• We've upgraded and reskinned the forum. Notice something off? Email us at [email protected] and we'll fix it.

V1 TravMac's Extended Track Goblin (#253) - 2007 SS/SC Doner

TravMac
New wheels and tires have arrived! Now, I go against a lot of what I've said and thought in the past about heat in the tire, and using wheel spacers here... But I'm excited to give this set-up a try anyways. Say hello to the new Hoosier A7's in 275/35 R15! I fit them onto the same brand of wheel, the Koenig Hexaform. Only these are a bit wider, going to a 15x9 with +35 offset. It didn't quite fit without some wheel spacers, shimming everything out another 15mm. Really excited to see how it all works if I can run them at the end of the month! Haven't ran a tire this aggressive before so really excited to see how it does from the 225 width Toyo.

1000016493.jpg 1000016496.jpg 1000016498.jpg 1000016497.jpg
 
TravMac
Still messing with some suspension stuff before I get to rip around at all, but something interesting after getting the scale out: the wider wheel and tire combination with the A7 is actually lighter than the Toyo setup I was running. The corner is now 33.1lbs, saving just over a pound per corner. I'm really itching to get it to the cone course.

I've also been calling and emailing about the rear cradle upgrade for the last month. Still trying to work out getting that. It truly would be the last icing on the cake of this set-up.
 
E
I'm currently in the market for some Hoosier A7's and new wheels. I have been looking at 275/35 R15 for the rear but not sure about the wheel width. Chatting with my autocross group someone had mentioned the side wall of the tire and that you are better to have it stretched in. So now I'm wondering if I have a 9" wheel width if i should go a bit smaller on the tire width? I'm currently running more of a street tire setup but it is a 275 with a 9" wheel and the sidewall is pretty similar to what you have.
 
S
I'm currently in the market for some Hoosier A7's and new wheels. I have been looking at 275/35 R15 for the rear but not sure about the wheel width. Chatting with my autocross group someone had mentioned the side wall of the tire and that you are better to have it stretched in. So now I'm wondering if I have a 9" wheel width if i should go a bit smaller on the tire width? I'm currently running more of a street tire setup but it is a 275 with a 9" wheel and the sidewall is pretty similar to what you have.
The 275/35 ZR15 calls for a 9-11 in wide wheel. Next size down for the A7 is 245/40ZR15 calling for a 8-9.5 in wheel width. I agree with your autocross group on not forcing a wider tire on a wheel. Test results I have read would indicate you could expect faster lap times using the 245. Overall tire width difference in the tread would likely be an inch or less on a 9" rim. I recently switched from 255 to 275 Nitto AR1's on a 9.5 in wheel and believe there is no gain in grip for me. Thats comparing a used up 255 to a new 275 as well.
 
Ross
Well, autocross is a cold tire event, as you only get about a minute of driving every 20 minutes. That said, at the end of the 3rd lap, coming in from a hot lap, the 275 A7's are picking up every rock on the asphalt. Probably because the sun is nearly overhead, and the heat of the day is arriving.

It amazes me how quickly tires heat up when cornering, and how quickly they cool down on the straight aways.
 
TravMac
I can try and answer given my experience so far on how these tires have performed up here in Michigan. Sorry I always type a ton... TLDR: get em, run em, enjoy em!

I'm currently in the market for some Hoosier A7's and new wheels. I have been looking at 275/35 R15 for the rear but not sure about the wheel width. Chatting with my autocross group someone had mentioned the side wall of the tire and that you are better to have it stretched in. So now I'm wondering if I have a 9" wheel width if i should go a bit smaller on the tire width? I'm currently running more of a street tire setup but it is a 275 with a 9" wheel and the sidewall is pretty similar to what you have.
I'd tend to agree with your autocross group. Being on the lower end of the wheel width spectrum for the tire is better than over stretching beyond what tire widths recommend. As Scott pointed out, the 275 is within the range of the wheel width on a 9" wheel, so it isn't outside the bounds of what you can do. I think all things considered, if I could fall more in the middle of the range, I would prefer it - but there's a cost and mass hit there that I couldn't find the balance of in available wheels to make it reasonable. Still though, the 275s on a larger width wheel were still lighter than my 225 R888Rs!

The 275/35 ZR15 calls for a 9-11 in wide wheel. Next size down for the A7 is 245/40ZR15 calling for a 8-9.5 in wheel width. I agree with your autocross group on not forcing a wider tire on a wheel. Test results I have read would indicate you could expect faster lap times using the 245. Overall tire width difference in the tread would likely be an inch or less on a 9" rim. I recently switched from 255 to 275 Nitto AR1's on a 9.5 in wheel and believe there is no gain in grip for me. That's comparing a used up 255 to a new 275 as well.
This is also a cool comparison with the Nitto's. I certainly picked up time in my tire change, but it was more of an apples to oranges comparison being R888Rs in 225 width to the A7 in 275. They were just night and day. I certainly used all of my tire without rolling beyond the tread in a pattern that seemed to align with the car's suspension setup. I can always go to a 245 on my 9" wheel in the future if availability or cost of 275s become an issue; but for now, they just seem to work.

Can you even warm up a 275 A7 on a Goblin?
Yes, the desired range is between 110 and 140F, and I fell about in the middle. This was actually using a pyrometer I borrowed at autocross, not just surface temps that I had been recording. Also to note, the commentary I had from folks who run these tires: the key is getting to temp and not overheating, which I never had an issue with. It seemed to be a great balance on my car. I could probably further benefit from a bit of a cover to keep the heat in like the cart guys run on cooler days.
 
Ross
I can try and answer given my experience so far on how these tires have performed up here in Michigan. Sorry I always type a ton... TLDR: get em, run em, enjoy em!
...

Yes, the desired range is between 110 and 140F, and I fell about in the middle. This was actually using a pyrometer I borrowed at autocross, not just surface temps that I had been recording. Also to note, the commentary I had from folks who run these tires: the key is getting to temp and not overheating, which I never had an issue with. It seemed to be a great balance on my car. I could probably further benefit from a bit of a cover to keep the heat in like the cart guys run on cooler days.
Oh, I feel better about my tire temps... I thought 170F was normal...
 
TravMac
I was excited to post that it is springtime in Michigan after a weekend in the 70s, but here we are... back to the 30s. False spring always hits hard.

A few little things to talk about on the build log. First: if you don't read anything else, and you're looking for an action camera, Costco has a huge deal on the Insta360X4 bundle with $100 off that I couldn't find anywhere else. I picked one up, and took a few pictures looking where I want to mount on car. Seems like along the rear firewall above the car looks the coolest in a sort of birds-eye view. This will be a huge upgrade to the old GoPro. Now for car stuff.

Car ran great the rest of the autocross season on the Hoosiers. Although it was another season of "win by default" I still learned a lot and kept finding new limits of the car. I was actually averaging consistently mid 80s for most of my pax scores, which felt like a huge accomplishment given the talent in the region. Then the car got cleaned up a little and put in the garage for the winter. I got it out last week to warm it up, cruise around the block, and make sure nothing was chewed up by mice over the winter. There's a little fuel coming out of the filter, so going to replace that in the regular yearly maintenance. Otherwise, it's running well!

This year will come the new DF rear cradle, actually installing the upgraded shifter, and... a trailer hitch! This car will be towing a little trailer during the Sick Michigan Miles event in August! It's a drag racing and road trip event around the state of Michigan. My buddy who helped me build the car got it all registered and he'll be doing the drag racing honors while I do pit crew (and maybe some work at the hotels considering how the job is going lately). I'm excited for the road trip and seeing what the car will do in the 1/8th mile. There will be much more to come for that!
 
Mahkoi
I was excited to post that it is springtime in Michigan after a weekend in the 70s, but here we are... back to the 30s. False spring always hits hard.

A few little things to talk about on the build log. First: if you don't read anything else, and you're looking for an action camera, Costco has a huge deal on the Insta360X4 bundle with $100 off that I couldn't find anywhere else. I picked one up, and took a few pictures looking where I want to mount on car. Seems like along the rear firewall above the car looks the coolest in a sort of birds-eye view. This will be a huge upgrade to the old GoPro. Now for car stuff.

Car ran great the rest of the autocross season on the Hoosiers. Although it was another season of "win by default" I still learned a lot and kept finding new limits of the car. I was actually averaging consistently mid 80s for most of my pax scores, which felt like a huge accomplishment given the talent in the region. Then the car got cleaned up a little and put in the garage for the winter. I got it out last week to warm it up, cruise around the block, and make sure nothing was chewed up by mice over the winter. There's a little fuel coming out of the filter, so going to replace that in the regular yearly maintenance. Otherwise, it's running well!

This year will come the new DF rear cradle, actually installing the upgraded shifter, and... a trailer hitch! This car will be towing a little trailer during the Sick Michigan Miles event in August! It's a drag racing and road trip event around the state of Michigan. My buddy who helped me build the car got it all registered and he'll be doing the drag racing honors while I do pit crew (and maybe some work at the hotels considering how the job is going lately). I'm excited for the road trip and seeing what the car will do in the 1/8th mile. There will be much more to come for that!

Good to know on the camera. I've been eyeing the DJI Osmo Action 5 but haven't got around to buying one yet.
 
TravMac
Also an awesome camera choice! I've just seen so much great stuff out of these 360 cams. Dont need to think about position, it'll capture everything!
 
TravMac
A lot of progress has been made getting ready for the August event. The year has been quite busy with family commitments, and haven't raced at all either, but each weekend of car work is starting to show! I have a week of vacation coming up to get everything installed and I'm excited for it!

I've attached some pictures from the painted cradle, the test of a lexan windshield. Soon enough, I'll have videos of driving with the full setup in July! Now to source some e98...

PXL_20250601_185645131.jpgPXL_20250518_181203134.jpgPXL_20250601_005759634.jpgPXL_20250601_125944191.jpgPXL_20250601_225229050.jpgPXL_20250601_225322892.jpgPXL_20250613_225933370.jpgPXL_20250518_121844762.jpgPXL_20250518_181213164.jpgPXL_20250601_142607443.jpgPXL_20250601_142613072.jpgPXL_20250613_225709441.jpgPXL_20250615_200949940.jpg
 
TravMac
I tried to upload as an mp4 earlier, but YouTube may better. Here's my first good car edit with the insta 360! Just playing with it but I'm excited for during racing.

 
A
I tried to upload as an mp4 earlier, but YouTube may better. Here's my first good car edit with the insta 360! Just playing with it but I'm excited for during racing.

Wow, just Wow. Great Day!! I want to drive my car sooo bad! I feel like a five y/o waiting for Christmas! I got part of the fuel filler neck welded today! (stomping feet) I - Want - Everything - NOW!{sorry, tantrum off now:rolleyes:} What a Day! Beautiful.
 
TravMac
Had a great start to the month getting to my buddy's garage and working on the goblin. Started in on the shifter install, got my harness recertification done, engine modifications added, and cradle set up! Also, trailer for the drag racing event is ready to roll! Now just need a fuel barrel.
PXL_20250630_162420226.jpg

Shifter note: for anyone doing the billet shifter from DF, the cover plates line up end to end well, but the shifter section is wider than the tunnel. I haven't shimmed it yet, but likely will. Some pictures for clarity below since I haven't seen anyone else post these. I'm also using bolts and drilling/tapping the tunnel where some of the rivets had lined up. The cool thing is most the holes from the previous tunnel already lined up!
PXL_20250701_010241742.jpgPXL_20250701_010245523.jpgPXL_20250701_010229310.jpg


The engine got new 82# valve springs, neutral balance shafts, an ATI superdamper (underdrive), and ZZP cams. I wasn't expecting to use the cams now, but I'm really curious to see how they do. Makes me wish I got the setup on the dyno before all these changes, but oh well. My buddy thinks we can do an even smaller pulley for the supercharger now that the ATI would be spinning things slower too, so looking at what we can do there (time for a 2.6?). Have to get a new idler pulley too since the supercharger belt doesn't fit anymore. ZZP has a solution so going to try that.

The cradle is still fighting a little. Going to shim the engine down in the chassis and see how that goes. And you may notice some other exhaust thoughts in the pictures too... As always, more to come.
PXL_20250630_125830697.jpgPXL_20250630_125845934.jpgPXL_20250630_125851694.jpg

PXL_20250630_125819437.jpgPXL_20250701_002148283.jpgPXL_20250701_001031538.jpgPXL_20250701_005455562.jpgPXL_20250701_010137270.jpg
 
comegetjoe
Shifter note: for anyone doing the billet shifter from DF, the cover plates line up end to end well, but the shifter section is wider than the tunnel. I haven't shimmed it yet, but likely will. Some pictures for clarity below since I haven't seen anyone else post these. I'm also using bolts and drilling/tapping the tunnel where some of the rivets had lined up. The cool thing is most the holes from the previous tunnel already lined up!
View attachment 52659View attachment 52658View attachment 52656

I have heard of no such issue until this.
I ordered my shifter with my original kit and tunnel and it fit without issue.

Nice tail lights :cool:
 
Back
Top