentioned that the cams are located in the exact same centerline on both heads and that the additional height came from above.
Your not talking about degreeing the cams are you?

~Dv8

Quote:

Originally Posted by sr5guy

There are 2 main benefits that are had with the type II heads that cannot be retrofitted to the RL head without significant expense:
1. The intake valve is 1mm bigger than the type I or RL.
2. The type II (and type I) valve train is more robust. There are extra mounting points on the rocker assembly. This probably is one of the reasons for the RL's low red line (6000rpm?)

There are 2 more benefits that are had with the type II head that CAN be retrofitted into the RL head:
1. Type II camshafts with slighly longer duration and different timing/lift.
2. Stiffer valve springs.

That being said... There are a few questions that havent been answered yet.

Is the 1mm larger valve worth all the work required to do this?
What is the RPM limit for the RL's drivetrain?
Mike Diaz, What RPM limit are you running on a daily basis with the RL heads?

My theory is that its not worth the extra work and expense, therefore I am going to eventually retrofit the RL heads with the type II cams and valve springs.

There is also another problem with using the type II heads, and DV8 I think you can most benefit from this. because of the different deck heights the cam centerline is offset. I think this could be solved with Buzzards cam wheels. I'm not an engine builder and I wouldn't even know how to get cams back into centerline, but I know it has to be done.

Also, and this is more of a question than anything. The 3.5 is a "stroker" motor. Doesn't this mean that high RPM performance is somewhat limited no matter what you do?

-Matt

mweber88 · 03-01-07, 08:31 AM

Matt--

Considering you said the 3.5 isn't any wider, now we have to check a few other things to be sure...

1. Measure the distance between the cams, and
2. Measure the distance from one cam to the crank

Do this for both the 3.5 and the 3.2 and we'll have an answer. Unfortunately, I don't have a 3.5 with which to do this, so I can't help much.

If indeed the 3.2 cams are indexed differently than the 3.5, then using adjustable cam sprockets and degreeing in the cams would be a good thing.

Let me know about those measurements, as I'm way curious. Also, if you can get me some pics of the valve train in both the 3.2 and the 3.5, I'd like to see those differences, too.

Mike

BUZZARD · 03-01-07, 10:11 AM

We have a 3.5 being delivered during the week. Will be making solid spacers to replace the springs on the 35 rocker assembly.

Chris

sr5guy · 03-01-07, 11:29 AM

Quote:

Originally Posted by Dv8

Wasnt that expensive to have the manifold widened and im sure an adapter plate could be made. An argument can be made eitherway. With the webcams the 3.5 engine continues to make power past 7k no problem. My shift light is set at 7 and shift there everytime i drive the car.

Alright, my main question is if the 1mm larger intake valve is worth all of the headache of installing the type II heads on the 3.5. I'm talking in a dollars to horsepower sense, I know the larger valve is beneficial, but in what sense and how much of it?. That is good to see that your 3.5 is making power after 7K. This probably means that the increased stroke isn't significant enough to make a difference.

Quote:

Originally Posted by Dv8

I remember Kenso and I discussing this a while back, and he had mentioned that the cams are located in the exact same centerline on both heads and that the additional height came from above.
Your not talking about degreeing the cams are you?

The cam might be on the same centerline on the 3.2 and 3.5, but when the 3.2 heads are installed on the 3.5 I'm almost positive that the centerline is off. You demonstrated this yourself. You mentioned that the RL's timing belt was one tooth longer than the Legends. You said that when you installed the type II heads, that you had to use the Legend's shorter timing belt on your setup. Obvously there is some kind of difference in there and this is why I think your center-line is off.

Quote:

Originally Posted by BUZZARD

We have a 3.5 being delivered during the week. Will be making solid spacers to replace the springs on the 35 rocker assembly.

Chris

Thats what I wanted to hear, keep us posted and get yourself a camera. I want to see some of your work.

sr5guy · 03-01-07, 11:38 AM

Quote:

Originally Posted by mweber88

Matt--

Considering you said the 3.5 isn't any wider, now we have to check a few other things to be sure...

1. Measure the distance between the cams, and
2. Measure the distance from one cam to the crank

Do this for both the 3.5 and the 3.2 and we'll have an answer. Unfortunately, I don't have a 3.5 with which to do this, so I can't help much.

If indeed the 3.2 cams are indexed differently than the 3.5, then using adjustable cam sprockets and degreeing in the cams would be a good thing.

Let me know about those measurements, as I'm way curious. Also, if you can get me some pics of the valve train in both the 3.2 and the 3.5, I'd like to see those differences, too.

Mike

I would, but its too late now, the motor is in the car and its not coming apart to take measurements - plus the boss wouldnt be too happy. Maybe Telion, swift or buzzard can take some.

Regarding centerline, see my post above. The cam centerlines may be the same on the 3.2 and 3.5, but when you put the 3.2 heads on 3.5 I'm pretty sure they're off. You would need 3 measurements - 3.2, 3.5 and 3.5with 3.2 Heads.

Here is Kenso's post with the pictures of the different valvetrains:

Dv8's Legend (Chronicles and Articles)

Kenso · 03-01-07, 01:43 PM

The heads are the same height. The 3.5 block has a taller deck height so the distance from the crankshaft to the camshafts is increased, therefore requiring the longer t-belt. The difference in the heads is the location of the ports in relation to the rest of the head. The ports in the RL heads sit lower than the ports in the 3.2 heads. I'll have to check and see if the distance from cams to crank is the same with either set of heads, but I believe it is. Also I'm under the impression that Christian used the RL t-belt which would support this theory. The RL block is wider at the top by a small margin, but the intake ports in the heads are offset to compensate, which is why the intake manifolds freely interchange.

Turns out that the exhaust ports aren't relocated to compensate for the added deck height. However, when you use RL exhaust manifolds the 3.2 y-pipe fits ok, so the compensation must lie in the layout of the exhaust manifolds.

Looking forward to your results Matt. Not a bad idea on the mount, maybe not the prettiest thing ever but if it holds that's all that matters. I like your idea of making a jig that mounts onto the diff.

**Mike Diaz** · 03-01-07, 02:12 PM

My redline is 6400 RPM right now, but definitely can rev higher than that.

I usually shift at 5500 rpm.

*Dv8* · 03-01-07, 02:57 PM

I see your argument and respect it. It may not make sence to spend a lot when you can rework the RL heads to fit most of the TYPE II parts, I was even considering this. However for your average joe starting this project the TYPE II parts needed to swap need to be purchased from somewhere and thats an expense on the same level as a modified manifold or spacers.

Two facts still remain for me personally to make the swap myself because I have all the T2 parts already.

1, it hasnt been done yet(T2 parts swap over rl head-running).
2, the RL valvetrains missing those two cam caps and we are unaware whether it will hold up to high rpm power reliably.

With that said, i get flak for using the RL manifold, and will be testing out a TYPE II shortly. The TYPEII manifold is great for topend-so ive heard...

, if the rl head cant or is in danger of reving high then the mods would offset slightly dont you think?

Im still ? on the centerline. If my cams are offset whats the disadvantage? Im not sure I understand.

~Dv8

Quote:

Originally Posted by sr5guy

Alright, my main question is if the 1mm larger intake valve is worth all of the headache of installing the type II heads on the 3.5. I'm talking in a dollars to horsepower sense, I know the larger valve is beneficial, but in what sense and how much of it?. That is good to see that your 3.5 is making power after 7K. This probably means that the increased stroke isn't significant enough to make a difference.

The cam might be on the same centerline on the 3.2 and 3.5, but when the 3.2 heads are installed on the 3.5 I'm almost positive that the centerline is off. You demonstrated this yourself. You mentioned that the RL's timing belt was one tooth longer than the Legends. You said that when you installed the type II heads, that you had to use the Legend's shorter timing belt on your setup. Obvously there is some kind of difference in there and this is why I think your center-line is off.

Thats what I wanted to hear, keep us posted and get yourself a camera. I want to see some of your work.

Kenso · 03-01-07, 07:53 PM

Here's a pic of the heads side by side, Type 2 on the left and RL on the right. You can see how the intake ports are lower in the RL heads. After looking at the heads and measuring the distance from the cams to the bottom of the heads, I don't see any cam timing issue by using the Type 2 heads on the RL block. It's easier to use the RL heads as we've established, but as far as this relates to Christian, his cam timing should not have been thrown off.

sr5guy · 03-01-07, 08:03 PM

Quote:

Originally Posted by Kenso

Here's a pic of the heads side by side, Type 2 on the left and RL on the right. You can see how the intake ports are lower in the RL heads. After looking at the heads and measuring the distance from the cams to the bottom of the heads, I don't see any cam timing issue by using the Type 2 heads on the RL block. It's easier to use the RL heads as we've established, but as far as this relates to Christian, his cam timing should not have been thrown off.

Awesome picture, ken. Thanks for clearing this up. I knew the intake ports were a different design, but I wasn't sure that the heads were the same height. The only question I have left is if cam and/or cam sprocket is indexed differently.

-Matt

Kenso · 03-01-07, 08:07 PM

Quote:

Originally Posted by sr5guy

Awesome picture, ken. Thanks for clearing this up. I knew the intake ports were a different design, but I wasn't sure that the heads were the same height. The only question I have left is if cam and/or cam sprocket is indexed differently.

-Matt

Good thought. I'll check that out to be sure.

sr5guy · 03-01-07, 08:13 PM

Quote:

03-01-07, 01:43 PM	#98 (permalink)
Kenso Registered User Join Date: Apr 2003 Location: NC Posts: 2,927 Car 1: 91 L Coupe 6 spd Car 2: 95 FZJ 80 Car 3: ITR 00-106 iTrader: (19)	The heads are the same height. The 3.5 block has a taller deck height so the distance from the crankshaft to the camshafts is increased, therefore requiring the longer t-belt. The difference in the heads is the location of the ports in relation to the rest of the head. The ports in the RL heads sit lower than the ports in the 3.2 heads. I'll have to check and see if the distance from cams to crank is the same with either set of heads, but I believe it is. Also I'm under the impression that Christian used the RL t-belt which would support this theory. The RL block is wider at the top by a small margin, but the intake ports in the heads are offset to compensate, which is why the intake manifolds freely interchange. Turns out that the exhaust ports aren't relocated to compensate for the added deck height. However, when you use RL exhaust manifolds the 3.2 y-pipe fits ok, so the compensation must lie in the layout of the exhaust manifolds. Looking forward to your results Matt. Not a bad idea on the mount, maybe not the prettiest thing ever but if it holds that's all that matters. I like your idea of making a jig that mounts onto the diff. __________________ ITR 00-106 91 6spd coupe 95 FZJ-80 George Carlin on the American Dream (NWS) Last edited by Kenso : 03-01-07 at 06:14 PM.

03-01-07, 02:12 PM	#99 (permalink)
Mike Diaz WHAAAAAH! Join Date: Jan 2002 Location: N Canton, Ohio Posts: 10,989 Car 1: 3.5L 1991 LS Coupe 5 Spd Blk/Blk Car 2: 1994 Civic EG Hatch Car 3: 03 Honda TRX400EX iTrader: (2)	My redline is 6400 RPM right now, but definitely can rev higher than that. I usually shift at 5500 rpm. __________________ 2nd Gen FAQ \| Newbie FAQ \| Bleeding Coolant DIY \| Manual Trans Flush DIY 3.5L DIY \| Crank-No Start Diagnosis \| How I built My Legend

03-01-07, 07:53 PM	#101 (permalink)
Kenso Registered User Join Date: Apr 2003 Location: NC Posts: 2,927 Car 1: 91 L Coupe 6 spd Car 2: 95 FZJ 80 Car 3: ITR 00-106 iTrader: (19)	Here's a pic of the heads side by side, Type 2 on the left and RL on the right. You can see how the intake ports are lower in the RL heads. After looking at the heads and measuring the distance from the cams to the bottom of the heads, I don't see any cam timing issue by using the Type 2 heads on the RL block. It's easier to use the RL heads as we've established, but as far as this relates to Christian, his cam timing should not have been thrown off. __________________ ITR 00-106 91 6spd coupe 95 FZJ-80 George Carlin on the American Dream (NWS)

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03-01-07, 08:31 AM	#94 (permalink)
mweber88 Registered User Join Date: Mar 2006 Location: Columbus, OH Posts: 440 Car 1: 1994 Acura Legend GS Black/Black 6-speed iTrader: (7)	Matt-- Considering you said the 3.5 isn't any wider, now we have to check a few other things to be sure... 1. Measure the distance between the cams, and 2. Measure the distance from one cam to the crank Do this for both the 3.5 and the 3.2 and we'll have an answer. Unfortunately, I don't have a 3.5 with which to do this, so I can't help much. If indeed the 3.2 cams are indexed differently than the 3.5, then using adjustable cam sprockets and degreeing in the cams would be a good thing. Let me know about those measurements, as I'm way curious. Also, if you can get me some pics of the valve train in both the 3.2 and the 3.5, I'd like to see those differences, too. Mike

03-01-07, 10:11 AM	#95 (permalink)
BUZZARD Registered User Join Date: Oct 2004 Location: Newcastle Australia Posts: 503 Car 1: C32A race engines iTrader: (0)	We have a 3.5 being delivered during the week. Will be making solid spacers to replace the springs on the 35 rocker assembly. Chris