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After some more e-mails, and lots more research, I am going with AI 243s or AI TFS. Since AI welds 241 heads, I hope they will weld 243s and TFS. I am going to flex fuel, so more compression is one of the things I am looking for. Now I just have to wait to see if I get the extra travel for the TFS heads.
After some more e-mails, and lots more research, I am going with AI 243s or AI TFS. Since AI welds 241 heads, I hope they will weld 243s and TFS. I am going to flex fuel, so more compression is one of the things I am looking for. Now I just have to wait to see if I get the extra travel for the TFS heads.
Thanks everyone for your inputs.
if your hell bent bent on staying na, don’t waste your time with an ls1 or ls2. Do an ls3 swap. The heads are better stock than a lot of ported 243’s. Then you could port the ls3 heads. You’ll make a ton more power going this route for probably close to the same money. Sell the engine you have now and put that towards the ls3.
Man I just reread your posts. I hate to tell you but your wasting your time, money and making a big mistake in my opinion. Let me tell you why. I have a stock short block ls1 gto. Ported 243’s 227/234 cam, stall etc etc. it gets **** gas mileage, so bad (10-11) that I don’t drive it but maybe once a week now and I bought the car as a daily driver to keep the miles off my new truck. Yea. I ruined the car is what I did. And it sounds like your going even more radical. You could do a mild ls3 and put down more power, go faster and be way more drivable and fun than a radical ls1 or ls2. You have a $4300 budget right? I’ve seen ls3’s go for $3500. Then sell you motor and the money you have left over buy your cam and stuff and have some mild port work done. You’ll be much happier and thank me later.
Crazy how everybody on here have they own opinions but all are capable of getting the job done.
I've seen a 243 head by one of the best porters in world flow 390 cfm on the intake and 255 on the exhaust.
Man I just reread your posts. I hate to tell you but your wasting your time, money and making a big mistake in my opinion. Let me tell you why. I have a stock short block ls1 gto. Ported 243’s 227/234 cam, stall etc etc. it gets **** gas mileage, so bad (10-11) that I don’t drive it but maybe once a week now and I bought the car as a daily driver to keep the miles off my new truck. Yea. I ruined the car is what I did. And it sounds like your going even more radical. You could do a mild ls3 and put down more power, go faster and be way more drivable and fun than a radical ls1 or ls2. You have a $4300 budget right? I’ve seen ls3’s go for $3500. Then sell you motor and the money you have left over buy your cam and stuff and have some mild port work done. You’ll be much happier and thank me later.
If I was worried about gas mileage, I would just drive my Cavalier. I am not getting a new motor until I can afford the motor that I want. So, I would just be wasting money by getting an LS3. Plus, the AI heads will swap directly over to the motor that I want, and still work fine.
Crazy how everybody on here have they own opinions but all are capable of getting the job done.
I've seen a 243 head by one of the best porters in world flow 390 cfm on the intake and 255 on the exhaust.
That is the great thing about LS1Tech. You can get lots of ideas to research. You usually only have to deal with one or two asshats.
That is the great thing about LS1Tech. You can get lots of ideas to research. You usually only have to deal with one or two asshats.
True, I agree.... I just think some of the heads that was mentioned by other guys are over priced. The best value is PRC/Texas Speed if you already have some heads to begin with. Aftermarket heads I feel like TFS as cast heads are the best BANG FOR THE BUCK. You can always go back later and get them fully CNCd.
if you are getting 10-11 mpg ur either full throttle all day long or somethings wrong. i avg 21 mpg and thats with a 236/238 and i usually do about 8 full throttle pulls per tank in an M6
if you are getting 10-11 mpg ur either full throttle all day long or somethings wrong. i avg 21 mpg and thats with a 236/238 and i usually do about 8 full throttle pulls per tank in an M6
just for you I’m driving the gto to work this morning. I reset my mileage and I’m going to drive it normal and not get on it once. My issue is it sucks gas at idle like there’s no tomorrow. It idles at 775rpm and a 14.4-14.5afr. It doesn’t even smell like gas. It cruises averaging over 20mpg but the idling kills it. I sit in traffic a little bit. Car weighs 4000 with me in it. 3.46 gears. My 2017 Silverado averages 18-22 for comparison on the same drive.
op i mentioned the ls3 early on. You could actually come out pretty good on doin that swap because guys will still pay a premium for a ls1. Like i said a bolt on ls3 will meet your goals and not have any reliability issues and get decent mpg's. We just got my buddy's bokt on ls3 vette to go 10.5@131...so power will not be your issue. You getting it down the track will be.
op i mentioned the ls3 early on. You could actually come out pretty good on doin that swap because guys will still pay a premium for a ls1. Like i said a bolt on ls3 will meet your goals and not have any reliability issues and get decent mpg's. We just got my buddy's bokt on ls3 vette to go 10.5@131...so power will not be your issue. You getting it down the track will be.
glad there’s at least one person who doesn’t think I’m an asshat for that suggestion.
if you are getting 10-11 mpg ur either full throttle all day long or somethings wrong. i avg 21 mpg and thats with a 236/238 and i usually do about 8 full throttle pulls per tank in an M6
Real world mpg
227/234 btr stage 2 cam
ported 243’s
3400 yank
4000lb car
13.1mph driving normal. No flooring it. Bout 10-12 minutes in traffic. Few short red lights. Drive through for breakfast which was empty so I didn’t sit long. Afr’s are dialed in perfect. Maybe it’s the weight? Maybe it’s the cam? I lock the convertor up at 38mph in third gear. So it’s not slipping much. It does not bog and mpg picks up a tad when I lock it. The mpg took a nosedive with the cam. It would get 15-16 sometimes 17 before. That’s in traffic comparing apples to apples. Highway mileage is good.
OP, I am in the same boat as you. I have a decent cam and a fast 102 already. I have never touched my stock heads other that a spring change. I also want to stick N/A for now and have 2 sets of 243 heads in the garage. I was 90% sure I was going to send my stock 241 on the car now to AI, but an email with AI about the 241 porting and they talked me into buying a set of 243 as they said it would be much better for the $$.
That was all about a year ago and I still have the 243s sitting here. I am a big fan of the Mamo heads.....but they get pricey with the all the rockers, pushrods, ect.....
Seems like I get super excited to send the 243s off to get worked, then I read and read and my mind slowly gets convinced to go aftermarket casting. As of right now I as 50/50 on weather I should port the 243s or get some aftermarket castings.
I average low 20s with my stalled car. I have done 12 hours trips with it and drive it everywhere in Florida. I can drive it anywhere and have.
Sounds about right...mine cruised around 22mpg and averaged around 17 flogging her frequently. When the car was bolt-on only it was 24/19...so it didn't lose much and most of what it did lose was due to locking the converter at 50mph opposed to 38.
So this is just a little chart I have been adding to over the last year as I see head flow numbers and new ones show up. Obviously flow numbers are like dyno numbers and are to be taken with a grain of salt but at least it's something to go off of.
Real world mpg
227/234 btr stage 2 cam
ported 243’s
3400 yank
4000lb car
13.1mph driving normal. No flooring it. Bout 10-12 minutes in traffic. Few short red lights. Drive through for breakfast which was empty so I didn’t sit long. Afr’s are dialed in perfect. Maybe it’s the weight? Maybe it’s the cam? I lock the convertor up at 38mph in third gear. So it’s not slipping much. It does not bog and mpg picks up a tad when I lock it. The mpg took a nosedive with the cam. It would get 15-16 sometimes 17 before. That’s in traffic comparing apples to apples. Highway mileage is good.
i never trust the mpg that the car says. go fill up, drive an entire tank without ever getting on it at all, then refill out and calculate your mileage.
honestly, i think the main benefit of an aftermarket casting is that not only do they address high rpms, the address mid and low end rpms to aid in significant gains across the board. i believe ported stock heads get pretty close to the same high end gains but dont pick up as much average as the aftermarket
