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Dan Jones
Dan Jones
St. Louis, Missouri
(280 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Assembled TA Rover Heads (getting ready for the flow bench)
Posted by: Dan Jones
Date: January 13, 2016 04:06PM

I just dropped off a set of assembled TA Rover heads (1.94" diameter intake valves, 1.6" exhaust) and Willpower single plane intake at a local cylinder head specialist. I removed the valves from one cylinder and he examined the ports, chamber shrouding, seat margins and valve angles and asked me some questions about the engine the heads will be going on (a higher compression 4.2L Rover), along with how I plan to use the car (Triumph TR8, purely street). He also asked if I was going to run EFI or a carb, suggesting you can get away with somewhat larger ports with EFI. He thought the size of the as cast ports were fine, needing only detail work, and that the best bang-for-the-buck would be to work around the existing valve job. He also threaded a spark plug in and indicated he would do a little chamber work around the plugs. Looking at the intake ports, he thought they should go to 250 CFM fairly easily which would be plenty for my application.

The plan is to flow bench the TA Rover head in as delivered condition then let him have a go at bowl porting and port matching the heads and intake. He indicated that getting the port floor of the intake manifold to work with cylinder head port floor was especially critical. I'm going to drop the block, gaskets (intake, exhaust and head), a header flange with pipe stubs and some bolts off this weekend so he can mock it up. I think I'll also take an OEM 4.6L Rover cylinder head along to flow bench as don't have any data on unported Rover heads.

Given the bore size and chamber design, he suggested no less than 11:1 compression and we briefly discussed camshafts. I mentioned the short block should handle a decent amount of RPM (cross-bolted mains, 3.03" stroke Rover nodular cast iron crank, Carrillo rods, forged flat top pistons) and I was considering running either a solid flat tappet or a hydraulic roller camshaft. He put the valve springs on a tester and said they were ideal for a hydraulic roller camshaft but recommended titanium retainers for a bit more RPM. He said they would also work with a solid flat tappet cam if offset locks were used to reduce the seat pressure. If running a solid flat tappet, he recommended using lifters with EDM holes supplying oil directly to the cam lobe/lifter face. On the tester, the springs were quite close to the advertised specifications. Note these assembled heads were delivered with TA's upgrade spring package for a hydraulic roller cam (TA p/n 1160) and have the following specs:

Dual springs without damper
O.D. 1.385
160 lbs @ 1.900"
360 lbs @ 1.400"
400 lbs/in
Coil Bind 1.175"
Max Lift 0.650"

He also likes the blue Viton metal clad valve seals, mentioning the white Teflon seals don't pass enough oil to the guides for most applications (uses them in race applications where the springs are flooded with oil over the top of the guides).

Dan Jones



Edited 1 time(s). Last edit at 06/23/2016 11:08AM by MGBV8.


DiDueColpi
Fred Key
West coast - Canada
(1365 posts)

Registered:
05/14/2010 03:06AM

Main British Car:
I really thought that I'd be an action figure by now!

authors avatar
Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: DiDueColpi
Date: January 13, 2016 07:50PM

That's pretty cool Dan.
Been a long wait to see what these heads are all about.
It will be exciting to get some numbers to run through the D5 to see what can be had.
Are you worried about shrouding? That's a pretty tight fit on the 94mm bore.

Live like you mean it.
Fred


Dan Jones
Dan Jones
St. Louis, Missouri
(280 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: Dan Jones
Date: January 14, 2016 11:51AM

> Are you worried about shrouding? That's a pretty tight fit on the 94mm bore.

A little. TA moved the valve centerlines to the center of the bore to be able to fit the larger valves so that will help with shrouding. We'll mock the heads up on the block to see what they look like. In the past, I've played around on the flow bench with moving the tube that replicates the cylinder wall closer to valves to test shrouding but that was with canted valves that unshroud themselves as they open so those results probably don't apply. The other issue with the relocated valves is piston-to-valve clearance. The notches in my forged pistons were cut for larger valve but in the original location. I may need to cut the notches larger.

Mike Tomaszewski of TA Performance posted the following on porting the TA Rover heads:

"On the exhaust have him start by opening up the exhaust outlet, make the port wider, The port will respond by doing this. Then have him removing very little to none on the back side of the exhaust bowl. Just blend the machined throat area into the back side. He should end up with a slight bump even, on the back side. Blend the rest of the bowl how he see fit."

I need to get a hold of Woody and see if he can provide an exhaust port template for his larger diameter tri-y headers. I've got a flange with pipe stubs but it's a generic part and may not match the TR8 headers. Also, the exhaust port is raised 3/4" on the TA heads so that may cause some header fit issues.

> It will be exciting to get some numbers to run through the D5 to see what can be had.

I recently updated to the latest version of Dynomation and it's predictions are quite a bit more optimistic than the previous version I was using. I had the previous version tweaked so that it did a good job in matching the engines we've had on the dyno. I need to spend some time with the new version to see if I can get a better match but luckily, I saved an older version off so I can switch between the two.

Dan Jones


MGBV8
Carl Floyd
Kingsport, TN
(4511 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
1979 MGB Buick 215

authors avatar
Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: MGBV8
Date: January 14, 2016 11:56AM

Quote:
I think I'll also take an OEM 4.6L Rover cylinder head along to flow bench as don't have any data on unported Rover heads.

Please do! I believe that the late 4.0 & 4.6 heads are the same.

Are you using custom pistons?


Dan Jones
Dan Jones
St. Louis, Missouri
(280 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: Dan Jones
Date: January 14, 2016 08:48PM

> I believe that the late 4.0 & 4.6 heads are the same.

Yes.

> Are you using custom pistons?

Yes but they were designed for different heads so the notches will likely have to be altered. I've got a dry sump 5.0L Rover V8 mystery motor with ported Rover V8 heads sitting at the dyno. Plans are to swap a set of ported 1964 Buick 300 heads and Huffaker intake on it but it would be interesting to try the TA heads on the 5.0L but chances are there will be piston-to-valve clearance issues due to the larger relocated valves.

Dan Jones


minorv8
Jukka Harkola

(268 posts)

Registered:
04/08/2009 06:50AM

Main British Car:
Morris Minor Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: minorv8
Date: January 15, 2016 01:38AM

I had the same problem with Merlin heads. Two sets of notches are not pretty...

It will be interesting to hear how the heads perform. Any ideas about the cam spec, I assume pretty stout ?

Jukka

Merlin notches.jpg


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: BlownMGB-V8
Date: January 15, 2016 11:34AM

Interesting that you guys are having to cut these valve notches. My 340 (with 300 heads) is zero decked (10.6:1 cr) and at .500 valve lift I had 1/4" of valve to piston clearance. Checked with clay. Of course, that was dynamic, not static clearance.

Jim



Dan Jones
Dan Jones
St. Louis, Missouri
(280 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: Dan Jones
Date: January 15, 2016 03:00PM

> I had the same problem with Merlin heads. Two sets of notches are not pretty...

What size valves do you have in your Melins? IIRC, Art's Merlins use 1.77" intake 1.5" exhaust valves.

> It will be interesting to hear how the heads perform.

Yes. It will be a awhile as I still have another car to finish up before getting serious about the Rover stuff.

> Any ideas about the cam spec, I assume pretty stout ?

Not yet. I'll wait until I have the cylinder head flow numbers in hand before designing the cam. The car is a street car so I don't want to get too carried away. The lift may be more than your typical Rover build since I can use up to a 1.7:1 rocker arm ratio. TA suggested 1.65:1 but, depending upon the lobes available, I might go 1.7:1 intake and 1.6:1 exhaust.

Dan Jones


minorv8
Jukka Harkola

(268 posts)

Registered:
04/08/2009 06:50AM

Main British Car:
Morris Minor Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: minorv8
Date: January 15, 2016 03:15PM

Jim, I did a dummy build without head gaskets and had some marks on the pistons. I have steel gaskets so the true clearance was marginal. So I cut the notches. Zero decked, steel gaskets and Rover 4,6 heads with 28 cc chambers. Should have had more clearance but did not. When I fitted Merlins I did not even bother to check, I simply cut the notches.

Dan, I have the std valves 1.73/1.40 somthing. The heads were modified with cnc machined seats last winter but ignition gremlins did not allow any chassis dyno runs. I am currently replacing the dizzy with coil packs ... Forget the KISS principle 😊


roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: roverman
Date: January 19, 2016 04:24PM

" 250 cfm" let's see...figure/figure, max power , 4.2L = 8200 rpm ? I hope you go with hyd. roller. IMHO 400lb springs will flat kill a rover F.T. cam(iron), lifter hole or not. Beehive springs, with their tiny steel retainers, would be a good cost to weight alternative, to ti retainers and heavy springs. Cometic head gaskets, a good idea. Let er rip ?
!


Dan Jones
Dan Jones
St. Louis, Missouri
(280 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: Dan Jones
Date: January 25, 2016 04:25PM

> " 250 cfm" let's see...figure/figure, max power , 4.2L = 8200 rpm ?

This is a street car so I'm thinking 7000 RPM. With the 4.2L, it looks like it only needs around 200 CFM of intake flow so I won't be taxing the heads. At least they'll have the flow should I decide to put them on a larger displacement engine.

> I hope you go with hyd. roller.

That's the plan. I've got some solid flat tappet cams in the parts stash that I could test for grins. One is a very high RPM unit (256/266 degrees @ 0.050 on a 108 LSA) with an advertised power range of 4000 to 8200 RPM. The other is more sensible 240 degrees @ 0.050" on a 110 LSA. Given the difficulties with breaking in flat tappet cams, I probably won't try either one.

Speaking of hydraulic rollers, Woody mentioned the cam grinder will only grind a 110 degrees lobe separation angle on his cam cores for larger durations and lift. With the relatively small valve Rover and Buick heads, he has seen better results with narrower lobe separation angles (down to 106 degrees LSA on his 4.9L stroker Rover). The larger valves in TA Performance heads don't want as narrow an LSA in a given combination. 110 LSA would be in the right ballpark on an engine like Woody's with the TA heads 1.94" diameter intake valves. Also Woody is looking into having some smaller hydraulic roller cam cores made for
smaller displacement Buick/Rover engines.

> IMHO 400lb springs will flat kill a rover F.T. cam (iron), lifter hole or not.

Agreed. The springs for the Schneider cam mentioned above are specified at 340 lbs/in.

> Beehive springs, with their tiny steel retainers, would be a good cost to weight alternative, to ti retainers and heavy springs.

Doug Herbert has inexpensive titanium retainers ($60 and up). I have beehives on another application with the tiny steel retainers but I've not checked if there is a drop-in beehive and retainer package that will fit the TA valves yet.

> Cometic head gaskets, a good idea. Let er rip ?

I'd like to use the commonly available 0.050" Rover gaskets. Looks like Fel Pro and Victor Reinz both list head gaskets for the larger bore Rover blocks but it's not clear what their compressed thicknesses are. I downloaded their catalogs but could not find the thickness specs. They list the same gaskets for both the early 3.9L/4.2L which used thin head gaskets and the 4.0L/4.6L engines which used the thicker ones.

I cc'd the pistons this weekend only to notice the dish in the piston is right where the quench pad is on the TA heads so, even with an 0.040" quench distance, there won't be a quench effect as the dish is another 0.040" deep. The pistons were designed for Rover/Buick heads which had no quench effect to speak of so it didn't matter at the time. Bugger.

Dan Jones


Dan Jones
Dan Jones
St. Louis, Missouri
(280 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: Dan Jones
Date: February 03, 2016 06:42PM

Just a quick update on the TA Rover heads. The head porter is supposed to get started on the Rover heads late this week. I dropped off the block, exhaust header flange, gaskets and head studs off last week so we could do a preliminary fit check prior to porting the heads. We positioned the TA heads and Willpower intake on the block without intake or head gaskets and the intake manifold bolt holes lined up with the holes in the heads and the intake ports were closely aligned with the unported TA head intake ports. Given the fact that the TA Rover heads are deeper, I expected the intake to sit up higher in the V and the holes in the intake need to be slotted but that wasn't the case. I assume TA must have adjusted those to match the wider head so the intake lines up. I didn't run the studs all the way down while I was there but the head bolt bosses are taller so its possible they won't be long enough. I'll check that this weekend. The blue Fel Pro Buick 300 intake gaskets (p/n 9944) are 0.042" thick and should work with the 0.050" Rover composite headgaskets. The gaskets are a decent fit but will likely need a bit of trimming and be shifted up perhaps an 1/8". I'll glue those to the intake before installation.

I discussed Mike's information on porting the exhaust side and we put machinist dye around the exhaust port and bolted a header gasket in place. Widening the port per Mike's advice, he scribed an outline. The resultant port is sized for a 1 1/2" ID primary tube header. That means a 1 5/8" OD. The TR8 tri-y TR8 headers from the Wedge Shop are available in two sizes:

Standard: 1 1/2" diameter primary, 1 3/4" secondary, 2" collector
Big Tube: 1 5/8" diameter primary, 1 7/8" secondary, 2 1/4" collector

I'll go with the big tube but the exhaust ports on the TA Rover heads are raised 3/4" and Woody says his headers tuck up close to the chassis so won't have the vertical clearance required. I'll have to cut and lengthen them.

My block appears to be unmilled and specs for the Buick 215 and Rover show a nominal deck height of 8.96". The forged pistons have a compression height of 1.25". Crank stroke is 3.03" and connecting rods are 6.2" center-to-center:

rod length + crank stroke/2 + piston pin height = 6.2 + 3.03/2 + 1.25 = 8.965"

If the block is 8.96", that would put the piston 0.005" out of the hole at TDC. Close enough to zero deck. In the parts stash, I have a couple of larger bore Rover headgaskets:

Rover ETC-7819 0.018" compressed thickness embossed head gasket
Rover ERR-7217 0.050" compressed thickness composite head gasket 3.77" bore

Unlike, the OEM Rover heads, the TA Performance Rover heads have a quench chamber. The usual quench distance goal is 0.040" +/-0.003" and the quench effect is supposedly negligible at 0.060". On the minimum side, you need enough clearance to compensate for piston rock at TDC and rod stretch at maximum RPM so the piston doesn't contact the head. Since aluminum blocks have a greater coefficient of linear thermal expansion, can probably run a little tighter quench. If I got my units correct, my back of the envelope calculation suggests maybe 0.006" difference between a cast iron and aluminum block for a 100 deg F temperature difference. Even factoring that in, the thinner headgasket is too thin to be safe. The thicker gasket will be thicker than desired but might be useable if the compression works out.

The combustion chambers are nominally 35 ccs but will get polished so will likely end up around 40 ccs. I cc'd the piston dish and valve notch at between 11 and 13 ccs, depending upon whether I cc'd them with alcohol or white sand. Compression with these assumptions and the thinner headgasket would be 10.85:1 and 9.89:1 for the thicker headgasket. A 0.040" thick headgasket would give 10.17:1 compression ratio and the goal quench. Given the aluminum heads, small 3.706" bore and expected cam overlap, I'd like to be at 11:1 compression. That would be no problem with quench heads and quench pistons but the custom pistons I have were designed for Buick/Rover heads which have no quench to speak of and are dished in the location of the quench pad on the TA heads. The pistons were also designed for heads with the valves in OEM locations but the TA heads have relocated them to the center of the bore to permit larger valves. From the initial mock up, I should be able to modify the existing valve pockets for clearance, though the extra cc's will have to be figured into the final compression ratio. Given that Woody runs 11:1 compression in some of his engines that use Rover or Buick 300 heads, I should be able to run 11:1 without the quench effect. We'll see where it all ends up during the final mock up assembly but I'll likely have to mill the heads to get the desired compression ratio.

I could buy another set of custom pistons designed for the TA Rover heads and swap the pistons over to the stock short block Rover 4.2L that I have. It will get ported OEM Rover heads but I'd also need to buy another set of 6.2" small (2.0") journal rods to make the compression height work out. Come to think of it, the guy I bought the parts of off tossed in a second set of 6.2" rods but I believe he said they weren't narrowed properly. Worth a look anyway.

I also dropped of an OEM Rover 4.6L head for flow testing.

Dan Jones


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: BlownMGB-V8
Date: February 04, 2016 12:49PM

That is really good information Dan. I'm very curious to see what numbers you get for the TA heads before porting, as eventually I may be buying a set for my 340. With the forced induction I will probably not port them, provided they are close to being on par with the stock cast 340 or 350 heads.

Jim


roverman
Art Gertz
Winchester, CA.
(3188 posts)

Registered:
04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: roverman
Date: February 04, 2016 07:03PM

Dan, Have you plotted dynamic compression(s), for your desired cam profiles ?


Dan Jones
Dan Jones
St. Louis, Missouri
(280 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: Dan Jones
Date: February 05, 2016 12:18PM

> Dan, Have you plotted dynamic compression(s), for your desired cam profiles ?

Not yet. The cam profile is a function of the head flow which I don't have in hand yet. I did some preliminary work based upon my ported Buick 300 head flow and assuming AFR 165 just to see how cam specs and expected power varies. Once I have the ported TA Rover head flow data, I'll plug that in. Dynomation plots pressure traces which should be more accurate than the dynamic compression calculators. However, the question becomes how much can a small bore cylinder withstand on 93 octane with and without quench. I know Woody has done several 11:1 engines with Rover and Buick 300 heads but I don't know the cam overlap and intake closing points associated with those engines.

Dan Jones



pcmenten
Paul Menten

(242 posts)

Registered:
10/08/2009 10:40AM

Main British Car:


Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: pcmenten
Date: February 05, 2016 12:49PM

Dan, I'm fascinated that you are being so attentive to the quench/squish effects. I think it is a low cost and under-appreciated way to optimize an engine. My machinist thinks I'm trying to squeeze more compression from the engine but I care less about the CR and more about combustion dynamics. I'll be very curious to hear your final results.


Dan Jones
Dan Jones
St. Louis, Missouri
(280 posts)

Registered:
07/21/2008 03:32PM

Main British Car:
1980 Triumph TR8 3.5L Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: Dan Jones
Date: February 12, 2016 03:22PM

Just got word from the head porter that the TA Rover heads should be ready for pickup next week. He said they flow near 260 CFM intake and 200 CFM exhaust. He noted that once you get past the intake port entries, the center of the ports looks like they were designed for a considerably larger displacement or higher RPM maximum effort application. If you raised the intake roof a 1/2" and epoxied the floor, he thought it would flow well over 300 CFM with a larger intake valve. Given the intake port sizing, he thinks the engine would run better with EFI than with a carb. He is really excited about the heads and the lightweight Rover/Buick engine and thought I should ditch the hydraulic roller, go solid flat tappet and spin it to 8000 RPM. He called a local engine builder over to look at the mock up of the heads, intake and block just because he thought it was so neat.

More when I pick up the parts and flow sheets.

Dan Jones


Nexxussian
Erik Johnson
Alaska
(62 posts)

Registered:
04/20/2015 10:32PM

Main British Car:
1974, MGB, Citroen Color Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: Nexxussian
Date: February 12, 2016 11:08PM

Dan, that is wonderful to know, thank you for posting. :)

I read in your post that the engine you are building is a 4.2.

How much larger displacement does your head porter think would be appropriate?

5, 5.3?


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: BlownMGB-V8
Date: February 13, 2016 10:21AM

With that kind of port flow I would think those heads would easily support a 350 cid build, and that is close to the practical limit for a SBB based engine. I think there was some speculation that you might get up to around 370 but I don't know of one that's been done yet.

Based on an engine like Chris Gill's 300 based 350 or my 340 based 350 it should be a potent package. You do pick up 80-82 lbs with the iron block but that's still a pretty light engine.

Jim


Nexxussian
Erik Johnson
Alaska
(62 posts)

Registered:
04/20/2015 10:32PM

Main British Car:
1974, MGB, Citroen Color Rover V8

Re: Assembled TA Rover cylinders (getting ready for the flow bench)
Posted by: Nexxussian
Date: February 13, 2016 07:22PM

Jim, I don't doubt it, 260 CFM is what the AFR 165s I've got on my 331 SBF are supposed to flow.

I know with that flow 5.4 liters makes for a "spirited" engine. ;)

A better way to phrase my question would have been "how much displacement do they recommend for your type of build?"

My favorite part of the port size vs displacement combination I have is how it's responsive lower in the rev range, but doesn't stop pulling till the limiters trip. :D

I've wondered what mine would be like on a 351 or 408 (5.8L & 6.7L, latter being a lower RPM torque monster I'm sure, ;) ).
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