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That's the crossmember I'll be getting to allow my Vette cased 4L60 to be installed behind a Gen 1 SBC. Thing is Holley, through my conversations with Toddoky, says that particular crossmember requires the use of their specific engine mounts, which moves the LS based engine forward. That way the LS T56 (as opposed to the LT1 T56) can be used without modification.
The crossmember is also said to work with a Gen 1 SBC and a LT1 spec'd T56. This closely approximates the length of a short tail TH400 (which coincidentally is the approximate mounting length of a 4L60 using a b-body extension housing with mount). This is done with the factory engine mounts and mount locations.
In his description. gixxer said his LS engine is in the stock Gen 1 location. Something isn't adding up.
Not meaning to hijack or anything it's just that this is the first time I've seen this crossmember used and I have questions regarding the fitment.
Don't over-think things here skinnyz, the Hooker third-gen LS engine mounting brackets moves the stock SBC engine/transmission mating plane forward by only about 5/8", so the Hooker crossmember will ending up working with some other combinations of aftermarket parts. The problem lies in the fact that there's no way to judge compatibility without physically installing the parts as many aftermarket parts have geometry that is other than what is advertised and the Hooker crossmember center beam comes very close to the case of the T56 even when used as designed with the Hooker engine brackets. In your case, you'll have much more leeway as your transmission pan will come nowhere near the center beam.
Not so much over-thinking as it is thinking it through.
The internet provides so much information, some of which may be a little misleading, that I'm trying to approach this from as many angles as I can.
Based on our other conversations, I'm pretty sure what I'm getting in to. Modifications to the crossmember (to work with a stock location Gen 1 SBC and a "B-body" 4L60 (Vette case with a b-body extension housing) are, I think inevitable, however the changes should be very modest. As you suggested Tod, perhaps only slotting the holes in the crossmember will be needed. The exhaust on the other hand, being a unique piece in my case, is the other variable to deal with. There looks to be plenty of clearance with the high arches of the Hooker crossmember but I won't know for certain until I'm under the car working on the fitment.
Thanks again toddoky for your input. It's very much appreciated.
Here's a photo I dug out of my files that you might find helpful...it shows the Hooker 3rd-gen transmission crossmember and dual exhaust system installed in a SB Chevy/LT1 T56 application. It works in this instance because the LT1 T56 transmission is 5/8" shorter (bellhousing face to mount) than the LS1 T56 transmission.
That IS a helpful picture.
And based off of that bit of information, (the LT1 T56 transmission is 5/8" shorter), that means that my transmission rear mount will be 1 9/16" further back (than that of the LT1 T56).
LT1 T56 bellhousing to rear mount at 26 3/8". B-body 4L60 bellhousing to rear mount, 27 15/16" (if the internet's description of the B body 4L60 is the same as that of a TH400)
Now, having had a chance to examine a few of these installations, I can see a few problems going forward. While I can adapt an offset mount to capture the locations between the crossmember and the transmission, I can't see how my existing y-pipe will fit. Unfortunately for me, where my y-pipe transitions to the merge pipe is directly under the Hooker crossmember. It's not going to fit with out a redo or replacement.
The images you posted are examples of the erroneous information that can be found online...the actual mount distances for those transmissions from the bellhousing mating surface is as follows:
LT1 T56- 25.992"
LS1 T56- 26.617"
TH400 with 4" extension housing- 26.875", same as the 200R4 transmission
I know these dimensions to be correct as I use them in an almost daily capacity to design transmission crossmembers for the various LS swap systems I develop...I've measured these transmissions and 13 others with a 36" vernier height gauge on top of a dead flat table.
Yes, your Y-pipe would be problematic from a compatibility standpoint.
Hooker Super Comps with custom hedman s tensions and flowmaster delta force race mufflers.I have about 3.5" of clearance at the s tension and 4" at the mufflers.
you wouldn't happen to have or be able to get a better picture of how you mounted the read exhaust hangers.
That's a very nice looking system. One bit of criticism, perhaps more of a caution. Those tips look like they end up really close to the ground and beyond the rear bumper. You'll need to be careful backing up to curbs. You'll cry if you run one of those tips into the concrete and tweak your system. May find you'll be happier with tips more like OE.
Figure I would add mine too. Just completed this year before Thirdgen Expo.
1 7/8" to 3" collector SS headers by hawks.
Custom fabbed exhaust using vbands from front to rear
Key difference is I went over the axle on both sides
Figure I would add mine too. Just completed this year before Thirdgen Expo.
1 7/8" to 3" collector SS headers by hawks.
Custom fabbed exhaust using vbands from front to rear
Key difference is I went over the axle on both sides
That's a very nice looking system. One bit of criticism, perhaps more of a caution. Those tips look like they end up really close to the ground and beyond the rear bumper. You'll need to be careful backing up to curbs. You'll cry if you run one of those tips into the concrete and tweak your system. May find you'll be happier with tips more like OE.
Just a thought.
I know you got a point mate, however i wanted it to look like this. It had bolt on tips when i bought it which faced down although not as much as these. I'll be very carefull with it to be honest. If i find it to troublesome in the future i'll change it. However as for now, i think it can get away with it. I'm also creating some portable ramps for in the trunk which i'll be able to use to get over certain speedbumps if needed. However i mostly will drive it on freeways and avoid speedbump infested areas as much as possible.
Originally Posted by QwkTrip
Did you shop RVtrader for those exhaust tips?
Won them at an ebay auction mate, not sure where they originate from. I was looking for a set like this for a while.
Texas Speed Performance is now offering this dual exhaust kit for the fourthgen for $500
THAT is interesting. And modestly priced too.
Those headers remind of the Super Comps I have on the big block TA. Exiting more towards the rockers and away from the transmission than a typical header. Not that it would matter in my case. I'd have to build the intermediate pipes from the headers to the "X" anyway.
Do you have a link to that part? I couldn't find it on their web site.
Last edited by skinny z; Oct 11, 2017 at 07:56 PM.
yes. in fact, we have a magnaflow catback from a buddy's 2002 formula on my little brother's 5.3 swapped 89 iroc. there are a few details that have to be addressed concerning hangers, but it's not a lot of work.
yes. in fact, we have a magnaflow catback from a buddy's 2002 formula on my little brother's 5.3 swapped 89 iroc. there are a few details that have to be addressed concerning hangers, but it's not a lot of work.
Well, as mentioned earlier, that really opens up options for exhaust then.
I have dual 3" from the headers. It would be really nice with dual 3,5" but its very tight to get that all the way back with TA and stock fuel tank. But I think the 3" system steals some power now when were at 1000+ hp. Maybe some oval pipes can make it happen :P
I have dual 3" from the headers. It would be really nice with dual 3,5" but its very tight to get that all the way back with TA and stock fuel tank. But I think the 3" system steals some power now when were at 1000+ hp. Maybe some oval pipes can make it happen :P
This thread is very helpful. Here’s a picture of my true duals using hawks crossmember, eBay headers that come with the two pipes and ugly y merge that I didn’t not use with spin tech mufflers. Anyone recommend other mufflers? Thanks!
Dual 2 1/2 exhaust mostly straights and 45 degree bends just the cheap stuff from parts store.It was same clearance as factory exhaust from the ground when I was done.
Nice work 427seven!
I like the routing. Nice to see the canton (242-T?) works with the stock crossmember and that the exhaust passes so well in that area!
Using a heat wrap or blanket to keep the heat off the oil pan?
What does the "bump" look like on the inside with the floor board/back seat area?
It is routed that way to equalize the lengths and the bump is under the seat rails which are modified Corbeau units and had to be "fitted" bc of the hump. Nothing major, just a little notching with a grinder, and I had to paint them to match the seats anyway. The heat shield had to be put in. Even before this exhaust system I had a mild steel 2.5" system I used for the initial design, and the power plant puts out so much energy that it was just HOT. This shield cut the heat in half, so I decided to add it to the CANTON 15-244. I've "cruised" the car in stoplight traffic for 4 hours and the temps don't budge, always right at 185-190.
