grey99max building another 3.5
05-20-2009, 02:33 PM
#161
Sounds like you do a fair amount of head porting there - and thanks for the tip on Summitt stocking bulk porting abrasives. I probably will never go nuts on a head like you did, but port matching is important to keeping the flow going, so that will continue.
I've already checked the exhaust ports and they matched the header plates pretty well, so no real work needed there. Cosworth did not open up the exhaust ports beyond the stock opening, so the present 1-5/8" OD tubes will be fine for the new engine.
I will start off with the present SSIM manifold, but if the new engine performs well, I'll look at going to something with less restrictions in the intake path. The Jenvey ITB packages look awfully good.... maybe the Xmas after next...
.
I've already checked the exhaust ports and they matched the header plates pretty well, so no real work needed there. Cosworth did not open up the exhaust ports beyond the stock opening, so the present 1-5/8" OD tubes will be fine for the new engine.
I will start off with the present SSIM manifold, but if the new engine performs well, I'll look at going to something with less restrictions in the intake path. The Jenvey ITB packages look awfully good.... maybe the Xmas after next...
.
Do it!I didn't open up the exhaust ports on the head any. They already matched the OEM exhaust gaskets and the headers. But, just a rule of thumb, if the headers are slightly bigger than the exhaust ports on the heads, you don't want to match them. It's best to leave the exhaust ports the size they already are since that small lip will help exhaust gases from being sucked back into the head. It's minor, but something I kept in mind while porting my heads.
06-08-2009, 01:29 PM
#162
LandShark has Cosworth
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More ITBs ...
Speaking of ITBs, look at these guys:
http://www.extrudabody.com/
and:
http://extrudabody.com/Products/ITBs.html
and three views of a VQ35 ITB:
http://s307.photobucket.com/albums/n...tDBC_1523c.jpg
http://s307.photobucket.com/albums/n...tDBC_1525c.jpg
http://s307.photobucket.com/albums/n...tDBC_1525c.jpg
Reminds me of LEGOs.... now if I can find a price....
.
http://www.extrudabody.com/
and:
http://extrudabody.com/Products/ITBs.html
and three views of a VQ35 ITB:
http://s307.photobucket.com/albums/n...tDBC_1523c.jpg
http://s307.photobucket.com/albums/n...tDBC_1525c.jpg
http://s307.photobucket.com/albums/n...tDBC_1525c.jpg
Reminds me of LEGOs.... now if I can find a price....
.
06-21-2009, 06:57 PM
#165
06-21-2009, 07:27 PM
#166
LandShark has Cosworth
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Hummm... the only improvement I can think of is to build a Cosworth-based 3.5 L engine for your car !
06-21-2009, 07:59 PM
#167
Yeah, this engine will be ... special ... but it's nothing compared to the car you're building. Just reading your thread wears me out - that's a tremendous amount of crafting and plain old hard work there. What you didn't paint, you chromed.
Hummm... the only improvement I can think of is to build a Cosworth-based 3.5 L engine for your car !
Hummm... the only improvement I can think of is to build a Cosworth-based 3.5 L engine for your car !
Cheers and keep up the good works
AA
07-15-2009, 07:38 AM
#169
LandShark has Cosworth
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Cosworth is shipping me a replacement set of cams (don't ask) so I can get back to building this engine. I was just starting to degree the cams and encountered a problem, spent some time corresponding with my vendor BoomBop and Cosworth, shipped the whole set of cams to California, and heard yesterday that they are replacing the set. 
In fairness to Cosworth, I think they got stuck with bad metallurgy from their cam manufacturer.
BoomBop is a class-act vendor. So far I've purchased my forged CP pistons and Cosworth ZK2 cams from them, and they have handled every part of the transactions with a professional can-do attitude.
In fairness to Cosworth, I think they got stuck with bad metallurgy from their cam manufacturer. BoomBop is a class-act vendor. So far I've purchased my forged CP pistons and Cosworth ZK2 cams from them, and they have handled every part of the transactions with a professional can-do attitude.
07-29-2009, 07:45 PM
#173
LandShark has Cosworth
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This fall.......
I just went out to a new digital truck scale and weighed the max - 3540 lbs. with me inside, 1/3 tank of fuel, and two full nitrous bottles sharing the truck with the sub and spare tire & jack. This is the Shark's fighting weight except I had the BFG DRs on instead of the M&H slicks - that might be 40 lb lighter.
The '03 Frontier tow truck weighed 4600 w/me, the Frontier with me and trailer weighed 6840 together, so putting the car on the trailer means I'm rolling at 10,140 lbs - plus all the tools, floor jack and crap I put in the truck on a track day. I roll pushing about 10,300 lb - no wonder I get 7.5 MPG!
I'm glad gas is back in the $2.30 range now.
I just went out to a new digital truck scale and weighed the max - 3540 lbs. with me inside, 1/3 tank of fuel, and two full nitrous bottles sharing the truck with the sub and spare tire & jack. This is the Shark's fighting weight except I had the BFG DRs on instead of the M&H slicks - that might be 40 lb lighter.
The '03 Frontier tow truck weighed 4600 w/me, the Frontier with me and trailer weighed 6840 together, so putting the car on the trailer means I'm rolling at 10,140 lbs - plus all the tools, floor jack and crap I put in the truck on a track day. I roll pushing about 10,300 lb - no wonder I get 7.5 MPG!
I'm glad gas is back in the $2.30 range now.
07-30-2009, 08:18 PM
#175
LandShark has Cosworth
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.. I just received a pair of American AR-23's 15 x 8 wheels to re-mount my 24.5 x 15 H&H slicks. They're on a pair of real lightweight M/T 15 x 10 wheels - which are too wide! The slicks are ripping themselves up on both the inner and outer areas of the tread. Really weird. The 23" M&Hs on 15 x 8 Outlaw IIs have OK tread, so I guess I should follow the manufacturers recommendations on rim size.
"it's always something"
.
08-17-2009, 07:52 PM
#177
LandShark has Cosworth
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All right - I'm gonna finish this motor assembly this week - had to take a week off work to do that...
Today's work - got both pairs of Cosworth cams installed in the heads, and the custom 3.0 timing gears and such are installed.
Tomorrow I'm going to degree in the cams - mostly to be sure everything is correct. Almost all parts you see are brand new, except for the two small chain guides. If timing is OK, then the outer timing cover, and lower and upper oil pans are next, along with the rear main seal, and of course valve covers.
Somewhere in between all that, I have a bell housing salvaged from a broken transmission, and I have a new starter in the mail, so I plan on spinning this engine over with oil in the pan to be sure everything is working before transplanting it into the car.
Today's work - got both pairs of Cosworth cams installed in the heads, and the custom 3.0 timing gears and such are installed.
Tomorrow I'm going to degree in the cams - mostly to be sure everything is correct. Almost all parts you see are brand new, except for the two small chain guides. If timing is OK, then the outer timing cover, and lower and upper oil pans are next, along with the rear main seal, and of course valve covers.
Somewhere in between all that, I have a bell housing salvaged from a broken transmission, and I have a new starter in the mail, so I plan on spinning this engine over with oil in the pan to be sure everything is working before transplanting it into the car.
08-18-2009, 07:26 PM
#180
LandShark has Cosworth
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I started off the day setting up the degree wheel - then decided to check the valve lash on all cam lobes, so I knew how I stood with valve clearance on the second set of Cosworth ZK2 cams. Not so good - the original valve clearances were set at .012-.013 by a machine shop, first doing some valve lapping and checking all the valve stems for correct height. Remember I had to buy a complete set of the special DLC HR lifters for these cams.
With the new cams replacing the cracked cams, I have valve clearances of .006" to .011" - only four of the 24 valves have acceptable clearance, and they are on the tight end of acceptable. So, I have two choices here. Since I have a complete list of the clearance on every lifter,, I can either try to dremel down the clearance bump on the underside of each lifter, or I can take the list and the lifters back to my machine shop and let them do it. I'll go visit them tomorrow and see what Steve thinks about this one.
Of course I tried the dremel on an old-style 3.5 lifter and I was able to remove .006" rather easily. The bump is made of some hard stuff, so it takes a while to get 'er down. This is do-able!
Bummer.
With the new cams replacing the cracked cams, I have valve clearances of .006" to .011" - only four of the 24 valves have acceptable clearance, and they are on the tight end of acceptable. So, I have two choices here. Since I have a complete list of the clearance on every lifter,, I can either try to dremel down the clearance bump on the underside of each lifter, or I can take the list and the lifters back to my machine shop and let them do it. I'll go visit them tomorrow and see what Steve thinks about this one.
Of course I tried the dremel on an old-style 3.5 lifter and I was able to remove .006" rather easily. The bump is made of some hard stuff, so it takes a while to get 'er down. This is do-able!
Bummer.
08-18-2009, 08:23 PM
#182
08-18-2009, 09:17 PM
#183
LandShark has Cosworth
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There are no better VQ35 heads on the market. The Cosworth ZK2 cams were designed to work with these heads. Put the whole package of my built short block together with the Cosworth heads and cams, and you have something special to spray nitrous with.
08-18-2009, 09:23 PM
#184
but with all the post modification that needed to be done to the heads, would it not have been more advantageous to just have a shop basically duplicate the work cosworth heads?!
if this was asked before sorry...have scrolled thru the thread in a while..
if this was asked before sorry...have scrolled thru the thread in a while..
08-18-2009, 10:25 PM
#185
?? Huh ?? Building an engine like this takes very close attention to all details. What screwed me up was the first set of Cosworth cams developing cracks - getting those replaced took a lot of time and conversations with the manufacturer and distributor.
There are no better VQ35 heads on the market. The Cosworth ZK2 cams were designed to work with these heads. Put the whole package of my built short block together with the Cosworth heads and cams, and you have something special to spray nitrous with.
There are no better VQ35 heads on the market. The Cosworth ZK2 cams were designed to work with these heads. Put the whole package of my built short block together with the Cosworth heads and cams, and you have something special to spray nitrous with.
08-19-2009, 02:34 AM
#186
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Cosworth heads are new cast blanks to Cosworth specs though, they cant be 'copied' or replicated.
However, I have been looking at some Nismo 46cc VQ35 heads which use the VQ30 combustion chamber design and reportedly outflow the Cosworth heads once oversize(Cosworth or Supertech) valves are fitted.
http://www.nismo.co.jp/en/products/c...ne/vq35de.html
However, I have been looking at some Nismo 46cc VQ35 heads which use the VQ30 combustion chamber design and reportedly outflow the Cosworth heads once oversize(Cosworth or Supertech) valves are fitted.
http://www.nismo.co.jp/en/products/c...ne/vq35de.html
08-19-2009, 07:36 AM
#187
with all the money shoved in to the heads, you'd think they'd come back flawless 
Here's what the flowbench numbers of my head work is.
Stock - 188.8 @ .200"
281.2 @ .500"
Ported - 228.9 @ .200"
318.7 @ .500"
There's a guy down here that does some of the best porting.
About a 37.5 CFM gain, which should be around 50hp on the top end and you can see there 40.1 CFM gain on the low. So if each CFM = around 1.4 HP you can see that the headwork alone will post around a 50hp increase
Here's what the flowbench numbers of my head work is.
Stock - 188.8 @ .200"
281.2 @ .500"
Ported - 228.9 @ .200"
318.7 @ .500"
There's a guy down here that does some of the best porting.
About a 37.5 CFM gain, which should be around 50hp on the top end and you can see there 40.1 CFM gain on the low. So if each CFM = around 1.4 HP you can see that the headwork alone will post around a 50hp increase
08-19-2009, 01:10 PM
#188
Cosworth heads are new cast blanks to Cosworth specs though, they cant be 'copied' or replicated.
However, I have been looking at some Nismo 46cc VQ35 heads which use the VQ30 combustion chamber design and reportedly outflow the Cosworth heads once oversize(Cosworth or Supertech) valves are fitted.
http://www.nismo.co.jp/en/products/c...ne/vq35de.html
However, I have been looking at some Nismo 46cc VQ35 heads which use the VQ30 combustion chamber design and reportedly outflow the Cosworth heads once oversize(Cosworth or Supertech) valves are fitted.
http://www.nismo.co.jp/en/products/c...ne/vq35de.html
the high compression is not what i want but I could just get lower compression pistons to counter balance it.
08-19-2009, 01:35 PM
#189
with all the money shoved in to the heads, you'd think they'd come back flawless
Here's what the flowbench numbers of my head work is.
Stock - 188.8 @ .200"
281.2 @ .500"
Ported - 228.9 @ .200"
318.7 @ .500"
There's a guy down here that does some of the best porting.
About a 37.5 CFM gain, which should be around 50hp on the top end and you can see there 40.1 CFM gain on the low. So if each CFM = around 1.4 HP you can see that the headwork alone will post around a 50hp increase
Here's what the flowbench numbers of my head work is.
Stock - 188.8 @ .200"
281.2 @ .500"
Ported - 228.9 @ .200"
318.7 @ .500"
There's a guy down here that does some of the best porting.
About a 37.5 CFM gain, which should be around 50hp on the top end and you can see there 40.1 CFM gain on the low. So if each CFM = around 1.4 HP you can see that the headwork alone will post around a 50hp increase
Cosworth heads are new cast blanks to Cosworth specs though, they cant be 'copied' or replicated.
However, I have been looking at some Nismo 46cc VQ35 heads which use the VQ30 combustion chamber design and reportedly outflow the Cosworth heads once oversize(Cosworth or Supertech) valves are fitted.
http://www.nismo.co.jp/en/products/c...ne/vq35de.html
However, I have been looking at some Nismo 46cc VQ35 heads which use the VQ30 combustion chamber design and reportedly outflow the Cosworth heads once oversize(Cosworth or Supertech) valves are fitted.
http://www.nismo.co.jp/en/products/c...ne/vq35de.html
08-19-2009, 01:47 PM
#190
LandShark has Cosworth
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http://www.cosworthusa.com/store/pc/...7&idproduct=68
http://www.cosworthusa.com/store/pc/...nt%20tests.pdf
Anytime you install new competition cams, you have to find compatible valve lifters and do exact measurements of the valve lash on each valve so you can buy the appropriate size of lifter. I had to do it twice since the first set of Cosworth cams developed cracks after installation.
If I thought any shop could have created a comparable set of heads for $4,000 with all the CNC work, valves and dual springs, I would have been there. ( well, maybe Aaron could have done it..)
Maybe some of you guys haven't done this before?
Last edited by grey99max; 08-19-2009 at 02:39 PM.
08-19-2009, 01:52 PM
#191
Wrong - the heads haven't been modified since Cosworth CNCed the Nissan blank castings, installed the +1mm stainless and inconel valves and installed the $1,100 dual valve springs and titanium retainers - except the only mod made was to tip off the valve stems and do an insurance lapping of the valve seats. The outcome is a head with flow numbers in the 420cfm range.
Anytime you install new competition cams, you have to find compatible valve lifters and do exact measurements of the valve lash on each valve so you can buy the appropriate size of lifter. I had to do it twice since the first set of Cosworth cams developed cracks after installation.
If I thought any shop could have created a comparable set of heads for $4,000 with all the CNC work, valves and dual springs, I would have been there. ( well, maybe Aaron could have done it..)
Maybe you guys haven't done this before?
Anytime you install new competition cams, you have to find compatible valve lifters and do exact measurements of the valve lash on each valve so you can buy the appropriate size of lifter. I had to do it twice since the first set of Cosworth cams developed cracks after installation.
If I thought any shop could have created a comparable set of heads for $4,000 with all the CNC work, valves and dual springs, I would have been there. ( well, maybe Aaron could have done it..)
Maybe you guys haven't done this before?
yea, I already stated I didnt know the cosworth were casted from blanks, I myself thought they were DE that were examine R&D'd and re-machined to their spec to flow out the numbers they stated.
We are just making suggestion/getting more information. I'm not sure about the others but i'd think for what you spend on those heads you should have zero problems with them. If the heads arent the problem then forgive me I'm mis-interpreting the problems at hand...
either way...good luck and looking forward to the completion
08-19-2009, 01:53 PM
#192
Wrong - the heads haven't been modified since Cosworth CNCed the Nissan blank castings, installed the +1mm stainless and inconel valves and installed the $1,100 dual valve springs and titanium retainers - except the only mod made was to tip off the valve stems and do an insurance lapping of the valve seats. The outcome is a head with flow numbers in the 420cfm range.
Anytime you install new competition cams, you have to find compatible valve lifters and do exact measurements of the valve lash on each valve so you can buy the appropriate size of lifter. I had to do it twice since the first set of Cosworth cams developed cracks after installation.
If I thought any shop could have created a comparable set of heads for $4,000 with all the CNC work, valves and dual springs, I would have been there. ( well, maybe Aaron could have done it..)
Maybe some of you guys haven't done this before?
Anytime you install new competition cams, you have to find compatible valve lifters and do exact measurements of the valve lash on each valve so you can buy the appropriate size of lifter. I had to do it twice since the first set of Cosworth cams developed cracks after installation.
If I thought any shop could have created a comparable set of heads for $4,000 with all the CNC work, valves and dual springs, I would have been there. ( well, maybe Aaron could have done it..)
Maybe some of you guys haven't done this before?
To be honest no, nothing this extensive and its all new to me as I am trying to learn about all of it as much as I can.
Thank you for the info, it helps to learn these things ahead of time
08-19-2009, 01:55 PM
#193
as you know Grey you are the first to buy these heads... I havent even seen anyone on my350z pick these up...so naturally we are here to watch plus learn all we can..
08-19-2009, 02:10 PM
#194
Cosworth makes great ****. Hell they made a VQ30 make 450hp at 8000+ rpms.
From the research I did back in the day, these heads are awesome. Anything this custom is gonna have lots of custom work, it will all be worth it in the end. At least you are doing it right
From the research I did back in the day, these heads are awesome. Anything this custom is gonna have lots of custom work, it will all be worth it in the end. At least you are doing it right
08-19-2009, 02:32 PM
#196
LandShark has Cosworth
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.
08-19-2009, 02:43 PM
#198
LandShark has Cosworth
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Cosworth heads are new cast blanks to Cosworth specs though, they cant be 'copied' or replicated.
However, I have been looking at some Nismo 46cc VQ35 heads which use the VQ30 combustion chamber design and reportedly outflow the Cosworth heads once oversize(Cosworth or Supertech) valves are fitted.
However, I have been looking at some Nismo 46cc VQ35 heads which use the VQ30 combustion chamber design and reportedly outflow the Cosworth heads once oversize(Cosworth or Supertech) valves are fitted.
08-19-2009, 08:25 PM
#200
LandShark has Cosworth
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You're kinda right - normal price on the heads is around $4,600 with the valve train ( special +1mm valves. dual valve springs) installed. The ZK2 cams are normally $1,400 from most distributors.
I got deals on the heads and cams. $4,000 + $1,100.
The DLC HR valve lifters are $17.38 each and you need 24 of them. That adds another $430 to the price. Then you need intake and exhaust manifold studs because they're not included - about another $100 for stainless.
Finally you need a machine shop to top the valve stems and measure valve clearances for each valve (you don't know which size lifter you need until this step is done). Thats another $300-$500. It goes on from there - you gotta get all those new parts all installed and working together. Whew.
Then there's the rest of the engine.... I just my new starter this afternoon. I have this bell housing, so my plan is to finish the assembly once the HR lifters are trimmed to fit the new cams, then crank it over and measure the oil pressure and look under the valve covers for circulation.
Last edited by grey99max; 08-19-2009 at 08:28 PM.