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What needs to be done on a Penta 531 to work in a brick?

I know this is a subjective experience. However, after installing my worked over 405 head on my B21FT. There was no loss of low end torque. In fact it runs better than before at all rpms from idle to redline. The only thing worse is the mileage because now it's fun to rev it to 5k all the time. The other mileage issue is the non heated o2 sensor which would probably give me back some highway mileage if I change to a heated sensor.

The 405 was built with street performance in mind keeping good low rpm torque. So the valve sizes stayed stock. The shop did a lot of work on the bowls and ports. I gotta say it runs great and I wouldn't hesitate to go this way again. Usea a enem V15 turbo cam. Stock volvo large valve springs. Revs to about 7k but I try to keep it around 6k. These engines respond very well to head work. I know at the power level you are referencing it may not be needed. But it sure made the engine a more pleasant beast.
 
I just re-read the whole thread and am also bummed that Jonathan never got around to actually posting his info. In addition to that let down, how much of this applies when you're talking a NON-modified 530 vs a non-modified 531? Obviously, the port volume differences still apply, but if you DON'T modify your 530 head, is it still better? Probably.

Also, what's your experience with lash caps under the bucket and shims over the bucket? I'm sure the camshaft design(ENEM C2 of sorts) has a lot to do with it. See here: http://forums.turbobricks.com/showpost.php?p=6012446&postcount=118
 
Also, what's your experience with lash caps under the bucket and shims over the bucket? I'm sure the camshaft design(ENEM C2 of sorts) has a lot to do with it. See here: http://forums.turbobricks.com/showpost.php?p=6012446&postcount=118

I haven't done lash caps and a standard volvo shim and bucket setup, but I wouldn't hesitate. They key with lash caps is to get ones that actually fit tight onto the tip of the valve, and also have a deep enough pocket. Some of the cheap-o ones are not that deep and are very loose on the ID. No bueno.

If you need a large lash cap, I'd just switch over to single-groove vw valves. Which you can get in steel, SS, inconel, Ti. They setup great in a Volvo 8v when the cam base circle is reduced ~3mm. I can show you if you swing by sometime. Then there's some PAC and other beehive springs that are near drop in. So it all just gets easier as the cam base circle gets smaller.
 
I just re-read the whole thread and am also bummed that Jonathan never got around to actually posting his info. In addition to that let down, how much of this applies when you're talking a NON-modified 530 vs a non-modified 531? Obviously, the port volume differences still apply, but if you DON'T modify your 530 head, is it still better? Probably.

Also, what's your experience with lash caps under the bucket and shims over the bucket? I'm sure the camshaft design(ENEM C2 of sorts) has a lot to do with it. See here: http://forums.turbobricks.com/showpost.php?p=6012446&postcount=118

Lash caps work just adjusting valve lash is a pain. My original setup had poor valve spring choice from RSI, I got valve float on the rev limiter and allowed a lash cap to dislodge and hang #1 exhaust open. Luckily caused no actual damage.

I've gone through the head now and retained the lash cap-under arrangement. Caps are Manley bought to spec, valvetrain is fancy Ferrea stuff now and the cam followers are from SuperTech (37mm).

The added difficulty in adjusting lash is inconvenient but my car is limited use so it wasn't a big deal to me.
 
I'm glad to hear you didn't have any damage! My concern was more with running lash caps in conjunction with the stock buckets and shims in them. I heard back from Reine though:

Me:
I do have one more question for you. I have a camshaft available to me that has a smaller base circle than stock by about 2mm that I am considering running. In your experience, is it safe to run lash caps and shims in the buckets at the same time? The camshaft’s profile is similar to your R33-264-14.0 from the specifications, so it’s pretty aggressive. I do have valve springs set up for 14mm of lift with stainless steel 46/38mm valves, but I am still cautious to run both shims and lash caps at the same time. The last engine this camshaft was in blew a rod through the block and I couldn’t find one of the lash caps after disassembly.

Am I worried about nothing and it’s common for people to run both, or should I set the clearances a different way and just use shims or lash caps to set the clearance?

Reine from AGAP:
I do not feel it is a problem to use lash caps, the ones I sell sits 2.5 mm down on the valve stem, so for those to come loose it need to be valve float with at least 2.5 mm, if that is happening it would just be a matter of time for something else to brake if there are no lash caps to come loose. The engines that I hear of with these kind of problems is if there are very aggressive, engine speed limiter or launch controls.
 
The lash caps I have(only 6, I thought I had 7?), are all 1.5mm thick but two are 3.5mm tall where the other two are 4.5mm tall.

I will just put the camshaft in and measure the clearances then likely order a new set of matching lash caps.
 
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