travenport

Hey guys i was looking for a little advice before i pull the trigger on my build.

Ive got a great looking fb roller and im planning on going the LS route with it. Ive got a couple options and just wanted to to make sure I had the best information before starting.

I've got the option to buy a very used '98 LS1/T56 (175k) for around $2000. The obvious concerns with this is the age of the motor/trans combo and ive heard that pre-99 motors were prone to piston slap.

My other option is a $2500 vette motor with only 59k on the odo. Concerns with this route are finding a good condition T56. Also the fact that since it is not Fbody, I will need to mount the accessories in a different spot from what i understand. Which, combined with buying a tranny will significantly add to the cost.

My question: Are the '98 LS motors reliable enough for me to trust a 175k motor, or should i dish out the extra money for the second option?

Also, ive tried the search and have not seen a comparison thread for FORD vs CHEVY in an FB. Ford does seem to be the cheaper route, but i feel the LS swaps are more documented. If such a thread exists can you direct me to it.

Thanks

86svo9l

Do you have a chance to hear the 98 engine run? I have encountered a few 98 LS1 engines that had bearings 7 and 8 toast from oil pump failure. If you do go check it out ask the oil pan to be removed and check for bearing play and check the pickup for metal shaving debri if it is out of a vehicle.

Ford options are nice too. Back in my Mustang days I could get a 96 Explorer 5.0 sent to my door for $500, spend another $600 on a T5, $1500 on a used supercharger kit and have a 400hp setup on the cheap.

LargeOrangeFont

iTrader: (7)

I'd do the 98 and rebuild it. You'll be very far ahead that way.

valley

iTrader: (1)

The 98 blocks had bores that could not honed/bored. They also have some nuanced differences beyond the wiring. Frankly, I'd avoid a 98 block like the plague. However, if the engine has decent compression I'd consider buying the combo and selling the engine and looking for an 00+ engine from an f-body.

travenport

That sounds like 3 for the f body and 0 for the vette. I was thinking along the same lines as well. The vette will probably end up costing me a lot more in the long run due to the modifications I will have to make. Auto to manual tranny kit/mount kit/different mounting position / etc. Thanks guys

LargeOrangeFont

iTrader: (7)

It is a myth about not being able to bore the 97-98 blocks. My block is a 98 and was bored .007" and it is fine. If you are leaving the car NA, I would not worry about it at all. If your cylinders are in good shape they will just hone them anyway as part of the rebuild.

There were incremental improvments to the LS1 block from 97-02, mostly around the oiling system. The "best" ones were the 04 GTOs/LS6 blocks, but none of those improvments are great enough to shy away from a good deal on the 98.

One thing you may want to do if you rebuild the 98 is to ditch the perimeter style heads. The centerbolt style head of the 99+ LS engines is much more popular. Also you can only use the graphite head gaskets on the 97-98 heads. If you go to the newer 99+ heads you can use the MLS head gaskets which are easier to work with, and easier to change/remove.

Performance wise the two head styles are about the same. the newer 241/853 centerbolt LS1 heads are supposedly worth a couple HP. People nearly give away the 241/853 heads, so you can get a set complete for cheap and have your machine work done on them. You will need valve covers, and coil brackets as well. That is stuff you can get used for pretty cheap.

I made the switch to the newer heads when I rebulit my 98 LS1 I got a great deal on a set of 241 heads that were fresh from the machine shop. The heads were basically free.

travenport

^^^Great info. Thanks

Ronin Speedworks

You might also note, that there only a handful of guys swapping FB's. Not quite sure why that is but I know Ronin's never had enough interest to justify the R&D required. You might be able to use our FC kit with a swapped FC subframe but I'm not sure on that.

Otherwise Grannie's Speed Shop might have something, but regardless, you're headed for a road less traveled which means it's worth less at the end of the days and you're in for more headache figuring it all out.

travenport

Yeah Granny's seems to be the only place around that sells items for this swap. I'm fine with the road less traveled on this project as I'm not interested in the resale value. This, along with my FD are collectors that will most likely stay in the family.

BTW went ahead and went with an LS1 and T56.

Ronin Speedworks

Heck of a lightweight chassis. Should be a serious car when you're done. If you're interested Ronin has access to all the original IMSA FB widebody bits.

travenport

I'm Interested but I only saw FC/FD on your website.

Ronin Speedworks

The FB IMSA parts aren't on the website since we've never actually built them for anyone. They're the originals but I can't vouch on the fitment being good or bad as they were run on race cars. As mentioned finding someone who want to spend the time and money making an FB top shelf is already a little rare. I'll see if I can find some pictures.