TimGreen

Wow, I don't have any answers and the original pistons are with the block at the machine shop. They are waiting on my being able to tell them the maximum bore they can do but first I have to find a high compression piston that is oversized for the A15 block.

I am building a new race motor for my Datsun B210 ChumpCar. I am using a Datsun A15 block, crank and rods with a H79 head. We plan to overbore as large as possible – depending on what high compression pistons can be found. If you have any recommendations please help me.

Please email me regarding the valve springs tim@914-6.org

Tom - Are the valve springs new or used?How much do you want for the springs? What valve guides do you recommend I get from Rock-Auto? Tim

Well we finally solved the "Over Heating" issue - unbelevable discovery. It turns out the last owner put the water temp probe in the thermostat housing hole for the exhaust gas EGR - so in fact we were never reading water temp. We did clean the radiator, replaced the water punp and thermostat and now have the water temp sensor in the hose from the thermostat housing to the radiator - PROBLEM SOLVED !!!!! Car ran fine last weekend at Blackhawk Farms with the exception of a little off road excursion... Now we can get back to adding a little more power to the race car. We did get an H89 head recently so now I need new springs, guides, and maybe a little porting.

I really like this idea and probably should consider buying a stock A14 head to modify so I don't interrupt the summer race schedule. This way he could possibly have the extra power for the September/October races. This weekend we removed the axles, changed the diff to the 3.89 (locker), changed the water pump, reinstalled the freshly cleaned radiator, and some other minor maintenance. We are looking forward to the two races over Memorial Day weekend, Any ideas on the cost of an stock A14 head?

Please remember this is a RACE CAR, when I mention it doesn't rev over 5,500 RPM I am referring to its ability to accelerate FAST. We shift up when the engine is out of its power band and this engine's power band is over at 5,500. It was chassis dyno'ed in March 2011 with 50HP and 68.61 ft-lb torque. It has an electric fuel pump at the fuel cell and is regulated down to 3.25 pounds very near the Weber carburetor.

My grandson raced go-karts when he was young but had never raced cars. He did his first drivers school and race 2 weeks ago, unfortunately we had over heating issues all weekend so he never got a chance to do multiple laps at max but we could hear as he went past on the main straight shifting from 3rd to 4th very little increase in engine RPM. I agree we don't want to build a killer engine at this time but I would like one that revs above 5,500RPM. I have been instructing wheel-to-wheel for years and totally agree, learning with limited power teaches car control and momentum driving. Can't wait till 5/26-27.

He is already going past the 200' marker so the brakes are working pretty good, but the car is not accelerating all the way down the two long straightaway's. I think the taller diff will help for the next race and hopefully we will have solved the overheating with the radiator professionally cleaned and a new water pump (with cast impeller).

Schaumburg is about 25 minutes from our house (near DuPage Airport (KDPA).

Unfortunately I didn't build the car (I just recently bought it). I don't have a lot of information on the modifications and no idea how it was from the factory. It has sway bars front and rear, it appears to have the original brakes (disk front, drum rear). coil over front and rear (second set of springs came with), and single adjustable shocks. We have not aligned or done corner weights yet - ran it as it was last raced as a Chump Car at Heartland Park 8/5/11.

If anyone has a H-165 differential with 4.11 gears (or taller) available - please PM me. If anyone has a H89 oval port head available - please PM me. Thanks, Tim

The thermostat plate is still there with the original hole, we simply removed the movable piece and spring. I agree you can not remove the entire thermostat, you would probably get cavitation in the water pump at higher RPM's which would produce little or no water movement. It is a common practice in race engines to do exactly this to prevent a closed thermostat failure.

I am told the rear end is a H165. We found today it is a locker (welded spider gears) and so is the 3.90 we will install before the next race. Now trying to find out what gears are in the 4-speed manual transmission.

We just looked under the oil cap on the head is107.