Generation IV Internal Engine - 418 head and cam ?s

I'm building a 418 stroker motor, and can't decide on best heads and cam to run, I plan on runnin 150 to 250 nitrous system, any suggestions? Thanks

How deep are your pockets? That is the question.

You can use pretty much any cathedral head you want on that motor. AFR 230's would be a good choice on this.

As far as rectangular port there is a slew of them. You can run and LS3 head or the aftermarket LS3's from MAST or PRC. You can also run a small bore LS7 setup like the PRC small bore LS7 heads or the RHS LS7 heads.

If I didn't have the heads or intake yet I would go LS7.

As far as cam, I would contact Geoff@EPS or PatG on here to custom spec you something. It's barely much more than an off the shelf cam.

Cool thanks, ya I haven't got the heads or intake yet but I was wanting to run a fast 102

There is a 102 for the LS7 heads.

The thing about it is that the stock LS7 intake breathes very well for an LS7 which is more cubes and can be had for half the price of a Fast 102.

I would just get an LS7 and maybe get it ported.

Thanks for the help ill probably go that route with a port job and run afrs hopefully

Thanks for the help ill probably go that route with a port job and run afrs hopefully

If you run AFR's then you are going to want to get a FAST intake because there is no factory cathedral intake that is going to flow the air for a 418.

The good thing about AFR's is that you can run the stock valvetrain unlike Trickflows because of the different valve guides.

The prc heads r u talkin about the 265cc or the 285cc would be best?

The prc heads r u talkin about the 265cc or the 285cc would be best?

You are going to want to use the 265 heads because the 285's need a minumum of a 4.125 bore and you only have a 4.080 bore

Ok thanks for the info

I would definitely recommend taking a look at our PRC LS7 small bore heads. They will fit on top of that motor and I would expect them to make some pretty good power. One of our customers recently put these heads on top of a 429 LS3 race motor. While it did have higher compression he was able to get 604 at the tire through a 4l80E transmission. While this is not the same as your setup it gives you an idea what these are capable of.

If you decide to stay with cathedral ports, you might want to consider Trick Flow 235 heads.

Thanks for the info guys its helping alot

If you decide to stay with cathedral ports, you might want to consider Trick Flow 235 heads.

Trickflow heads are badass, no doubt, but they have an added expense in having to use a roller rocker. So, if you spend that much money on a set of heads, you are not going to cheap out on some garbage rockers.

So in the end add a minumum of 500 bucks to the price of the heads.

Any other head can run the stock rockers of aftermarkets if you choose.

Trick Flow indeed recommends aftermarket roller rockers, but lots of folks are running stock rockers, usually with trunion upgrades. You need to shim the rockers though to get the geometry right. TEA has a kit with everything you need including the right length pushrods. Thunder Racing sells these kits.

Trick Flow indeed recommends aftermarket roller rockers, but lots of folks are running stock rockers, usually with trunion upgrades. You need to shim the rockers though to get the geometry right. TEA has a kit with everything you need including the right length pushrods. Thunder Racing sells these kits.

The trunion upgrade isnt needed but very helpful. But with the price of the kit to shim for stock rockers, trunion upgrade, and labor you may as well just buy aftermarket rocker kit! Im not saying to get a $1000 dollar set of Jesels or T&D's but for all those parts above and labor would probably equal out to a set of $500 dollar yella terras or harland sharps!

DONT GO CHEAP ON VALVETRAIN COMPONENTS!!!!

O yea back on topic(LOL, sorry OP) I would do the TFS 235 and a matched cam!

Call Phil @ AI, tell him your build, what its designed purpose is (dedicated track car, street/strip etc), how many miles a year you plan on driving it.....and he will hook you up with a knockout setup. I've run AI heads on 3 different motors, and all of them have run as well or better than other similar cube motors, running ANY other head combo. Don't get into chasing dyno #'s or flow #'s...

Thanks for the help guys. Its helped me out alot

I still vote for the LS7 heads. You have a better valve angle and a port that can move some serious air and have good port velocity doing it.

O yea back on topic(LOL, sorry OP) I would do the TFS 235 and a matched cam!

Agreed... heard good things about these. Going to consider them later this year when I hope to pick up a stroked LS3. Might look into a Pat G spec'd cam as well.

Go with afr heads and call Gabe Ray at Comp and he will spec the cam free! Afr v230 heads mine are p and p but they will push you well past 550 with a good cam and Intake setup!

Go with afr heads and call Gabe Ray at Comp and he will spec the cam free! Afr v230 heads mine are p and p but they will push you well past 550 with a good cam and Intake setup!

I would hope close to (or slightly over) 600FWHP with a FAST102/102 and the proper cam.

Like I said before...this is something you might want to consider...

http://www.ls1tech.com/forums/dynamometer-results-comparisons/1343577-advanced-induction-416-ci-hr-l92-vic-jr-714hp-na.html

Like I said before...this is something you might want to consider...

http://www.ls1tech.com/forums/dynamometer-results-comparisons/1343577-advanced-induction-416-ci-hr-l92-vic-jr-714hp-na.html

That motor was 13:1 comprression and runs on e85. The OP might not want that much compression and might not have access to e85 (like me).

Now here is an engine that is on pump and has L92's. It also has a stock intake which is a disadvantage compared to the vic jr. Just imagine if this engine had a vic jr?

http://www.ls1tech.com/forums/dynamometer-results-comparisons/680245-l92-418cid-tsp-stroker-chassis-dyno-results.html


http://www.ls1tech.com/forums/generation-iv-internal-engine/680286-tsp-640-hp-l92-engine-chassis-dyno-sheets-results.html#post6694298

Now also imagine if this engine had the small bore LS7 heads from PRC or RHS on it, which weren't available when your link or my links were made. It would most likely be on the ass or equal to that 714 hp motor with an LS7 small bore and single plane intake

Thanks for the info guys, keep it comin all opinions help

That motor was 13:1 comprression and runs on e85. The OP might not want that much compression and might not have access to e85 (like me).

Now here is an engine that is on pump and has L92's. It also has a stock intake which is a disadvantage compared to the vic jr. Just imagine if this engine had a vic jr?

http://www.ls1tech.com/forums/dynamometer-results-comparisons/680245-l92-418cid-tsp-stroker-chassis-dyno-results.html


http://www.ls1tech.com/forums/generation-iv-internal-engine/680286-tsp-640-hp-l92-engine-chassis-dyno-sheets-results.html#post6694298

Now also imagine if this engine had the small bore LS7 heads from PRC or RHS on it, which weren't available when your link or my links were made. It would most likely be on the ass or equal to that 714 hp motor with an LS7 small bore and single plane intake

Yes I understand the OP may not want that level of compression and reliance on race fuel. However depending on its intended use and car its going in, this motor shows the power potential of these AI L92's. An 11.5:1 up to as much as 12:1 have been successfully run on 93 octane. This would only result in a small reduction in power over the numbers posted in that thread. In fact, again depending on his use, the argument could be made that by running a larger HR cam or jumping to SR, you could result in minimal power loss over this motor.

I would caution against picking a popular-trendy set of heads, like some mentioned in this thread. Their are so many variables that go into making power. I ran the brand new PI 11deg cathedral head 215cc on my stock sb ls1, those heads had huge fanfare, superior valve angle etc. It didn't make as much power, nor was as drivable around town as the AI 5.3 218cc head (using same compression same cam same intake same exhaust, same tuner same dyno same weather). I would encourage the op to collect research. Talk to those who you know by reputation, that are more about helping you find the right part vs selling you a popular high margin option.

Its gonna be a weekend street car but track car with nos 1 weekend or so a monthim lookin around 11:1 or. 11.5:0

Yes I understand the OP may not want that level of compression and reliance on race fuel. However depending on its intended use and car its going in, this motor shows the power potential of these AI L92's. An 11.5:1 up to as much as 12:1 have been successfully run on 93 octane. This would only result in a small reduction in power over the numbers posted in that thread. In fact, again depending on his use, the argument could be made that by running a larger HR cam or jumping to SR, you could result in minimal power loss over this motor.

I would caution against picking a popular-trendy set of heads, like some mentioned in this thread. Their are so many variables that go into making power. I ran the brand new PI 11deg cathedral head 215cc on my stock sb ls1, those heads had huge fanfare, superior valve angle etc. It didn't make as much power, nor was as drivable around town as the AI 5.3 218cc head (using same compression same cam same intake same exhaust, same tuner same dyno same weather). I would encourage the op to collect research. Talk to those who you know by reputation, that are more about helping you find the right part vs selling you a popular high margin option.

The numbers of that motor would be very peaky with a single plane intake which would require the OP to have a big stall and gear to race with and make it more track oriented unlike what the OP just posted. Yes you can run 12:1 on pump, but L92 heads have shown no increase in power in going to that much compression. 11-11.4 is where you want to be with them on pump. Also, depending on the OP's car, the vic jr might not be an option. So he would be restricted by an intake that has to fit the car. Any style ls intake has it limits so going to 12:1 or SR is null and void because the intake will hold it back from letting that characteristic shine to its full potential. Down the compression of that motor, put an LS style intake on it, and change the cam and watch that AI headed motor make the same power as the PRC headed motor.

As far as the heads I would put the PRC L92's up against the AI L92's any day. They are both great heads and do really well. I've never mention any popular or trendy head. I have put up the PRC and RHS LS7 small bore which have yet to become trendy because they haven't been out long enough. One guy here has them on his 429 in a 5th gen camaro and is making great power.

The numbers of that motor would be very peaky with a single plane intake which would require the OP to have a big stall and gear to race with and make it more track oriented unlike what the OP just posted. Yes you can run 12:1 on pump, but L92 heads have shown no increase in power in going to that much compression.

I wasn't suggesting that he needed to run that much compression, just that it "could" be done to bump power. A 1 pt increase in compression IIRC is about 4% gain in power. A simple calc of DCR would afford the OP to know how it would fair on pump fuel.

11-11.4 is where you want to be with them on pump. Also, depending on the OP's car, the vic jr might not be an option. So he would be restricted by an intake that has to fit the car. Any style ls intake has it limits so going to 12:1 or SR is null and void because the intake will hold it back from letting that characteristic shine to its full potential.

I didn't really read into what type of car this was going into...so I don't know what intakes he has access to. Regarless based on results I have seen, the type of increase in power from 4500- (both in HP and TQ) should offset any reduction in TQ below that number. The RPM drop between gear changes can be calculated based on trans and rear gearing to determine the ideal HP/TQ curve. But from what I have seen large increases in HP and even added TQ (even with a low profile elbow stuck on a single plane) can make this a formitable combination for a range of cars. I must apologize as I didn't read throughly his post about desired usage of the car, I just replied based on the fact he wanted to make the most power he could on a "drivable" combination, without breaking the bank with exotic parts.

Down the compression of that motor, put an LS style intake on it, and change the cam and watch that AI headed motor make the same power as the PRC headed motor.

As far as the heads I would put the PRC L92's up against the AI L92's any day.

I wouldn't. Head for head (243, 5.3L, L92) I wouldn't. I only speak from my personal experience in running a few different brands of heads compared with AI, factoring in the purchase expense. Im not knocking PRC or any other vendors heads, I just feel AI is a superior product (whether its porting factory or aftermarket castings.


They are both great heads and do really well. I've never mention any popular or trendy head. I have put up the PRC and RHS LS7 small bore which have yet to become trendy because they haven't been out long enough. One guy here has them on his 429 in a 5th gen camaro and is making great power.

The small bores have been around for nearly 2 years. With folks placing so much emphasis on flow #'s, this type of head has garnered alot of attention. Im sure they can make great power. Their aren't a plethora of results out there, at least that I have seen. That is why I restricted commentary to parts with a longer track record. Their are number of options available to him, in the end he will have to factor in plans for the car, with budget and power goals, and make a decision from those factors. I simply was giving him an example of the potential of this particular head on a similar sized motor, allowing him to extrapolate power potential based on factors relative to the specifics of his demands.



See above.

I'm between the trick flow 235cc and the prc 265cc either way I'm gonna get new rockers so which would u run?

I'm runnin a 408 now instead of the 418 I sold it to a friend for me than I paid lol

More* than I payed

Paid*

Well 408 takes the prc heads out of the equation

I'm between the trick flow 235cc and the prc 265cc either way I'm gonna get new rockers so which would u run?

depends on how much you want to spend. I am building a 408, using AI TFS 230's, a high 23x cam with about .600-630 lift. It was between T&D's or just sticking with stock with trunion upgrade. So I elected to stay with stock and trunion upgrade. By most accounts for a milder build like I'm building, this is very adequate, and a heck of alot cheaper than T&D...too many horror stories with Harlans and YT.

If you run AFR's then you are going to want to get a FAST intake because there is no factory cathedral intake that is going to flow the air for a 418.

The good thing about AFR's is that you can run the stock valvetrain unlike Trickflows because of the different valve guides.

completely false statement
i run a ls6 intake due to budget reasons and i still make 502hp and 488 trq

with a full stock intake setup

Just a side note on the Trickflows....if you want to run stock style rockers, you can just order powdered metal guides for the heads (about $100). Someone else may have mentioned that, but I just wanted to reiterate that.

The afrs does anyone have a part #? All im findin is 225 or 235 ls1,2 and ls6 not ls3 or 7

Fore sure rectangular port small bore thick decks cylinder heads, and must definetely Camhelp@Guerragroup.com and if you get lightened shaft mount rockers, i don't see the need for the bottle, just put the bottle kit money on your motor parts and keep it simple and you'll be flying, without a refill.

I called afr and they told me to run the afr 230cc large bore heads with 72cc

I called afr and they told me to run the afr 230cc large bore heads with 72cc

http://www.proheads.com/WCCH245.html

call rich at WCCH you will be more then pleased with those heads

the only company that called me about 2 weeks after my build to make sure the heads he sold me where what i wanted and the power i wanted to make was met

I called afr and they told me to run the afr 230cc large bore heads with 72cc

Check out this thread (if you haven't already)...They got your hook up, I promise...You are making phone calls..doing your research like you should, anyone about to drop 2-3K needs to be well informed. I would at the very least, give them a call to discuss your needs/wants/goals...it would be well worth your time.

Performance Induction/Mast LXR vs AI 5.3L back to back dyno (http://ls1tech.com/forums/dynamometer-results-comparisons/1453671-back-back-dyno-test-pi-215-s-ai-cnc-d-gm-5-3-a.html)

Cool thanks guys, there's a lot of thinking to do lol this is my first build and there's soo many options

completely false statement
i run a ls6 intake due to budget reasons and i still make 502hp and 488 trq

with a full stock intake setup

But you don't think there is power to be had with a better intake?

But you don't think there is power to be had with a better intake?

no i agree with you a fast 102 set up will put me easy into the 535 hp and over 500 trq i just did not have the money at the time to spend on the intake

no i agree with you a fast 102 set up will put me easy into the 535 hp and over 500 trq i just did not have the money at the time to spend on the intake

Point taken. LS6 doens't flow enough for a 418.

it flows enough to function

it flows enough to function

Not the point. It doesn't flow enough period.

A 418 with a ported stock LS3/L76 intake is close to a FAST on power numbers. An LS7 intake is close to a FAST intake on power numbers. An LS6 even ported is no where near a FAST intake.