jimbob

iTrader: (4)

The PORT ADAPTER is the name of the ADAPTER that the FAST LS7 uses on the lower shell for each port, see post 26. "You should know this," as they are not sold separately yet, so don't screw one up with porting.

You can take this with a large grain of salt...It looks like we gained about 10 rwhp. After LS2 Portworks re-ported my manifold and modified the adapters. Since, I also raised the compression at the same time I can only use know percentage gains for each compression point gain from my starting point. We overall gained 27 rwhp. Calculated out to 16 rwhp gain from compression increase, again "Calculates." I due wonder how many have slight misalignment issues and don't know it..? Not saying it would be large like mine but there could be a few hp's making sure the ports line up...

Also, the port dimensions were measured along with the bottom of port from deck surface. Unfortunately, we had "NO" known reference for a Stock LS7 heads from the "deck surface measurement," since block deck height, along with head gasket thickness can affect these measurements, the point seemed moot. My guess, my ports are taller by a tenth than the average LS7 head.....

slippi84

iTrader: (4)

Oh ok I thought you had like a ls7 intake and l92 or ls2 head and had a adapter inbetween. Thats just the lower shell not an adapter

O.N.

slippi84 you said you have an LSX right or someone else did can you get some photo's up please?

looks like im going to have to make adaptor plates for my harrop intake if these bolt holes are 100-150thou short in comparison to the ls7 bolt holes.

slippi84

iTrader: (4)

I can try when I go to my tbss but I can guarentee its gonna bevery simular to yours.

slippi84

iTrader: (4)

Im just gonna switch to a gmpp cast bottom and found a guy making efi elbows. That way ill know it lines up and it will make going dp with my nitrous setup a piece of cake.

slippi84

iTrader: (4)

I put my LSXR up for sale and I bought the 19244033 and the aron elbow for 102mm tb. Should be beast with a direct port kit. Anyone want a LSXR LS7 intake

jimbob

iTrader: (4)

Actually, to get this info out (also so I won't get a that's not right), I'll explain better. The port adapter fits into a slot from the head side into the lower shell. On post 26 you can see the bottom of the port has a gap. The gap is caused because that bottom piece you see slides out tward the head (hard to explain...). You can see how if you raise that adapter, you'll have to smooth the transition to the now higher port, to the horn.

Sounds like in both of your choices your both going different manifolds.

ChucksZ06

iTrader: (9)

I am no advocate for Fast products but unless you have a tall deck block I do not see what the problem is. I have an ls7 block with the lsx heads and a fast 102. You bolt the lower half of the intake to the heads(already bolted to the block...mocked up you know) and then you match the ports perfectly with the head ports and do any other porting to the balance of the intake you deem necessary. I have done this with various cathedral port builds also and never a problem. I always wonder how the manifold porters can match up the ports without having your engine on site...I believe they do not match up if you were to properly check out the alignment of the lower half. I wish their was a less expensive way to go with the ITB's.

slippi84

iTrader: (4)

Yeah I'm not messing with any adapters or spacers the GMPP LSX ls7 single plain standard deck intake manifold for carbs drilling out the fuel injector bung holes throwing a Arons elbow for 102mm tb on top and calling it a day. I know for a fact that everything will fit perfectly no port mismatches or porting needed. Like the fact that O.N spent almost 5k on a intake and still needs parts to make it fit it were me would make me blow my lid.

O.N.

Yes but you have no idea if the lsx ls7 intake fits ls7 heads properly or lsx heads, clearly the lsx heads seem like they have different bolt hole locations so does this intake suit the lsx or the ls7 you'll find out when you get it.

as for the harrop a simple adaptor plate is need and having access to cnc and laser cutting machines its no biggy to make something up and or if needed cut the flange off the harrop intake and make a new flange or even just relocate the bolt holes on the harrop intake.

Metal is going to be alot easier to work with compared to the plastic fast manifold.

slippi84

iTrader: (4)

My new intake was made especially for the lsx ls7 heads so I DO know it will fit perfect. It's not made for ls7 heads but LSX ls7 gmpp heads.

O.N.

yeah i know it is specific but the LSX heads are suppose to be the exact same "as cast" LS7 with a 6th bolt hole and a thicker deck. So who is to say they fucked that up that they also fucked up the intake for it...... just saying double check it when you get it. use a micro cam if needed and look down the ports.

dr ls7

I'm running a gm ls7 block perform ind lsx ls7 heads and perform ind 2 piece Cnc Lsx
manifold and the precision fit to the ports are PERFECT

slippi84

iTrader: (4)

No I mean they sell this intake with the engine if you want it in carb from its literally made just for this engine and this head not just for any ls7 head. Actually makes sense now cause they had one intake that said for LS7 heads and another that said for the sx ls7 single plain standard deck. http://www.crateenginedepot.com/stor...P2512C122.aspx

It even has LSX right on the manifold

ChucksZ06

iTrader: (9)

O.N. Do you not read the posts that are answering your questions. You are obviously doing something wrong. Find someone local that has the mechanical skills to see if you have interference fit or what is wrong. So many internet posters get on here and complain about problems with products and it is their own ignorance or incompetence that is the problem.

O.N.

it's been read and understood completely simply put the fast 102 fits an ls7 and not and lsx ls7.
and adapter plate needs to be made or better still get the harrop and then make an adapter plate or fill in the harrop bolt holes on the flange and make new bolt holes and/or cut the flange off a brand new intake and make a new flange that fits, the ports all line up no problems just dont bolt it down cause the bolt holes dont line up..

Point being GMPP were dumb enough to bring out a head and give it a name called LSX LS7 "as cast LS7 but its not as cast the bloody bolt holes are in a slightly lower location.

SweetS10V8

iTrader: (4)

Then I think should edit this thread entirely....

You beat up FAST pretty hard, and it was totally unwarranted. It looks to be user error by mismatching incompatable componets.

O.N.

well no it's not user error at all the thread should start off by beating up the LSX heads....lol and not the fast manifold.

we were all told the LSX heads are as cast LS7 heads with only a thicker deck and a 6th bolt hole. when in fact the dumb asses at gmpp made the holes lower for the manifold. And they all told us that LS7 intakes will fit no drama's and yep they fit and yep the port sizes are the same but when you do bolt it down it bolts slightly lower.

I think the thread can stay as it is people can read onwards and see how the thread has progressed into diagnosing the problem with the head/intake combo and how we have all yet again been told false info from gmpp.

LSX LS7 heads are not LSX LS7 they should just be called LSX heads there is nothing LS7 about them, other than port design.
It's such a stupid error on their behalf. and good luck getting them to fix their **** up.

slippi84

iTrader: (4)

I never read them say any of the stuff your saying. All that makes a LS7 a LS7 head is the ports. That's why you can bolt ls heads to other ls blocks. I really don't see how either company fucked up you just didn't research enough. GMPP offers a intake for the heads that bolts right up and says its different from the regular ls7 head with the fact they mak a solely lsx ls7 intake for standard and taller deck aside from the ls7 intake.

O.N.

well no they say it is "as cast ls7 heads" which gives the impression they are exactly the same other than the 6th bolt hole and a thicker deck.

Even when the rep from gmpp in the youtube video is explaining the differences between the 2 heads hey says "it is the same other than those 2 difference's" and to say its just a specific lsx intake is bullshit because if they wanted just LSX intakes why would they give it the exact same bolt pattern to bolt the LS7 manifold up but **** it up by 5-8mm in depth.....its a **** up on gmpp's nothing more nothing less we were all told AS CAST LS7 with 2 additions. meaning its identical but slightly better.