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Grufton

Exhaust manifold swaps

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3 minutes ago, Snorman said:

Not being completely familiar with the car in question (stock engine, swap, etc.?) I wouldn't have an issue if it had 2 "front stock manifolds" instead of a "stock" "front and a rear". To me, those are stock to the car/engine. 

 

Is that different than having 2 intake cams?

 

 

 

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1 hour ago, Huggy said:

 

Is that different than having 2 intake cams?

 

 

 

It I if the only way the engine will fit in the chassis is if you use 2 intake cams, and the only difference between the intake and exhaust cam is a lug to drive a distributer.

 

If there's a lift/duration difference, then it should be points.

 

The stock manifold thing on the RX7 has to do with the path the rear manifold takes it points in a really funny direction, and swapping to a second front manifold provides a benifit only by making the manifold and the RF suspension not occupy the same space.

 

The front manifolds don't flow better, and if anything the rear manifold would be a better flowing piece if it didn't essentially point at Egypt.

Edited by SonsOfIrony
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5 hours ago, ABR-Glen said:

I like the way Jer is addressing this issue (I've driven his car BTW and I don't consider him a cheater, FWIW), he knows it was a contentious topic, so he's avoiding it even though the current rules are pretty much crystal clear that it's allowed. On the other hand, you guys seem to be justifying your option to run it, which is fine, I'm just trying to make the point that approach can have other consequences.

FYI, one car, that has plenty of points to spare is running the "Header", the green car is not and is actually where Jer saw you could make a cast manifold work. 

 

Get your point and honestly we always assumed this would close, hence why we found a way to make a cast one work at the beginning of last season and showed it to tech/staff. 

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On 1/21/2020 at 6:34 PM, shanehutton said:

These are the stock E46 manifolds

78f9ee14e451301cc7eaece20a47f914.jpg

Can someone help me to understand the situation by completing the following sentence?

 

"These manifolds can't be used on my race car because _______ ."

 

 

(and if the answer is "they contain catalytic converters", then you had better elaborate and explain why catalytic converters can't be installed on a race car and yet seem to be peachy as far as BMW AG is concerned)

Edited by enginerd
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On 1/22/2020 at 11:44 AM, Huggy said:

 

Is that different than having 2 intake cams?

You know, I probably don't have a problem if a twin-cam engine is running 2 stock and OE cams. I'm not talking about re-ground cams, cams from different model/generation, etc.. Stock cams to that engine, if a stock and OE intake cam is substituted for the exhaust cam, IMO that's free. 

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7 minutes ago, enginerd said:

 

"These manifolds can't be used on my race car because _______

Nate that's easy, they don't fit my car. 

 

On a more serious note is it the precat with the honey comb, it could be easily removed as I have done it on a couple 91 Lotus Elans and it breaths better and can be retuned.

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1 minute ago, 55mini said:

Nate that's easy, they don't fit my car. 

I meant for the e46 BMW situation running the stock engine and replacing those manifolds with e36 manifolds. My reading of the preceding posts left me thinking that this had nothing to do with swapped engines.. these manifolds came on the car from the factory, so they certainly fit.

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I understood the question, somedays we need some humor on this forum. I would fully agree with your above statement.

 

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Is this the tip of the iceberg?  Ecotec miata, GM ram horns, and E46/E36 are known (now).  Are there others?

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1 hour ago, Snorman said:

You know, I probably don't have a problem if a twin-cam engine is running 2 stock and OE cams. I'm not talking about re-ground cams, cams from different model/generation, etc.. Stock cams to that engine, if a stock and OE intake cam is substituted for the exhaust cam, IMO that's free. 

Sorry, same thing as regrinding only the intake or exhaust lobes of a single cam and calling it stock.

 

Change the stock lift and/or duration specs = 50 points. Enough freebies.

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On 1/21/2020 at 5:34 PM, shanehutton said:

 

These are the stock E46 manifolds vs two different OEM E36 options.  Based on the knowledge base wording, they are all allowed with zero points.  This is great news cause I have been wanting to run the Integra type R OEM manifold on my civic for free as well. 😎

 


 

78f9ee14e451301cc7eaece20a47f914.jpg

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Minimum of 2 points as per the Ram's horn precedent if the rules are to be fair, should be 10 for the performance increase. You don't think it's worth 10 points, use the stock manifolds.

 

Enough freebies. 

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6 minutes ago, mender said:

should be 10  25 for the performance increase similarity to FPV header rule. You don't think it's worth 10 25 points, use the stock manifolds.

 

Enough freebies. 

IMO

 

(aside)

This is how you get a huge rulebook. You put in some rules and then some people say "well what if I want this slightly different part, shouldn't this be less points?" And next thing you know, there's 4 different "fixed" values for exhaust pieces that aren't stock and it varies with make / model!!! Come on guys (tech @National Tech @Ray Franck), this rulebook should apply equally to all cars, there is no forking way an e46 team should get free non-OE manifolds.

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44 minutes ago, Grufton said:

Is this the tip of the iceberg?  Ecotec miata, GM ram horns, and E46/E36 are known (now).  Are there others?

 

Yes there are.

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Is somebody hung up on 25 points? I mean honestly. On a side note when can I start hacking up my E39 540i Sport 6 speed? 500 point car yet? 

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9 hours ago, Snorman said:

You know, I probably don't have a problem if a twin-cam engine is running 2 stock and OE cams. I'm not talking about re-ground cams, cams from different model/generation, etc.. Stock cams to that engine, if a stock and OE intake cam is substituted for the exhaust cam, IMO that's free. 

 

Free the cams!

 

On a serious not there is a very strange loophole to this for a certain platform. 

 

Pay money for free cam (not Chumpy)

 

Or

 

Cut the back of an exhaust cam off, re drill the timing gear to get timing right, install on intake side (Chumpy)

 

The cams in question are essentially the same. Same lift with slightly different duration. 

Edited by KoneKillah

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8 hours ago, mender said:

Sorry, same thing as regrinding only the intake or exhaust lobes of a single cam and calling it stock.

 

Change the stock lift and/or duration specs = 50 points. Enough freebies.

Ehh...not sure I agree. They're still "stock" and "OE" cams for that engine/make/model. I also don't think the gains/benefit would be anywhere near that of a custom reground or aftermarket cam. 

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11 minutes ago, TiredBirds said:

Is somebody hung up on 25 points? I mean honestly. On a side note when can I start hacking up my E39 540i Sport 6 speed? 500 point car yet? 

 

Here's my perspective:  I'm building an E46.  I have two powertrains on the floor right now, one is a M52tuB28 (500 pts), the other is a M54B25 (475 pts).  The 2.5 liter has just enough points for a header, but my thought has been that the extra 300 cc's are more valuable to me.  That thinking changed when I found out stock type manifolds are valued less than 25 pts. Now the 325 might have a few points to spare after easily dealing with the cats.  I'd love to have the E36 manifolds for free, but as much as I harp on no free stuff (particularly manifolds) it would be hypocritical not to speak up.

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26 minutes ago, Grufton said:

 

Here's my perspective:  I'm building an E46.  I have two powertrains on the floor right now, one is a M52tuB28 (500 pts), the other is a M54B25 (475 pts).  The 2.5 liter has just enough points for a header, but my thought has been that the extra 300 cc's are more valuable to me.  That thinking changed when I found out stock type manifolds are valued less than 25 pts. Now the 325 might have a few points to spare after easily dealing with the cats.  I'd love to have the E36 manifolds for free, but as much as I harp on no free stuff (particularly manifolds) it would be hypocritical not to speak up.

It looks like you are talking about a power difference of only 4hp....193 vs 189. I'd run the 189HP unit w/ headers, if both engines are in good shape. If not I'd just run the better mill given the headers are only going to net you MAYBE 10hp.  Removing all the emission junk will free up that. 

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1 hour ago, KoneKillah said:

 

Free the cams!

 

On a serious not there is a very strange loophole to this for a certain platform. 

 

Pay money for free cam (not Chumpy)

 

Or

 

Cut the back of an exhaust cam off, re drill the timing gear to get timing right, install on intake side (Chumpy)

 

The cams in question are essentially the same. Same lift with slightly different duration. 

If you take the exhaust cam and install it on the intake side, what will actuate your exhaust valves? Are you taking the intake cam and putting it in the exhaust side?

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22 minutes ago, enginerd said:

If you take the exhaust cam and install it on the intake side, what will actuate your exhaust valves? Are you taking the intake cam and putting it in the exhaust side?

 

Lock all the exhaust valves open for a free flowing system.  Less restriction that way.

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1 hour ago, Snorman said:

Ehh...not sure I agree. They're still "stock" and "OE" cams for that engine/make/model. I also don't think the gains/benefit would be anywhere near that of a custom reground or aftermarket cam. 

I like to think of these kinds of things as true or false questions.

 

Is the lift and/or duration the same as the factory spec for the intake and exhaust events?

True = 0 points

False = 50 points

 

You decide if the change is worth 50 points.

Edited by mender
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1 hour ago, mender said:

I like to think of these kinds of things as true or false questions.

 

Is the lift and/or duration the same as the factory spec for the intake and exhaust events?

True = 0 points

False = 50 points

 

You decide if the change is worth 50 points.

No, I get it. It's not applicable to us, but I respectfully disagree only because it's the stock or OE cam being used in the engine, albeit to control different valves. I probably would have thought differently a year or two ago, but opinions can change. 

Again, I completely agree that reground "OE" cams should be points. Whether true or not, there's been a lot of chatter among people in the series (who I talk to anyway) about certain platforms running these and getting away with it. 

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1 hour ago, mender said:

I like to think of these kinds of things as true or false questions.

 

Is the lift and/or duration the same as the factory spec for the intake and exhaust events?

True = 0 points

False = 50 points

 

You decide if the change is worth 50 points.

And apparently everything isn't true or false. 

 

Is the exhaust manifold the same as the factory spec manifold on the engine being claimed? 

True = 0 points

False = 2 points (since it's the same material as the OE manifold)

🤣

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2 hours ago, TiredBirds said:

It looks like you are talking about a power difference of only 4hp....193 vs 189. I'd run the 189HP unit w/ headers, if both engines are in good shape. If not I'd just run the better mill given the headers are only going to net you MAYBE 10hp.  Removing all the emission junk will free up that. 

 

It's not just about peak power.  IIRC the 2.8 has quite a bit more power under the curve, and more torque, so it'll pull harder across the rev range, not just at the peak.

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1 hour ago, Snorman said:

No, I get it. It's not applicable to us, but I respectfully disagree only because it's the stock or OE cam being used in the engine, albeit to control different valves. I probably would have thought differently a year or two ago, but opinions can change. 

Again, I completely agree that reground "OE" cams should be points. Whether true or not, there's been a lot of chatter among people in the series (who I talk to anyway) about certain platforms running these and getting away with it. 

 

Is your point the cam can be used like "re-purposed material" since it was original to the car, just not satisfying the same function?  I think the "old" rules would agree with you, but the new rules with things falling under the FPV system step on that creativity.

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