BBC 990 head porting

[KonaJet74]

Can someone suggest a cyl head porter in
Norcal who has experience with the big port
990's? I'm looking for a little more out of the
LS6 in a 18' jet, Thanks in advance.........

[V-DRIVE VIDEO]

Can someone suggest a cyl head porter in
Norcal who has experience with the big port
990's? I'm looking for a little more out of the
LS6 in a 18' jet, Thanks in advance.........
For all your norcal Horsepower needs...
http://www.v-drivevideo.com/jerrysgallery/albums/userpics/Joey_Grose~0.jpg

[Machinist]

I have a guy who is top notch with big block chevy motors, and works magic with the grinder...30+ years porting and building motors.
He is in the north bay - PM me for contact info, I don't want to just post it up.

[squirt]

In the Bay Area you can give Gromm Racing Heads a call they are in San Jose (408) 287-1301

[396_WAYS_TO_SPIT]

For all your norcal Horsepower needs...
http://www.v-drivevideo.com/jerrysgallery/albums/userpics/Joey_Grose~0.jpg
Kick azz work out of that shop;)

[KonaJet74]

SWEET!!! I'll make some phone calls. Do these people mainly
do street cars & do any of them maybe specialize in marine
combos or? I know these 990's are pretty big and I've seen
in some chevy books they have been made to flow pretty good.
Im just wondering the difference between porting & a new set?

[GoCiggie31]

some other suggestions as well:
I agree with earlier post,Gromm Racing Heads off of Coleman by the Airport; very happy with past work
and
Morgans machine Shop in Walnut Creek...Tim Morgan little pricy but lots of experience 925-939-7346. He just did some 088's for me and I am looking forward to running my deep v.
good luck
personally, if I was to do it again, I would go with alum, AFR or Edel....good porting on cast iron heads from my experience is not cheap.

[Moneypitt]

Before you spend a bunch of money on those 990s PM Steelcomp, he has/had a set of Rher Morrison Brodex II heads quite reasonable...Check the spam section and search "Brodex"...............MP

[VDRIVERACING]

Why spend money on ancient designs? RHS, Merlin, Dart, etc... all produce cast iron heads that are superior right out of the box and have lots of potential from hi-perf to all out race. You can get them bare, complete, whatever. Check out the RHS website before you decide, then call someone like Grose for an opinion on the cost vs benefit. Besides, engine builders always have something laying around on the shelf for a bargain.

[steelcomp]

For what you're doing, your 990's will work just fine. You don't need to have them ported, but here's what you can do to really step them up.
1) have 2.25 intakes installed. The bowls are too big with the 2.19's and you can't get a decent valve job. the 2.25's will allow a nice 3 or even 4 angle valve job, and that right there will pick up flow tremendously.
2) The valve job...get a good quality performance valve job on both int. and ex.
3) Good valves with undercut stems, or have 11/32" liners installed and use 11/32" valve stems. Have the intake valves cut with a 28* backcut about .025-.030 wide. A good quality stainless valve like a Manley Pro Flow (or Severe Duty if you're running a roller) is worth the investment.
4) A little unshrouding in the chamber, mainly around the intake, will make a big difference. CC the chambers, as well...get them all equal.
5) blend the bowls under the valves. A quality bowl blend is 90% or what you're looking for.
Any decent performance shop will be able to do these things for you, and it shouldn't cost you any where near what a port job will. The ports on the 990's are borderline too big for a 454 in a jet boat, so you certainly don't want them any bigger. With the mods I mentioned, you'll have a really nice set of heads that can support plenty of power.
Lastly, take the $$ you were going to spend on porting, and have the heads flowed, then contact Chris Straub with all your engine details, and have a cam made for exactly what you're building. You can have all the porting in the world, but without the right cam, it's a waste of time, and you aren't going to find one off the shelf that's going to be exactly right. I can't emphasize this enough!! Have the heads assembled with the right springs, at the right seat pressure, with some quality Chromoly or Ti reatiners and hardened locks, and you'll have a nicer set of heads than most out there.
Good luck.

[VDRIVERACING]

You have not even paid for the improvements on your old technology heads yet, and they're already suggesting a custom grind cam, then what? Another mod or two, and someone's gonna tell you to get better heads; guaranteed. Better stock up on some hamburger helper...

[steelcomp]

You have not even paid for the improvements on your old technology heads yet, and they're already suggesting a custom grind cam, then what? Another mod or two, and someone's gonna tell you to get better heads; guaranteed. Better stock up on some hamburger helper...I'll put a stock 990 headed engine with the right cam against a ported 990 with some off the shelf salesman cam any day. Porting isn't all it's cracked up to be on 990's, and I believe this is what the guy was asking. I didn't see anywhere where he asked about an aftermarket head, and of all the things that can be done to improve an engine, having the right cam is no. 1. All the aftermarket parts and mods in the world won't make up for the wrong cam grind. Of course, that's just my experience, but WTF do I know? :notam:

[Speedin' Ian]

For what it's worth the guy who does our heads had the same opinion as Steelcomp. He did say they will benefit from a little work on the exhaust ports.

[VDRIVERACING]

I'll put a stock 990 headed engine with the right cam against a ported 990 with some off the shelf salesman cam any day. Porting isn't all it's cracked up to be on 990's, and I believe this is what the guy was asking. I didn't see anywhere where he asked about an aftermarket head, and of all the things that can be done to improve an engine, having the right cam is no. 1. All the aftermarket parts and mods in the world won't make up for the wrong cam grind. Of course, that's just my experience, but WTF do I know? :notam:
If you don't know what you know, how would someone who doesn't know you know what you know. Know what I mean? That aside, I agree with both your points, although they are irrelevant. I feel that as we have donated our life savings to engine parts that are also irrelevant and needless--in the bigger scheme of things--that we should share this way of life among any of those who are susceptable enought to be influenced by it. In other words, spend money on things they don't need. Now you and I are debating about which unneeded item to purchase. There is no such thing as a "little work". New cam, Oh you'll need better springs..Oh wait, you'll need the latest rockers...Oh, I forgot to tell you about the lifters YOU should have thought of.... and so on.
RHS heads out of the box are better than 990s and a better investment. Just because someone does not ask about an option, does not, IMHO, mean that option should not be presented to them for objective evaluation.

[GofastRacer]

Well, I don't know about ported 990's(I'm poor can't afford it)so I have to do my own shit so here's what I did, I spent a few hours just rounding off all the sharp edges(no hogging out) in the ports and smoothe out the chambers and gasket match, bolted them back on and run it without any other changes whatsoever and got 700 rpm more!.. Wonder what they'd do if I got serious with them???..:confused:

[VDRIVERACING]

Well, I don't know about ported 990's(I'm poor can't afford it)so I have to do my own shit so here's what I did, I spent a few hours just rounding off all the sharp edges(no hogging out) in the ports and smoothe out the chambers and gasket match, bolted them back on and run it without any other changes whatsoever and got 700 rpm more!.. Wonder what they'd do if I got serious with them???..:confused:
They may want to move in...:D

[GofastRacer]

They may want to move in...:D
LOL..:D

[steelcomp]

If you don't know what you know, how would someone who doesn't know you know what you know. Know what I mean? That aside, I agree with both your points, although they are irrelevant. I feel that as we have donated our life savings to engine parts that are also irrelevant and needless--in the bigger scheme of things--that we should share this way of life among any of those who are susceptable enought to be influenced by it. In other words, spend money on things they don't need. Now you and I are debating about which unneeded item to purchase. There is no such thing as a "little work". New cam, Oh you'll need better springs..Oh wait, you'll need the latest rockers...Oh, I forgot to tell you about the lifters YOU should have thought of.... and so on.
RHS heads out of the box are better than 990s and a better investment. Just because someone does not ask about an option, does not, IMHO, mean that option should not be presented to them for objective evaluation.You really don't know what you want to say, do you? I read the first version of this, and you're more full of shit than a Christmas goose. I never said a word about buying anything, nor am I debating the fact...I think you're delerious.
There are a ton of heads out there that are better than 990's out of the box. So what...now you're talking irrelevant. Here's your objective evaluation...stick with the topic...this is a guy with a 454 in a jet boat that's looking for a little more power. He's asking about porting a set of 990's for his app. and truth is, It's a waste of time and $$. That's a fact, not an opinion. In a v-drive, maybe not. If he said he had a TR w/ a pair of 750's, solid roller, 12.5:1, and a BC impeller, there might be some merit to porting, or an aftermarket head, but that's not the case. What I mentioned above is 90% of what is needed with 990's, especially in a jet. A little ex porting would ultimately be better, but not that much. You're not presenting an objective evaluation, you're just arguing for the sake of arguing. If you want an arguement, stick your head up your ass and argue with yourself about what's the best way out. (LOL...that was a joke, BTW)

[steelcomp]

Well, I don't know about ported 990's(I'm poor can't afford it)so I have to do my own shit so here's what I did, I spent a few hours just rounding off all the sharp edges(no hogging out) in the ports and smoothe out the chambers and gasket match, bolted them back on and run it without any other changes whatsoever and got 700 rpm more!.. Wonder what they'd do if I got serious with them???..:confused:That just tells me you moved the heads into a better operating range for your cam with the changes you made, 'cause you didn't change them much. A v-drive is also going to react differently than a jet to those changes.

[cfm]

How about more info on the engine build and etc before we jump on the ported head thing.
I know you said LS6 but this can mean two different compressions at the minimum.
What carb ?
What intake?
What cam ?
What compression ?
What exhaust ?
What impeller and what WOT rpm's do you get now ?
etc,etc,etc,etc

[VDRIVERACING]

You really don't know what you want to say, do you? I read the first version of this, and you're more full of shit than a Christmas goose. I never said a word about buying anything, nor am I debating the fact...I think you're delerious.
There are a ton of heads out there that are better than 990's out of the box. So what...now you're talking irrelevant. Here's your objective evaluation...stick with the topic...this is a guy with a 454 in a jet boat that's looking for a little more power. He's asking about porting a set of 990's for his app. and truth is, It's a waste of time and $$. That's a fact, not an opinion. In a v-drive, maybe not. If he said he had a TR w/ a pair of 750's, solid roller, 12.5:1, and a BC impeller, there might be some merit to porting, or an aftermarket head, but that's not the case. What I mentioned above is 90% of what is needed with 990's, especially in a jet. A little ex porting would ultimately be better, but not that much. You're not presenting an objective evaluation, you're just arguing for the sake of arguing. If you want an arguement, stick your head up your ass and argue with yourself about what's the best way out. (LOL...that was a joke, BTW)
Christmas goose? :idea:

[Moneypitt]

Christmas goose? :idea:
Next thing we know ol rattle can lou will be "poofing" in here in his santa suit........

[lilrick]

If you don't know what you know, how would someone who doesn't know you know what you know. Know what I mean? That aside, I agree with both your points, although they are irrelevant. I feel that as we have donated our life savings to engine parts that are also irrelevant and needless--in the bigger scheme of things--that we should share this way of life among any of those who are susceptable enought to be influenced by it. In other words, spend money on things they don't need. Now you and I are debating about which unneeded item to purchase. There is no such thing as a "little work". New cam, Oh you'll need better springs..Oh wait, you'll need the latest rockers...Oh, I forgot to tell you about the lifters YOU should have thought of.... and so on.
RHS heads out of the box are better than 990s and a better investment. Just because someone does not ask about an option, does not, IMHO, mean that option should not be presented to them for objective evaluation.
I understand what you are saying and I agree. I know about the money and the price to go faster. I think what NAPOLEAN-STEELCOMP was trying to say was that this guy just needs to put a lil money into his heads to spruce um up. Scott, you are a lil testy lately, did you forget your medication?:DLets all play nice.

[VDRIVERACING]

I understand what you are saying and I agree. I know about the money and the price to go faster. I think what NAPOLEAN-STEELCOMP was trying to say was that this guy just needs to put a lil money into his heads to spruce um up. Scott, you are a lil testy lately, did you forget your medication?:DLets all play nice.
I gotta stop chasing the bourbon with chardonney...;)

[jdf]

I gotta stop chasing the bourbon with chardonney...;)now that's a port job

[GofastRacer]

That just tells me you moved the heads into a better operating range for your cam with the changes you made, 'cause you didn't change them much. A v-drive is also going to react differently than a jet to those changes.
Actually the whole idea was NOT to change them but to make them more "efficient" since I wasn't turning rpm's to the moon and I got lucky and it worked, lol. Now with a 5500-6500rpm motor I wouldn't even consider 990's!..

[MikeF]

Now with a 5500-6500rpm motor I wouldn't even consider 990's!..
The more I read about this......the more it is true. A good set of oval ports on a normal sizes bbc (454-500) will do much better than a set of rectangle ports on an engine that only sees 5-6500 rpm. I just can't find a set of aluminum oval port heads that I like more than the Weldtech heads.....and I ain't about to shell out the $ for those. (as much as I'd like to):o

[MikeF]

I spent a few hours just rounding off all the sharp edges(no hogging out) in the ports and smoothe out the chambers and gasket match, bolted them back on and run it without any other changes whatsoever and got 700 rpm more!.. Wonder what they'd do if I got serious with them???..:confused:
Art, What rpm do you turn at max throttle/speed? What gears are in the box? What size engine?
:D

[GofastRacer]

Art, What rpm do you turn at max throttle/speed? What gears are in the box? What size engine?
:D
When I did this it was on a 440(.060 over 427)18 gears, 11x1/4-15 prop, 7400r's 106mph, that was on the clocks in the quarter, but let it run out it would go to 7700, no GPS back then so I don't know what the mph was at that rpm!..

[GofastRacer]

The more I read about this......the more it is true. A good set of oval ports on a normal sizes bbc (454-500) will do much better than a set of rectangle ports on an engine that only sees 5-6500 rpm. I just can't find a set of aluminum oval port heads that I like more than the Weldtech heads.....and I ain't about to shell out the $ for those. (as much as I'd like to):o
A set of 049's with the big valves and a clean up like I did on the 990's and you'd be surprised at the power they will make for a factory head!..

[Fiat48]

Put a blower on it and push that shit in there. And inject cool alcohol.
Hell I had to say something. :D

[lilrick]

A set of 049's with the big valves and a clean up like I did on the 990's and you'd be surprised at the power they will make for a factory head!..
I agree.. The jet just won't see the R's.

[steve d]

Put a blower on it and push that shit in there. And inject cool alcohol.
Hell I had to say something. :D
What took you so long?????????

[GofastRacer]

Put a blower on it and push that shit in there. And inject cool alcohol.
Hell I had to say something. :D
LMAO!..:D

[VDRIVERACING]

Put a blower on it and push that shit in there. And inject cool alcohol.
Hell I had to say something. :D
Now we're talking!!! It takes a lot of discipline to remain focused on cool, rather than silly things like "need" or "reality".... That's for people with bank accounts and 401K's.

[78Eliminator]

Porting, polishing, and CCing steel heads is asking for a severe neck ache!!!! So much faster with aluminum.

[GofastRacer]

Porting, polishing, and CCing steel heads is asking for a severe neck ache!!!! So much faster with aluminum.
You got that right!..:D

[wsuwrhr]

Porting, polishing, and CCing steel heads is asking for a severe neck ache!!!! So much faster with aluminum.
Not to mention the slivers

[78Eliminator]

Not to mention the slivers
You mean all the slag that flys off and trys to stick in your eyeballs from the carbide bit? lol

[KonaJet74]

Ok, here's the engine info;
-9:1 comp, forged TRW's
-Edelbrock performer rpm
-800 DP Holley
- MSD Ignition
- Berk w/ A Impeller
I didn't want any problems w/ comp/ pump gas issues,
so My engine builder suggested sticking w/ 9:1. I'm
sticking a Comp XM278 in it for now. I plan on probably
going with some other heads & a roller cam next season,
but I want to get it in the water this season, unless these
990's can be made to do the job? These jets go only as far
as the impeller will let them, So I'm just trying to get some
experience from you guys....... Thanks for the info!!!!!

[steelcomp]

Ok, here's the engine info;
-9:1 comp, forged TRW's
-Edelbrock performer rpm
-800 DP Holley
- MSD Ignition
- Berk w/ A Impeller
I didn't want any problems w/ comp/ pump gas issues,
so My engine builder suggested sticking w/ 9:1. I'm
sticking a Comp XM278 in it for now. I plan on probably
going with some other heads & a roller cam next season,
but I want to get it in the water this season, unless these
990's can be made to do the job? These jets go only as far
as the impeller will let them, So I'm just trying to get some
experience from you guys....... Thanks for the info!!!!!IMO, I wouldn't put much $$ into heads with those specs. You'd be $$ and performance ahead (for now) to find a good set of large ovals and go from there.
Save your $$ for the new heads and roller next year. The 990's will get you on the water, but I don't think you'll get the performance you'd like from them.

[gn7]

all the knowledge, welding rod, and $$$$$ in the world can't make them even close to a outa box canfields

[lilrick]

WOW!! with that engine combo, I would not even consider the 990 head. An oval port is a must. It will be a dog.

[KonaJet74]

I got the boat from a buddy, it had a stock 425hp solid
cam in it with a worn out pump and the 990's. It pulled
like a beast and ran great, it was no way near a dog.
It would pull 2 skiiers out no problem and pull real hard
throughout the RPM's. So, I'm hoping for the best.
Numerous people and engine shops suggested this cam
until I pull the hammer for the roller setup etc. I was
looking for a porter/flow bench so I could get the #'s
to Chris Straub, but I haven't had any luck. So, I decided
to put it together on the cheaper side because I'm also
rebuilding/painting the boat at the same time. I'll see how
it goes......

[squirt]

Yeah 990's will never work blah blah blah:rolleyes: . I just gained 350 rpm from putting on some stock 990's in place of 049's with the stock 425hp solid cam on an 8.5 - 1, 2 blolt short block . If you need flow numbers for Chris take your heads to Gromm Racing heads in SJ and it will be about 75.00 to have them flowed. I worked with Chris for a cam to go into the next motor with ported 990 replacements.........Guess it won't work either and Chris is all wet too:)
Don

[Roaddogg 4040]

Maybe you should just get a V-drive...:D By the way that was a joke, so don't get pissed...
Steve

[KonaJet74]

Thanks Squirt!!!! That's exactly what I was looking for!
I've heard these 990's do pretty good with some work.
Chris said to get them pocket ported & get some flow
#'s so he could get a cam for the setup. Thanks Don...
Eric

[squirt]

There are better heads you can use as said in this thread, but if you already have the 990's I'd use them. I wouldn't stick a bunch of $$$ into them but would go 1/3 the cost of a set of canfields. If more then I'd bite the bullett and get the better head.

[steelcomp]

all the knowledge, welding rod, and $$$$$ in the world can't make them even close to a outa box canfieldsYou wouldn't like to bet a new set of Canfields on that, would you?:)

[steelcomp]

Yeah 990's will never work blah blah blah:rolleyes: . I just gained 350 rpm from putting on some stock 990's in place of 049's with the stock 425hp solid cam on an 8.5 - 1, 2 blolt short block . If you need flow numbers for Chris take your heads to Gromm Racing heads in SJ and it will be about 75.00 to have them flowed. I worked with Chris for a cam to go into the next motor with ported 990 replacements.........Guess it won't work either and Chris is all wet too:)
Don
Well, hell, you're the customer, and the customer is always right, aren't they? :notam:
Again, it has more to do with the cam than the heads. Put the right cam with the 049's and the tables will turn in their favor, especially if you put the big valves in the 049's and do a little bowl blend. Get the right cam for the 990's and they'll work fine, just not "optimum".
One other thing...a jet dosen't suffer any where near as much from having too big of an intake port as something with a prop. You don't have to rely on a broad power band with a jet, so if it's a little lazy at 3000 rpm, you can get away with it. With a prop, it'd probably fall on it's face, so to speak.

[Daytona100]

Is it worth the extra cash to put the 2.25 intake valves in the 088 heads or put the bigger exhaust valves in a blown 454 deal?

[squirt]

Well, hell, you're the customer, and the customer is always right, aren't they? :notam:
One other thing...a jet dosen't suffer any where near as much from having too big of an intake port as something with a prop. You don't have to rely on a broad power band with a jet, so if it's a little lazy at 3000 rpm, you can get away with it. .
Customer isn't always right but was very realistic with his goal for the motor. There was a choice between the 3 sets of heads I had available here and the worked 990 replacements were the ones that fit the bill the best. It really wouldn't have mattered to me what set of heads I used as long as I could get to where I wanted. Had this been for a different boat or a bigger effort motor then I most likely would have went with a different head altogether. If it doesn't work out then I'll post up here and eat crow and won't blame anyone;)

[ERV JR]

What Size Valve Do You Put In The 049, When You Say Bigger Do You Mean A 2.19 Or Bigger ?

[GofastRacer]

What Size Valve Do You Put In The 049, When You Say Bigger Do You Mean A 2.19 Or Bigger ?
Yep, 2.19-1.88's!..